Treatment Modalities For Ectodermal Dysplasia Patients At A Tertiary Care Hospital

 

Syed Rashid Habib1                 BDS, FCPS

Fahim Ahmed Vohra2            B.D.S, MFDS, MClinDent, MRD RCS

OBJECTIVE: The objective of this study were to 8To obtain the profile of ectodermal dysplasia (ED) patients reporting to tertiary care dental hospital for oral rehabilitation. 8Report treatment modalities offered to ED patients

METHODOLOGY: It was a cross sectional study conducted at department of Prosthodontics, de’Montmorency College of Dentistry, Lahore. The duration of study was one year. One hundred ED patients were selected by purposive non-probability sampling technique. After taking consent, structured Performa was filled. Their clinical features were noted, radiographic analysis was also carried out and treatment was provided. After collection of data, statistical analysis done by SPSS software program and results were tabulated.

RESULTS: A total of 100 (57 male & 43 females) patients were included in this study. These patients were divided into five groups on the basis of their age. 42 males and 21 females had history of ED in their family. On the basis of missing teeth pattern, 27 % patients were categorized into mild to moderate hypodontia, 69% had severe hypodontia and 2% had anodontia. Conical teeth were found in 30% patients while 11% had peg shape teeth. In 40% patients mandibular third molar were un erupted (38 & 48 both 20% each) while 23% had un erupted maxillary third molar (18= 11% & 28= 12%). In one patient left maxillary second molar was unerupted and in one patient all mandibular incisors were unerupted.

Removable partial dentures were fabricated for 72 patients (females 32% and males 40%). Partial over denture were provided to 08 patients while for 64 patients, conventional removable partial denture were fabricated. Conventional complete dentures were provided for 10 males (10%) and 4 females (4%).  Fixed Prosthodontics treatment was provided to 15 patients, 8 were males (8%) and 7 were females (7%). Five patients did not come on their subsequent visits, so no prosthodontics treatment was provided for these patients

CONCLUSION: Most common presentation of ED patients was severe hypodontia. Patients were treated with removable and fixed prosthesis.

KEY WORDS: Ectodermal dysplasia, hypodontia, Prosthodontic treatment options, removable and fixed prosthesis.

HOW TO CITE: Hussain M, Yazdanie N, Hassan SI. Treatment Modalities for Ectodermal Dysplasia Patients at a tertiary Care Hospital. J Pak Dent Assoc 2013; 22: 261-264.

INTRODUCTION

The National Foundation for Ectodermal Dysplasia (NFED) defines ectodermal dysplasia as a ‘‘genetic disorder in which there are congenital birth defects (abnormalities) of two or more ectodermal structures”1.

Hypdontia (absence of one or several teeth excluding third molar) and anodontia (absence of all teeth) are associated with Ectodermal dysplasia.  Hypodontia is more common in permanent dentition with a higher frequency of 3:2 in females. Males tend to have a single missing tooth where as females more commonly have two or more missing teeth. On the basis of missing teeth, hypodontia can be classified into mild to moderate, severe and anodontia2.

The remaining teeth are small, conical or peg shape, infra occluded, with marked loss of vertical dimension of occlusion, and underdeveloped ridges. Extra oral features are characterized with fine and sparse hairs, malformed nails and pigmentation on skin. Decrease salivary and sebaceous gland secretions are also found 3.

Multi disciplinary approach is often required for oral rehabilitation of such patients, before embarking upon any prosthodontics treatment. Factors such as number of teeth to be replaced, adjacent tooth condition and position, periodontal condition, amount of alveolar bone, patient motivation, social and medical conditions are considered4.

Treatment options may include conventional removable prosthesis including over dentures, fixed prosthesis, implant-supported prosthesis, implant-retained prosthesis or combination depending upon the severity of disease and patient’s need 5. Early treatment provides an opportunity to develop normal speech, better chewing, improved swallowing and good facial support with improved temporomandibular joint function6. At an early stage removable prosthesis is the best choice, which may be relined or rebased at a later stage. Fixed prosthesis or implant supported prosthesis is preferred when growth is fully achieved.

Although the fabrication of removable partial denture provides better function and marked improvement in esthetics, but placement of clasp assembly poses some difficulties since the teeth are small and conical in shape. In anodontia the treatment of choice is conventional complete dentures at an early stage. Patient cooperation and proper behavioral management techniques are critical factors for the fabrication of conventional complete dentures at an early stage 7.

Over denture is also one of the important treatment option for ED patients, as presence of conical shape teeth with reduced occlusal vertical dimension along with aplasia of alveolar bone in the edentulous area makethe fabrication of over dentures easy and convenient for such patients 8.

In fixed prosthesis, different options like resinbonded bridge, conventional bridge and implant supported prosthesis are available. Resin- bonded bridge is indicated when minimal amount of tooth is available for preparation. Conventional fixed prosthesis is indicated where edentulous span is short, it is more esthetical and stresses can be evenly distributed, preparation of abutment teeth in patients of ED patients requires care to avoid any pulpal exposure9.

METHODOLOGY

It was a cross sectional study carried out in the Department of Prosthodontics, de’Montmorency College of Dentistry. The duration of study was one year. One hundred diagnosed ED patients were selected by purposive non-probability sampling technique. These patients were diagnosed on the basis of clinical examination and OPG. After taking consent for collection of data, structured performa were filled. Patients with impacted or un-erupted teeth, missing teeth due to caries, periodontal problems, trauma and extraction were excluded from the study.

Clinical features of the patients were noted, and OPG was also carried out. Various treatment options were offered, with consent of patient desired treatment was provided. After collection of data statistical analysis done by SPSS soft ware program and results were tabulated.

For numerical data like age, mean and standard deviation were obtained. For qualitative variables like gender, family history of the patient, patient’s past dental history, disease/s along with details of ED and dental treatment provided to such patients, frequency and percentage were calculated.

RESULTS

Total 100 patients were included in this study, 57 patients were males while 43 were females. Sixty three patients (42 males and 21 females) had history of ectodermal dysplasia in their family as well. All patients were divided into four groups on the basis of their age. Group 1: range from 1-10 years. Group 2: range from 11-20 years, Group 3: range from 21-30 years and Group 4:  above 40 years. In this study most of the patients were from group 2 (56%) followed by Group 3 and Group 1 i.e. 16% and 13% respectively, only 2% patients represented in Group 4.

On the basis of missing teeth pattern, 27 % patients were categorized into mild to moderate hypodontia, 69% had severe hypodontia and 2% had anodontia. Conical teeth were found in 30% patients while 11% had peg shape teeth. In 40% patients mandibular third molar were unerupted  (38 & 48 both 20% each)   while 23% had unerupted maxillary third molar

( 18= 11% & 28= 12%). In one patient left maxillary second molar was un erupted and in one patients all mandibular incisors were unerupted.

Removable partial dentures were fabricated for 26 females and 32 males while 10 males and 4 females were provided conventional complete denture.  Fixed Prosthodontics treatment was provided to 15 patients (8 males and 7 females).

Due to financial constraints of patients, implant supported prosthesis was not provided to any patient. For 8% (4 males and 4 females), restorative procedures were provided and 5% (3 males 2 females) were referred to Orthodontics department. Twelve patients (4 females and 8 males) were referred to tooth/ teeth extraction who were also provided with prosthodontic treatment after extractions. Five patients were not provided with any prosthesis as these patients did not pursue further for prosthodontics treatment.

DISCUSSION

Treatment of ectodermal dysplasia requires multidisciplinary approach. Before initiation of Prosthodontics treatment it is better to consult other dental professional for various dental treatments require for ED patients before provision of dental prosthesis. Manuja et al 10 discussed a case report in which removable prostheses were provided after extraction of maxillary

Table 1: Treatment Options provided for Ectodermal Dysplasia patients

teeth. In our study, 25 patients were referred to various departments for other dental treatment before initiation of Prosthodontics treatment. For 8% (4 males and 4 females) restorative procedures were provided and 5% (3 males 2 females) were referred to Orthodontics department. Twelve patients (4 females and 8 males) were referred for tooth/ teeth extraction who were also provided with prosthodontic treatment after extractions.

Orthodontic help is required for ED patients in conditions like diastema, spacing or crowding, malocclusion, malpositioned teeth and un-erupted teeth. Rashid et al11discussed orthodontic treatment in a 16 year Pakistani male having congenital missing mandibular central incisors. In our study, 5% patients were referred for orthodontic treatment. In three patients space closure was had been done while in two patients space were created in anterior maxillary segment.

Prosthodontic treatment is final destination for ectodermal dysplasia patients. Various treatment options like removable, fixed or implant are available for such patients. Tarjan et al12 stressed that early prosthodontic treatment is beneficial in many ways by improving appearance, speech and mastication. They discussed case reports of two young boys with age of 3 year 11 month and 3 year 2 months, respectively, provided with removable dentures. In our study, youngest patient was 5 years of age who was provided with removable partial denture.

In this study removable prostheses were fabricated in most of the cases as they are easy to fabricate, require less time and with low cost which is major contributing factor for any medical or dental treatment in our society 3 . Removable prostheses were provided to 72% patients (42 male and 30 female). Partial over denture were provided to 8 patients while for remaining patients conventional removable partial denture were fabricated Youngest candidate for conventional complete denture in our study was 15 year old girl. Pavarina et al 6discussed a case of 18 year old man provided initially with removable partial denture followed by over lay removable partial denture

and composite restoration.  Pannu K and Singh BD 13 discussed a case of 7 year old Indian boy provided with complete denture.

In fixed prosthesis, different options like resinbonded bridge, conventional bridge and implant supported prosthesis are available. Conventional fixed prosthesis is indicated where edentulous span is short. It is esthetically better and stresses can be evenly distributed. Preparation of abutment teeth in patients of ED patients requires care to avoid any pulpal exposure 14, 15.

Fifteen patients (8 males and 7 females) in our study were treated with fixed prosthesis. All patients were provided conventional bridges and reshaping of canine into lateral incisor had been done in two cases.

Due to financial constraints of all patients, none of the patient was treated with implant supported prosthesis.

Demographic profile of all the patients were recorded, so that these patients can be recalled in future. Murdock et al discussed the financial impact on treatment of ED patients.They found that with provision of implant supported prosthesis, overall treat cost was markedly increased as compare to conventional dental treatment16.

Long term follow-up is required for most of the patients. This follow-up is mandatory not only for the evaluation of the prosthesis provided but also it enables prosthodontist to provide definitive prosthesis for such patients. Bergendal 17discussed a case of a girl suffering from  ED, where 20 years follow-up was carried out. At first visit she was 6 year old, initially removable denture was fabricated, then after orthodontic and surgical intervention and implant supported prosthesis was provided.

Prosthodontist can play a major role in oral rehabilitation of ED, provision of early treatment will markedly improve the esthetics and various functional activities of ectodermal dysplasia patients.

Our aim of this study is to obtain profile of ED patients as this will serve as a guideline for future needs for oral rehabilitation of ED patients. The results of this study can serve as baseline for further research in this regard.

CONCLUSION

Oral rehabilitation of ED patients by removable and fixed prosthesis will markedly improve the esthetic and functions like mastication and speech in such patients which in turn, improves self esteem as well. Early diagnosis will help such patients to provide early management which in turn will be beneficial for the patients. Special program should be formulated to increase awareness about ED among public in general and health care providers in specific.

REFERENCES

  1. Hickey AJ, Vergo TJ. Prosthetic treatments for patients with ectodermal dysplasia. J Prosthet Dent 2001; 86: 364-369.
  2. Dhanrajani PJ. Hypodontia: Etiology, clinical features and management. Quintessence Int 2002; 33: 294-302.
  3. Patel I M. Prosthodontic rehabilitation of a patient with partial anodontia: A clinical report. J Prosthet Dent 2002; 88: 132-134.
  4. Manuja N, Passi S, Pandit IK, Singh N. Management of a case of ectodermal dysplasia: a multidisciplinary approach. J Dent Child 2011; 78:107-110.
  5. Gupta S, Tyagi P. Prosthodontic management of anhidrotic ectodermal dysplasia. Indian J Dent Res 2011; 22:348-351.
  6. Pavarina AC, Machado AL, Vergani CE, Giampaolo ET. Overlay removable partial dentures for a patient with ectodermal dysplasia: A clinical report. J Prosthet Dent   2001; 86: 574-577.
  7. Bala M, Pathak A. Ectodermal dysplasia with true anodontia. J Oral Maxillofac Pathol. 2011; 15:244-246.
  8. Shigli A, Reddy RV, Hugar SM, Deshpande D. Hypohidrotic ectodermal dysplasia: A unique approach to esthetic and prosthetic management: A case report. J Indian Soc Pedod Prev Dent 2005; 23: 31-34.
  9. Madhan R, Nayar S. Prosthetic rehabilitation of individuals with ectodermal dysplasia. Indian J Dent Res 2005 Jul-Sep; 16:114-118.
  10. Manuja N, Passi S, Pandit IK, Singh N. Management of a case of ectodermal dysplasia: A multidisciplinary approach. J Dent Child 2011; 78:107-110.
  11. Rashid S, Burki S, Bashir U. Orthodontic management option of congenitally missing mandibular central incisors (A case report), Pak Oral Dent J 2002; 22: 19-24.
  12.  Tarjan I, Gabris K, Rozsa N. Early prosthetic treatment of patients with ectodermal dysplasia: A clinical report. J Prosthet Dent 2005; 93: 419-424.
  13. Pannu K, Singh BD. Ectodermal dysplasia with total anodontia; A rehabilitation of a seven year old child. J Indian Soc Pedod Prev Dent 2002; 20: 114-117.
  14. Hemings K, Harrington Z. Replacement of missingteeth with fixed prostheses. Dent Update 2004; 31: 137-141.
  15. Forgie AH, Thind BS, Larmour CJ, Mossey PA,Stirrups DR. Management of hypodontia: Restorative considerations. Part III. Quintessence Int 2005; 36: 437-445.
  16. Murdock S, Lee JY, Gukes A, Wright JT. A costanalysis of dental treatment for ectodermal dysplasia. J Am Dent Assoc 2005; 136: 1273-1276. 17) Bergendal B. Prosthetic hablitation of a young patient with hypohidrotic ectodermal dysplasia and oligodontia: A case report of 20 years of treatment. Int J Prosthodont 2001;14:1-9.

  1. Current Status: Incharge Prosthodontics Department, Hamdard College of Medicine & Dentistry, Karachi.
    E-mail Address: mhussain26@hotmail.com Contact No: 0334-3728729
    Corresponding Address: House No. A-695, Block H, Northnazimabad, Karachi
  2. Current Status: Head Prosthodontics Department & Dean Post Graduate Studies, Fatima Memorial College of Medicine & Dentistry, Lahore.
    E-mail Address: nazia508@gmail.com Contact No: 0333-4317508
    Corresponding Address: House No: 508, Shadman Town, Lahore
  3. Current Status: Assistant Professor, Head Department of Periodontology, Hamdard College of Medicine & Dentistry, Karachi
    E-mail Address: imran121170@hotmail.com Contact No: 0303-2655762
    Corresponding Address: Department of Periodontology, Hamdard University Dental Hospital, Street No: 02, Block L, Northnazimabad , Karachi.

 

 

 

Replacing Existing Dentures By Copy-Denture Technique For Geriatric Patients: A Case Report

 

Syed Rashid Habib1                 BDS, FCPS

Fahim Ahmed Vohra2            B.D.S, MFDS, MClinDent, MRD RCS

Patients requesting replacement complete dentures have often worn the same set of dentures, successfully for many years. They have become accustomed with the fitting, polished and occlusal surfaces of their dentures. Patients should be provided with prosthesis which optimize esthetics, phonetics and function along with preserving the health of existing oral structures. Physical and mental adaptability of patients is of utmost importance in achieving success in complete denture therapy. This case report presents a method of complete denture fabrication along with its clinical and laboratory steps, which involve replicating the desired features of the prosthesis, along with improvements in esthetic, occlusion and stability, utilizing a three visit copy denture technique.

KEY WORDS: Copy denture, Existing dentures Replacing Techique Geriatric patiant.

HOW TO CITE: Vohra FA, Habib SR. Copy denture, Existing dentures Replacing Techique Geriatric patiant. J Pak Dent Assoc 2013;

INTRODUCTION

O The treatment of patients who need complete dentures, challenges the skills of a dentist. One concern is the clinical and technical aspect of denture fabrication; the other is the general physical health, local oral factors and psychological well being of the patient. These latter factors can be as important as the clinical and technical treatment aspects in the potential success of treatment1-4. The increased life expectancy of the elderly edentulous population augments the challenge of restoring mastication, phonetics and esthetics for these patients 5.

Dissatisfaction with complete dentures is a common phenomenon, Van Waas and others have reported that 25% of denture wearers have severe problems with their dentures6,7. Complaints about discomfort and instability often occur and many denture wearers report difficulties during mastication and phonetics8. With the advancements in techniques and materials, and the introduction of the implant supported prosthesis, the satisfaction level of edentulous patients with their prosthesis has increased9. However, a great challenge to the clinician is to make a decision in providing the patient with a conventional complete denture which is simple, quick and less challenging clinically and technically or to provide implant retained dentures which require increased cost, time and maintenance. Provision of a replacement complete denture to an elderly complete denture wearer is one of these challenges faced by a treating dentist10.

Adaptation to replacement dentures is a continuous struggle for the elderly especially, when major changes are made on the occlusal and fitting denture surfaces 11. The patients which pose the greatest threat are the ones with systemic disorders such as Parkinson’s, dementia and physically frail. A clinician must appreciate that the degree of adaptive capability of old denture wearers is also related to the health of the supporting tissues, their neuromuscular coordination, and their motivation for learning new skills12,13. Patient with old and inadequate prosthesis are still able to persevere with them due to muscular control developed over a long period. However, a new prosthesis requires the development of a new learning sequence and the will to be persistent. Therefore, it is important to identify patients who may have difficulty adapting or are

unwilling to learn new skills14, 15. In these cases, existing dentures are extremely valuable for diagnosis and treatment planning. Most existing dentures, whether or not they have been worn successfully, provide extremely valuable information for all stages of treatment16. These

patients will benefit from treatment that makes minimum change from the old to new dentures, such as the use of the Copy (duplicate) Denture technique because it makes an easier transition to the new prosthesis15-17. Copy dentures enhance neuromuscular adaptation to new dentures, reduce patient-clinician chair side time, reduce laboratory steps, require fewer patient visits, make jaw relation registration simple, provide technical staff with more guidance to tooth position and moulds, allows for copying esthetics and are cost effective18,19. Since the desirability of copying was recognized by Fenn et al in 1953, several methods have been evolved, most of which are based upon the production of replica dentures from impressions of the existing appliances to form the basis of the new appliances4,15-18, 20-21, 23-24. There is evidence to suggest that both the dentist and the dental technician have a clear understanding of the rationale behind the copy technique and why the technique is being used for a particular patient; it is likely that the prescription will not be followed accurately by the dental laboratory21.

This case report presents a method of complete denture fabrication along with its clinical and laboratory steps, which involves replicating the desired features of the prosthesis along with improvements in esthetic, occlusion and stability utilizing a three visit copy denture technique.

