Vol. 24 No. 04 Oct-Dec 2015

Rizwan Nadim¹                              BDS, MPH

Hasan Baber²                                 BDS,MSc, Pgdip

Kashif Aslam³                                BDS, MSc

INTRODUCTION

Halitosis is referred to as unpleasant odour in expired air. Halitosis may have physiological or pathological causes, the main cause is related to conditions in the oral cavity¹.The term is synonymous to foul breath, breath odour, and offensive breath as a result of reasons that consist but not limited to diseases of PDL, coating of tongue with bacteria, various systemic disorders and various type of foods¹.

Bad breadth has a long history which almost goes 4000 years back. Oral malodour originates in the mouth in 8090% of cases². Prevalence of halitosis has been studied, among individuals, in different parts of the world by convenience sampling. Research has indicated that chronic halitosis affects approximately one third of the group, while on the other hand severe halitosis may involve less than 5% of the population².

There is very limited data which is available in the literature that is concerned with prevalence of halitosis in wide-sample population. Most of the time these studies make use of subjective criteria from questionnaires in estimating the percentage of effected people in the population. A research that undertook in Sweden came to the conclusion that plaque and calculus were major contributing factors in severe halitosis³. Another study in Japan found direct correlation of periodontitis and coating of tongue to scores of volatile sulphur compounds⁴. This report further concluded high halitosis scores in patients with severe periodontitis then those without any active periodontal disease. Many studies have shown conclusive evidence that majority of the causes of bad breath originate from mouth^5,6. Periodontal and gingival diseases are responsible for around 60% of oral related factors and tongue was responsible for 40% of them. Thus halitosis has become one of common complaint for which a patient seeks treatment⁷.

The aim of this study was to find out the association of halitosis in different age groups with respect to oral hygiene maintenance/ oral conditions, habits, systematic problems and self-perception.

METHODOLOGY

A cross sectional study was done by using convenience sampling technique of four hundred fifty participants. The study was conducted in Dow Dental OPD during the month of July 2015. All participants above the age of twelve were included in the study. All participants excluded from the study were below the age of twelve, had mental problems or any physical disability. Data collection was done by self-reported questionnaire, visual examination with mouth mirror and palm test for oral conditions/oral hygiene maintenance, habits, systemic conditions and selfperception. The questionnaire was made by reviewing the literature (Almas et al⁸) and modifications were done according to local culture. In palm test participants were asked to put their right hand in front of the mouth and exhale to breathe out. Data analysis was done using SPSS 20.0. Chi square test was used to detect statistically significant association of halitosis of different age groups with oral conditions/oral hygiene maintenance, habits, medical/systematic conditions and self-perception. Permission for the study was taken from Dean of Dentistry of Dow University of Health Sciences and personal consent was also taken from participants.

RESULTS

Two hundred twenty seven of the participants were males (50.4%) and two hundred twenty three (40.6%) were females, the male female ratio 1:1 and the mean age 34.38+13.368. Individuals of different age groups were assessed for halitosis with respect to different factors evaluated in oral conditions/oral hygiene maintenance, habits, systemic conditions and self-perception. Factors which showed statistically significant values were dry mouth, tongue coated with white/yellowish deposits and flossing (Table 1), mouth breathers and those who consumed raw onions/garlic daily (Table 2), gastrointestinal problems (Table 3) and palm test. (Table 4).

Table 1: Association between oral conditions/hygiene in halitosis and different age groups

Table 2: Association between haboits in halitosis and different age groups

Table 3: Association  between medical problems in halitosis and different age groups

Table 4: Association  between self perception of halitosis and different age groups

DISCUSSION

Our study has demonstrated association of halitosis among individuals of different age groups with different factors. Most of our results have shown confinement with previous studies on halitosis and some new observations.

