Vol. 25 No. 02 Apr-Jun 2016

Muhammad Badar Munir1               BDS, MCPS, FCPS
Muhammad Salman Rashid2          BDS
Sadaf Qadeer3                                       BDS, FCPS
Saira Yousuf Dar4                               BDS, FCPS                                   

INTRODUCTION

Enamel hypoplasia refers to a developmental disorder of tooth enamel that is characterized by an abnormal matrix formation. Clinically it presents as manifestation of yellow pits in the cervical and middle third of the teeth. Discoloration may also be evident. Compromised tooth structure causes sensitivity and rough surface favors retention of plaque. Research shows not only quality but the quantity of the tooth substance is also affected2-3. According to the development there are two varieties of Enamel hypoplasia; hereditary and acquired. Both can affect either set of dentition. Ectodermal disturbance during embryonic period contributes to the hereditary type defect. This type of defect mainly confined to enamel. Acquired hypoplasia usually affects both enamel and dentin. Infections, exposure to chemicals, birth defects and medications are listed factors. The disturbance in nutrition (vitamin A, C and D) and viral infection are contributory to this variety of Enamel hypolplasia. Clinical hypoplasia can be categorized as hypoplastic type or hypocalcified type. Hypoplastic teeth show a rapid breakdown of the enamel, which can be extremely sensitive. This could manifest in few months while the tooth is still erupting. The hindrance in cleaning in a partially erupted tooth may be further complicated by hot and cold sensitivity. This often causes plaque retention and more prone to carious tooth decay. Usually first permanent molars are affected, exfoliation of primary molars does not precede their eruption, so children and parents are often unaware of their presence and thus they do not seek treatment until it is symptomatic. The sensitivity is not common among incisors as it is on molars, however they frequently affected esthetically4 .

FEATURES OF ENAMEL HYPOPLASIA

1) Easy wear of enamel due to abnormal quantity.

2) Incisal edges and occlusal surfaces of molars may be discolored because of extrinsic staining.

3) Fluorosis also damages the enamel during tooth development and exhibits tooth discoloration.

CASE REPORT

A 23 year old otherwise healthy female presented to our institution with the complaint of transient hot and cold stimuli in tooth 16 and 46. However, she was more concerned with the appearance of her front teeth and reported their form as unpleasing. For the presenting complaint of pain in 16 and 46, the patient was suggested RCT for both teeth. Root canal treatment was performed for the teeth and amalgam restoration placed. All records of the procedure were maintained. Her maxillary incisors and molars showed surface pitting associated with dark brown stains at incisal edges. A similar pattern was observed on the molars, where the buccal surfaces were pitted and loss of enamel has resulted in the formation of sharp cuspal edges. Mandibular arch was also involved which showed staining of incisors and molars similar to maxillary arch. History of the patient revealed extended use of medications in early childhood (around the age of 3 years)for fever. Her parents did not remember the condition or the name of the medicine given at that time. For management of her current problem of dental esthetics, various treatment options were discussed. Those include:

1) Full ceramic crowns for incisors and molars.
2) Ceramic veneers for anterior and cast (or PFM) crowns for molars
3) Direct composite restoration for anterior and cast (or PFM) crowns for molars

All options were discussed with the patient and her family. Discussions led to adoption of direct composite veneers in the aesthetic zone while molars would be restored with PFM. Photographs were taken preoperatively. Teeth were scaled and polished to remove stains and to get the proper shade match of composite. Rubber dam was applied. Teeth were etched with 37% phosphoric acid for 20seconds, washed with water, dried with air and universal adhesive (3M ESPE ) applied. Than light curing composite (shade A-2 ;3M ESPE, NANOHYBRID) was placed in increments on the facial surface of teeth. Curing was done for 60 seconds as per manufacturer’s instructions. The composite facing was polished using a polishing disc (3M ESPE). Post-operative photographs were taken to assure the quality of treatment. Patient was advised for PFM crowns for molar restorations. The patient was satisfied with the outcome and was kept on three months follow-up visits.

DISCUSSION

The causes of MIH are not well defined. Multiple factors have been associated with the condition. Children who are born, prematurely and those with poor general health or systemic conditions in their first three years may develop MIH5- 6 .While clinical evaluation revealed that mineralized structures are compromised as surface irregularities on defected parts favor the plaque retention which create hindrance in the management of esthetically compromised teeth7. Minimally invasive restorative techniques provided a conservative approach towards the management of compromised tooth substance7-8. Various approaches like: Enamel abrasion, Dental whitening/bleaching, composite veneering may be performed to manage MIH depending upon the on severity of disorder9-10. Tooth colored restorations are esthetically pleasing, as they match closely with the natural tooth shade10. Composites are not only the affordable modality but gives natural appearance. No patient discomfort is reported when using composites direct veneers. The rationale of restoring the hypoplastic defects is to redirect the forces during mastication (occlusion) and also to give patient self confidence in terms of aesthetics.

CONCLUSIONS

The conservative rehabilitation of the enamel hypoplasia involving the incisor and molars, the direct composite veneers seems to be the most reasonable option to restore the esthetics. This is an acceptable and affordable treatment modality.

REFERENCES

1. Mamoon M, Ahmad M, Amhem DA, Ahmad AL. Dental anomalies in children in North Jordan. Pak Oral Dent J. 2011; 31(2): 309-313.
2. Brook AH, Fearne JM, Smith J. Environmental causes of enamel defects. Ciba Foundation Symposium.1997; 205: 212-221.
3. Li RW. Adhesive solutions report of a case using multiple adhesive techniques in the management of enamel hypoplasia. Dent Update 1999; 26: 277-287.
4. Richard W, Monty S.D, Marien T.H. Pediatric Dentistry. 4th ed. United Kingdom: University Press; 2012.
5. Hall R. The prevalence of developmental defects of teeth enamel (DDE) in paediatric hospital department. Adv Dent Res. 1989; 3: 114-119.
6. Seow WK. A study of the developmental of the permanent dentition in very low birth weight children. Pediatric Dent.1996; 98: 379-384.
7. Baratieri LN, Araujo E, Monteiro S. Color in natural teeth and direct resin composite restorations essential aspects. Eur J Esthet Dent.2007; 2: 172-86.
8. Villarroel M, Fahl N, De Sousa AM, De Oliveira OB. Direct esthetic restorations based on translucency and opacity of composite resins. J Esthet Rest Dent.2011; 23: 73-87.
9. Azevedo DT, Almeida CG, Faraoni-Romano JJ, GeraldoMartins VR, Palma-Dibb RG. Restorative treatment on permanent teeth with enamel hypoplasia and crown dilacerations caused by trauma to their primary predecessors. Int J Dent. 2011; 10: 38-41.
10. Pontons-Melo JC, Furuse AY, Mondelli J. A direct composite resin stratification technique for restoration of the smile. Quintessence Int. 2011; 42: 205.