CASE REPORT

An 83 yr old male, reported to the Department of Prosthodontics, (Study setting removed). The patient was a complete denture wearer, using the existing dentures for the last 14 yrs. He complained of loose, discolored dentures and had difficulty in mastication. The patient was medically fit and well. Extra oral examination showed decrease in occlusal vertical dimension (OVD). In the intraoral examination the oral and denture hygiene was found to be satisfactory. The upper arch was U shaped while the lower arch was highly resorbed and depressed (Figure1). Due to

Figure 1. Intraoral views of the maxillary and mandibular arches.

resorption in the lower arch the bellies of mentalis muscle were very prominent. There was no intraoral

Figure 2. Existing (old) dentures of the patient.

pathology and adequate salivary flow was present. Inspection of the previous dentures exhibited discoloration and worn occlusal surfaces (Figure2). Denture examination exhibited lack of retention and stability, non-balanced occlusal contacts, worn teeth resulting in reduced occlusal-vertical dimension (OVD). A diagnosis of ill-fitting, discolored complete dentures with occlusal wear, decreased OVD and occlusal disharmony was made.

The treatment options available were:

4 Provision of new complete dentures fabricated by conventional denture fabrication technique. 4 Provision of new complete dentures fabricated by copy denture technique.

4 Implant supported over-dentures.

The objective was to provide new retentive and stable complete maxillary and mandibular dentures with acceptable function and esthetics with limited patient visits. The age of the patient and the relatively better evidence of the adaptation to the existing complete dentures was a clear indication for the use of copy denture technique. All options including their risks, benefits etc

were explained to the patient and the patient opted for new complete dentures by the copy denture technique.

The treatment was planned in three stages. At the first visit, impressions of the existing dentures were recorded using stock impression trays and irreversible hydro-colloid (alginate) for fabrication of the template dentures. Initially, the occlusal and polished surfaces of the dentures were embedded in the alginate mix, once complete set was achieved; grooves were cut

Figure 3. Moulds of the existing dentures after impression with alginate.

within the impression before the placement of the second tray. The fitting surface was then invested in a second mix of alginate and allowed to set undisturbed and stationary. Later, impression trays were separated and the dentures were recovered from their moulds (Figure3).  Subsequently, in the clinic, after cutting sprue channels (Inlet & Exit), a thin mix of the pouring type chemically curing acrylic resin was poured into the moulds (recorded impressions for the old dentures earlier). Two halves (impression of the polished/occlusal and

Figure 4. Acrylic resin replicas/copy templates made by pouring mix of cold-curing resin in the alginate moulds.

impression surface) of the moulds were secured with the help of grooves and rubber bands. After setting of the resin the template dentures (self cure dentures in pink color) were then removed from the moulds (Figure4).

The acrylic template replica dentures were then used for corrections in the maxillo-mandibular relations. In the first place the changes in the occlusal vertical dimensions were made. This was followed by registering the retruded position of the mandible and the face bow transfer record.  Before the original dentures were returned to the patient, shade of the existing denture teeth were recorded and the patient was discharged for the day.

Using the new maxilla-mandibular records, the replica dentures were mounted in the articulator with the face bow record and inter-occlusal centric relation record in wax (wax wafer) as recorded earlier (Figure 5). Arrangement of teeth was then carried out

Figure 5. Mounted copy templates using face-bow and centric relation record.

in the laboratory by removing acrylic resin and replacing with a tooth, one tooth at a time, without disturbing the buccolingual position of the teeth (Figure6).

Figure 6. Arrangement of Teeth On Copy Templates

At the second clinical visit, the trial of the dentures was done and functional reline impressions were recorded in the trial dentures using zinc oxide paste (Figure7). Investing of the denture in flasks, de-waxing,

Figure 7. Reline impressions recorded at the trial dentures stage.

packing the mould with resin and curing of the dentures was then completed in the laboratory. After finishing and polishing the dentures were ready for insertion (Figures 8 & 9).

In the third and final visit the dentures were fitted intra-orally after minor adjustments. The patient was

Figure 8. Finished and polished dentures.

Figure 9. Impression surfaces of new dentures.

called for review and follow up visit at 24 hours postoperative and after 1 week. During the follow up visits the patient was found to be satisfied with the function,

esthetics, occlusion and phonetics of the new dentures. This method is simple and utilizes materials and

Table 1: Clinical and Laboratory procedures at each Visit.

equipment commonly available in almost all dental surgeries20.

The various clinical and technical stages of a copy denture technique are summarized in Table-I. It is possible to undertake more than one clinical stage at the same appointment.

DISCUSSION

Provision of replacement complete dentures for an increasingly elderly population presents problems for the prosthodontist. This is due to reduced adaptability to new prosthesis because of decreased neuromuscular skills in geriatric patients22. The existing denture that needs to be replaced due to wear, tooth loss, discoloration, chipped and cracked bases provides the dentist with many useful information in planning new dentures. It is therefore helpful to reproduce familiar features of a patient’s old prosthesis, especially if these have been used successfully for some years23-26. With replacement dentures, copying of suitable features using a copy denture technique is indicated24. The existing denture provides superior trays and registration of maxilla-mandibular relations are easy and more predicable in terms of accuracy. With copy dentures information available in the patients existing dentures is used to simplify and quicken the procedure of making new dentures23-24. A local publication of a case report has described the benefits of the copy dentures and a technique of using copy denture flask specifically designed for duplicating existing dentures24. This techniques of obtaining replica dentures from the moulds of existing denture obtained in laboratory alginate or laboratory silicone as a duplicating material in copy denture flasks as described by Basker and Davenport20 and Ghani24 is widely employed all over the world. However, in case, these denture duplicating flasks are not available, then the trays technique and method may be used for obtaining the replicas of the existing denture as is the case in the present study.

The current case presented is a classical example of fabrication of the replacement dentures by the copy denture technique. Also, at the treatment option discussion, the patient wanted minor modifications within the existing dentures for improved comfort and function. Implant retained over-denture was not feasible for the patient due to high cost and surgical morbidity (advanced resorption). Relining was not suitable due to history of previous failed attempts and existing denture problems like, discoloration, flat occlusal surfaces and unstable dentures. All of these issues led to the indication of new replacement complete dentures with copy technique. This technique helped to reduce the patient’s clinical chair-side time as well as the reduction in appointments. With the new teeth there was improvement in the esthetics as well as chewing efficiency, and reduced OVD was improved with the new jaw relation record. Finally, well fitting new complete dentures was a direct result of the new impression surfaces.

The clinical value of a copy denture method enabling reproduction of selected features of old dentures compared to fabrication of new complete dentures in replacements is no longer in doubt26. The success of the present and earlier methods using copy technique in overcoming problems arising from disparities between new and old dentures constitutes a powerful argument for more widespread application of such a method as first line of treatment for appropriate indications22-26.

CONCLUSION

For elderly and frail patients who have used their old dentures successfully for a significant period of time, provision of replacement complete dentures by copy denture technique is a simple and cost effective procedure. The replacement dentures will have better adaptability with reduced chair-side and laboratory time.

REFERENCES

  1. Laird WR, McLaughlin EA. Management and treatment planning for the elderly edentulous patient.Int J Prosthodont 1989; 2: 347-351.
  2. Vervoorn JM, Duinkerke AS, Luteijn F, van de Poel AC. Relative importance of psychologic factors in denture satisfaction. Community Dent Oral Epidemiol 1991; 19: 45-47.
  3. Moltzer G, Van der Meulen MJ, Verheij H. Psychological characteristics of dissatisfied denture patients.Community Dent Oral Epidemiol 1996; 24: 52-55.
  4. Lindquist T J, Ettinger R L. Patient management and decision making in complete denture fabrication using a duplicate denture procedure: A clinical report. J Prosthet Dent 1999; 82: 499-503.
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  9. Esfandiari S, Lund JP, Penrod JR, Savard A, Thomason JM, Feine JS. Gerodontology. Implant overdentures for edentulous elders: study of patient preference. 2009 Mar; 26(1):3-10. doi: 10.1111/j.1741-2358.2008.00237.x. Epub 2008 May 20.
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  11. MacEntee MI. The effects of aging on the edentulous state. Prosthodontic treatment for edentulous patients. 12th ed. New Delhi. 2004; 03-05.
  12. Ettinger RL. Managing and treating the atrophic mandible. J Am Dent Assoc 1993; 124: 234-241.
  13. Hunt RJ, Beck JD, Lemke JH, Kohout FJ, Wallace RB. Edentulism and oral health problems among elderly rural lowans: the lowa 65+ rural health study. Am J Public Health 1985; 75: 177-181.
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  16. Sprigg RH. Diagnostic procedures using the patient’s existing dentures. J Prosthet Dent. 1983 Feb;49:153-61. 17
  17. Lindquist T, Narhi TO, Ettinger RL. Denture duplication technique with alternative materials. J Prosthet Dent 1997; 77: 97-98.
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  19. Paterson AJ. Removable Prosthodontics. In: Churchill’s Pocket Book of Clinical Dentistry. 2nd ed. London. Elsevier. 2002; 201-260.
  20. Basker RM, Davenport JC. Relevance of existing dentures. In: Prosthetic treatment of the Edentulous Patient. 4th ed. Cornwall. Blackwell Publishing Company. 2002; 97-122
  21. Kippax A, Watson CJ, Basker RM, Pentland JE. How well are complete dentures copied? Br Dent J. 1998 Aug 8;185:129-133.
  22. Jorgensen EB. Prosthodontic considerations in geriatric dentistry. In: A text book of oral gerodontology. 1st ed. Maryland. Publisher. 1981; 321-338.
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  24. Ghani F. The provision of new complete dentures by duplicating the existing plates. Report of a case. Pakistan Oral & Dental Journal 1992; 13: 29-34.
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  26. Habib SR, Azad AA. Comparison of patient’s satisfaction with replacement complete dentures fabricated by copy denture technique versus conventional technique. J Pak Dent Assoc. 2009; 18: 9-13.

    1. Assistant Professor, Department of Prosthetic Dental Sciences.
    2. Assistant Professor, Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University.

P. O. Box 60169, King Abdullah Road, Riyadh, 11545,
Saudi Arabia Office: 966-1-467 7444 Mobile: 966-532911056
Fax: 966-1-467 8548

Pattern Of Dental Anomalies In Orthodontic Patients At A Tertiary Care Hospital

 

Meena Kumari Rathi1                 BDS, FCPS

Mubassar Fida2                             BDS, MCPS, FCPS, PGD HIMS

OBJECTIVE:  The objectives of this study were to investigate the pattern of dental anomalies in orthodontic patients at the Aga Khan University Hospital and to find out the most frequently occurring dental anomaly.

METHODOLOGY: This was a descriptive study conducted at the dental clinic, the Aga Khan University Hospital, Karachi. The data was collected using pretreatment panoramic radiographs of orthodontic patients who presented at the dental clinic and a total of 570 patients who fulfilled our selection criteria were included in this study. On the pretreatment panoramic radiographs, following dental anomalies were noted: agenesis, supernumerary teeth, dilacerations and taurodontism.

RESULTS: Out of a total of 570 patients, dental anomalies were seen in 74 (12.9%) patients. Hypodontia was the most common finding, occurring in 39 (6.8%) patients with the lower second premolar being the most commonly missing tooth (28.2% of all missing teeth). Dilaceration was observed in 25 (4.3%), supernumerary teeth in 6 (1%) and taurodontism in 4 (0.7%) patients.

CONCLUSIONS: It was observed that about 13% of patients showed at least one dental anomaly. Hypodontia was the most common anomaly while taurodontism was the least frequently seen anomaly.

KEY WORDS: Panoramic radiographs, hypodontia, supernumerary, dilaceration, taurodontism.

HOW TO CITE:  Rathi MK, Fida M. Pattern of Dental Anomalies in Orthodontic Patients at a tertiary Care Hospital. J Pak Dent Assoc 2013; 22: 226-228.

INTRODUCTION

Dental anomaly is defined as an abnormality in which a tooth or teeth have deviated from normal in form, function, or position. Any variation in tooth number, shape and size can affect the maxillary and mandibular arches and occlusion, which may complicate treatment planning1 .The occurrence of multiple abnormalities involving single or groups of teeth may be genetically determined and can be associated with specific syndromes. However most anomalies arise sporadically and some involving shape and size may be affected by environmental factors acting during the morphodifferentiation stage of tooth formation2. There are thousands of anomalies that can be identified but certain anomalies are more common than others3.

Agenesis or missing teeth are commonly observed and three terms are used in their description: Hypodontia is developmental absence of less than six teeth, oligodontia is developmental absence of six or more teeth and anodontia denotes developmental absence of all teeth4. As far as etiology is concerned, it is a multifactorial condition with genetic and environmental influences. Recent advances in molecular genetics have established the importance of different mutations in two transcription factors i.e. MSX1 and PAX9, in dental development4. Familial tooth agenesis follows an autosomal dominant pattern5. The most commonly missing teeth are the third molars followed by mandibular 2nd premolars and then maxillary lateral incisors6. Missing teeth can be a real challenge for both orthodontists and restorative dentists. Supernumerary teeth are another commonly seen dental anomaly. These are the extra teeth that occur in addition to the normal series and may arise due to dichotomy of a tooth bud; however the most acceptable cause is localized independent hyperactivity of the dental lamina7. They may occur in any region with a predilection for premaxilla and the most common being the mesiodens in the maxillary midline. Treatment depends on the type and position of the supernumerary tooth and on its effect on adjacent teeth.

Taurodontism, also called bull-like teeth, is defined as the apical extension of pulp chamber below cementoenamel junction resulting in proportionately shortened root and lengthened crown and with the bifurcation of root more apical1. Molars are generally affected with taurodontism.

Dilaceration is a sharp bend or angulation of the crown or root portion of tooth. It typically occurs secondary to trauma to

its primary predecessors during formation of the tooth, but it may be idiopathic as well. The dilacerations of the root is more common than that of the crown.

These anomalies can be observed on panoramic radiographs which are one of the commonly requested radiographic

examinations8. Orthodontists frequently use these radiographs to diagnose malocclusion, plan treatment and assess progress and achievement of treatment goals. An orthodontist should be aware of the potential of presence of pathology in their patients and can expect to discover anomalies on radiographs. The present study was conducted to investigate the pattern of dental anomalies like congenitally missing teeth, supernumerary teeth, dilacerations and taurodontism and to find out the most frequently occurring ones on the panoramic radiographs of orthodontic patients at the Aga Khan University Hospital.

METHODOLOGY

This was a retrospective study which was carried out using pretreatment panoramic radiographs of orthodontic patients who visited the dental clinic at the Aga Khan University Hospital, Karachi. Panoramic radiographs of 570 patients, who met our selection criteria, were retrieved. The inclusion criteria were (1) availability of pretreatment panoramic radiographs (2) no history of extraction of any permanent tooth prior to orthodontic treatment (3) no history of trauma and (4) no significant medical history. The exclusion criteria adopted were (1) third molars (2) patients with craniofacial anomalies or syndromes and (3) teeth with incomplete root formation.

Analysis of the panoramic radiographs was done through direct observation over an illuminator by a single investigator. On the pretreatment panoramic radiographs, following dental anomalies were noted: agenesis, supernumerary teeth, taurodontism and dilaceration. Data was pooled and analysed for frequency, gender and tooth type involved.

RESULTS

Out of a total of 570 patients, dental anomalies were seen in 74 patients (12.9%), with 39 of them being females (52.7%) and 35 being males (47.2%). The age range was 10-26 years with a mean age of 15.8 years (S.D ± 4.45).  Table I shows the frequencies of various anomalies, while Table II shows their gender distribution.

The most commonly seen anomaly in the study sample was congenitally missing teeth. It accounted for 6.8% of the total patients (20 females and 19 males) and 52.7% of the total anomalies seen. The mandibular second premolar was found

Table I: Frequency of various anomalies
Table II: Gender distribution of various anomalies

missing in 11 cases and hence it was the most commonly missing tooth (28.2%) followed by maxillary lateral incisor which was missing in 10 cases (25.6%), as shown in Fig 1. These were

Fig 1: Graphic representation of frequency of missing teeth

followed by lower central incisors which were absent in 6 cases (8.1%). Regarding the number of missing teeth per individual, it was found that 16 patients (41%) presented with one missing tooth, 16 patients (41%) with 2 missing teeth, one patient (2.5%) with 5 missing teeth, one patient (2.5%) with 15 and one patient (2.5%) was seen with 18 missing teeth.

Fig 2: Graphic representation of frequency of supernumerary teeth

Supernumerary teeth were found in 6 patients (1% of the sample) comprising of 2 females and 4 males. Four patients (80%) presented with mesiodens and two (33%) with supplemental teeth (Fig 2).

Dilacerations were recorded in 25 patients (4.3% of the sample) comprising of 15 females and 10 males. The total number of dilacerated teeth was 44. The mandibular 2nd  molar was the most commonly affected tooth, occurring in 15.9% of the dilacerated teeth, followed by  maxillary 2nd premolar (9%), as shown in Fig 3. Fourteen patients (56%) had only one tooth each with dilacerated roots, 8 patients (32%) had 2, 2 patients (8%) reported with 3 and one patient (2.2%) with 7 dilacerated teeth.

L7: Lower 2nd molar L5: Lower 2nd premolar U5: Upper 2nd premolar U4: Upper first premolar L4: Lower 1st premolar Others: Upper central incisor, upper canine,upper 1st premolar and 2nd molar, lower 1st & 2nd premolar & lower 2nd molar

Fig 3: Graphic representation of frequency of dilacerated teeth

Fig 4: Graphic representation of frequency of taurodontism

Taurodontism was observed in 4 patients (0.7%) and the total number of teeth was 8. The majority of the teeth affected were mandibular 1st and 2nd molars (present in each of 3 patients), and each accounting for 28.5% of teeth involved in taurodontism. One patient presented with three maxillary teeth i.e. maxillary

1st and 2nd premolars and 1st molar, involved in taurodontism (Fig 4).

DISCUSSION

Approximately 2% to 10% of the populations have been shown to exhibit missing teeth 5, 9.  In the present study dental agenesis occurred at a frequency of 6.8% which is comparable with the finding of 8.1% by Thongudomporn1. The most frequent congenitally absent tooth, after the third molar, is the mandibular second premolar. It was found missing in 2.5% to 4% of the population and was bilaterally absent 60% of the time and this

Table III: Hypodontia prevalence studies in different countries

is followed by absence of maxillary lateral incisor6. In our study mandibular 2nd premolars were missing in majority of the cases. Contrary, a study by Kennedy9 showed maxillary lateral incisor as the most commonly missing tooth. Hence it has been observed that the frequency of missing mandibular second premolars, maxillary lateral incisors and maxillary second premolars varies with the population investigated10, as can be seen in Table III. It has been observed that most individuals lack only one or two permanent teeth 5,9 and this coincides with our study which showed that most of the patients had one or two missing teeth. Two patients presented with oligodontia with 18 and 15 missing teeth each and there was one patient who reported with five missing teeth.

The frequency of supernumerary teeth was 1% which is in the range of other studies like that of Thongudomporn1, Basdra11 and Yousof12. Thongudomporn2 found 1.8 % supernumerary teeth in a sample of Australian population. According to Basdra11, the occurrence of supernumerary teeth in general Caucasian population ranges from 0.1% – 3.8% in the permanent dentition and 0.3% – 0.8% in primary dentition. Scheiner13 observed most frequent supernumerary teeth in anterior maxillary region followed by mandibular premolar region. Our findings are consisted with this study as all our supernumerary teeth (4 mesiodens and 2 supplemental lateral incisor) are found in anterior maxillary region.