A strong association ( p<0.00 ) was observed, among respondants who had problem of mouth breathing and had halitosis. Out of 57% reporting bad breath and halitosis, 30% were adults aged 50 and above.Contrary to our findings Kara et al⁹ in his study on halitosis and its association with mouth breathing observed among total respondents having mouth breathing and halitosis, almost 70% were children aged 14-16 years old. A similar study was also done by Motta et al⁴ who found 75% of total respondents having oral malodour and breathing via mouth to be children age 12-14 years.

The possible explanation can be as mouth remains open majority of times, reduction in salivary flow/buffering capacity of saliva and water evaporating in saliva among mouth breathers might be a contributing factor to halitosis. As we grow old, we acquire various diseases and weak immune system.Thus older people often have systemic problems and diseases including sinus issues, congestion that force them to breath from their mouth and thus have problem maintaining their oral hygiene resulting in halitosis.

Among different oral conditions  statistically significant  (P<0.05) was observed among 29% of respondants who had xerostomia accompanied by halitosis. A linear trend was observed with incidence of xerostomia decreasing, with progression of age. From 33% in individuals aged 11-30 years old to 6% in 30-40 years old, decreasing to just 3% in elderly respondants.

Among various other oral hygiene conditions 49% of the respondnts had halitosis followed by coating of their tongue with yelowish white depositsts. Highest number was 30% observed in respondants age between 40-50 years old. Sterer et al¹⁰ in their study on oral malodour and halitosis observed 124 of their subjects age 23-24 years to have tongue scrapings associated with halitosis.

Similar studies by Miyazaki et al¹¹ ,Yaegaki.k et al¹² and Bosy et al⁵ have shown direct correlation of amount of tongue coatings with halitosis. Chaehoon Lee et al⁷ in his research on halitosis concluded that volatile sulphide compounds produced by tongue coatings played a major role in severity of oral malodour. He further suggested species found on dorsum of tongue included

Atopiumporulum, E.sulci and Fusobacterium. In individuals with oral malodour, tongue coating samples have been shown to hydrolyze N-benzoyl-Dl-Arginine-2maphthylamide “BANA”. Since “BANA” test detects arginine hydrolase produced by proteolytic bacteria. This test confirms presence of bacterial flora on dorsum of tongue with coatings in individuals with oral malodour.

When asked about habits 77% respondants agreed (P<0.05) to have halitosis and consuming tea and coffee. Highest number of 28%-30% of respondant were between age 11-30 years old. Although various researches like from X.xuy et al¹³ and Lodhia et al¹⁴ suggested catechins in tea extracts acting as natural suppressors of oral malodour. Milk in tea can aggravate halitosis. A report by Joe Graedon in Chron magazine suggested that patient having lactose intolerance have symptoms of oral malodour accompanied by other symptoms after consuming milk tea. Coffee is worse than usual because of its sulphurous content, which certain bad breath-causing bacteria can break down to produce odour. One final reason that drinking coffee can give you bad breath is simply that coffee has a very strong odour that smells worse than it tastes. Combined with the other bad-smelling odours, this can result in terrible smelling breath.

When respondants were asked regarding medical problems, 29% replied to have oral malodour as result of Gastro-Intestinal (GI) problems. Among them 29.5% (29-30 years and 50+yrs old) had the most complaint. Likewise Moshkowitz et al¹⁵ studied an association between halitosis and GERD (Gastro eosophageal reflux disease) in 132 participants and found 55% of them to be between the age of 20-87 years old. Diseases of GI system results in presence of odorous gases in the air expelled from the oral cavity and mouth. Scully et al¹⁶ suggested GERD extra-esophageal manifestation of gastro esophageal reflux disease as possible cause of halithosis. He further suggested that GERD might be a possible predisposing factor which act as breeding ground for bacteria in the oropharynx. Irwin et el¹⁷ suggested several mechanisms via which GERD may be contributing to halitosis. One is direct damage to oropharyngeal mucosa by gastroesophageal refluxate, that eject out into upper oesophageal sphincter and into oral cavity. Mamede de et al¹⁸ demonstrated that prevalence of severe hypertrophy of lymphoid follicles at base of tongue greatly increases in patients with GERD. Schroedor et al¹⁹, suggested halitosis as a result of dental erosion, which is a common complication of GERD.