1. Associate Professor (Operative Dentistry) De Montmorency Collage of Dentistry, Lahore, Pakistan
2. Operative Dentistry, De Montmorency Collage of Dentistry, Lahore, Pakistan
3 & 4. Assistant Professor (Operative Dentistry) De Montmorency Collage of Dentistry, Lahore, Pakistan
Corresponding author: “Dr Muhammad Salman Rashid” < dr_salman74@hotmail.com >

Muhammad Badar Munir1               BDS, MCPS, FCPS
Muhammad Salman Rashid2          BDS
Sadaf Qadeer3                                       BDS, FCPS
Saira Yousuf Dar4                               BDS, FCPS                                   

Zaid A. Al Jeaidi 3         BDS, AEGD, SBARD                                     

INTRODUCTION

Modern dentalceramic is the esthetic material of choice and has contributed greatly to the increased demand on cosmetic indirect restorations. Adhesive cementation of glass-ceramic restorations with a composite resin of optimum physical properties can withstand higher masticatory forces and has demonstrated improved clinical performance1 . Bonding of indirect ceramic restorations to tooth structure involves the luting agent to interact with two different surfaces i.e. enamel/dentin and ceramic. As compared to other ceramics lithium disilicateceramics offer enhanced flexural strength and fracture toughness2 . Some investigators, due to improved mechanical properties, have also used LD ceramics for 3 unit bridges3,4. As conditioning of tooth surface is a standard protocol for adhesive bonding, similar is the importance of conditioning the ceramic bonding surface for predictable adhesion. Hydrofluoric acid, as a surface treatment has a long term proven track record of favorable clinical outcome5 . Similarly, for the formation of a durable chemical bond, silane application is recommended6,7. And many authors consider treatment of ceramic surface both with HF acid and silane as indispensable5,8-10. In a recent study by Canay et al., 11 spectroscopic analyses showed formation of crystalline precipitates on the etched ceramic surfaces in the form of Na, K, Ca & Al by-products. These by-products of HF acid etch are readily insoluble in water and possibly contaminate the ceramic bonding surface. In addition a cleaning regime for etched ceramic surfaces has been recommended12, which includes use of 37.5% Phosphoric acid for 1 min, rinse with water for 20 seconds and ultrasonic bath immersion. Therefore it is hypothesized that the presence of surface residue and crystalline salts after ceramic etching would compromise the bond between ceramic and resin.

In addition, effective removal of crystalline precipitates from etched ceramic surface would result in a durable and predictable ceramic resin bond. Therefore, this study aimed to evaluate the influence of post HF acid etch crystalline residue on bond integrity of LD by means of microtensile bond strength (μ-tbs) testing.

METHODOLOGY

The methodology of this study is similar to our previously published paper20. Briefly, 30 blocks of lithium disilicate ceramic (IvoclarVivadent) measuring 4x6x8 mm of were prepared, grit blasted with alumina (70µm glass beads, finished with 240-1200 grit SiC) and cleansed in ultrasonic bath for 10 minutes.

A total of 20 ceramic blocks were etched using 9.5% HF acid for 90 seconds and rinsed with water for 20 seconds (sec) for removal of HF acid. 10 ceramic blocks were left un-etched to be used as negative controls (Group A). All the experimental ceramic specimens were divided into the following three groups (A,B and C) depending on the surface treatments.
The prepared ceramic blocks were subjected to following surface treatment:

• Group A: LD ceramic blocks + no HF acid etch + Silane (S) application (5 minutes) Group B: LD ceramic blocks + HF acid etch + Rinse with water (20 secs) + Silane (S) application (5 minutes).
• Group C: LD ceramic blocks + HF acid etch + Rinse with water (20 secs) + Post etch cleaning (37.5% phosphoric acid (H3PO4)with agitation for 1 min, water rinse 20 sec and ultrasonic cleaning (US) for 5 min in distilled water bath) + Silane (S) application (5 minutes).

An adhesive (Optibond FL, Kerr) was applied to all the surface treated ceramic blocks. Composite blocks (Hybrid filler) (4x6x8 mm) of same dimensions as ceramic blocks were fabricated using a rubber (Aquasil, putty) copy mould of ceramic blocks. Composite and ceramic blocks were bonded using a 10 sec load application of 1 kilogram and light cured (LED) for 160 sec (650 mWcm-²). The bonded compositeceramic blocks were sectioned using slow speed diamond wheel saw (Isomet 1000) at a constant speed of 500 rpm at 250 g force. Specimen sticks of 1mm² cross section (non trimming technique) were produced and stored for 24 hours in normal saline. Hundred specimen for each group were randomly selected for microtensile testing. The specimens were attached to the tester jaws using cyanoacrylate adhesive and loaded to failure under tension at a crosshead speed of 0.5mm/min using a microtensile tester. The means of μ-tbs were analyzed with one way ANOVA. Details of the materials and equipment used in the study are presented as appendix A.

RESULTS

The data was normally distributed as revealed by Kolmogrov Smirnov test. The lowest and highest μ-tbs value was shown by group A (10.81±3.02) Mpa and group C (39.94±2.58) respectively. Table no. 1 represents mean µ-tbs values. The difference in the µtbs values between different groups is graphically presented in Fig. 1. Comparison using ANOVA revealed a statistically significant difference in the μ- tbs value among the three different groups (p=0.01). Post-etch cleaning of the residue formed on ceramic surface showed significant improvements in μ-tbs value (p=0.01) when compared to un-etched and etched ceramic specimens.