Hamasha et al14 recorded prevalence of dilacerations in 3.7% of the teeth examined. In his study he found the most commonly affected teeth were mandibular first molars (5.6%) after the mandibular third molar teeth. This is in contrast to our study in which mandibular second molar is the most affected tooth with dilacerated roots. Root dilacerations occurring in mesial or distal directions are clearly noticed on panoramic radiographs but those that occur in labial and lingual directions cannot be detected on these radiographs. For the detection of these types of anomalies, additional radiographs from different angles will be useful 2 .

Darwazeh15 reported taurodontism in 8% of subjects and 4.4% of the teeth examined and found that maxillary second molar was the most commonly affected tooth. However in our study where taurodontism was seen in 0.7% of patients, the majority of cases were also of mandibular 1st and 2nd molars. A higher frequency (46.4%) of taurodontism has been reported by MacDonald-Jankowski and Li16 in adult Chinese population. The difference might arise from differences in diagnostic criteria or due to racial variations. The precise diagnosis of taurodontism from panoramic radiographs is difficult because molar areas usually appear distorted and may result in incorrect diagnosis and therefore supplementary radiographs are essential to confirm taurodontism2.

CONCLUSION

It was found that about 13% of orthodontic patients at The Aga Khan University Hospital showed at least one dental anomaly.

‘Congenitally missing teeth’ was the most common anomaly

(6.8%) and taurodontism was the least frequently seen anomaly (0.7%) in our orthodontic patients. The orthodontists have the responsibility to have full knowledge of these anomalies as these may have treatment planning and/or treatment execution complications for orthodontic patients.

REFERENCES

  1. Thongudomporn U, Freer TJ. Prevalence of dental anomalies in orthodontic patients. Aus Den Jour 1998; 43: 395-398.
  2. Lorena SC. Multiple dental anomalies. J Oral Sci 2003; 45: 47-50.Kuhlberg AJ, Norton LA. Pathologic findings in orthodontic radiographic images. Am J Orthod Dentofacial Orthop 2003; 123: 182-184.
  3. Arte S, Pirinen S. Hypodontia. Orphanet encyclopedia. May 2004: http://www.orpha.net/data/patho/GB/uk-hypodontia.pdf
  4. Vastardis H. The genetics of human tooth agenesis: New discoveries for understanding dental anomalies. Am J Orthod Dentofacial Orthop 2000; 117: 650-656.
  5. Casey DF. Congenitally missing mandibular second premolar: Treatment outcome with orthodontic space closure. Am J Orthod Dentofacial Orthop 2003; 123: 676-682.
  6. Rajab LD. Supernumerary teeth. A review of literature. Int J Paed Dent 2002; 12: 244-254.
  7. Bondemark L, Jeppsson M, Ingildsen LL. Incidental findings on panoramic and abnormality in pretreatment orthodontic panoramic radiographs. Angle Orthod 2006; 76: 98-102.
  8. Kennedy DB. Orthodontic management of missing teeth. J Can Dent Assoc 1999; 65: 548-550.
  9. Larmour CJ. Hypodontia – A retrospective review of prevalence and etiology. Part 1. Quintessence Int 2005; 36: 263-270.
  10. Basdra EK. Supernumerary teeth: Incidence, Morphology, Etiology. J Orofac Orthop 1997; 58: 144-153.
  11. Yousof WZ. Non-syndromal multiple supernumerary teeth: Literature Review. J Can Dent Assoc 1990; 56: 147-149.
  12. Scheiner MA. Supernumerary teeth. A review of literature and four case reports. Aus Den Jour 1997; 47: 160-165.
  13. Hamasha AA, Al Khateeb AL, Darwazeh AM. Prevalence of dilacerations in Jordanian Adults. Int Endod J 2002; 35: 910-912.
  14. Darwazeh AM. Prevalence of taurodontism in Jordanian dental patients. Dentomaxillofac Radiol 1998; 27: 163-165.
  15. MacDonald- Jankowski DS, Li TTL. Taurodontism in a young adult Chinese population. Dentomaxillofac Radiol 1993;22: 140-144.

    1. Assistant Professor, Head of Orthodontics Department Jinnah Medical and Dental College, Karachi.
    2. Associate Professor, Programme Director Orthodontics Section of Dentistry, Dept. of Surgery. The Aga Khan University Hospital, Stadium Road, Karachi
    Correspondence to:“Dr. Meena Kumari Rathi” <mk_das@hotmail.com>

Orthodontic Special Cases Best Treated With Simple Indirect Bonding Protocol

 

Shazia Naser-ud-Din1                     PhD, MSc, BDS, DPHDent, FICCDE, DCPSP-HPE

Brisbane School of Dentistry

Orthodontic treatment methodology has evolved considerably in the past few decades and much of technological advances are definitely improving the efficiency and delivery of orthodontic treatment, but come at a higher cost. One such example is the commercial indirect bonding.

In certain orthodontic cases with special needs indirect bonding (IDB)  is not a luxury but a necessity and should be considered . The additional cost can be eliminated by simple chairside technique that  can be applied with success. The aim of this  paper is to discuss an orthodontic case where IDB was used to successfully complete the case in shortest possible treatment time and secondly the methodology employed – The Brisbane Orthodontics IDB Protocol.

KEYWORDS: Special cases orthodontic, Simple Indirect Bonding.

HOW TO CITE: Naser.ud.Din S. Orthodontic Special Cases Best treated with Simple Indirect Bonding Protocol. J Pak Dent Assoc 2013; 22: 251-254.

INTRODUCTION

Indirect bonding (IDB) even though has been introduced for over 3 decades is underutilized1. It has several benefits however the added cost and time to deliver the transfer trays has deterred many Orthodontists to establish it as a routine in practice. Commercial costs are generally excessive and cost benefit ratios low for the clinic. However, many Orthodontists are devising simple clinic procedures that would allow easy application of indirect bonding2. Most important aspect of IDB is for those who benefit from less chair time such as medically compromised cases like ADHD (Attention Deficient Hyperactivity Disorder), Cerebral Palsy, CLP (Cleft Lip and Palate)  and sailorrhoea cases to name just a few. New techniques for IDB are continuously evolving. Numerous methodologies have been cited.  Historical methodologies cited in the literature are the Thomas3 and Hickham4 techniques, the flexible undertray by Moskowitz et al5 and the contemporary Sondhi technique using 3M-Unitek APC brackets6 and adhesives which need to be chemically cured and have a relatively short working time.

In this paper a clinical case that was treated with IDB from the protocol adopted at the Brisbane school of Dentistry is show cased for efficiency of treatment and minimal finishing requirements due to precision of bracket positioning by indirect bonding method. Secondly, IDB protocol is discussed in detail for interested readers to apply in their own clinical set up.

DISUSSION

A young male patient aged 12 years was referred by a school dentist due to insufficient space for the eruption of 13, 23. He also had ADHD diagnosed since the age of four, and was on regular medications (Retalin® daily) and the mother reported low pain threshold. Habit of nail biting was evident too.

Fig. No. 1

As he suffered from ADHD (Attention Deficit Hyperactive Disorder) was anxious in the chair and did not like sitting still for too long. This affected the initial consult (hence poor quality intra oral photographs). However, over a period of time he did acclimatize to us and was very friendly and open. Special precautions were made such as first appointments in the session so that there was no waiting period that could aggravate the anxiousness. Secondly indirect bonding (Brisbane Orthodontics protocol) was done to reduce the chair side time at the bond up appointment. Such measures not only enhanced patient cooperation but ensure efficient treatment due to less wire bending in finishing stages.

He had mild skeletal II base with average facial proportions. At the time of examination presented in late mixed dentition with moderate maxillary and mandibular crowding and Class I molar relationship bilaterally. On expressive smiling 1mm of gingival show with upper midline 1mm to the right and lower 2mm to the left due to labially excluded 33 in the mandibular arch. Radiographic examination revealed potentially impacted 13 in sector 1 and 23 in sector 3 placed within the line of the arch. 27 eruption was obstructed by a developing tooth follicle – which could be odontome or the ectopic 28.

The aim was to keep the treatment time to the minimum with least number of visits. Hence, nonextraction treatment with 0.022×0.028” slot MBT (Victory Brackets) were placed by Indirect bonding protocol  to save chairside time and alleviate anxiety in the patient.

On previous appointment, impressions with molar bands in situ were taken for fabrication of TPA (Trans Palatal Arch).  Total treatment time was 18 months, primarily due to the delayed eruption of bilateral upper permanent canines. Number of visits and summary is provided in the table.

The pretreatment weighted PAR was 28 and post treatment 0, with 100% improvement. Both patient and mother were thoroughly satisfied with the treatment. It was indeed gratifying to see him settle well into our clinic through the treatment duration.

Fig. No. 2

Impacted canines need attention as when space is deficient it retards the eruption or completely prevents it. In the latter case it may lead to cystic changes over a period of time. With growth potential on our side resulting in shorter treatment time.  Non-extraction treatment was possible as the patient was in active pubertal growth spurt.

Although there was crowding, extractions of upper first premolars would provide the space for upper canines. However, that would lead to excessive space with anchorage burning and Class II molar relationship not the ideal scenario. Not to mention it would prolong the treatment time and every effort was made to keep the treatment time shortest possible and least complicated treatment methodology (medical history).

Generally assisting impacted canines into the arch is anchorage demanding. Simple TPA would reinforce the anteroposterior anchorage to maintain class I molar relationship. TPA was removed after alignment of 13, 23. TPA is more user friendly as compared to Nance button or the head gear in the experience of the author.

IDB  Brisbane Orthodontics Protocol

Indirect Bonding (IDB) Brisbane Orthodontics Protocol has fewer steps with cost effective materials. Low failure rate leads to predictable results. Steps to be followed to ensure success  are as follows: 1. Use high quality recent alginate impressions of upper and lower arches poured immediately in cast plaster stone (colour contrast preferred for aesthetic brackets). The casts should be free of voids and bubbles. Use brackets of choice onto the plaster model with UHU stick( G m b H & C o ,B ü h l ,Germany).Apply sparingly on the base and attach to the predetermined long axis position at the centre of the clinical crown (Fig 3). Let it dry for couple of hours. The UHU adhesive is viscous and allowsfor placement of the bracket with no drift. Clear PVS (PolyVinylSilicate)-Memosil* is applied evenly over the model (Fig 4). The PVS should extend for a few millimetres all around the brackets and conformed into a transfer tray. Memosil* has a relatively short working time which can be extended by refrigerating prior to use. Fingers dipped into soapy water allow the tacky material to be molded over the arch easily. Let the tray set for 5 minutes. Soak in lukewarm water for 5 minutes

Fig. No. 4

to soften the adhesive. Peel it off like a banana peel from one end of the arch to the other with gentle pressure. Follow the path of least resistance and ensure that all brackets have successfully been transferred onto the tray. Immerse in warm water (Fig 5) for couple of minutes and wash off the UHU under running warm water or use a triplex to

Fig. No. 5

clear away any remaining glue. The bracket bases should now appear free of any residue.

Dry the tray and bracket bases thoroughly prior to bonding. Application of the composite adhesive is a “critical technique”. It is easy to apply excessive amounts of composite and be faced with a lengthy cleanup which is counter productive. Train your supporting staff for the protocol prior to the procedure.Firstly, apply a flowable bonding agent onto the bracket bases. Use Ortho Solo** as it has highest viscosity due to its increased filler content. Recent studies indicate that it produces high bond strength.7A small amount of bonding adhesive ( Transbond ***) is applied to the bracket base (Fig 6). Minimal adhesive is required. The Transbond™ is then lightly pressed onto the bracket with a microbrush dipped into Ortho Solo™ to ensure the bracket base is well covered and that

Fig. No. 6

the mesh base is engaged by the adhesive. 4. Pumice, etch, wash and isolate the teeth.  Place the tray avoiding excessive force as it may distort the tray and lead to inaccurate bracket placement. Immediately light cure ( Ortholux LED ****) for 12 seconds in the left and right posterior sections and in the mid anterior section ( Fig 7 ). Three point curing assists in stabilizing

Fig. No. 7

the tray after which the individual brackets can be cured for 12 seconds each without supporting the tray to ensure thorough curing. Peel off with similar maneuvers as on model ( Fig 8 ) or use  periodontal scaler to lift

Fig. No. 8

it off. If severe undercuts or rotations present, the tray can be sectioned in-situ to remove it with ease. Ensure no bonding has occurred interdentally by floss check. Excess bond may occasionally appear that can be removed with tungsten bur at chairside.

*Memosil™, HeraeusKulzer GmbH, 300 ,Heraeus Way, South Bend, IN 46614; www.heraeus-dental.de. **Ortho Solo™ (Ormco,, Sybron Dental Specialties, Orange, CA). *** Transbond XT ™  3M ESPE, St Paul, Minn USA. **** Ortholux™ Luminous curing light (3MU nitek, 2724 South Peck Road, Monrovia, CA 910 16 USA).

CONCLUSIONS

The Brisbane Orthodontics IDB protocol has been used successfully at the Postgraduate program at UQ since 2010. It allows a novice operator to be confident especially in the initial set ups. Hence, it is a vital teaching methodology where the operator can get a supervisor to correct bracket positions prior to placement in-situ. Among other advantages such as efficiency of time, cost effectiveness and reduced chairside time, the author has found its major utility with special need cases where bonding stage can be laborious and unpleasant experience for the patient. With University of Queensland tertiary care clinic special cases are seen more often and hence IDB has been valuable in treating such cases. The method is certainly technique sensitive and proper coordination with staff is essential for predictable successful results.

ACKNOWLEDGEMENTS

School of Dentistry, UQ is indebted to Brisbane Orthodontics, Queens Street Mall Brisbane, to provide the opportunity to introduce this protocol to the postgraduate program and for publication.

REFERENCES

  1. Keim RG, Gottlieb EL, Melson AH, et al. 2008 JCO study of orthodontic diagnosis and treatment procedures. Part 1. Result and trends.J Clin Orthod 2008;42:625-640.
  2. Qamruddin I, Ashraf B, Shahid F. Indirect boding with hot glue method.J Pak Dent Assoc 21 2012; 21:252-254.
  3. Thomas RG. Indirect bonding: simplicity in action.J Clin Orthod 1979;13:93-106.
  4. Hickham JH. Predictable indirect bonding. J Clin Orthod 1993;27:215-217.
  5. Moskowitz EM, Knight LD, Sheridan JJ, et al. A new look at indirect bonding. J Clin Orthod 1996; 30:277-281.
  6. Sondhi A. Efficient and effective indirect bonding. Am J Orthod Dentofacial Orthop 1999;115: 352-359.
  7. Wenger NA, Deacon S, Harradine NW. A randomized control clinical trial investigating orthodontic bond failure rates when using Orthosolo universal bond enhancer compared to a conventional bonding primer. J Orthod 2008;35:27-32.

School of Dentistry | The University of Queensland  200 Turbot Street, Brisbane QLD 4000 AUSTRALIA

P: +61 7  3365 8084   F: +61 7  3365 8199

Correspondence to:“Dr. Meena Kumari Rathi” <mk_das@hotmail.com>

Occlusion: Lost Art, Lost Discipline: Part ll

 

 

Harold M. Shavell1                         DDS, FADI, FICD, FACD, FAAED

 

Editors’ note: This article is part 2 on “Occlusion: Lost Art, Lost Discipline”

I’ve commented previously (in Part 1) that one must always begin with the final image (visualization, picture) in mind if one is to achieve a successful final result. Languagemay be satisfactory to explain details and technique,but it cannot adequately convey perception and visualization.Mental images rapidly dissipate when attempting to transform thoseimages into words; visual thinking dies the moment it must objectify the subjective and crate corporeal (ie, morphologic) reality. The trick is to be able to metamorphose imagery into corporeal reality. However, in those in whom the process is intact, or may even be blossoming, transmitting that ability becomes a moot point. It’s akin to ‘telling’ someone how to ride a bike; one has to develop that kinesthetic sense solely by participation. Similarly, morphology imaging is not a problem to be solved but an essential realism to be experienced, since every dentist will precipitate malocclusion to a greater or lesser extent with almost every restoration placed–mainly due to the inability to mentally perceive the existence of the odontomorphic “OCCLUSAL BALLET.”

The inability to envision, to mentally ‘see’ intercuspation as a Pas de Deux between form (morphology) and function (occlusion) is what keeps dentists from creatively and effectually addressing maxillo-mandibular dysharmony. The inability to image explains why the eye does not see what the mind has not taught it to recognize (Fig.4).Again: You have to ‘see’ there to ‘be’ there. Vision without action is fruitless, and action without vision is dangerous. Thinkers think and doers do, but until thinkers do and doers think, progress falters. Sadly, “I dreamed athousand new paths. I woke and walked my old one”. If there’s no ‘Occlusal Ballet’ playing before your eyes, the delicate occlusomorphic adagio begins to falter as cuspsbecome shorn while stumbling awkwardly over one another as form (morphology) and function (occlusion) ignominiously collide in jolting antagonism, sparking cumulative cuspal ricochet! The ingenuous, rather naïve choreography of what should have been a tranquil, arabesque cuspal ballet has instead ignited total gnathic war.

Time ripens all things. No man is born wise.

We should know the tops of teeth as well as Rubenstein knew the tops of piano keys. If most dentists cannot conceptually visualize and draw the teeth they attempt to repair, if they cannot mentally pictorialize morphologic form and draw teeth–how then are they able to properly sculpt restorations, fabricate provisiona restorations, critically analyze work returned from the laboratory, or correctly intercuspate and adjust an occlusion? “O, had I but followed then arts.” (Shakespeare). If the dentists cannot artfully control the morphology, evaluate, understand and properly adjust ongoing cuspal topographical changes, they therefore cannot clinically control the occlusion! Remember: morphology and occlusion are two sides of the same coin. To do easily what is difficult for others, is the mark of imaging talent. Of note once again is that visualization, and calling forth mental images allows that restorations are being carved with the mind, not with the hand—the hand simply being the facilitator. One must elevate such an ideation to a belief, and then acknowledge the fact that such a belief is not merely an idea the mind possesses; it is an idea that possesses the mind.

The aesthetics of occlusion—the ART OF OCCLUSION—represents an intricate, well-controlled, graceful balletic pavane between form and function. The dentist is the choreographer and the technologist is the ballet master. The treatment plan is the score, the provisional the rehearsal, and the porcelain is the actual performance. For example, when choreographing the ‘Occlusal Ballet’, this cusped corps d’elite, we establish that moving from ‘en pointe’ (centic position) to a lateral pas de deux movement (canine glissade/disclusion) is not an ensemble movement! The only teeth properly ‘performing’ individually in lateral movement are the canitnes, arguably assisted by select fellow performers (anterior teeth); choreographing ensemble (group) function ultimatelybegets ensemble (group) destruction. Shorn-cusped, amorphous ‘restorations’, aside from being ugly and difficult to keep from wearing away too rapidly, are unworthy of the skills the modern dentist can muster. If God wanted us to have flat teeth, he would have made us two-stomached, fourhoofed, tail-wagging herbivorous ungulates. (Fig. 4-A)

Fig. No. 4-A

It must be considered that the significance of occlusion in clinical reality has not received attention commensurate with its importance…especially as most people do not have perfect occlusions, and virtually all people have occlusal interferences. Regrettably, occlusal adjustment is the least used and most misunderstood form of treatment available for occlusally related disorders. Realistically,not a single facet is timid or safe. These are seemingly small coincidental ‘occurrences’ with huge consequences, as cusps struggle to escape their oppressors and their seemingly inevitable ablative fates. A facet is a functional and morphological occlusal design flaw. It is better to prevent the occurrence of facets than to ‘adjust’ them. The often misused term ‘occlusal adjustment’ is nothing more than a tour de ’farce’, more fraught than haute. Unfortunately, there is no universal agreement about the best way to perform occlusal adjustment, or which type of occlusal interference is considered to be the most detrimental to function.Stated most elementally,‘occlusal adjustment’ means the artful elimination of the unnecessary so that the necessary may speak.