Among other factors  in habits 35% of respondant consumed raw Onion/Garlic. Among these 159 participants, 33% were between age 20-30 years old. This suggests that halitosis induced due to raw onion and garlic is frequently seen in younger population. According to Lee et al⁷ both onion and garlic also contain high concentrations of sulphur, which can pass through the lining of intestine into the bloodstream, and subsequently be released into the lungs and then exhaled. Xiao-Jia et al⁶ so found direct correlation of garlic/onion with halitosis. He suggested ingestion of garlic (Allium Satium) is well known to cause bad breath. He suggested garlic breath odour comes from lungs not from particles retained in the mouth. He identified selenoamino acids found in garlic. He suggested that these compounds are the source of exhaled Se compounds found in garlic breath. He said Se compounds in garlic breath originate from hydrolysis of initially formed thiosulphanides such as allicin,in GIT, affording odorous compounds which then absorbed in the blood and exchange exhaled gases in the lungs.

We also observed correlation between halitosis and use of dental floss daily. The findings can be suggestive due to the fact that flossing daily have a masking effect, without really eliminating the real cause. Lastly correlation was also found in individuals whose social life was effected as a result of halitosis. In the past many researches have demonstrated effects of halitosis on social life. According to Hine Mk et al²⁰, halitosis can be considered as a social impediment. Sanz Mketel et al²¹ in his studies on halitosis suggested it to be an essential factor in social relationship and concerns not only with health aspects but also psychological changes which often leads to personal and social isolation. Individuals who self perceived halitosis, it was observed 21.5% had their social life affected as a result of it.With 32-40% from 97 being between age of 20-40 years old. This can be explained as younger population often socialize more then older people and so have more chances  to perceive negative impact of halitosis when socializing.

Interestingly, Al-Ansari et al²² assessed the prevalence and factors associated with self-reported halitosis in 1,551 Kuwaiti patients. The prevalence of self-reported halitosis was 23.3% which was contraindicatory to our result, as accessed by Palm Test which was 70%.

Self perception of halitosis have been widely studied in previous question-based study.In France out of 4817 subjects, 22% reported halitosis. In Japan among 2762 subjects 23% had diagnosed halitosis.A report by American Dental Association suggested 50% to have percieved oral Malodour. Limitation of the study is that data was collected from one site and and palm test is not an accurate diagnostic test when compared to Halimeter or Oralchroma.

CONCLUSION

Halitosis by itself produces symptoms that can itself cause social anxiety and problem in personal interactions. The study demonstrated younger participants, ranging from age 15 to 25 and those acquiring less level of education been more prone to self-perceived halitosis with presence of other underlying associated factors. Halitosis therefore requires not only the professional care provided by dentists, but also psychological support. The study recommends further investigations using the standard clinical methods available to assess the bad breath problem.

Authors Contribution:

RN conceived the idea, designed the objective (research question), did data collection and contributed to writing results. HB wrote the discussion and KA contributed to abstract, introduction and proof reading. Disclosure: No conflict of interest reported.