DISCUSSION

The application of glass ceramic based inlays, onlays and crowns are frequently employed in oral rehabilitation due to tooth conservation. And the ability of glass cermaics to form a durable adhesive bond to tooth structure is critical to its clinical success13,14. The present study was based on the hypothesis that formation of surface residue and crystalline salts due to HF acid etch can potentially interfere with the ceramic adhesive bond. In addition a standard post etch cleaning regime would result in improvement of glass ceramic bond strength to resin composite. Both these hypothesis were found to be acceptable as a result of the present study results.

Resin composite was used as the bonding substrate, instead of tooth structure. The explanation for this is twofold, primarily because the aim was to evaluate contribution of surface treatment steps of ceramics and secondarily, in order to minimize the likely variables in the experiment which includes, quantity and structure of exposed dentine, size and number of tubuli openings and tooth surface treatment15. Hydrofluoric acid etching of ceramics was used as it produces a consistent and favorable micro morphology of surface for micromechanical retention16. Etching further increases the surface free energy and reduces the surface contact angle, improving wettability for the luting agents17,18. Moreover, microtensile bond strength test was used as it represents the true adhesive bond strength19, 20. compared to shear bond test, which reflects the strength of base material21.

Previous analyses have revealed significant increase in the bond strengths of ceramic materials on silane application. Silanes being bifunctional molecules promote ceramic resin adhesion and facilitate resin penetration into the acid etched ceramic by enhancing the wetting of the surface. One of the previous report6 have identified silane as having a major effect on bonding of resin to lithium disilicate ceramics. In the present study silanes were included in the adhesive regime in all experimental groups to produce a durable bond and to simulate clinical protocol.

The present study showed that etching with HF acid followed by no standard post etch cleaning regime resulted in bond strength values significantly lower than specimens cleaned with post etch cleaning regime after etching. According to a study using energy dispersive spectroscopy, it was concluded that surface etching of glass ceramics leaves a layer of poorly adherent precipitates composed of reaction products of fluorosilicate of Na, K, Ca and Al.(11)In an earlier study, it was shown that failure to remove these precipitates, resulted in a 50% reduction in microtensile bond strength when bonding feldspathic ceramic to composite resin12. In the present study similar findings were observed with regards to lithium disilicate ceramics.

In the present study, post etch cleaning included application of phosphoric acid and ultrasonic bath immersion, significantly improving adhesive bond strength. However, it would be interesting to investigate the individual contribution of ultrasonic cleaning and phosphoric acid on the bond strength in order to simplify the bonding process clinically. Therefore further studies in this regard are warranted. A 90 seconds etch time was employed in the present study, however studies have reported bond strength values for lithium disilicate ceramics four times than other glass ceramics16 using a 2 minute ceramic etch time. Therefore further studies with varying etching concentrations and durations to improve the ceramic bonding regime are recommended.

CONCLUSIONS

Within the limitations of the study, the following conclusions can be drawn with respect to the materials used:

• The presence of surface residue and crystalline salts produced after ceramic etching significantly compromised the microtensile bond strength of LD ceramic to resin.
• Post etch cleaning of lithium disilicate ceramics significantly improved the their microtensile bond strength to resin.

DISCLOSURE

None declared.

REFERENCES

1. Bindl A, Lüthy H, Mörmann WH. Strength and fracture pattern of monolithic CAD/CAM -generated posterior crowns. Dent Mater 2006; 22:29-36.
2. Höland W, Schweiger M, Frank M, Rheinberger V. A Comparison of the microstructure and properties of the IPS Empress I and the IPS Empress II glass-ceramics. J Biomed Mater Res 2000; 53: 297-303.
3. Oh SC, Dong JK, Luthy H, Scharer P. Strength and microstructure of IPS Empress 2 glass-ceramic after different treatments. Int J Prosthodont 2000; 13:468-72.
4. Nakamura T, Ohyama T, Imanishi A, Nakamura T, Ishigaki S. Fracture resistance of pressable glass-ceramic fixed partial dentures. J Oral Rehab 2002; 29:951-5.
5. Ozcan M, Vallittu PK. Effect of surface conditioning methods on the bond strength of luting cement to ceramics. Dent Mater 2003; 19:725-31.
6. Alfredo MH, Luiz CCV, Alito A, Sylvio MJ. Effect of different ceramic surface treatments on resin microtensile bond strength. J Prothodont 2004; 13:28-35.
7. Blatz MB, Sadan A, Maltezos C, Blatz U, Mercante D, Burgess JO. In vitro durability of the resin bond to feldspathic ceramics. Am J Dent 2004; 17:169-72.
8. Chen JH, Matsumura H, Atsuta M. Effect of different etching periods on the bond strength of a composite resin to machinable porcelain. J Dent 1998; 28:53-58.
9. Kato H, Matsumura H, Ide T, Atsuta M. Improved bonding of adhesive resin to sintered porcelain with the combination of acid etching and a two-liquid silane conditioner. J Oral Rehab 2001; 28:102-108.
10. Brentel AS, Ozcan M, Valandro LF, Guimara L, Amaral R, Bottinoa MA . Microtensile bond strength of resin cement to feldspathic ceramic after different etching and silanization regimens in dry and aged conditions. Dent Mater 2007; 23:1323-1331.
11. Canay S, Hersek N, Ertan A. Effect of different acid treatments on a porcelain surface. J Oral Rehab 2001; 28:95-101.
12. Magne P, Cascione D. Influence of post-etching cleaning and connecting porcelain on the microtensile bond strength of composite resin to feldspathic porcelain. J Prosthet Dent 2006: 96: 354-361.
13. Bindl A, Mormann WH. Survival rate of mono-ceramic and ceramic-core CAD/ CAM-generated anterior crowns over 2-5 years. Eur J Oral Sci 2004; 112:197-204.
14. Attia A, Abdelaziz KM, Freitag S, Kern M. Fracture load of composite resin and feldspathic all-ceramic CAD/CAM crowns. J Prosthet Dent 2006;95:117-23.
15. Øilo G. Bond strength testing- what does it mean? Int Dent J 1993; 43:492- 498.
16. Della Bona A, Anusavice KJ, Mecholsky JJ Jr. Failure analysis of resin composite bonded to ceramic. Dent Mater 2003; 19:693-99.
17. Phoenix S, Shen C. Characterization of treated porcelain surfaces via dynamic contact angle analysis. Int J Prosthodont 1995; 8:187-94.
18. Addison O, Marquis PM, Fleming GJ. The impact of hydrofluoric acid surface treatments on the performance of a porcelain laminate restorative material. Dent Mater 2007; 23:461-68.
19. Van Noort R, Noroozi S, Howard IC, Cardew G. A critique of bond strength measurements. J Dent 1989; 17:61-67.
20. Della Bona A, van Noort R; Shear vs. tensile bond strength of resin composite bonded to ceramic. J Dent Res 1995; 74:1591-1596.