I have been told that a young would-be composer wrote to Mozart asking advice about how to compose a symphony. Mozart responded that a symphony was a complex and demanding form and it would be better to start with something simpler. The young man protested, ‘But, Herr Mozart, you wrote symphonies when you were younger than I am now.’ Mozart replied, ‘I never had to ask how.’

reason. Continuous, conscientious, scrupulous, persevering effort–not strength or intelligence–is the key to unlocking our recondite imaging potential. It’s there in all of us–quietly, patiently waiting to be discovered. “Well done is better than well said” (Ben Franklin).

When we consciously make the mental shift to “LINGUOVISION”, it means being able to “view” the presenting clinical situation much as we would in the laboratory, when we turn the articulator around (You have to ‘see’ there to ‘be’ there !) and examine the occlusion from ‘behind’ (Fig 5).

Indisputably, imaging proper intercuspating morphologic form in this manner is the key to gaining the knowledge required to successfully (and esthetically!) treat problems arising in what is the quintessential common denominator in all dentistry–occlusion. Moreover, evaluating the ‘intercuspal ballet’ from the lingual perspective during laboratory fabrication is like viewing a performance of the “Élite Corps de Ballet” from ‘behind the curtain’; That’s Linguovision! Without any doubt it’sthe very best way to learn occlusion—

GUARANTEED!

Anyone who keeps the ability to see beauty never grows old.

Franz Kafka

‘Seeing’ via Linguovision, is really an enabling and facilitating visualization. It’s scannable articulation imagery. Mentally ‘lingualizing’ the occlusion is an invaluable aid–an amazingly useful tool–for understanding the basic “A,B,C’s” of Occlusodontology! Think of leisurely and artistically carving the fine morphologic details of a complex restoration with ease, as if you were actually copying a vivid mental picture which you had visualized specifically for that procedure! Or think of the facility with which you might dispatch that nagging occlusal imbalance, diagnose the maddening persistent occlusal wear problem, or identify the correct intra-oral tripodal contacts of a Class II malocclusion simply by calling forth in your mind’s eye the appropriate linguovision intercuspating morphology.

The most exciting place to discover and practice this ability, is in yourself!

However there are ‘fences’ which seem to always surround you, and they are all in your mind. The physical fences you think you may be surrounded by, in reality are the mental fences that hold you captive. How can you free yourself, and how can you stop being fencebound by negative thinking? Those so-called fences are never extrinsic. They’re always intrinsic, they live inside us. The antidote to being trapped by your own mental fences is to create a compelling enough vision such that you’re willing to resort to overwhelming measures to break out. Freedom, ultimately, is just on the other side of passionate, purposeful action. Always remember: The fences that seemingly surround you…are all in your mind! Our mental foibles may be best characterized by, of all things, a comic strip character called Pogo: “We have met the enemy, and he is us!

The ‘difficulty’ of the task is no excuse for avoidance; as such, we’ve all been admonished “Practice makes perfect”— and old aphorism which is generally misunderstood, and which now requires clarification in the context of this discussion. Deliberate practice, is a very special form of activity that differs from mere ‘experience’ and mindless drill. It is a discipline not inherently enjoyable. It does not involve a mere execution or repetition of already attained skills, but repeated attempts to reach beyondone’ current level…which is associated with frequent failures.It’s practice that doesn’t take no for an answer; practice that perseveres; the type of practice where the individual keeps raising the bar of what he or she considers success. This type of practice requires a constant self-critique, a pathological restlessness, a passion to aim consistently just beyond one’s capability. Failure and disappointment may occur daily, but there is a never-ending resolve to dust oneself off and try again and again and again. Every adversity, every failure, every headache carries with it the seed of an equal or greater benefit. It’s the kind of special, self-monitoring,intense kind of practice that forces your mind into the kind of change that is necessaryfor improvement.

Outstanding skill in any domain of human accomplishment—and morphologic occlusion is no exception—is rarely achieved without such disciplined dedication. John Keats opined, “Nothing ever becomes real ‘till it is experienced.” Simply put, we can’t just wish our way into skill and success; skill and success are not given—they have to be earned!

Every act of conscious learning requires the willingness to suffer an in jury to one’s self-esteem. That is why young children, before they are aware of their own self-importance, learn so easily; and why older persons, especially if vain or “important”, cannot learn at all.

Thomas Szas, MD, Prof. of Psychiatry

The real issue is not talent as an independent element, but talent in relationship to will, desire, tenacity, doggedness, inexhaustible grit, and indefatigable persistence. Staunch, unwavering, principled purpose elevates what we do. Only the mediocre are always at their ‘best’. Remember, we are what we do every day! Are you willing to experience the above-mentioned rigors of ‘deliberate practice’ to move to a higher level of accomplishment? Do YOU possess the passion?

It should be made clear that the study of occlusion is not the study of an accurate science. It requires knowledge, experience, creative imaging, a certain savoir faire; it requires an appreciation for, and an understanding of, the intricacies of shape and form. The occlusion of one patient is not the same as another patient’s occlusion. There is no “One Way” to treat all patients. We must adapt basic morphaesthetic occlusal principles to the specific clinical circumstances given, prudently judge signs and symptoms, carefully analyze masticatory movements, evaluate the entire patient complex—not just the craniomandibular function—and then proceed with treatment based on the sound anatomic, physiologic, and personal information gathered along with a clear pre-operative vision of theaesthetics and function which is to be achieved. Enlightenment is preceded by diligent, thorough research. Though knowledge may ultimately be limited–imagination  is limitless. Indeed imagination, visual imagery, and artistic creativity may even be more important than knowledge! Remember: Thought is the sculptor! Schopenhauer said, “Thoughts die the moment they are embodied by words”. True enough, but when creative thoughts are metamorphosed and embodied into structural form, as opposed to only words, an entirely

different result occurs. A work of art (or creating an occlusion!) is above all an adventure of the mind. After all, art and creativity pick up where nature ends.

You speak of Lord Byron and me; there is great difference between us. He describes what he sees. I describewhat I imagine. Mine is the harder task.

John Keats

The ordinary act of mastication ought not to become a self-destructive act which, in spite of our most valiant efforts, it oftentimes is. Pundits wryly opine, ‘success’often consists of going from failure to failure without the loss of enthusiasm.We can’t have good occlusion without good morphology, and poor morphology will only beget poor occlusion. (Fig. No. 7)

Fig. No. 7

Contemporary ‘wisdoms’ being the main historic landmarks of the past,we need creativity in order to break free from the suffocating stricturesthat have been set up by convention.We’ve all heard the old morphology adage “Form follows function”, yet in reality it’s simply mere dogma until we realize the higher truth that form and function are really one–inextricably interwoven, flawlessly fused, and beautifully bound. Structural beauty must always be a determining criterion in achieving successful function. Thus, every restoration we fashion should be the utopian re-integration of lost morphotypia via biomorphomimicry, dutifully paying its multiple tithes to the dignities of the periodontium, the morphology, the occlusion, the overall aesthetics, and most of all: THE PATIENT. It is difficult if not impossible, as I’ve mentioned, for most dentists to think otherwise than in the fashion of their own time. Yet almost always, the creative, dedicated, insightful minority have elevated the profession and made it better.

You are never too old to set another goal or to dream a new dream.

C.S.Lewis

In summary, allying the conjugate pairs of ART (right-brain imaging, shape & form,morphology) and SCIENCE (left-Brain research, facts, function) is incontrovertibly the key to gaining the combined skill and knowledge required to successfully treat problems arising in what is the common denominator in all dentistry, occlusion. Often considered by many to be dentistry’s bête noir, occlusion can be comprehensible and unambiguous, especially when not pursuing strictly dogmatic ‘scientific’ theories, and when artfully experienced on a creatively higher level. Having accomplished a “union of the disparates” ( Coleridge), occlusion actually transmutes to an veritable aesthetic to be embraced. As such, I have sought herein to provide an artistic alternative in teaching occlusion which seeks to remove–once and for all–the persistent “confusion in occlusion” by emphasizing the importance of understanding, internalizing, and employing the artful nuances of morphology as the ineluctable key to creating and maintaining a beautifully functioning occlusion. The things we do, define us. The things we create, make us. Purpose elevates what we do (Fig. 6). Simply put, the study of Occlusion is an adventure. To begin with, it is an unfamiliar dalliance with shape and form. Then it somehow becomes a mistress, then it becomes a master, then it becomes a possessive tyrant, then a terrifying monster. But just as you are about to be reconciled to your servitude, MORPHOLOGYrises up and slays the dreaded Occlusal Monster, setting you free to enjoy the fascinating adventure that is OCCLUSION. Thus is heralded the obligate rite of passage from artless neophyte to dental aesthete adroitly versed and disciplined in …

THE AESTHETICS OF OCCLUSION.

All the forces in the world are not so powerful as an idea whose time has come.  (Victor Hugo)

Miswak (Salvadora Persica Chewing Stick) And Its Role In Oral Health; An Update

 

Areej K Almas1                          BS

Khalid Almas2                          BDS, MSc, FDSRCS, FRACDS, MSc, DDPH.RCS,FICD

ABSTRACT: Miswak, as a cultural and scientific heritage oral hygiene tool, it is now being evaluated on evidencebased criteria.  Through comparing the naturally-occurring and scientific evolution of Salvadora persica’s usage, we will be able to better understand the uniqueness of miswak, relative to that of other oral hygiene tools as being a solo oral hygiene tool of a significant part of the World population. The review is an update on chemical composition, antimicrobial, anticariogenic, anti plaque, and antigingivtis effects of miswak on oral health in the context of invitro experiments and clinical trials. Special emphasize is on how to use and when to use miswak for effective cleaning of teeth and mouth. Recent scientific evidence regarding its probiotic role, cell viability and comparative cytotoxicity and research trends will be highlighted.

It is hoped that the review will help health care professionals to have better knowledge and awareness about miswak, to improve the quality of life of their culturally diverse patients population who are uninitiated for regular oral hygiene measures due to various constraints. The use of miswak on population bases is in line with the theme of primary health care approach (PHCA) and oral health promotion. Miswak has wider acceptance among many communities and populations around the world.

KEY WORDS: Miswak, Chewing stick, Salvadora persica, natural tooth brush, oral hygiene.

HOW TO CITE: Almas AK, Almas K. Miswak (Salvadora Persica Chewing Stick) And Its Role In Oral Health; An Update. J Pak Dent Assoc 2013; 22: 000-000.

INTRODUCTION

A healthy mouth leads to a healthy body. Good oral hygiene is the key to good oral and systemic health. Acceptable level of plaque control, from where periodontal disease cannot be initiated or progressed is the ultimate desire of oral and dental professionals. The body -mouth relationship is of great interest among health care professionals. With the increasing prevalence of oral and dental diseases, the international need for preventive and curative methods has been surfaced. Not only are alternate preventive and treatment methods being expanded but also safe, effective, economical and culture based traditional  remedies and products are being explored.  A tooth brush and tooth pastes are commonly used in developed and developing countries for cleaning teeth.

MISWAK IN A HISTORICAL PERSPECTIVE

The evolutionary development of the modern day toothbrush may be traced to chewing sticks that were used by the Babylonians. The use of chewing stick was recorded by the Babylonians in 5,000 BC and the fashion rapidly spread throughout the Greek and Roman empires. The chewing stick was also used by the Egyptians, the Jews, and among the Muslim world. References to the use of chewing stick can be found in the Talmud, as the Quesum,  the Siwak, Miswak and Arak. Its use as a chewing stick or Siwak was documented in the Arabian Muwasha written by Alwashah, in AD 900. It is believed that the modern day tooth brush was not known in Europe until about 300 years ago, Lewis and Lewis (1). Medical texts of ancient India, Susruta Samhita and Charaka Samhita,  have also emphasized on oral hygiene and brushing teeth with herbal sticks (2). Today miswak is being used in different parts of the world. Chewing sticks are known by  various names including the word  “miswak” or “arak” in Arabic, “qesam in Hebrew, “qisa” in Aramaic, “koyoji” in Japanese, “mastic” in Latin (3) and “mefaka” in Ethopia (4) and datun in Pakistan and India (5).

In many Middle Eastern, Asian, and African American communities, traditional methods of tooth cleaning are still used due to low cost, affordability, availability, usage in rituals, and to serve custom, and religious purposes (6). Chewing sticks have various other uses such as: using them as jaw exercisers, inducing a reflex of copious saliva secretion, combating undesirable oral habits including smoking and thumbsucking, and lastly, they can also be used during the teething process (7). In terms of geographical distribution, S. persica usage is widely spread and ranges from countries such as Malaysia, Nepal and India in the East through Iran, Iraq, Pakistan, Saudi Arabia, and Egypt to Mauritania in the West, from North Africa and Central Africa to Southwestern Africa (8).

In the Middle East, Arak (Salvadora persica) is the most common chewing stick. Additionally, the roots of African laburnum (C. siberianba) are  used in Sierra Leone and Neem (A. indica) is primarily common in the Indian subcontinent. Other forms of chewing sticks can be found in Western Africa, where the lime tree (C. aurantafolia) and the orange tree (C. sinensis) are utilized for oral health purposes. Not only are miswak used for oral hygiene, they are also related to religious rituals and social purposes (9).

One hundred and eighty-two kinds of plants/shrubs have been used as chewing sticks, throughout the developing world; the most significant is Arak, Salvadora persica (10). The roots, twigs, and stems are the specific parts of the plant that provide dental hygiene (11).

The miswak is a small, upright evergreen tree or shrub with white branches and aromatic roots, rarely ever more than three meters in height and 30 cm in diameter (12). The fresh leaves on the  S. persica can be utilized in traditional medicine for treating cough, asthma, scurvy, and other diseases, whereas, the flowers of the tree are used as a stimulant and are mildly purgative (9). Stems and roots of the S. persica are spongy, thus they can be easily chewed and crushed between the teeth. The chewing stick becomes quite spongy after it is soaked in water; therefore, it is highly unlikely to traumatize the gums, if used properly, while brushing (7). The stem or root is chewed on one end, until it becomes frayed and looks similar to the head of a toothbrush (9).

Considering the historical, cultural and religious importance of S. persica miswak as an oral hygiene and maintenance tool, this current review is an update on recent developments in miswak research. Major emphasize is on chemical composition, how to use and when to use miswak for effective cleaning of teeth and mouth. Recent scientific evidence regarding its probiotic role, cell viability and comparative cytotoxicity and research trends are  highlighted.

CHEMICAL COMPOSITION

The advantageous effects of miswak, in terms of oral hygiene maintenance and dental health, can be attributed to the mechanical role of brushing and its pharmacological component (9). Chemical analysis shows that miswak contains numerous, natural constituents that are known to benefit oral health. The chemical substances present in S. persica are as follows: chloride, fluoride, saponins, salvadorine, silica, sulfur, sterols,  trimethylamine, and vitamin C (7). Another chemical investigation demonstrates the following compounds present in the S. persica plant: b-sitostrol and m-anisic acid chlorides, salvadorea, and gypsum; organic compounds, including pyrrolidine, pyrrole, and piperidine derivatives; glycosides, such as salvadoside and salvadoraside; and flavonoids, including karmpferol, querceting rutin, and a quercertin glucoside (13). The main constituent of the Salvadora persica root oil is Benzyl- isothiocyanate (BITC) (14).   This component of the Salvadora persica root, Benzyl- isothiocyanate, exhibits broad-spectrum bactericidal activity (15) and inhibits the growth and acid production of Streptmutans (16). According to Chawla (17) , chewing sticks like Neem (A. indica), S. persica, A. arabica contain a noticeable amount of fluoride (79).

Many of Salvadora persica’s constituents cited above, aid in the prevention of decay and benefits to preserve the human dentition if utilized properly. The silica present in chewing sticks acts as an abrasive material to reduce stains and whiten teeth. Both the sulfur compounds and alkaloid (salvadorine) present in S. persica have a bactericidal role but, only salvadorine exerts a stimulatory action on the gingival

(9). The tannins and resins give protection against caries by forming a layer over the enamel due to the astringent effect on the mucous membrane. Chewing sticks obtained from plants similar to Aegles marmelosm, S. persica, A. indica, and Fagara zantholoxoids contain essential oils that exert analgesic, antiseptic, and carminative action. Strong anti-inflammatory action on the gums is provided by substance present in other plants, including Alnus glutinosa, Antidesma venosum, and A. indica (7). Lastly, due to the high concentrations of chloride present in S. persica miswak, calculus formation is inhibited (9). Also, since miswak is used regularly and for a longer period of time, severe calculus buildup does not occur.

THE PREPARATION OF A MISWAK

The recommended  method for preparing a usable chewing stick is discussed by Almas and Al-Lafi (5). A chewing stick is a piece of wood, usually from the stem of a plant that has an average length of fifteen centimeters and a diameter of one centimeter. Though chewing sticks are sold in several different lengths and diameters, it is important to adjust both the length and the diameter according to the general user. A length of twenty centimeters for adult use  and fifteen centimeters for children/minors are the size values recommended for convenience and to insure safe and proper use of the miswak. They also provided a brief anatomical description of the phloem, fibers, and wood of the S. persica plant. There is a large amount of phloem in the S. persica, as well as, widely spaced, think-walled fibers. The spongy wood can be easily crushed by the teeth and softened so that the miswak is chewable without any difficulty.

The first step is to prepare a chewing stick that is freshly cut so that they are supple and still possess all of their active constituents. The reason being, that a very dry chewing stick can damage the gums surrounding the teeth in the oral cavity.  It is vital to remember that if a stick is originally dry, it should be soaked in fresh water for twenty-four hours. If the stick is immersed in water for a longer period, it can cause the loss of active ingredients present in the chewing stick, and can even diminish the therapeutic properties the stick possesses. Next, in order to create bristle-like structures on the chewing stick, one side of it should be chewed on for few seconds, until the fibers stand out similar to individual bristles of a regular toothbrush (Fig 1.) After having been used for several instances, the chewing stick is either replaced by a new one or a

Fig 1. Bristles end of three different shaped chewing sticks.

fresh end is formed by cutting off the old bristles, and creating new ones by chewing and tapering it. It is recommended that the chewing stick should be kept at a moist place when not in use. It should be washed/rinsed with water before using it again (7).

TECHNIQUES OF USING A MISWAK

Almas and Al-Lafi (7), gave an account of the mechanical techniques employed for removing plaque using a toothbrush and a miswak are analogous. Vertical and horizontal brushing is important, however, the manual dexterity of individuals, their attitude towards and knowledge of oral health is the critical basis needed to maintain proper oral cleanliness. The chewing stick resembles to the toothbrush as both have bristles and are utilized to remove biofilm/plaque from the tooth surfaces mechanically. However, the chewing stick also have a chemical role and may be chewed or sucked for many hours daily by some people.

A length of 15 cm for children and 20 cm for adults is highly recommended for convenient grip and ease of manipulation.  A diameter of 1 cm makes for suppleness and sufficient firmness (7).

Two basic holds have been described in order to have a firm,  well controlled movement of the brushend of the chewing stick in  mouth is achieved and that every part of oral cavity is reached with relative convenience. They are described below (8); 4    Five fingers grip (shown in figure 2) q The four fingers of one hand are curled lightly found the stick, with the index finger nearest the end to be chewed.