1. Conservative Dental Science Department, College of Dentistry, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia. Corresponding author: “Zaid A. Al Jeaidi” < ksacademics1@gmail.com >

Zaid A. Al Jeaidi 3         BDS, AEGD, SBARD                                     

Iqura Khan¹                      BDS
Raza Javed²                      BDS
Rizwan Mahmood³        BDS
Faiza Awa³                        BDS, MPhil
Ayyaz Ali Khan³              BDS, MSc, PhD

INTRODUCTION

The American Dental Association defines early childhood caries (ECC) “presence of black lesion (cavitated or non-cavitated) in any primary tooth of a preschooler, 0-71 months old.”1, 2 It is also known as ‘baby  bottle’ or ‘nursing bottle’ caries. Mostly, it occurs on labial surfaces of maxillary anterior teeth but any other tooth can be affected as well. It is an infectious, chronic disease caused by a number of factors which affects 1-17% children in developed and 70% children in under-developed countries.3 The triad for caries to occur includes tooth surface, cariogenic bacteria and fermentable carbohydrates.4 Several behavioral factors and demographics appear to be determinants of ECC which include limited access to care, finances and oral health education. In addition, the value that parents place on primary teeth and views on prolonged bottle-feeding have also been identified as predictors of caries-risk.2

It is the most prevalent unmet health need especially among children in the developing countries. Left untreated, ECC impacts the quality of life to an extent similar to other systemic diseases and may lead to excruciating dental pain and infection.5

Highest prevalence of early childhood caries is reported from Africa and South-East Asia.6 In India, prevalence of this disease among children between 8–48 months was reported as 44%.7. One study in Sri Lanka reported the incidence of ECC to be 23% in children of age 1-2 years.8 While in North America the prevalence of ECC ranges from 11-72%.9 In Pakistan difference studies stated the prevalence of ECC from 27.9% to 51%10 11.

A valuable tool can be prepared by knowing the frequency and prevalence of ECC and its contributing factors, which will help in planning and implementing health care programmes. Such data is rarely found especially when it comes to a developing country like Pakistan. Aimed at focusing 6-36 months old children, this study is meant to assess the frequency of ECC on the basis of various risk factors.

METHODOLOGY

This cross-sectional survey was conducted at Outpatient Department (OPD) of Pediatrics, Shaikh Zayed Medical Complex Lahore, for 06 months. A total of 400 children from 6-36 months of age with no physical or mental illness were included in the study. Verbal consent from parents was obtained prior to including children in the study and an interviewer administered questionnaire asked mother’s education, oral hygiene aids, feeding method and pattern and sugar consumption by the child. After explaining the aim of study, oral cavity of children and their mothers was examined under good light using disposable wooden spatulas. The deft and DMFT was calculated after examination. Data collection and examination was done by three dental surgeons to facilitate the process.

The completed questionnaires were collected and total responses for each item were tabulated. Data was entered and analyzed by using statistical software, Statistical Package for Social Sciences (SPSS) version 21.0. Chi square test was applied as test of significance. For all analysis p value ≤0.5 was taken as significant.

RESULTS

The prevalence of ECC in our study was 26.5% in all children of age 6-36 months with mean deft value of 0.60± 1.13 and mean DMFT value of 1.60±1.88 (see Table 1).

The comparative analysis showed that in age >12 months, the frequency of ECC was significantly high (P<0.05) (see Table 3), however there was no difference in both genders for ECC (P>0.05). While feeding method and pattern, sugar addition to bottle milk, dietary habits and mothers’ education (P>0.05) had significant impact on frequency of ECC (p<0.05) (see Table 2).

DISCUSSION

ECC is a major public health problem that continues to affect toddlers and small children worldwide with prevalence varying among populations. Many studies on ECC have been conducted to identify the etiology, prevalence, risk factors and treatment of this disease over the past 40 years12.

This study also adds to the evidence of existing knowledge. The study was conducted in the Outpatient Department of Pediatrics, Sheikh Zayed Medical Complex Lahore, among 400 children of age between 6-36 months. The study determined that almost one fourth, 26.5% of children had ECC. This shows a slight variation from a few previous studies done in Pakistan. In a study conducted at Tertiary Care Hospital, Karachi in 2010, the reported prevalence was 50.1% in children attending dental OPD.13 While a research by Sufia et al., calculated the dental caries prevalence about 40.1% among the children of 3-5 years.14 Both of these were community based holistic studies which would explain the difference in result from our study.

The present study reported that statistically significant (82.5%) children with ECC were either bottle fed or taking both. This is supported by a similar study conducted in the department of Child Dental Health at University Teaching Hospital Lagos, Nigeria which showed that children who were solely bottle-fed had a caries prevalence of 33% greater than those who were solely breastfed (15.7%) or taking both (25.3%)15.

It was also apparent in our study that in the age >12 months, the prevalence of ECC was significantly high (P<0.05), contrary to a study conducted in Karachi where age had no significant impact on ECC.16 However, other studies conducted in Peshawar10 and Sri Lanka17 showed higher frequency of dental caries with age.

Gender had no significant role in the development of ECC. These findings are in agreement with other studies conducted in Peshawar10 and Karachi.18.

In our study, mother’s education which appeared to be directly influencing the child’s dietary habits and oral hygiene aids was found to be indirectly proportional to the prevalence on ECC. This is supported by the analysis of another study conducted in India19 where the children of less educated and illiterate mothers had more dental caries.

CONCLUSION

Frequency of ECC in patients presenting to Pediatrics Department of Sheikh Zayed Medical Complex. Medical Complex was found to be 26.5%. Feeding habits and mother’s education was found to have a significant association with frequency of dental caries.

ACKNOWLEDGEMENT

Pediatrics Department of Shaikh Zayed Medical Complex. Miss Iqra Waheed, Consultant Biostatistician.

AUTHORS’ CONTRIBUTION

Dr. Iqura Khan Assisted in data collection and write up.
Dr. Raza Javed Assisted in data collection.
Dr. Rizwan Mahmood Assisted in data collection.
Dr. Faiza Awais Assisted in write up.

DISCLOSURE

NONE declared.

REFERENCES

1. Drury TF, Horowitz AM, Ismail AI, Maertens MP, Rozier RG, Selwitz RH. Diagnosing and reporting early childhood caries for research purposes: a report of a workshop sponsored by the National Institute of Dental and Craniofacial Research, the Health Resources and Services Administration, and the Health Care Financing Administration. J Pub Health Dent 1999; 59(3): 192-97.
2. Kumarihamy SL, Subasinghe LD, Jayasekara P, Kularatna SM, Palipana PD. The prevalence of Early Childhood Caries in 1-2 yrs olds in a semi-urban area of Sri Lanka. BMC Res Notes 2011; 4: 336.
3. Ghazal TSA. Prevalence, Incidence and Risk Factors for Early Childhood Caries Among Young African-American Children in Alabama. J Public Health Dent 2013; 75(1): 42-8.
4. van Loveren C, Broukal Z, Oganessian E. Functional foods/ingredients and dental caries. Eur J Nutr 2012; 51(2): 15-25.
5. Goettems ML, Ardenghi TM, Demarco FF, Romano AR, Torriani DD. Children’s use of dental services: influence of maternal dental anxiety, attendance pattern, and perception of children’s quality of life. Commun Dent Oral Epidemiol 2012; 40(5): 451-58.
6. Kumar VD. Early childhood caries – an insight. J Int Oral Health 2010; 2(1):1-9
7. Ribeiro NM, Ribeiro MA. Breastfeeding and early childhood caries: a critical review. J Pediatr 2004; 80(5): s199-s210.
8. Shahim FN. Factors of risk ealey childhood caries in a selected district in Sri Lanka. Colombo, Sri Lanka: University of Colombo; 2003.
9. Low W, Tan S, Schwartz S. The effect of severe caries on the quality of life in young children. Pediatr Dent 1998; 21(6): 325-26.
10. Saleem U, Bibi S, Jamil B. Early childhood caries and its relationship with different risk factors in preschool children. J Postgrad Med Inst 2015; 29(1):24-7.
11. Dawani N, Nisar N, Khan N, Syed S, Tanweer N. Prevalence and factors related to dental caries among pre-school children of Saddar town, Karachi, Pakistan: a cross-sectional study. BMC Oral Health 2012; 12(1):59.
12. Peretz B, Eidelman E. New insights into early childhood caries and strategies for prevention. In: Gluck GM, Morganstein WM, editors. Jong’s community dental health. Philadelphia: Mosby; 2003. p.157-59.
13. Inayat N, Mujeeb F, Shad MA, Rashid S, Hosein T. Early childhood caries, bottle-feeding, socioeconomic status, cariogenic snacks. J Pak Dent Assoc 2010; 19(1): 34-41.
14. Sufia S, Chaudhry S, Izhar F, Syed A, Mirza BA, Khan AA. Dental Caries Experience in Preschool Children—Is It Related to A Child’s Place of Residence and Family Income? Oral Health Prevent Dent. 2011; 9(4): 375-79.
15. Olatosi O, Sote E. Association of early childhood caries with breastfeeding and bottle feeding in southwestern Nigerian children of preschool age. J West Afr Coll Surg 2014; 4(1): 31-53.
16. Charani A, Mohsin S, Sufia S, Khan A. Prevalence of early childhood caries among 3-5-year old children of Clifton, Karachi. J of Pak Dent Assoc 2011; 20: 89-92.
17. Perera PJ, Abeyweera NT, Fernando MP, Warnakulasuriya TD, Ranathunga N. Prevalence of dental caries among a cohort of preschool children living in Gampaha district, Sri Lanka: A descriptive cross sectional study. BMC Oral Health 2012; 12(1):49.
18. Inayat N, Mujeeb F, Shad M, Rashid S, Hosein T. Experience of early childhood caries in children at Fatima Jinnah dental college and hospital, Karachi and its relationship with feeding practices. J Pak Dent Assoc 2010; 19: 35-40.
19. Prakash P, Subramaniam P, Durgesh B, Konde S. Prevalence of early childhood caries and associated risk factors in preschool children of urban Bangalore, India: A cross-sectional study. Eur J Dent 2012; 6(2): 141.
    

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1 & 2. Senior House Officer, Shaikh Zayed Medical Complex, Lahore, Pakistan
2. PG candidate for Oral Pathology, University Sains Malaysia, Kelantan, Malaysia.
3. Dental Surgeon, Ghurki Trust Teaching Hospital, Lahore, Pakistan.
4. Head of Department of Oral Health Sciences, Shaikh Zayed Medical Complex, Lahore, Pakistan.
Corresponding author: “Dr. Iqura Khan” < iqrat@live.com >

Iqura Khan¹                      BDS
Raza Javed²                      BDS
Rizwan Mahmood³        BDS
Faiza Awa³                        BDS, MPhil
Ayyaz Ali Khan³              BDS, MSc, PhD

Mohammad Mustafa¹    BDS, FCPS
Shahid Mahmood²         BDS, FCPS
Zaid A. Al Jeaidi³            BDS, MDSc

INTRODUCTION

Information on reasons for a treatment in a community is necessary to understand the disease pattern. This information is also useful to determine cost effectiveness of the treatments. In terms of root canal treatment (RCT),several studies have been conducted in developed countries concerning reasons for root canal treatment1-3. Some studies are available from developing countries as well4-8. However, only two studies have been reported from Saudi Arabia, and these too were reported from King Saud University, Riyadh.4,6In recent years, many new dental institutions have been launched in Saudi Arabia. Prince Sattam Bin AbdulAziz University (PSAU), Alkharj is one of the new institutions; only three batches have graduated so far. It is necessary that studies be conducted in new institutions to understand the disease pattern in different areas of Saudi Arabia, as well as the demands for treatments. These studies will help in planning of health facilities in future.