Fig 2.  Five fingers grasp (palm grasp) of chewing stick.

q The pulp of the thumb rests firmly on the opposite side of the stick to the index finger, the thumb is thus in a higher position than the index finger. The thumb controls the movement of the stick and retains it in a firm grip. All tooth surfaces are accessible if the wrist or arm is moved as needed.

4    Three fingers grip (shown in figures 3 & 4) q The chewing stick is placed between the index and third fingers. The operative end of the stick is pointed upwards when the hand is in the supine position. q The fourth and fifth fingers are kept clenched on the palm. q The thumb rests on the side opposite the index the third fingers, where it assumes the dominant role and

Fig 3.  Three fingers grasp of chewing stick. position.

The tooth cleaning movement should be directed away from the gingival margin of the teeth on both the buccal/facial and lingual surfaces. An anterior to posterior scrubbing movement is carried out on the occlusal surfaces. Careful movement and effort should be done to avoid damaging the soft tissues of the oral

Fig 4.  Three fingers grasp of chewing stick (being used by a child). cavity (Fig 5). Satisfactory cleaning can be achieved if

Fig 5. The application of chewing stick on buccal surfaces (A), on lingual surfaces (B) and on occlusal surfaces (C). the procedure is practiced for three-five minutes.

Tongue is another part of the oral cavity that needs to be cleaned to maintain proper oral hygiene. The tongue is considered to be the cause of bad breath/halitosis if there is a buildup of a white coating on the dorsum of the tongue. Likewise to cleaning teeth with it, the miswak is very effective against cleaning the surface of the tongue in two ways. The bristle end of the miswak can be used, however, for best possible outcome, the sticks can be broken into a V-shaped manner and the resulting blade can be used to scrape several times across the tongue, posterio-anteriorly. The miswak is not only a natural toothbrush; it can also become a makeshift natural tongue scraper for achieving good oral hygiene (7).

WHEN TO USE THE MISWAK

Unlike the toothbrush, that is usually allotted a specific time-morning, afternoon, or night, to be usedmiswak can be used at various different times throughout the day. For instance, many people use miswak in public places, while conversing, before breakfast, before going to bed, before praying, and so on (7). Ideally, the chewing stick should be used before meals or immediately after meals so that the bacteria that convert sugar into acid can be removed. However, it was found that the use of miswak after meals is not practical, since the drop in pH and the associated damage takes place within a few minutes, and after twenty minutes, the saliva executes the buffering role. In general, the use of miswak, five times a day, is recommended for all benefits of the naturally occurring effects to take place.  To the Muslim, the use of chewing stick is an important part of ablutions before worship which takes place five times daily. The regular use of chewing stick conforms with the theme of primary health care and has long been established practice with certain cultural and religious beliefs and norms (7).

EFFECTS OF MISWAK ON ORAL HEALTH

Antimicrobial effects

Some invitro studies exemplified that S. persica extracts inhibited the growth of various oral aerobic and anaerobic bacteria (6). In an invitro study by Almas (15), the antimicrobial effects of the aqueous extract belonging to seven different types of chewing sticks were compared. The several varying types of chewing stick that were examined included Azadirechta indica, Olea europaea, Acacia Arabica, S. Persica (common name: Peelu and Arak), Gycosmic pentaphylla, and Capparis aphylla. The four microorganisms that were tested consisted of Strept  faecalis, Strept mutans, Staph aureus, and C albicans.  The aim of the experiment was to find out which microbe was affected by one or more of the chewing sticks and if so, by how much (in mm) was their growth inhibited. It was concluded that there was no effect of any chewing stick on Stept mutans, Staph aureus, and C albicans microorganisms. However, the results also concluded that S. persica (Arak) and Acacia Arabica had significant antimicrobial activity against Strept faecalis at 50% concentration of the miswak extract. The inhibition zone was up to two millimeters for the two chewing sticks.

Another invitro experimental study performed by Almas et al. (19), focused on comparing miswak extract with commercially available mouth rinses. Similarly, there was an experiment to check if there was any antimicrobial activity. Once again, the microbes included were; Strept faecalis, Strept pyogenis, Strept mutans, C albicans, Staph aureus, and Staph epidermis. Mean growth inhibition of the various microbes was recorded (in mm). It was demonstrated that a 50% extract of S. persica miswak was effective against both Strep. mutans and Staph. faecalis.

The experiment resulted that there was a seven mm inhibition zone for Strep. faecalis and a three millimeter inhibition zone for Strep. mutans. However, there was no microbial inhibition for the remaining microorganisms.

From the two studies, Almas (18)  and Almas et al. (19), it can be concluded that utilizing miswak does in fact, have antimicrobial effects against two types of microorganisms. There is stronger action presented against Streptococcus faecalis as compared to Streptococcus mutans. In the examination of the antimicrobial activity of chewing extracts against different human pathogens, much effort has been expended (6). Though not all dental hygiene tools are helpful in thoroughly inhibiting all pathogens, the reduction of harmful microbial organisms that exist in the oral cavity is still a significant achievement.

Various studies have shown that S. persica  contains substances that possess plaque inhibition and antibacterial properties against several types of cariogenic bacteria which are commonly found in the oral cavity. The growth and acid production properties of these bacteria are thus inhibited (20, 21, 22, 23).

AL-Lafi and Ababneh (24) evaluated the antibacterial properties of S. persica against a few oral aerobic and anaerobic bacteria and reported that the extract of these sticks had a drastic effect on the growth of Staph aureus, and a variable effect on other bacterial species. They informed that the chewing sticks used were harvested one month earlier, and suggested that using more fresh sticks will give better and improved results. Almas et al. (23) compared fresh vs. one- monthold miswak extracts for antibacterial activity and found no difference. A comparison of alcohol and aqueous extract of miswak was also evaluated. It was reported that miswak alcoholic extract is more effective than aqueous extract for antibacterial activity (25). A recent study by Almas et al. (26) reported that, the S. persica extract, at a 50% concentration, delayed the growth of Actinomyces naeslundii, Lactobacillus casei, Staph aureus, Strept gordonii, Strept mutans, Strept oralis, Strept sanguinis, Veillonella sp. PK1910, F nucleatum and C albicans compared to controls where the extract was replaced by dPBS. 25% extract had a bacteriostatic effect in subset of these species, while 10% extract had no effect. On the contrary, the S. persica extract did not affect the planktonic growth of Lactobacillus fermentum. Killing assays showed that the extract had a partial bactericidal effect on most of the strains tested. The S. persica extract did not affect the viability of C. albicans, S. aureus and L. fermentum. Sofrata et al., (27), reported that the inhibitory effect was most obvious on P. gingivalis, A. actinomycetemcomitans, and H. influenza, comparatively less on S. mutans, and least on L.acidophilus. Suspended miswak pieces had comparable or even stronger effects than the miswak embedded in agar medium.

ANTIFUNGAL ACTIVITY

Al- Bagieh et al. (28) concluded that aqueous extracts of miswak could be used to reduce growth of C. albicans. Such inhibition lasts for up to 36 hours at concentrations of 15% and higher. A recent study by Almas et al. (26) reported that Salvadora persica extract did not affect the viability of C.albicans.

Al-Bayati and Sulaiman (29) compared the aqueous and methanol extracts of S. persica chewing stick for antimicrobial activities against seven isolated oral pathogens (S. aureus, Strept mutans, Strept pyogenes, E. faecalis, L acidophilus, P aeruginosa, and C albicans) using two different methods. Both antimicrobial assays resulted that the aqueous extract inhibited all isolate microorganisms and was more efficient than the methanol extract, which was resisted by L. acidophilus and P. aeruginosa. The most pronounced and strongest antibacterial activity was shown by the aqueous extract against E. faecalis. Turbidity tests exhibited that both extracts had equal antifungal activity against C. albicans. Further research is needed in antimycotic/antifungal effects of miswak.

PROBIOTIC AND PREVENTIVE ROLE OF S. PERSICA MISWAK

Mehanna and Reid (30), studied the effect of miswak extract on oral pathogens and its potential for probiotic use concluded that, miswak had a marked inhibitory effect on the streptococci bacteria and addition of Lactobacillus strains significantly reduced the viable counts of S. mutans. Almas et al. (26)  reported that S. 

persica extract had moderate bactericidal properties against a wide range of oral microorganisms.

Interestingly, it did not affect in any way Lactobacillus fermentum, a commonly used probiotic bacterium. The finding has not been observed in any previous studies. The quest in the probiotic role of miswak is in progress and hopefully soon further developments would be part of scientific literature.

ANTIOXIDANT CAPACITY OF MISWAK

There is growing interest in bioactive compounds of S. persica miswak especially antioxidant compounds (31). By definition, antioxidants are substances that when present in foods or body at low concentrations compared with that of an oxidizable substrate markedly delay or prevent the oxidation of that substrate. Various antioxidants included enzymatic antioxidants (e.g., superoxide dismutase, peroxidase, polyphenoloxidase and catalase) and nonenzymatic antioxidants (e.g., ascorbic acid (vitamin C), a-tocopherol (vitamin E), glutathione, carotenoids, and flavonoids) (32). Antioxidants have been considered to help the body to protect itself against various types of oxidative damage caused by reactive oxygen species, which  are linked to a variety of diseases including cardiovascular diseases, cancers (33) neurodegenerative diseases, Alzheimer’s disease (34) and inflammatory diseases (35) and some other ailments. The supplement of the diet (or other uses) with antioxidant compounds is one of solutions of this problem that are preserved in natural plant sources (36). These natural plant antioxidants sources can therefore serve their role as a type of preventive medicine. Some investigators suggested  that two thirds of the world’s plant species have medicinal value; in particular its considered that many medicinal plants have great antioxidant potential (32).

Mohamed and Khan (31) reported that furan derivatives containing hydroxyl groups could possess antioxidant activities. The antioxidant enzymes were also detected in the chewing stick  extract with high level of peroxidase and low level of catalase and polyphenoloxidase. The synergistic actions of antioxidant compounds and antioxidant enzymes make chewing stick as a good tool for cleaning teeth, oral hygiene, oral health  and food purposes.

ANTIPLAQUE, GINGIVAL AND PERIODONTAL HEALTH EFFECTS OF MISWAK

It has been observed, both clinically and experimentally, that S. persica chewing stick was as effective and useful as a toothbrush for reducing plaque on buccal tooth surfaces (37). While assessing plaque removal in children from Ethiopia, it was confirmed that the chewing stick appeared to be as effective as the toothbrush, if not more (4).  In addition,  practicing   the proper use of chewing stick as an oral hygiene aid, significantly lower plaque scores in comparison with the use of commonly used toothbrushes (38).

A recent statement on oral hygiene measures  (39) concluded that bacterial plaque plays an important role in the etiology of dental caries, gingivitis and periodontitis and effective removal of dental plaque can result in the prevention and or reduction of the above mentioned diseases and conditions (6). As a consequence of plaque reduction, the usage of chewing sticks can also assist in the reduction of gingival inflammation. However, chewing sticks can cause occlusal tooth wear and a small degree of gingival inflammation if used improperly or excessively. Moreover, if a miswak stick is chewed upon in the same area of the mouth, and over a long period of time, it can end up proving to be detrimental instead of beneficial (7). Gingival indices were found significantly lower following the use of S. persica chewing sticks in comparison with the use of a commonly used conventional toothbrush without toothpaste (38).

Relatively low number of tooth loss in adults have been reported in countries where miswak is commonly used (10). Epidemiological studies (40,41) emphasized  that chewing stick use had beneficial effects on the prevalence and prevention of periodontal diseases and caries. Some other studies reported low periodontal treatment needs among Saudi adults who were regular  miswak users (40, 42). An epidemiological study of nomadic population of the Kaisut Desert region of Kenya reported that dental caries and advanced periodontal disease were rare among miswak users under the age of  

50 years (43). A retrospective study from Saudi Arabia reported conflicting results about miswak users. They observed deeper periodontal pockets and a higher prevalence of periodontal diseases among miswak users (44) than did non-users. In an institutional study from Sudan (45), showed that the periodontal status of regular miswak users was similar to or slightly better than that of toothbrush users. The above mentioned studies reflect the beneficial use of miswak for the gingival and periodontal health.

CYTOTOXICITY OF MISWAK EXTRACT

The effective role of an ideal antimicrobial agent depends on its ability to kill microbes while causing minimal toxicity to host cells (minimal collateral damage). Rajabalian et al. (46) compared pesica mouthwash and Chlorhexidine mouthwashes on cultured human and  mouse cell lines. The cytotoxic effects of four dilutions of Persica and Chlorhexidine mouthwashes on KB, Soas-2, J744 A1, and gingival fibroblast cells were evaluated using  MTT assay. The effect of fetal calf serum (FCS) components on the cytotoxicity of these mouthwashes was also evaluated. They found that both Persica and Chlorhexidine mouthwashes were toxic to epithelial, fibroblast, macrophages, and osteoblast cells in concentration-dependent manner.

A recent comparative study by Almas et al.(47), on cytotoxicity of S. persica aqueous extract and Chlorhixidine  gluconate on L929 mouse fibroblasts obtained from American Type Culture Collection (Manassas, VA, USA). They  concluded that the cell viability of miswak extract was 88%, 90%, 97%, 95% in original strength (50%) and 1/2 , 1/4, 1/8, 1/16, 1/32 dilutions, while the cell viability of CHX is 3% , 47%, 87%, 93%, 92% and 95% in the corresponding concentrations. Miswak extract had significantly less cytotoxicity than CHX in the original and 1/2, 1/4 dilutions (p=0.05).

Mohammad and Turner (48) tested the cytotoxic potential of the S. persica miswak and its diffusible components on oral tissues using the tissue culture agar overlay method. They reported no cytotoxic effect of freshly cut S. persica chewing stick, but observed that the same plants contained harmful components if used after 24 hours. A recent study evaluated the role of direct administration of high doses of S. persica miswak extract to mice,  reported minor side effects on male and female reproductive systems and fertility (49). An earlier study concluded that neither aqueous nor ethanolic S. persica miswak extract was toxic to mice, reported minor side effects on male and female reproductive systems and fertility (49). An earlier study concluded that neither aqueous nor ethanolic S. persica miswak extract was toxic to mice at doses of up to 1200 mg/kg (50).

Further research is needed to assess the comparative cytotoxic effects of miswak extract and Chlorhexidine to human macrophages, epithelial cells, fibroblasts and osteoblasts. That would help to precisely use of miswak extract or chlorhexidine after periodontal or oral surgery procedures.

MISWAK AS A CULTURAL HERITAGE AND ORAL HEALTH PROMOTION TOOL

 In the early Islamic period, the use of miswak became a part of a cultivated and elegant mode of life and as a prominent feature of Islamic hygienic jurisprudence. Today, cross-cultural knowledge can help motivate public health dentists and dental hygienists to recognize culturally accepted behaviors for the purpose of strengthening patient-provider relationships and optimizing public health outcomes. Such recommendations can offer ways to mix or merge western healthcare with Islamic practices and precepts surrounding the use of miswak and dental hygiene practices considering that healthcare providers and professionals live and work in a global village or society. (51). The French philosopher Auguste Comte (1798-1857) stated, “demography is destiny”. With world populations becoming more culturally diverse, healthcare providers must practice cultural awareness and sensitivities to achieve trust, and to direct the patient-provider relationship toward the desired goal of quality oral health care for all populations. Unfortunately, ignorance of customs can undermine the establishment of trusting relationship. As in the case of the miswak chewing stick; oral health care professionals should 

review miswak use with their patients to ensure proper and effective use and angulation to achieve maximum bacterial plaque removal. (51-53). Miswak being a cultural and scientific heritage has a lot more to offer to present day oral hygiene needs of many communities around the world.

CONCLUSION AND RECOMMENDATIONS

Miswak has been proven effective as an oral hygiene

aid and should be introduced and promoted to general population based on scientific rationale.  In addition, the use of the miswak conforms to the theme of primary healthcare approach, as well as certain cultural, traditional, social, and religious beliefs and rituals. Incorporating the utilization of miswak into the healthcare system of many developing countries will greatly facilitate the masses with financial constraints, as well as limited oral health care facilities.

Miswak is  available in rural areas of developing countries, it does not require special technology to produce. Health care resources are limited in many countries, and there is a growing concern to scientifically research, and test freely available and relativel low cost traditional preventive tools in order to improve the healthcare conditions of the world population.

Despite the high initial cost of further investigating the properties of S. persica miswak, it will prove to be economically and financially profitable once the consorted efforts are made. The advantageous effects of miswak usage are undeniable, and it is indisputable that there is a plethora of benefits of utilizing the miswak. Now, the responsibility of healthcare professionals including, medical and dental doctors, hygienists across the globe is to revisit miswak for better oral and systemic health of their respective populations. Certainly that would improve the quality of life of those populations and societies and reduce the oral diseases and financial burden. Countries like Pakistan, could benefit from  the culture and religionbased oral hygiene use of miswak both at rural and urban levels. Healthcare professionals should learn more about the recent advances in scientifically proven role of miswak for their respective clientele.

Further research should be conducted to explore probiotic and antioxidant role of miswak. Double blinded, randomized clinical trials (RCTs) comparing clinical parameters of periodontal health and diseases would add into evidence-based scientific credibility and practices of miswak.

ACKNOWLEDGMENTS

Authors would like to thank and appreciate the dedicated researchers for their continuous  interest in miswak research. I am (KA) pleased to share my twenty years of scientific progress and contributions to miswak (Salvadora persica chewings sticks) literature (Appendix;  A). It is hoped the review would attract and invite new researchers in the scientific journey of miswak.