According to the prescribed dental curricula of Saudi Arabia, endodontic training must be provided to all dental students within five years. A preclinical course is started in the third year requiring students to perform root canals on extracted teeth. Clinical courses follow, with fourth year dental students undertaking education in endodontic treatment tailored to specific requirements. In the fifth year, students are required to complete endodontic procedures as part of a comprehensive dentistry course. In the internship period, students undertake routine root canal therapy as part of their duty.
As there is no study available on reasons for root canal treatment at PSAU; the present study was undertaken. The objective of the study was to carry out an analysis of root canal treatments done in the students’ clinics of the 4th year dentistry course to understand the reasons of root canal treatment at PSAU.

METHODOLOGY

Information on root canal treatments (RCT) was obtained through a specially designed form. Information regarding patient age, gender, tooth number, and reasons of the RCT or those of failures was required. The criteria for reasons for RCT were those derived from Saad and Clem, 3 as shown in Table 1.

The forms were distributed to the 4th year students of the PSAU attending during the academic year 2015-16. The participants were asked to register all root canal treatments carried out during a period of one academic year using their routine methods of diagnosis and treatment planning. The faculty was requested to examine the forms submitted by the students to verify the records. Data from the case records were collected and then coded for entry into a database using the Statistical Package for Social Sciences (SPSS), version 22. Frequencies were calculated using routine arithmetical methods.

RESULTS

Information was recorded on 202 RCTs. The majority (98%) of the patients were males while 2% were females. The average age of the patients was 36.9 years (±15.1).

The percentage distribution of reasons and the diagnosis of the pulpal conditions are given in Table 2 and 3 respectively. Irreversible pulpitis (59.9%) was the most common reason followed by necrosed pulp (22.8%). Exposure because of dental caries (67.3%) was the major reason for RCT. The other major reasons were intentional RCT for trauma (5.9 %) and overdentures (4%).

As shown in Table 4, most (54.5%) of the RCTs were carried out in maxillary teeth. The most frequently treated teeth were maxillary Ist and IInd premolars (7.4% each).

In pre-operative radiographs (Table 5), 62.9% had normal periapical area, while 22.8% showed evidence of widening of periodontal ligament and were diagnosed as with chronic apical periodontitis. Only 1 case (0.5%) was reported with internal resorption.

In pre-operative radiographs (Table 5), 62.9% had normal periapical area, while 22.8% showed evidence of widening of periodontal ligament and were diagnosed as with chronic apical periodontitis. Only 1 case (0.5%) was reported with internal resorption.

DISCUSSION

The study has provided a useful information for root canal treatment pattern in the undergraduate clinical program at PSAU. It is hoped that more representative studies would be undertaken in Saudi Arabian the future, which will help in future planning for dental care.
In terms of the gender of the patients, the number of male patients exceeded the number of female patients. In some previous studies,1,3 the percentage of female patients was higher. PSAU campus caters for male dental students, and therefore is mainly meant for the male patients. Our results matched with a previous study in another Saudi University, where the number of male patients was also higher.6 It is also important to understand the social setup of Saudi Arabia, where female patients prefer to be treated by the female dentists.

Irreversible pulpitis and necrotic pulp were the most common causes for seeking root canal treatment by the patients. These results are in agreement with the previous studies conducted in Saudi Arabia and elsewhere.1,3,4,6-8. However in our study, compared to a previous study in Saudi Arabia,6 the necrotic pulp was outnumbered by irreversible pulpitis. It may be explained from the fact that the previous study was carried out at King Saud University, where there is a long waiting list. On the other hand, the patients at PSAU, it being a new campus with a lesser patient load, had an immediate access to endodontic clinics. Nevertheless, pulpitis and necrosis of pulp could be considered as is a natural sequelae of untreated dental caries. It is supported by the fact that 67.3% of the patients had carious exposure in this study. This fact is also evident from various epidemiological studies, which have shown that caries is a major dental problem in Saudi Arabia.9-11

Similar to the studies reported earlier,1-3, 6 trauma was a less likely cause for root canal treatments. In addition to the fact that the patients treated in this study were not treated as emergencies, the average age of the patients was 36.9 years, and it has been shown previously that trauma is less likely to occur in this age group.3

The frequency of intentional root canal for the purpose of over-dentures was only 4%. It is understandable as every effort is made to maintain healthy teeth, even in the provision of overdentures. Our results are similar to the previous studies. 3,6

Very few cases were reported for failure of root canal treatments; it was mainly because of short-obturations, when compared with over obturations. It may be argued that in overobturation, the canals are cleaned completely and that extruding material provides good apical seal and is well tolerated by periapical tissues.11Our sample of failed treatments was so small, so a generalized statement about RCT in Saudi Arabia could not be made. Further investigation is required in this regard.

One interesting feature of pre-operative radiographs worthnoting was absence of peripaical radiolucency in most cases despite carious exposure of the pulp. This presents a diagnostic dilemma. Therefore, the clinical and radiographic examinations may give conflicting results and definitive pulp and periapical diagnosis must be made with great care. Endodontic treatments are likely to take a significant share of the workload of dentistry in Saudi Arabia, in future.

Therefore, prevention and an early treatment of carious lesions is essential to reduce the need for root canal treatments.

CONCLUSIONS

1. Necrotic pulp and irreversible pulpitis were the predominant reasons for root canal treatment in this study.
2. Most of the cases for necrotic pulp and irreversible pulpitis occurred because of carious exposure.

DISCLOSURE

None declared.