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  8. Khoory The use of chewing sticks in preventative oral hygiene. Clin Prev Dent 1983. 5: 11-14.
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  14. Bader A, Flamini G, Luigi P, and Morelli I. The composition of the root oil of Salvadora persica L. J Essential Oil Re 2002; 14: 128-129.
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  18. Almas K. The antimicrobial effects of seven different types of Asian chewing sticks. Odontostomatol Trop 2001; 24:17-20.
  19. Almas K, Skaug N, and Ahmad I. An in vitro antimicrobial comparison of miswak extract with commercially available non-alcohol mouth rinses. Int J Dent Hygiene. 2005; 3: 18-24.
  20. Lewis WH and Elvin-Lewis MPF. Oral Hygiene,Medical Botany. John Wiley &  Sons, New York, 1977:pp 226-270.
  21. Abo AL-Samh D and AL-Bagieh N. A study ofantibacterial activity of the miswak extract in vitro. Biomedical Letters 1996; 53: 225-238.
  22. Brown JM and Jacobs JW. An investigation into antibacterial activity in chewing sticks against oral streptococci. Odontostomatol Trop 1979; 2 :25-30.
  23. Almas K, AL-Bagieh N, Akpata E. In vitro antimicrobial effects of freshly cut and 1-month old miswak (chewing stick). Biomed Lett.1997;56: 145149.
  24. AL-Lafi T and Ababneh H. The effect of the extract of the miswak (chewing sticks) used in Jordan and the Middle East on oral bacteria. Int Dent J 1995; 45: 218-222.
  25. AL-Bagieh N and Almas K. In vitro antibacterial effects of aqueous and alcohol extracts of miswak (chewing sticks). Cairo Dent J 1997; 13: 221-224.
  26. Amas K, Diaz P I, Eshky R T, Khan Z A AND Dongari-Bagtzoglou A. Invitro antimicrobial effects of Miswak (Salvadora persica) on oral microorganisms. IADR 2010; Abstract # 2671.
  27. Sofrata AH, Claesson RLF, Lingstrom PK, Gustafsson AK. Strong antibacterial effects of miswak against oral microorganisms associated with periodontitis and caries. J Periodontol 2008;79: 1474-1479.
  28. AL-Bagieh NH, Idowu A and Salako O. Effect of aqueous extract of Miswak on the in vitro growth of Candida albicans. Microbios 1994; 80:107-113
  29. Al-Bayati, F., Sulaiman, K., 2008. In vitro antimicrobial activity of Salvadora persica L. extracts against some isolated oral pathogens in Iraq. Turk. J. Biol. 32, 57-62.
  30. Mehanna N and Reid G. Effects of meswak (Middle Eastern Tree Bark) on oral pathogens and potential for probiotic applications. J Med Food 2010;13: 729-732.
  31. Mohammed S A and Khan J A. Antioxidant capacity of chewing stick miswak Salvadora persica. BMC Complement Alternative Med 2013; 13:40.
  32. Krishnaiah D, Sarbatly R, Nithyanandam  A review of the antioxidant potential of medicinal plant species.  Food Bioprod Process 2011; 89:217-233.
  33. Gerber M, Boutron-Ruault M C, Hercberg S, Riboli E, Scalbert A , Siess MH. Food and cancer: state of the art about the protective effect of fruits and vegetables. Bull Cancer 2002; 89:293-312.
  34. Di Matteo V, Esposito E. Biochemical and therapeutic effects of antioxidants in the treatment of Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis. Curr Drug Targets CNS Neurol Disord 2003; 2:95-107.
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  37. Mohammed B, Jan B, Sarah B, Meshari F, and Otaibi AL. The effectiveness of chewing stick miswak on plaque removal.  Saudi Dent J 2006; 18: 125-33.
  38. Gazi M, Saini T, Ashri N, Lambourne A. Meswak chewing stick versus conventional toothbrush as an oral hygiene aid. Clin Prev Dent 1990; 12 (4): 19-23
  39. Consensus  Statement  on Oral Hygiene. Int  Dent J 2000; 52: 235-242.
  40. Al-Khateeb T, O’ Mullane D, Whelton H, Sulaiman M. Periodontal treatment needs among Saudi Arabian adults and their relationship to the use of the Miswak. Community Dent Health. 1991; 8: 323-328.
  41. Younes S, EL-Angbawi M. Dental caries prevalence in intermediate Saudi schoolchildren in Riyadh. Community Dent Oral Epidemiol 1982; 10: 74-76.
  42. Guile E. Periodontal status of adults in central Saudi Arabia. Community Dent Oral Epidemiol. 1992;20: 159-160.
  43. Carl W, Zambon J. Dental health of the Rendille and Samburu of the northern   frontier district of Kenya. N Y State Dent J 1993; 59: 35-39.
  44. Eid M, Selim H, AL-Shammery A. The relationshipbetween chewing sticks (Miswak) and periodontal health.3. Relationship to gingival recession. Quintessence Int 1991; 22: 61-64.
  45. Darout I, Albandar J, Skaug N. Periodontal status of adult Sudanese habitual users of miswak chewing sticks or toothbrushes. Acta Odontol Scand 2000 a; 58 (1): 25-30.
  46. Rajabalian S, Mohammadi M, Mozaffari B. Cytotoxicity evaluation of Persica mouthwash on cultured human and mouse cell lines in the presence and absence of fetal calf serum. Indian J of Dent Res 2009; 20 (2): 169-173.
  47. Almas K, Zhu Q , Komabayashi T. Cytotoxicityof persica (miswak) Extract and Chlorhexidine Gluconate on Fibroblasts. IADR 2012 ; Abstract # 1244.
  48. Mohammad A , Turner J. In vitro evaluation of Saudi Arabian toothbrush tree (Salvadora persica). Odontostomatol Trop 1983; 6: 145-148.
  49. Darmani H, AL-Hiyasat  A, Elbetieha A, Alkofahi A. The effect of an extract of Salvadora persica (Meswak, chewing stick) on fertility of male and female mice. Phytomedicine 2003;10: 63-65.
  50. Ezmirly S, Cheng J, Wilson S. Saudi Arabian medicinal plants: Salvadora persica. Planta Med 1979; 35: 191-192.
  51. Aboul-Enein B H. The miswak (Salvadora persica L.) chewing stick: Cultural implications in oral health promotion. King Saud Uni J Dent Sci (2013) in press.
  52. Sirois M, Darby M, Tolle S. Understanding Muslim patients: cross-cultural dental hygiene care. Int J Dent Hyg 2013;11:105-114

Garcia R I, Cadoret C, Henshaw M. Multicultural issues in oral health. Dent Clin North Am 2008;52: 319-332.


  1. University of Connecticut, College  of  Liberal Arts and Sciences, Storrs Campus.Connecticut. USA
  2. Professor of Periodontology Director Predoctoral Periodontics &Director International Fellowship in Advanced Periodontics Division of Periodontology,
  3. University of Connecticut, School of Dental Medicine Farmington. Connecticut. CT 06030. USA

Email: Almas@uchc.edu,  khalidalmas9@gmail.com

Keratinization Of Sulcular Epithelium In Low Frequency Noise Exposed Mice

 

Toqeer Ahmed Iqbal1                     MPhil, MBBS

Brig Shadab Ahmed Butt2            MBBS, MPhil, PhD

Lt Col Shabnam Hamid3               MBBS,FCPS

OBJECTIVE: The study was conducted to evaluate the histomorphological effects of low frequency noise on the periodontium of mice.

METHODOLOGY: Thirty BALBc mice, both male and female, were selected and divided into three equal groups having equal number of male and female animals. Control group A was exposed to normal environment of animal house, experimental group B was kept in silent condition and experimental group C was exposed to low frequency noise of 200 Hz for three months. The results of the experimental groups were compared with the control, and with each other. Statistical analysis was done using chisquare test at a confidence level of 95 percent and p value of <0.05 was considered as statistically significant. Results: Presence of keratinization of sulcular epithelium was statistically significant when group A was compared with group B and group B was compared with group C. Although there was no statistically significant difference in mean thickness of sulcular epithelium among the three groups but it was comparatively less in group C.

CONCLUSION: It was concluded that low frequency noise significantly increases the keratinization of sulcular epithelium.

KEY WORDS: Low frequency noise, keratinization, periodontium, Sulcular epithelium

HOW TO CITE: Iqbal TA, Butt SA, Hamid S. Keratinization of Sulcular Epithelium in low Frequency Noise Exposed Mice. J Pak Dent Assoc 2013; 22: 229-233.

INTRODUCTION

Our environment is full of different types of pollution of which noise pollution is an important component.

It is most prevalent and almost beyond the individuals control. This problem is not new. It has been present since ancient Roman and German eras and special laws were formulated at that time according to prevalent circumstances. The use of iron wheeled wagons and horse riding was prohibited to avoid effects of noise on general public. But the time has changed and magnitude and intensity of sound has increased significantly through the ages1.

In the present day environment, the noise has become a major concern for urban community of most of the developing countries. It is being further increased due to increasing industrialization and development of large infrastructure and heavy duty mobile sources of transportation. In the present era of power shortage, use of generators has increased this problem even more.

On physical terms, like source, propagation and perception, there is no difference between sound and noise. Noise is defined as unwanted or undesired sound. The frequency and intensity are also different. Frequency is defined as number of vibrations in one second and denoted as hertz while intensity is the loudness of sound and expressed as decibel. The audible frequency of sound ranges from 20 to 20000 Hz. Infrasound is the frequency below 20 Hz and ultrasound is above 20000 Hz. The term low frequency noise (LFN) is attributed to frequency of > 500 Hz, although some authors claim it to be between 20 to 250 Hz [1]. Low frequency noise is an essential part of frequencies generated in daily life by automobiles, heavy machinery, fans, generators and aircrafts[2].

Periodontium is a group of structures responsible for holding the tooth in the mandible or maxilla. These include cementum, periodontal ligament, alveolar bone and gingiva. The gingiva is anatomically divided into the unattached (marginal), attached and interdental gingiva.

The marginal gingiva forms the coronal border of the gingiva which surrounds the tooth, but is not adherent to it. Gingiva is composed of epithelium and connective tissue. Epithelial component comprises of gingival epithelium, sulcular epithelium and junctional epithelium. The gingival epithelium is stratified squamous keratinized epithelium that lines the gingiva. The basal cell layers of all 3 types of gingival epithelia are composed of rapidly proliferating cells that migrate toward the outer surface of the tissue.The keratinocyte is the main cell type of the gingival epithelium. Other cells found in the epithelium include Langerhans cells, Merkel cells, and melanocytes. The keratinization process includes flattening of the cuboidal cells, production of keratohyaline granules, and disappearance of the nucleus4. The gingival sulcus is lined with a non-keratinized stratified squamous epithelium that is referred to as sulcular epithelium. The gingival sulcus is bound by the junctional epithelium apically and the tooth and the sulcular epithelium on the sides. Sulcular epithelium lacks rete pegs. It is suggested that the non-keratinized nature of the sulcular epithelium is the result of the local irritation and inflammation within the gingival sulcus. Gingival connective tissue consists of collagen fibres (type I and III), fibroblasts, nerves, blood vessels, lymphatics, macrophages, eosinophils, neutrophils, T and B lymphocytes, and plasma cells 5,6. This connective tissue is called lamina propria with a superficial papillary layer and deeper reticular layer. Gingival sulcular fluid is secreted by the sulcular epithelium. It contains numerous defense cells, electrolytes and antibodies providing protective effect7.

The effects of LFN on histomorphology, physiology and biochemical parameters have been studied on different organs and systems of body. Vibroacoustic disease (VAD) is defined as pathology involving whole body in response to chronic exposure to LFN. It is characterized by proliferation of extra cellular matrix without inflammation8. The cause of injury can be direct vibrational effect, stress, vascular involvement or combination of these factors 2.

Chronic exposure to LFN affects different body systems including endocrine system, cardiovascular system, immune system, reproductive system, vestibular system, respiratory system, central nervous system, digestive system and oral cavity. Periodontium can be affected by stress9, smoking10, drugs11, alcohol12 and low frequency noise2.

The objective of this study was to see the effects of the low frequency noise on the histomorphology of the sulcular epithelium in mice. It was carried out in the Department of Anatomy, Army Medical College Rawalpindi, in collaboration with National Institute of Health (NIH), Islamabad. The experiment was carried out with the permission of ethical committee of Center for Research in Experimental and Applied Medicine (CREAM), of the Army Medical College, Rawalpindi. The study was laboratory based randomized control trial and of one year duration.

METHODOLOGY

Thirty adult BALB/c mice, half male and half female, with initial body weight of 25-28 grams were used in the experiment and were kept in controlled environment of Animal house of National Institute of Health, Islamabad. They were fed with standard NIH laboratory diet for three months. The mean final body weight was 42.00±1.224gm. Mice were randomly divided into three groups (n = 10 animals, half male and half female, in each group). The mice in group A (Control) were kept in normal environment of animal house for three months. The mice in group B (Experimental) were kept in silent conditions for three months and mice of group C (Experimental) were exposed to low frequency noise of 200 Hz continuously for three months.

Exposure to Low Frequency Noise

Low frequency noise (LFN) of 200 Hz was produced by analogue frequency generator purchased from local market. Power supply was with DC adopter with stand by battery of nine volts for uninterrupted power supply. The frequency output was confirmed with the help of digital universal frequency counter (Thurlby Thunder, model No TF 830, 1.3 GHz) and oscilloscope (Hitachi VC 6155) .The intensity of sound was measured with sound level meter (RadioShack analogue model 33-4050). Frequency and intensity of sound were recorded at start, middle and end of the experiment. It was placed outside the cages.

Sacrifice and Dissection

At the end of 90 days, the animals were euthanized by placing ether soaked cotton in the jar 13. The skin was removed by scalpel. Mandible was dislocated from the temporomandibular joint and dissected out. Tongue and surrounding muscles were removed. Care was taken to protect the buccal and lingual mucosa from any injury during the procedure (Fig 1).

Fig 1: Photograph showing dissected mandible

Tissue Processing

Hemisected mandibles were fixed with 10% formalin and embedded in liquid paraffin. The blocks were allowed to solidify on cold plate14. 5µm thick sagittal slices of animal tissue were made using rotary microtome (Leica rm 255) 15.The observations on each of the parameters were recorded. The lining epithelium was assessed for any apparent keratinization. One slide per specimen was observed under high power objective and keratinization was recorded as present or absent.

Statistical Analysis

The data was entered for analysis in the computer software SPSS version 18. Mean and standard deviation were calculated for quantitative data using ANOVA statistical test. Chi-square tests was applied for qualitative data to measure the level of significance for analysis at a confidence level of 95 percent and p value of <0.05 was considered as statistically significant.

RESULTS

The histological sections of periodontium showed all the components under H&E stain. In control group A, sulcular

Fig 2: Comparison of keratinization of sulcular epithelium among

Fig 3: Photomicrograph of animal from group A showing keratinized SE (K). D: Dentin, CT: Connective tissue. H&E 40X.

Fig 4: Photomicrograph of animal from group B showing non keratinized sulcular epithelium (SE). CT: Connective tissue, MEp: Marginal epithelium. H&E 40X epithelium was found to be of stratified squamous variety with flattened nuclei. Outer most layers of seven out of ten specimens (3 females and 4 males) showed keratinization (Fig 2). Two of the female specimen showed parakeratinization also (Fig 3). The specimens of experimental group B showed sulcular epithelium to be composed of stratified squamous epithelium. The basal

Fig 5: Photomicrograph of animal from group C showing keratinized sulcular epithelium (SE). H&E 40X

cells were cuboidal shaped and the top most layer having flattened nuclei (Fig 3). Only two out of ten specimens (20%), one male and one female, showed keratinization of sulcular epithelium (Fig 2). In experimental group C, the sulcular epithelium was composed of stratified squamous epithelium with keratinization. Keratinization of sulcular epithelium was seen in nine out of ten specimens. Of these five were female and four were male animals (Fig 5). Same findings were observed in group A but these were not so in group B which was exposed to silent environment.

DISCUSSION

Environmental noise pollution, a form of air pollution, is a continuous threat to normal health and well-being.  It is becoming

 

*p value <0.05 significat Statistical test applied is ANOVA

increasingly severe and widespread than ever before, and it will continue to increase in magnitude and severity because of change in life style, increase in population, urbanization, and the associated growth in the use of increasingly powerful and highly mobile sources of noise.  It is likely to continue due to sustained growth in highway, rail, and air traffic, which are the important sources of environmental noise.

 

In the normal tissues, sulcular epithelium is non-keratinized. In the current study, sulcular epithelium was found to be keratinized in 70% of animals in group A, 20% of animals in group B and 90% of animals in group C (Fig 2). ANOVA was approved as statistical test. Keratinization was statistically significant when group A was compared with group B (pvalue0.02) and highly significant when group B was compared with group C (p value0.001). The degree of keratinization was almost same when group A was compared with group C and it was not statistically significant (p value > 0.05) (Table 1). No

TABLE 1

Comparison of p-value among groups A, B and C

 

Chi-square test applied

*p value <0.05 significat

significant difference was found among the two genders. These findings are in agreement with findings observed by Cafesse et al 16 in two separate studies when they observed significant keratinization of sulcular epithelium in response to intensive antimicrobial therapy. In another study by same researchers in 1982, it was proposed that mechanical stimulation of sulcular epithelium plays a role in promoting its keratinization17. In our study, this mechanical stimulation may be elicited due to vibrational effect of low frequency noise. Changes in keratinization are also menisfested in response to diabetes, antimicrobial therapy and smoking 18.

In another study done by Vogel in 1981, keratinization was induced in a group of subjects by

intrasulcular tooth brushing. Biopsies revealed no effect of keratinization on permeability of sulcular epithelium 19. It has been suggested that in normal conditions, keratinization of sulcular epithelium is prevented by contact of epithelium to the tooth 20.

One of the major functions of sulcular epithelium is the secretion of gingival sulcular fluid. This fluid contains many protective agents. When sulcular epithelium is damaged due to any cause, this protection is lost leading to increase in the depth of gingival sulcus forming pockets for the deposition of invading organisms.

The results of the study show the change of non-keratinized sulcular epithelium to keratinized type in those groups of animals which were exposed to low frequency noise. The pattern of effect

TABLE 2

Comparison of mean thickness of sulcular epithelium among groups A, B and C.

*p value <0.05 significat is almost same in groups A and C. These findings indicate that it is the low frequency component of the noise which is the culprit for change in the type of sulcular epithelium. This change in the characteristic of sulcular epithelium may be due to continuous direct insult caused to epithelium due to mechanical effect of low frequency noise thus protecting the deeper layers from this insult.

Study gave a good insight into the problem of noise pollution affecting the livings but it is recommended that future study can be conducted by performing the study on fixed frequency with different sound intensity or stopping the LFN exposure and observe whether these effects are reversible.

CONCLUSION

This study concludes that

  1. Low frequency noise and normal animal house conditions induce keratinization of sulcular epithelium in mice.
  2. Damage to the sulcular epithelium causes disruption of its normal function of secretion of sulcular fluid leading to increased susceptibility to periodontal disease.
  3. This change occurs irrespective of the gender.

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  20. Caffesse RG, Karring T, Nasjleti CE. Keratinizing potential of sulcular epithelium. J Periodontol. 1977 Mar; 48(3): 140-146.

  1. Anatomy department, Army Medical College Rawalpindi.
  2. Head of Anatomy department, Army Medical College Rawalpindi of Surgery. The Aga Khan University Hospital, Stadium Road, Karachi.
  3. Assistant Professor of Anatomy, Army Medical College Rawalpindi.

Correspondence to:“Dr. Toqeer Ahmed” <drtoqeer@hotmail.com>

Dilemma Of Impacted Mandibular Third Molar Extractions: Review Of A Case

 

Malik Salman Aziz1                     BDS, FCPS, MFDS RCPSG, MFGDP(UK)

Munawar Alam Ansari2            MBBS, MPhil, PhD

Zahida Memon3                            MBBS, MPhil, PhD

Risks involved in removal of impacted mandibular third molars are, by far, much higher than the perceived risk of development of any condition compelling their prophylactic removal. Mandibular third molars, lying in close proximity to the most important sensory nerves especially the mandibular nerve, pose a considerable threat of possible neurological injury. Removal of impacted mandibular third molars especially if asymptomatic, is not desirable and has detrimental consequences affecting the patient’s quality of life. Damage to the inferior alveolar nerve may result in paraesthesias or abnormal sensations, hypoaesthesias, dysaesthesias and even anesthesia with or without taste disturbances. This paper reviews a case involving prophylactic bilateral extractions of impacted mandibular third molars in a male patient 26 years of age, the aftereffects that occurred and some directives to improved management and avoidance of such problems.

KEY WORDS: Third Molar, Mandibular nerve, Paresthesia, Anesthesia.

HOW TO CITE: Aziz MS, Maxood A, Hassan A. Dilemma of Impacted Mandibular Third Molar Extractions: Review of A Case. J Pak Dent Assoc 2013; 22: 237-240.

INTRODUCTION

Mandibular third molars being the most frequently impacted teeth have always been the oral surgeon’s prime targets for extraction. This school of thought is backed by myths of association of these teeth, with a high incidence of pathological lesions, anterior crowding, less trauma in cases of early extraction, and with the little risk of harm in removal. Although true to a certain extent, the above mentioned reasons do not justify the prophylactic removal of these teeth. The risks involved in prophylactic extractions of such teeth, when weighed against conservation, are far greater than the risks of development of any of the aforementioned conditions. Apart from the usual post surgical complications including pain, swelling, hemorrhage, trismus and malaise, mandibular third molar removal is associated with more serious conditions affecting the quality of life including, paraesthesias, hypoaesthesias, dysaesthesias (temporary or permanent), fractures of adjacent teeth or mandible, development of periodontal defects and even anesthesia. The most common pathology associated with impacted mandibular third molars is pericoronitis which if recurrent and/or unresponsive to treatment, necessitates removal.

A risk of development of cystic lesions around impacted teeth should be born in mind and weighed against the odds of development of physical and/or sensory disability which may be encountered after surgery. Patients with asymptomatic and impacted mandibular third molars should be recalled for continued follow up, but should not be encouraged to undergo a procedure involving considerable risk, affecting their quality of life unless there is a good evidence of patient’s benefit.

Presence and position of mandibular impacted third molars has been identified as one of the potential etiological factors of both anterior crowding and late lower arch crowding post orthodontic treatment. This hypothesis has been nullified by research work.1 Prevention of mandibular incisor crowding by the prophylactic removal of third molars is therefore not justified.

Highest risks of complication of mandibular impacted third molar removal have been shown to be between 25 to 34 years of age as compared to higher age groups.2

This case report signifies and enlightens how impacted mandibular third molar extractions can affect the quality of life and also explains how to avoid such events and manage the consequences.

CASE

A male patient 26 years of age, reported at the Department of Dentistry, Pakistan Institute of Medical Sciences with the complaint of numbness and occasional tingling on the entire right side of his lower jaw including the lower lip and chin, and on the left half of his tongue which also had no taste sensation. On history taking it was revealed that he had undergone surgery for the removal of both his mandibular third molars under general anesthesia, at a dental hospital abroad (location undisclosed). On examination of his presurgical panoramic tomograph and periapicals, it was revealed that both the mandibular molars were impacted, # 38 (FDI) being horizontal, while #48 (FDI) was mesioangular. Additionally both these teeth were in close proximity of the inferior dental canal as shown in fig.1. This finding was indicative of probability of trauma to the mandibular and lingual

Fig 1: Pre operative panoramic view

nerves during removal of the impacted teeth. On further questioning, the  patient also disclosed that, he being a flying officer at an international airline, was suffering from frequent and  excruciating episodes of pain, in his posterior mandibular region during flights only, which became the main reason for him opting to undergo removal  of both his wisdom teeth. There was no history of episodes of pain with infection and swelling, i.e. pericoronitis in the mandibular third molar regions.

On examination, the patient was afebrile but had trismus, and ulceration at the angle of the mouth (fig 2). The socket healing

Post operative Clinical Pictures

was normal. Thorough neurosensory examination was carried out in the form of pin prick and light touch sensation test, which confirmed the anesthesia in the areas innervated by right mandibular inferior dental nerve both intraorally as well as extraorally. Provocation taste test was conducted, which includes the placement of sugar salt and mustard on the patient’s tongue, to confirm the ageusia on the left anterior half of the tongue. It was concluded that the patient had anesthesia on the entire mandibular right side and diminished taste sensation on the left anterior part of tongue. Rest of the oral cavity had a normal presentation. There was however a crown in upper central incisor and a root treated maxillary right first molar which at the time of examination did not show any abnormality. The patient was otherwise fit and healthy.

The patient was reassured and was advised to have regular follow up with a prescription of Methylcobalamin 500µg thrice daily. He was also advised not to have hot and spicy food stuff, keep a check on his intra oral environment daily so as to detect any trauma to the mucosa which may be in the form of ulceration, and not to chew his lip in order to check for the presence of any sensation.

On first follow up appointment after 15 days the patient reported minute alleviation in symptoms, in the form of improvement in taste sensation, however paresthesia of gums and lip on the right side was the same. Neurosensory examination was again inconclusive. Patient was advised to continue treatment for 15 more days. On subsequent visit, patient reported some form of sensations at night on the left side but over all the condition remained the same. He was then referred to an oral and maxillofacial surgeon and neurologist for opinion and further management.

DISCUSSION

Mandibular third molars lie in close proximity to four most important nerves, namely inferior dental, lingual and mylohyoid and long buccal nerves. These nerves are at constant risk of damage during surgical removal of impacted mandibular third molars.

Conditions which necessitate impacted mandibular third molar removal include acute or chronic pericoronitis, presence of caries on the second molar or third molar itself, presence of cysts, periodontal disease of second molar, resorption of adjacent tooth caused by the impacted third molar, pre or post orthodontic treatment or pre orthognathic surgery.3

The incidence of third molar removal has always been high all over the world with prophylactic extractions topping the list.4-6 However since the newly published recommendations of British National Institute of Clinical Excellence (NICE), the trend for prophylactic removal of mandibular third molars has changed in the UK and has started to flip towards a more conservative approach in the US. The guidelines given by NICE specifically oppose prophylactic removal of impacted third molars.6

Removal of impacted mandibular third molars usually involves surgery under general anesthetic. Assessment of the factors such as depth of impaction, angulation of tooth, root curvature, ramus relationship, root divergence, number of roots, relative horizontal position, periodontal membrane space, and proximity to the inferior alveolar nerve must be kept under consideration during treatment planning, as they not only govern the difficulty of the procedure but also influence the post surgical management, outcomes and needs of the patient.7 Adverse events and complications of impacted third molar removal include effects from hemorrhage to numbness.

Barodontalgia is defined as dental pain elicited by changes in barometric pressure in an asymptomatic tooth. Dental caries, pulpitis, defective restorations, periodontal pockets, pulp necrosis, apical periodontitis, impacted teeth and mucous retention cysts have been identified as possible causes of the condition.8 Sometimes air crew patients and air passengers challenge the dental surgeon in treating several flight related conditions as was the case with current patient, who ended up having removal of both his asymptomatic impacted mandibular molars making flight discomfort the main reason. According to the patient, the side effects were conveyed to him but his profession led him into deciding for extraction. Last decision always remains with the patient, but dentists should always perform his /her duty in conveying the risks, benefits and prognosis of the treatment to the patient, taking written informed consent to avoid any unwanted situations in the form of law suits. Moreover ethical binding should always be remembered, as patient’s wants may sometimes disagree with it. In such situations, the patient should be referred for opinion to a specialist.

If removal of a mandibular impacted third molar in close proximity of inferior dental nerve is deemed necessary, apart from the conventional surgical techniques, a new approach has been developed, in the form of coronectomy of the third molar without removal of the entire tooth.9 This technique, first described in 1989, 10 has the advantage of avoiding a longer and more invasive surgery along with sparing the mandibular nerve, which exempts the patients from unnecessary trauma. This procedure involves the removal of the crown of the third molar thus promoting and facilitating the eruption and movement of retained roots away from the inferior dental canal. Once the root portion of the tooth has erupted to a safe level above the inferior dental canal, it can be removed whenever required by a second surgery 11.The apparent undesirability of this procedure would definitely be, that of patient undergoing two surgeries including administration of local anesthetic; however it has the advantage of avoiding extreme effects on quality of patient’s life, along with refraining from probable general anesthesia.

Here a debate also arises, igniting an argument, as to what would be the fate of the pulp tissue and the remaining roots which have been left inside the bone? Well the answer has been provided by research on retention of retained vital roots,12-14 which states that retained roots remain vital and may in time get covered by osteocementum and bone. 12-14 Therefore it is advised in literature, not to treat or medicate the retained root pulp after coronectomy.11, 15

Methylcobalamin is a neurologically active form of vitamin B12, which has provided promising results in treatment of patients with various nerve injuries; however its effectiveness in all cases cannot be guaranteed. Besides it has disturbing side effects and therefore should be discontinued if patient reports any symptoms like hypersensitivity reactions, gastrointestinal problems in the form of nausea and vomiting or anorexia and diarrhea16- 17.

Although the incidence of mandibular third molars in extreme proximity of inferior dental nerve is less, the clinician must keep in mind its possibility, especially if pre operative radiographs indicate a close relation. All cases of impacted mandibular third molars in close relation to the mandibular nerve must be referred for specialist management by oral and maxillofacial surgeon.

In general practice cases of nerve injury, if report to the clinician, must be considered for a referral to a neurologist and specialist oral and maxillofacial surgeon for management. The reparative role of vitamin B12/methylcobalamin in nerve injuries should be further investigated.

REFERENCES

  1. Harradine NW, Pearson MH, Toth B. The effect of extraction of third molars on late lower incisor crowding: a randomized controlled trial. Br J Orthod. 1998. 25(2): 117-122.
  2. Osborn TP, Frederickson G, Small IA, Torgerson TS. A prospective study of complications related to mandibular third molar surgery. J Oral Maxifac Surg. 1985: 43: 767-769.
  3. Bolondeau F, Daniel NG. Extraction of mandibular third molars: Postoperative complications and their risk factors. J Can Dent Assoc. 2007; 73(4): 325.
  4. Landes DP. The relationship between dental health and variations in the level of third molar removals experienced by populations. Community Dental Health. 1998; 15: 67-71.
  5. Shepherd JP, Brickley M. Surgical removal of third molars. Br Med J. 1994; 309: 620-621.
  6. Friedman JW. The prophylactic extraction of third molars: A public health hazard. Am J Public Health. 2007; 97(9): 15541559.
  7. Akadiri OA, Obiechina AE, Arotiba JT, Fasola AO. Relative impact of patient characteristics and radiographic variables on the difficulty of removing impacted mandibular third molars. J Contemp Dent Pract. 2008; 9(4):51-58.
  8. Zadik Y. Aviation dentistry: current concepts and practice. Br Dent J. 2009; 206(1):11-16.
  9. Renton T, Hankins M, Sproate C, McGurk M. A randomized controlled trial to compare the incidence of injury to inferior alveolar nerve as a result of coronectomy and removal of mandibular third molars. Br J Oral Maxfac Surg. 2005; 43(1): 7-12.
  10. O’Riordan BC. Uneasy lies the head that wears the crown. Br J Oral Maxillofac Surg 1997; 35:209.
  11. Pogrel MA, Lee JS, Muff DF. Coronectomy: A technique to protect the inferior alveolar nerve. J Oral Maxillofac Surg. 2004; 62: 1447-1452.
  12. Johnson DL, Kelly JF, Flinton RJ, Cornell MT. Histologic evaluation of vital root retention. J Oral Surg 32:829, 1974.
  13. Whitaker DD, Shankle RJ. A study of the histologic reaction of submerged root segments. Oral Surg Oral Med Oral Pathol 1974;37:919-last page, 1974.
  14. Plata RL, Kelln EE, Linda L. Intentional retention of vital submerged roots in dogs. Oral Surg Oral Med Oral Pathol 1976 42:100-last page, 1976.
  15. Frafjord R, Renton T. A review of coronectomy. J Oral Surg 2010; 3: 1-7.
  16. Jalaludin MA. Methylcobalamin treatment of Bell’s palsy. Methods Find Exp Clin Pharmacol. 1995;17:539-544. 17. Yaqub BA, Siddique A, Sulimani R. Effects of methylcobalamin on diabetic neuropathy. Clin Neurol Neurosurg. 1992;94:105-111.

  1. Consultant in Restorative Dentistry University Medical & Dental College Faisalabad.
  2. Professor, Head of Department of Dentistry Pakistan Institute of Medical Sciences, Islamabad.
  3. Associate Professor, Department of Prosthodontics Margalla College of Dentistry, Rawalpindi.

Correspondence to:“Dr. Malik Salman Aziz” <drsalmanaziz@gmail.com >

Developmental Enamel Defects: A Review

 

Amna Tariq1                                  BDS, FCPS

Munawar Alam Ansari2            MBBS, MPhil, PhD

Zahida Memon3                            MBBS, MPhil, PhD

Dental enamel is an unusual tissue in that once formed it is not remodeled, unlike other hard tissues such as bone. Because of its non remodeling nature, alterations of enamel during its formation are permanently recorded on the tooth surface.

As enamel formation can be affected by many factors, the changes induced in the enamel formation, can provide clues as to the timing and nature of these events. Enamel defects may thus be studied as a marker of many adverse biological events occurring during the time of its development. One such developmental defect of the enamel occurring due to changes in the environmental factors causing permanent damage of the enamel is Molar Incisor Hypomineralization (MIH).

MIH presents the clinical picture of hypomineralization of systemic origin affecting one or more first permanent molars (FPMs) that are associated frequently with affected incisors. Systemic conditions or environmental insults during the child’s first 3 years have etiological associations. In treatment modalities complex care may involve, including the management of behavior and anxiety of affected children and aiming to provide a durable restoration under pain-free conditions. The challenges include a number of other requisites such as adequate anesthesia, suitable cavity design, and choice of restorative materials.

The purpose of this review is to comprehend the knowledge about the diagnosis, prevalence, putative etiological factors, and features of hypomineralized enamel in molar incisor hypomineralization and to present a sequential approach to management.

KEY WORDS: MIH, PFM, Hypominerelization.

HOW TO CITE: Tariq A, Ansari MA, Memon Z. Developmental Enamel Defects: A Review. J Pak Dent Assoc 2013; 22: 241-250.

INTRODUCTION

Amelogenesis, is regulated by ameloblasts and a multifaceted process that requires secretion of certain matrix proteins like amelogenins, amelins, enamelins and tuftelins and of the prior formation of dentine 1,3.  Dental enamel formation occurs in various phases in the primary as well as in the permanent dentition.according to few studiesthere are two steps 1,2 i.e. the secretory phase [or matrix formation] and the maturation phase while other authers add an intermediate or transitional phase 4. According to Lacruz amelogenesis can be classified as pre-secretory, secretory, and maturation stages 3. Genetic and environmental factors have marked influence on these processes; consequently, may result in developmental enamel defects (DED) from any event disturbing these phases. Metabolic or systemic alterations during the formation of dental crown, reflects a permanent impression of systemic disturbances, such as prolonged periods of high fever, nutritional deficiencies, congenital factors, infections, and certain medications can affect enamel-forming cells. A number of known conditions such as diseases, metabolic anomalies, and environmental factors can modify normal enamel development 5,8 alteration resulting from varied turmoil during the process of amelogenesis considered as Developmental enamel defects. DED can be further classified according to their manifestation such as demarcated opacities, diffuse opacities, and hypoplasia 6 primary and permanent dentitions both may be affected, and be associated even to single long-lasting disturbances or isolated events 9. While according to some authors there are linking events in the deciduous teeth consequences observed in the permanent set of dentition 10,13.

Dental enamel is dissimilar to other hard tissues such as bone in the fact that once formed it is not amend14. Knowing its non amending nature, variations of enamel formation is permanently recorded on the tooth surface, the alterations induced in the enamel formation, can give evidences as to the timing and nature of these events14. Thus many adverse biological events may be reflected as Enamel defects and thus may be cosidered as a marker of unfavorable measures occurring during the time of its development14.

EPIDEMIOLOGY

The literature of the last fifteen year and epidemiologic data is very limited and turned mostly to studies of prevalence. studies available on the frequency of hypoplasia of the dental enamel in the present-day populations demonstrate the link between the socio-economical conditions and the prevalence of this defect15. Data from the developed countries reflects the incidence of this condition for an average of 10%, while in the developing countries the same incidence is markedly higher than the 50% 15. Data from tha studies undertaken between the year 1987 and the 2001 are of difficult interpretation because they recorded as secondary result only and do not have objective as the study of prevalence. According to that data they claim that it varies within an ample period of time, included between the 2.8 and 2.5%, up to assumption of a more reliable and constant value that is around the 15%, instantly after such time term 16,28 on the contrary the reflection of more recent epidemiological studies seem to present that the MIH prevalence is increasing day by day 19. According to the data presented in the study  on 3518 Greek children, aged between 5.5 and 12 years, results that: the 10.2% of them (58.6 female and 41.4 male) present Molar Incisor Hypominerelization (MIH), while the total number of teeth affected almost equal to 1286, of which 776 molars and 510 incisors In the 28.4% of the children influenced by MIH are interested only molars while in the 71.6% incisors and molars both. While the different type of association of the affected teeth noticed that resulted as: 4 molars 2 incisors (23.5%), 4 molars 4 incisors (16.8%), only 4 molars (15.1%), only 2 molars (9.7%) with a main involvement of the maxillary elements in contrast to the lower jaw. Such study also demonstrates that some pathologic condition in progressive in relation to the age because the under observed dental tissue are affected by a post eruptive repartition of the enamel, and determine that the gravity of the MIH increases in a way proportional to the chronologic age 19,30With respect to the gender diffrences the major part of the studies undertaken between the 2001 and the 2007 demonstrate that it does not exist any difference of distribution among the two sexes 18,21-25.

On the contrary, recently some Authors report a major evidence charged to female sex, but with no demonstration of causal relationship 27. There are a number of studies undertaken to establish the average value, per child, of tooth affected by MIH presents that it varies from 5 to 5.7 elements per individual; further more they highlighted that the damages involving the first permanent maxillary molars are the more serious as well as the more frequent 18,20,21,23-27,29.

CLINICAL FEATURES

By definition MIH is a hypomineralized defect of the first permanent molars, frequently correlated with affected incisors 30. It is observed that the number of affected first permanent molars is variable per patient from one to four and expression of the defects may vary from molar to molar 30. Intact opacities

Table 3: Clinically differentiation between MIH, Amelogenesis Imperfecta and Fluorosis.

can be found on one molar within one patient, while the other molar may have large parts of the enamel break down soon after eruption 30. When a severe defect is found within a subject, it is likely that the contralateral tooth is also affected 30. In connection to molars opacities may be found in the upper and sometimes the lower

Fig 1: Affected incisors with well demarcated yellow brown areas.

Fig 2: Affected Permanent First Molars.

and upper incisors, (Figure 1). The possibility of defects to the maxillary incisors appears to increase when more first permanent molars have been affected 30. The defects of incisors are usually without loss of enamel substance.

Clinically, the hypomineralized enamel appears to be soft, porous and look like discoloured chalk or Old Dutch cheese. With respect to colour the enamel defects can diverge from white to yellow or brownish and it always demonstrate a sharp demarcation between the affected and sound enamel 3 1 (Figure 2). The hypominerelized weak and porous, brittle enamel can easily chip off under the masticatory forces. Sometimes, posteruptive enamel breakdown can occur so rapidly after eruption that it seems as if the enamel was not formed initially 31. It appears as hypoplastic enamel after occurrence of the post-eruptive enamel breakdown. Clinically hypoplasia presents with the smooth borders to the normal enamel, whilst in posteruptive perid

Table 1: Review of the studies from the year 1992-2010, related to MIH.

enamel breakdown occurs and the borders of the normal enamel appear irregular 31. MIH can sometimes be confusing with fluorosis or amelogenesis imperfect 31.
In fluorosis as its opacities are diffuse opacities that can be well differentiated from are demarcated opacities of MIH (fluorosis is caries resistant and MIH is caries prone). Choosing between Amelogenesis Imperfecta (AI) and MIH as a diagnosis seems a matter of definition: it should be stressed that, only in very severe MIH cases, the molars are equally affected and mimic the appearance of AI 32. Mostly in MIH, the appearance of the defects will be more asymmetrical in the molars as well as in the incisors. In AI, the molars may also appear taurodont on radiograph and there is often a history of family onset 31.