REFERENCES

1. Serene TP, Spolsky VW. Frequency of endodontic therapy in a dental school setting. J Endodon.1981; 7: 385-87.
2. Cyr G, Arvis L, Safavi K, Langeland K. Major etiologic factors leading to root canal procedures. J Endodon. (abstract No. 31) 1985; 11-145.
3. SaadAY, Clem WH. An evaluation of etiologic factors in382 .patients treated in a postgraduate endodontic program. Oral Surg. 1988; 65: 91-3.
4. Al-Yahya AS , SelimHA. The etiology and symptoms of endodontic cases treated in a university clinic in Saudi Arabia. Saudi Dent J.1990; 3: 86-90.
5. Al-Negrish AR. Incidence and distribution of root canal treatment in the dentition among a Jordanian sub population. Int Dent J. 2002; 52: 125-29.
6. Mahmood S, Al-Yahya A, Saad AH,Aha Hussain K.Reasons for root canal treatment in students’ and interns’ clinics in college of dentistry, King Saud University, Saudi Arabia.J Pak Dent Assoc. 2003; 12: 33-36
7. Lal U, Abidi SYA, Rashid S. Reasons for root canal treatment in the department of endodontics of Fatima Jinnah Dental College hospital, Karachi. Pak Oral Dent J. 23; 2003; 151-52
8. Faisal D, Shah S, Kumar N, Ali SA, Nadia N. Root canal treatment; frequency in department of endodonticin dental colleges of Karachi. Professional Med. 2012; 19: 739-741.
9. Al-Kateeb TL, Al-Marsafi A, O’Mullane DM. Caries prevalence and treatment need amongst children in an Arabian community. Community Dent Oral Epidemiol.1991; 19: 277-80.
10. Al-Mohammadi SM, Rugg-Gunn AJ, Butler TJ. Caries prevalence in boys aged, 2, 4, and 6 years· according to socio economic status in Riyadh, Saudi Arabia. Community Dent Oral Epidemiol. 1997; 25: 184-86
11. Wyne A, Darwish S, Adenubi J, Battata S, Khan N. The prevalence and pattern of nursing caries in Saudi preschool children. Int J Pediatr Dent. 201; 11: 361-64.

1. Assistant Professor & Head of Endodontic Division, Prince Sattam Bin AbdulAziz University, Alkharj, Saudi Arabia
2. Professor of Restorative Dentistry, Department of Preventive Dental Sciences, Prince Sattam Bin AbdulAziz University, Alkharj, Saudi Arabia
3. Assistant Professor& Chairman, Department of Conservative Dental Sciences, Prince Sattam Bin AbdulAziz University, Alkharj, Saudi Arabia
Corresponding author: “Dr. Shahid Mahmood” < arslan9@hotmail.com >

Mohammad Mustafa¹    BDS, FCPS
Shahid Mahmood²         BDS, FCPS
Zaid A. Al Jeaidi³            BDS, MDSc

Bharat Kumar1     BDS, FCPS
Asma Naz2              BDS, FCPS
Haroon Rashid3   BDS, MDSc
Aamir Mahmood Butt4   BDS, FCPS

INTRODUCTION

Although, a large number of people have started to retain their teeth in the old age but still a considerable proportion of patient’s need complete dentures for their missing dentition1,2. Treating edentulous patients is a demanding task. Complete denture prosthesis is mainly retained by the physical forces. The retention is primarily achieved by a valve-like seal between the border of denture and the underlying mucosa which prevents trapping of air and liquids beneath the denture3 . This kind of seal is difficult to achieve along the posterior border of maxillary denture prosthesis4 .

In maxillary dentures, there is a need for extension of the posterior border so that adequate posterior palatal seal could be produced5,6. The location of the posterior border of the maxillary denture plays a very important role in denture’s retention, stability, support and patient’s comfort7 and the determination of this area remains a critical step during the complete denture fabrication8 .

Many studies have described the techniques of locating the posterior border of the maxillary complete denture and majority of the studies mention the displacement of soft tissues as the critical factor in the posterior palatal seal determination9,10. Only a few have discussed the neurophysiologic and psychological considerations of extending the posterior border of maxillary denture9,10. Some anatomical structures serve as reliable guidelines for the location of the posterior border of the maxillary denture. These guides are the fovea palatini which are clinically visible pits indentations close to the mid line of palate formed by coalescence of several mucous gland ducts and are usually located close to vibrating line within the soft tissues2.
There is a general agreement that the posterior extent of the maxillary denture should extend at least to the vibrating line or the borders should terminate at the vibrating line10. The vibrating line is an imaginary line that is drawn across the palate and marks the beginning of the movement in the soft palate when the individual say “ah”2. Extending from one hamular notch to the other, the line usually passes about 2 mm in front of the fovea palatini2. It is physiologically present at the junction of the moveable and immovable portion of the soft palate10 and its location is largely dependent upon visual observation11. The techniques for the determination of its location are based on the phonation of “ah” sound that causes the soft palate to lift2,11,12,13,14, T burnisher palpatory method11,15, swallowing method11,16,17 and nose-blowing or valsalva maneuver10,11,14,17,18.
The location of vibrating line varies with the location of the contour of the soft palate19. The soft palate is the movable part of the palatal anatomy posterior to the hard palate20 and its movement and degree of displace-ability varies in individuals 6. Millsaps21 proposed three classes of palatal throat forms depending upon the angle formed between hard and soft palate. In class I, soft palate is horizontal or turns downward around 10 degree angle to the hard palate at mid palatal raphe, in class II, soft palate turns downward around 45 degree angle to the hard palate at midline, while in class III, soft palate turns downward around 70 degree angle to the hard palate respectively (Fig. 1).

The location of vibrating line relies on visual observation11 and varies with the contours of the soft palate [19]. A flat palatal vault in class I soft palate is associated with a relatively straight vibrating line. A medium depth palatal vault of class II soft palate is associated with a slightly curved vibrating line towards the incisive papillae making a bow shape, while a high “V” shaped palatal vault in class III soft palate is associated with the vibrating line being acutely curved towards the incisive papillae making a broad “M” 22.

Educational survey conducted by Rashedi and Petropoulos23 suggested that a large percentage of teaching hospitals used the one vibrating line concept for establishing the posterior palatal seal. However; Silverman9 stated that the posterior palatal seal of maxillary denture could be extended to an average distance of about 8.2 mm dorsally to the vibrating line to aid retention and stability of the denture.
Fig. (1). Soft palate type (A) Class I, (B) class II, (C) Class III.The rationale of this study is to determine the normal physiological location of vibrating line and fovea palatini in class I, class II and class III soft palate types. This study will contribute towards useful information that will be helpful for general dental practitioners and specialists in placing the posterior extent of the maxillary complete denture prosthesis.

METHODOLOGY

Sample size calculation for the cross-sectional study was performed using open epi website, using the data collected from a study conducted by Jongkittinarukorn24. Consecutive sampling was done and the duration of study was six months. The patients meeting the inclusion criteria such as both gender (male and female), age range from 20 to 60 years, having normal pink color palatal mucosa with clinically visible fovea palatine in all soft palate types were selected and those patients with history of craniofacial trauma or surgery, congenital and acquired craniofacial anomalies, any inflammation or pathology of palatal mucosa and limited opening of mouth were excluded from the study.

The patients meeting the inclusion criteria were selected and the informed consent was taken verbally and written in Urdu and English language from each patient regarding their willingness and participation in the study and the selected patients were divided into four groups, after collection of data according to their age:

• Group A: 20 – 30 years
• Group B: 31 – 40 years
• Group C: 41 – 50 years
• Group D: 51 – 60 years

The selected patients were seated on dental unit in an upright position with head held erect and asked to open the mouth wide, the palate of each patient was examined for the visibility of fovea palatini and soft palatal type (Class I, Class II and Class III) was observed by visual inspection and the findings were recorded in proforma.

After that the selected patients were instructed to pronounce “ah” sound in short bursts in a normal unexaggerated fashion repetitively to rehearse the “Ah” method until they became familiar with it. Mucosa of palate was dried using 2 X 2 cm gauze, as the soft palate moved up when the patients attempted to pronounce the “ah” sound, both the fovea palatini and the vibrating line were marked using an indelible pencil and the procedure was repeated twice to verify the accuracy of markings. The findings for the vibrating line were recorded in proforma as to whether it existed anteriorly, posteriorly or at the fovea palatine.

RESULTS

The results were analyzed using SPSS Version 16.0. The mean age of subjects were calculated. Frequency and percentage was calculated for genders and the various locations of vibrating line with respect to fovea palatini in class I, class II and class III soft palatal types. Stratification was done with regard to age and gender with respect to various locations of vibrating lines. The chi-square was done to observe the significant difference. Out of the total number of 197 patients (n=197), 58.4% were males and 41.6% were females. The mean age of the patients was found to be 40.11 (12.039) years. Group A consisted of 25.9% (n=51) patients while group B had a total of 25.4% (n=50) patients. Group C had the highest number of patients n=52 (26.4%) and the lowest number was recorded ingroup D, n=44 (22.3%). Out of this total number, 130 (66%) patients had vibrating line located anterior to fovea palatini while 67 patients (34%) had vibrating line located at the fovea palatini None of patients had the vibrating line located posterior to the fovea palatini. Regarding the frequencies of palate types, soft palate class I type was 94 (47.7%), class II was73 (37.1%), and class III was found to be 30 (15.2%). The vibrating line was found to be anteriorly present in 64 patients (68.1%) of soft palate class I type while in soft palate class II type, the number was 51(69.9%). None of soft palate classification showed location of vibrating line posterior to fovea palatini (Table 1). Chi-Square test was used to analyze the relation between gender and age groups with respect to various locations of vibrating line for stratification. There was no statistically significant difference seen (Table 2 and 3).

DISCUSSION

Despite the advances in implant dentistry, the fabrication of complete denture still remains the common prescription. Therefore, meticulous procedures have to be followed to ensure the success of complete denture25-27. A successful complete denture treatment should meet patient’s functional needs and gain their acceptance and well retained prosthesis must be provided 28-30. The currently used multiple techniques for location of the vibrating line. These include phonation of the “ah” sound, palpatory method, swallowing method and the nose-blowing or valsalva maneuver2,11,14,15,17,18. The “ah” method for location of vibrating line is used in the present study is a convenient method and mostly taught in US and Canadian dental schools and also in dental institutions of Pakistan23,31,33.

Lye32 carried out a study on 100 subjects and concluded that 92 of patients showed the presence of fovea palatini. The result of his study showed the vibrating line was anterior to the foveae palatini in 12 subjects (13.04 %). The foveae palatini and vibrating line coincided in 16 patients (17.39 %). The vibrating line was posterior to the foveae palatini in 64 subjects. Chen10 in Ohio checked the reliability of the fovea palatini in determining the posterior border of the maxillary denture. Out of a total number of 104 subjects in his study, 72 had fovea palatini visible clinically. He also stated that the nose-blowing method appears to be an accurate method for locating the fovea palatini and the vibrating line. Among 72 of his selected subjects, 25% had their vibrating line present on the fovea palatine and 75% had their vibrating line located anterior to the fovea palatini and none of the subjects had the vibrating line present posterior to the fovea palatini. These findings are similar to the results of the current study.

A study was conducted by Alousi7 which included 200 patients selected randomly without inclusion of soft palate types. The result of his study showed that 50.9% of patients had their vibrating line located at fovea palatini, 44.5% had it in front and 6.4% posterior to the fovea palatini. He concluded that fovea palatini is a reliable anatomical landmark that helps in determining post dam area of denture because and that there was no significant difference between gender and location of vibrating line in relation to fovea palatini. This finding of his study is similar to the finding of our study.

CONCLUSIONS

The vibrating line was predominately found anterior to the fovea palatine in subjects with Class I and II soft palate. Almost half of the subjects with deep soft palate (Class III type palate) had their vibrating line present on the fovea palatini. However, none of patients had their vibrating line location posterior to the fovea palatine in class I, II and III soft palate.

DISCLOSURE

NONE declared.

REFERENCES

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26. Vohra FA, Rashid H. Implant retained overdenture as first choice of care for edentulous mandibles: a presentation of two cases. J Pak Dent Assoc 2012; 21: 182-187.
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1. Department of Prosthodontics, Ziauddin College of Dentistry, Karachi, Pakistan.
2. Department of Prosthodontics, Jinnah Medical and Dental College, Karachi, Pakistan.
3. Department of Prosthodontics, Ziauddin College of Dentistry, Karachi, Pakistan.
4. Department of Prosthodontics, Liaqat University of Medical & Health Sciences, Jamshoro, Pakistan. Corresponding Author: “Dr. Haroon Rashid” < drh.rashid@hotmail.com>

Bharat Kumar1     BDS, FCPS
Asma Naz2              BDS, FCPS
Haroon Rashid3   BDS, MDSc
Aamir Mahmood Butt4   BDS, FCPS