ETIOLOGY

The uneven appearance of MIH molars within individuals depictes that a systemic disorder at a very specific stage affects the dvelopment of ameloblasts. According to the current data the researchers hypothesize that, in the case of MIH, the ameloblasts are affected in the early maturation stage, or maybe even earlier atthe late secretory phase.

In the recent studies, various causes for MIH molars, such as environmental conditions, respiratory tract problems, perinatal complications and dioxins have been suggested 17,30,32,33. Other factors responsible for MIH availble in the litrature are oxygen starvation of the child combined with a low birth weight, calcium and phosphate metabolic disorders and frequent childhood diseases 34-36. Vaccines given during early childhood have also been suggested as a possible cause but no data are available to validate this. The use of antibiotics has also been implicated, but antibiotic use is in most cases related to occurrence of diseases, so it is difficult to distinguish whether the association with MIH is caused by the antibiotic or by the illness itself. There are contradictions in the results of the different studies abou it. A number of studies relate the problems during pregnancy and birth with the MIH, while in other studies show no differences concerning the health of mother and child during pregnancy and birth of the children 33,36 . The latter study indicates a more childrelated cause originating after birth. The influence of prolonged breast-feeding could not be demonstrated in all studies 17,36-38. It is likely that several unknown contributing factors are involved resulting in a number of possible causes37, 38.

A study conducted in Greece of 151 MIH children resulted that 78% had experienced medical problems: (1) prenatally (19%); (2) perinatally (44%); and (3) neonatally (22%) 41. Only 15% of the children did not appear to have a putative etiological factor in their history 39.

Studies available do not suggest any causal relationships because it cannot be assigned definitively from studies relying on parental recall of medical and dental events in their child’s first 3 years 40, 41. It becomes more difficult to determine the aetiological factor when it is associated with a number of medical problems in this period. Although a number of causative factors may contribute to MIH but the threshold level needed to cause enamel defects and at which sensitive stages of amelogenesis is unknown42. It is assumed that systemic illnesses may not produce a developmental defect of enamel when experienced singly, and two or more concurrent conditions may act synergistically to produce a defect42. It is also in accordance to the study of 53 Swedish children with 22q11 microdeletion syndrome 43. Phenotypically, this multiple anomaly has a characteristic facies, and may include congenital heart defects, velopharyngeal insufficiency which may include cleft palate, immune defficiencies, and difficulty in feeding, hypocalcemia, learning disabilities, behavioural problems, and skeletal, neurologic, and gastrointestinal abnormalities 43. Of 47 affected children, 3 (6%) had EH in the permanent dentition and 16 (34%) had hypomineralized permanent teeth. Computerized inductive analyses showed that the EH of permanent and primary teeth correlated with prematurity and heart defects (30%) and enamel hypomineralization correlated with frequent preschool age infections and heart defects (43%) 43.
Infectious conditions common in the first 3 years, such as upper respiratory diseases, asthma, otitis media, tonsillitis, chicken pox, measles, and rubella, appears to be associated with MIH. 44, 45. It is also reflected in the retrospective study of 21 Dutch MIH children, 67% had suffered from bronchitis, asthmatic bronchitis, pneumonia, and upper respiratory tract infections8. The usage of antibiotic has also been implicated. Due to the harmony of disease and antibiotic therapy, though it is difficult to ascertain whether the MIH was associated with the disease or the antibiotic 45. Litrature shows that children with poor general health and systemic conditions are more likely to have developmental defects of enamel 46, 47.
As the minerelization of Permanent First Molars (PFM) commences soon after birth, a persistent systemic derangement postnatally may affect enamel mineralization 50. Preterm birth can be associated with a number of systemic conditions such as respiratory difficulties, hyperbilirubinaemia, metabolic disturbances including hypocalcemia and hypoglycemia, haematological disorders, patent ductus arteriosus, and intracranial hemorrhage 48. A study of 32 Finnish children 9 to 11 years old found enamel defects in 36% of children born fullterm and 84% of children born preterm 49. It is suggested that the severity of enamel defects increased with decreasing gestational age and lower birth weight 50.
A number of clinical and laboratory studies reflects the associations between the presence of polychlorinated dibenzo-p-dioxins (PCDDs) in breast milk and enamel hypomineralization 51,52. it belongs to a class of environmental pollutants known as polyhalogenated aromatic hydrocarbons 51 that results in long term persistent exposure in humans and accumulation of PCDDs in tissue lipids and in the food chain 53.
Other clinical studies have not found any associations between dioxin compounds in breast milk and were born preterm or who were exposed to certain environmental contaminants may be at risk for MIH.

 Tooth discoloration related to drug:
There are a number of known drugs responsible for producing extrinsic or intrinsic tooth discoloration.

(a) Extrinsic Tooth Discoloration related to Drug:
This type of discoloration appear after the tooth has erupted in the oral cavity, in this case drug is responsible for subsequent cause of superficial discoloration, toothbrushing or professional cleaning are the methods for its elimination. According to number of authors there are a number of drugs that are wellknown to be causing extrinsic discoloration include chlorhexidine 54-56, oral iron salts in liquid form essential oils 57 and Coamoxiclav58. Netherlands Pharmacovigilance Foundation (LAREB) published abundant data from January, 1991, until June, 1995, of oral use of liquid medication causing yellow to brown tooth discoloration out of which 84% involved
antibiotics, particularly amoxicillin 59. Another source of data depicts the tooth discoloration problem accredited
to the use of drugs, frequently to the use of amoxicillin and doxycycline or minocycline. Antimicrobial agents mostly cause the Pseudo-discolorations; mechanism may involve the chromogenic precipitates accumulation in the pellicle, or by chromogenic micro-organisms overgrowth59. With the increasing frequency of methicillin-resistant Staphylococcus aureus in immunocompromised hosts, clinicians are increasingly prescribing the oral antimicrobial linezolid, an oxazolidinone. A case of an immunocompromised 11-year-old girl was reported with cellulitis and the development of superficial discoloration of her lower anterior teeth after receiving linezolid for 28 days 60.

(b) Intrinsic Tooth Discoloration related to Drug:
It is Permanent type of tooth discoloration occurs when the drug interferes with odontogenesis. A number of causative agents are known but we will discuss only Fluorides and Tetracyclines.
(i) Fluorides
Inorganic fluorides plays a pivotal role in reducing the extent and severity of dental caries in children and adults59. It also has some unfavorable effects in humans, That depends upon the level and source of exposure59. there are many sources of getting fluoride in routine like water, toothpaste, prescribed drops, and tablets, upon which the discoloration depends specially at the time of tooth development stages like formation and maturation phase. Over exposure to fluoride ion causes Dental fluorosis, which is the most common adverse effect and may end up to the permanent hypomineralization of enamel.This type of hypomineralization can be recognized clinically in its mildest form as small, barely visible, white flecks found mostly on cusp tips and on facial surfaces of the permanent teeth61. While the severity ranges from white opaque areas to darkly stained and pitted enamel, 61 that is visible on most surfaces of permanent teeth. Exposure to fluoride in early maturation stage of tooth development is considered to be critical for fluorosis to evident61. Dental fluorosis is a dose-dependent condition, according to Dean in 1942, that shows a direct relationship. The higher the level of exposure during tooth development, may lead to the more severe
fluorosis62. The normal range of fluoride to be taken in tooth development period i.e. from approximately birth to 8 years of age, is in the range of 0.03 to 0.1 mg/kg body weight per day 62.

(ii) Tetracyclines
It was hypothesized by Olsen and Riley hypothesized that tetracycline may cause permanent tooth discoloration in 1960’s63. Subsequent to this hypothesis many clinical and laboratory studies exhibited the association that tetracycline make an irreversible bond to calcified tooth structures, if it is exposed during the calcification stage of hard tissue63. Today it is a proven fact that Tetracyclines are result in the discoloration of hard tissue of the body when prescribed during its development. Discoloration of deciduous teeth may occur in result to exposure to tetracycline during the second or third trimester of pregnancy. During development, the teeth may become bright yellow while the stains will later turn to grey or brown over a period of time62. Use of Tetracycline is prohibited to the children under the age of eight year as the majority of mineralization of the permanent dentition is incomplete until a child is eight years of age (excluding third molars). It is reported that (www.Continuing Education.com, 2004). Data suggests that if the total dosage administration of tetracycline is over 3 g, or treatment exceeds 10 days at the age of tooth development, it will lead to tooth discolcoration (www.Continuing Education.com, 2004). The type and severity of discoloration may vary depending upon the specific tetracycline used 62. According to Driscoll et al., 1993 yellow discoloration was caused by Tetracycline and oxytetracycline, whereas chlortetracycline produces a grey-brown discoloration. Tetracyclines for endodontic therapy in the form of Ledermix-triamcinolone acetonide and demethylchlortetracycline may also cause dark greybrown discoloration within the tooth64. On the other hand, minocycline and ciprofloxacin, have also been reported to cause tooth discoloration.

Preventive management
Children with MIH repeatedly experience pain, sensitivity and aesthetic concerns when their incisors are affected. A management approach based on 6-steps is proposed (Table 2). It is suggested that MIH risk children should be diagnosed prior to eruption of PFM, this diagnosis should based upon a relevant history of assumed etiological factors in the first 3 years and from careful study under magnification of the unerupted molar crowns on any available radiographs. Knowing the fact that during PFM eruption, the hypomineralized surface is very susceptible to caries and erosion. The child’s diet should be assessed and appropriate recommendations made for reduction
of cariogenicity and erosivity of the diet. Meticulous oral hygiene should be maintain. Desensitizing toothpaste can be recommended along with Remineralization therapy should commence as soon as the defective surface is accessible, in order to produce a hypermineralized surface layer and to desensitize the tooth 41,65. Process of remineralization and desensitization may be accomplished with casein phosphopeptide-amorphous calcium phosphate

 (CPP-ACP) oral care products. The CPP-ACP can interact with fluoride ions, producing an amorphous calcium phosphate stabilized by CPP at the tooth surface and providing soluble calcium, fluoride, and phosphate ions to promote remineralization with fluorapatite that is more acid resistant 66.
Topical fluoride available as varnishes/ gels, delivered as concentrated, can remineralize enamel, enhance resistance and reduce sensitivity to demineralization by providing a reservoir of fluoride ions for redeposition as fluorapatite during remineralization 67.
Regular oral hygiene strategies can be instituted as remineralization and desensitization of the affected molars occurs.
Glass ionomer cement sealants can provide caries protection and reduce surface permeability for partially erupted PFMs where moisture control is suboptimal. However, such sealants may need rebuilding later because of poor retention , reconstruction with a resin-based sealant when optimal moisture control is possible is recommended 68, 69. If preventive care is not provided , hypomineralized PFMs are at risk of PEB in the acidic and masticatory challenges of the oral cavity. PEB will lead to increase the porosity of subsurface enamel or dentin and will result in teeth to become sensitive to cold air, warm water, and toothbrushing 37. Moreover, deprived oral hygiene will lead to plaque retention and promotes rapid caries development 70.

CONCLUSION

In conclusion it can be said that the prevalence of MIH appears to be increasing, and managing affected children is a general problem for pediatric dentists. The etiology is unclear and may be multifactorial, in fact the children born preterm and in their first 3 years with poor general health or systemic conditions may develop MIH. The early identification of such children may permit monitoring of their PFMs so that remineralization and preventive measures can be considered as soon as affected surfaces are visible in oral cavity. In order to provide the complex care, it must address the child’s behavior and anxiety, seeking to provide durable and pain-free restorations. It is recommended that it is necessary to consider further research to clarify etiological factors and improve the durability of restorations in affected teeth.

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  1. Department of Pharmacology, Ziauddin University, Clifton, Karachi.
  2. Department of Pharmacology and Therapeutics, Liaquat University of Medical and Health Sciences, Hyderabad.
  3. Department of Pharmacology, Ziauddin University, Clifton, Karachi.

Correspondence to:“Dr. Meena Kumari Rathi” <mk_das@hotmail.com>

Altered Cast Technique: Improving Tissue Support For The Distal Extension Bases

 

Haroon Rashid1                                  BDS, MDSc

Fahim Ahmed Vohra2                      BDS, MDSc

Amir Shehzad5                                    BDS

Altered cast impression technique is commonly used for the mandibular distal extension partially edentulous arches. The technique is relatively simple but requires increased chair-side time and laboratory cost. Oral tissues that have been displaced during the impression procedure attempt to regain the anatomic form and they may get inflamed if the denture base does not permit them to do so. The aim of this case report is to portray an approach of recording a minimal tissue displacing altered cast impression using addition cured silicone material.

KEYWORDS: Distal extension bases, Stability, Addition Cured Silicones, Altered Cast Technique, Corrected Cast Technique

HOW TO CITE: Rashid H, Vohra FA, Shahzad A.  Altered Cast Technique: Improving Tissue Support for the Distal Extension Bases. J Pak Dent Assoc 2013; 22: 234-236.

INTRODUCTION

Distal extension removable partial denture (RPD) depends largely on the residual alveolar ridge for support, stability and retention. These dentures only have partial   support from teeth as their bases may be the extensions covering the ridge distal to the last abutment tooth. The tooth supported RPDs have an advantage of presence of a direct retainer whereas this is lacking in the prosthesis fabricated over distal extension bases. Support from the residual alveolar ridge as described by Carr and Brown (1) will depend on several factors which include the quality of the residual alveolar ridge and its contour, extent of the ridge covered by the RPD, the accuracy of the impression, fitting accuracy of the denture, RPD design and the total occlusal load applied during function.

An altered cast impression procedure to improve the support of distal extension removable partial dentures is widely taught, but not often used in dental practice (2). Also known as the corrected-cast technique (3) the technique requires an additional step for both the dentist and the dental technician. It offers several advantages which include maximum stability, minimal stress on abutment teeth, and more predictable occlusion (3). Other benefits include reduction of the number of post operative visits, preservation of the residual ridges and decreasing the food impaction. The following paper outlines a quick and easy technique for constructing an altered cast for an RPD.

CASE REPORT

A 53 year old medically stable female patient attended the outpatient department of ZiauddinCollege of dentistry complaining of missing posterior teeth in the lower arch. The patient was wearing an acrylic partial denture which was loose and ill fitting. The denture had inadequate base extensions and poor tissue adaptation due to which there were signs of minor trauma to the soft tissue covering the crest of the alveolar ridge. No further signs of abnormalities were detected during intra-oral and extra-oral examination and it was decided that a new cast partial denture (CPD) is provided to the patient using the alteredcast technique once tissue healing is adequate. Option of implant retained fixed partial dentures was given to the patient but the patient could not afford the expense of the treatment. The patient decided to pursue the treatment plan which included the fabrication of a lower CPD. A step by step procedure is outlined with reference to various clinical and laboratory stages during the treatment:

Stage 1:

Maxillary and mandibular impressions were obtained using irreversible hydrocolloid (Cavex CA37?, Holland BV) and upper and lower study casts were obtained. Mandibular study casts were placed on a stage of a dental surveyor and surveying was carried out after which the design of the cast metal framework was finalized.

Stage 2:

Mouth preparation was done intraorally and final impressions of both the arches were recorded using medium bodied addition cured silicone (Zhermack Elite Monophase) using custom made trays. Master casts were obtained and design finalized. Investing and casting procedures were performed in the laboratory and the completed framework was checked to ensure that it fits the casts accurately (Fig 1).

1- Mandibular metal framework

Stage 3:

The cast metal framework was tried intra-orally for accuracy of fit and once this was done, an acrylic resin custom made trays were fabricated to the mandibular framework (Fig 2.). Border

2- Acrylic resin tray attached to metal framework

3- Border moulded tray

moulding was performed using green stick tracing compound (Fig 3). (Metrodent tracing sticks). Tray adhesive (Caulk tray adhesive, Dentsply) was applied over the impression surface of the tray and the final impression was taken using light bodied silicone (3M ESPE Express). During seating of the loaded tray, gentle finger pressure was applied over the areas of the framework which only came in contact with the teeth and not to the tray itself (Fig 4). It was ensured that the framework remained stable and did not move until the impression material was set.

4- Final Impression with light bodied silicone

Stage 4:

This was the stage when cast was altered in the laboratory. Beading of the final impression was done (Fig 5) and two saw cuts on the cast were made perpendicular to each other on either side of the saddle areas (Fig 6). Grooves were placed on the cut surface of the cast so that retention of the newly poured stone could be improved. The framework was seated completely on the cast, fixed using sticky wax and boxing procedure was performed (Fig 7). The final impression was poured using die stone and the working altered cast was removed (Fig 8). The usual remaining steps of denture fabrication were carried out, denture was delivered to the patient and post operative instructions were given.

DISCUSSION

Free end saddles are liable to be displaced under occlusal pressure. This is as a result of the displaceability of the mucosa of the free end saddle. The altered cast technique was a popular technique that was introduced in an attempt to overcome the problem. Oral tissues that have been overly displaced during the impression procedure attempt to regain their anatomic form and if the denture base does not permit them to do this, the tissues become inflamed followed by impaired physiological function. Tissues which are minimally displaced by impression materials respond favorably to the additional load applied. In the current case, it was aimed to improve the tissue support for the distal extension base by minimally displacing the soft tissues during

5- Final impression with beading

6- Casts with two saw cuts perpendicular to each other

7- Boxed Impression

the impression procedure. Zinc oxide eugenol paste or low viscosity silicone is usually placed in the customized tray and the framework is placed into the mouth and the impression taken with pressure only on the support elements of the framework resting on teeth. Low viscosity silicone was preferred over zinc oxide eugenol paste in the current

8- Working Altered Cast

case because if offers many advantages which include good tear strength, adequate working time, high accuracy, minimal distortion upon removal and excellent dimensional stability(4). However, they are expensive, require tray adhesive prior to their use and are hydrophobic thus; moisture control may be difficult to achieve. Altered cast impression technique is commonly used for the mandibular distal extension partially edentulous arches (Kennedy Class I and Class II). This technique is not common to be used in maxillary arches because the nature of the masticatory mucosa and the amount of form tissue support.

CONCLUSION

The altered cast technique is relatively simple but requires increased chair-side time and laboratory cost. However, considering the benefits of this technique, it is recommended that clinicians should incorporate it in their routine prosthodontic management of specific patients especially in those cases where implant therapy cannot be performed due to medical and dental contraindications.

REFERENCES

  1. Carr AB, Brown DT. McCraken’s Removable Partial Prosthodontics. 12th Edition. Mosby: 2011. Chapter 16. P 232.
  2. Frank RP, Brudvik JS, Noonan CJ. Clinical outcome of the altered cast impression procedure compared with use of a onepiece cast. J Prosthet Dent. 2004 May;91:468-476.
  3. Garcia EE, Evans JG. Removable partial dentures: the alteredcast technique. J Dent Technol. 1998;15:25-29.
  4. Forrester-Baker L, Seymour KG, Samarawickrama D, Zou L, Cherukara G, Patel M.A comparison of dimensional accuracy between three different addition cured silicone impression materials. Eur J ProsthodontRestor Dent. 2005;13:69-74.

  1. Assistant Professor, Department of Prosthodontics, Ziauddin College of Dentistry, Karachi, Pakistan.
  2. Assistant Professor, Department of Prosthodontics, King Saud University, Saudi Arabia.
  3.  Ziauddin College of Dentistry, Karachi, Pakistan.
    Correspondence to:“Dr. Haroon Rashid Baloch ” <haroon.rashid@zu.edu.pk