REFERENCES

1. Van den Broek A, Feenstra L, De Baat C. A review of the current literature on management of halitosis. Oral Dis. 2008;14(1):30-9.
2. Rosing CK, Loesche W. Halitosis: an overview of epidemiology, etiology and clinical management. Braz Oral Res. 2011;25(5):466-71.
3. Söder B, Johansson B, Söder P. The relation between foetor ex ore, oral hygiene and periodontal disease. Swed Dent J. 1999;24(3):73-82.
4. Motta LJ, Bachiega JC, Guedes CC, Laranja LT, Bussadori SK. Association between halitosis and mouth breathing in children. Clinics. 2011;66(6):939-42.
5. Bosy A, Kulkarni GV, Rosenberg M, McCulloch CA. Relationship of oral malodor to periodontitis: evidence of independence in discrete subpopulations. J Periodontol. 1994;65(1):37-46.
6. Cai X-J, Block E, Uden PC, Zhang X, Quimby BD, Sullivan JJ. Allium Chemistry: Identification of Selenoamino Acids in Ordinary and Selenium-Enriched Garlic, Onion, and Broccoli Using Gas Chromatography with Atomic Emission Detection. J Agric Food Chem.1995;43(7):1754-7.
7. Lee CH, Kho HS, Chung SC, Lee SW, Kim YK. The relationship between volatile sulfur compounds and major halitosis-inducing factors. J Periodontol. 2003;74(1):327.
8. Almas K, Al-Hawish A, Al-Khamis W. Oral hygiene practices, smoking habit, and self-perceived oral malodor among dental students. J Contemp Dent Pract. 2003;4(4):77-9
9. Kara C, Tezel A, Orbak R. Effect of oral hygiene instruction and scaling on oral malodour in a population of Turkish children with gingival inflammation. Int J Paediat Dent. 2006;16(6):399-404.
10. Sterer N, Greenstein RB, Rosenberg MB. Betagalactosidase activity in saliva is associated with oral malodour. J Dent Research. 2002; 81(3):182-5
11. Miyazaki H, Sakao S, Katoh Y, Takehara T. Correlation between volatile sulphur compounds and certain oral health measurements in the general population. J Periodontol. 1995;66(8):679-84.
12. Yaegaki K, Sanada K. Biochemical and clinical factors influencing oral malodor in periodontal patients. J Periodontol. 1992;63(9):783-9.
13. Lodhia P, Yaegaki K, Khakbaznejad A, Imai T, Sato T, Tanaka T, et al. Effect of green tea on volatile sulfur compounds in mouth air. J Nutr Sci Vitaminol. 2008;54(1):89-94.
14. XuY W. HeJ, et a1. Prevalenceand control of diabetes in chinese adults.JAMA. 2013; 310(9):948-59
15. Scully C, Greenman J. Halitosis (breath odor). Periodontology 2000. 2008;48(1):66-75.
16. Moshkowitz M, Horowitz N, Leshno M, Halpern Z. Halitosis and gastroesophageal reflux disease: a possible association. Oral Dis. 2007;13(6):581-5.
17. Irwin RS, French CL, Curley FJ, Zawacki JK, Bennett FM. Chronic cough due to gastroesophageal reflux. Clinical, diagnostic, and pathogenetic aspects. Chest J. 1993;104(5):1511-7.
18. Mamede RCM, De Mello-Filho FV, celso Vigário L, Dantas RO. Effect of gastroesophageal reflux on hypertrophy of the base of the tongue. Otolaryngol Head and Neck Surg. 2000;122(4):607-10.
19. Schroeder PL, Filler SJ, Ramirez B, Lazarchik DA, Vaezi MF, Richter JE. Dental erosion and acid reflux disease. Ann Int Med. 1995;122(11):809-15.
20. Hine MK. Halitosis. J Amer Dent Assoc (1939). 1957;55(1):37-46.
21. Sanz M, Roldan S, Herrera D. Fundamentals of breath malodour. J Contemp Dent Pract. 2001;2(4):1-17.
22. Al-Ansari JM, Boodai H, Al-Sumait N, Al-Khabbaz AK, Al-Shammari KF, Salako N. Factors associated with self-reported halitosis in Kuwaiti patients. J Dent. 2006;34(7):444-9.

1. Assistant Professor, Department of Community Dentistry Dow Dental College , Dow University of Health Sciences.
2. Assistant Professor, Department of Oral Biology, Dow Dental College, Dow University of Health Sciences.
3. Assistant Professor, Department of Prosthodontics, Dow Dental College, Dow University of Health Sciences.

Corresponding author: “Dr. Rizwan Nadim ” < rizwaan_21@hotmail.com >

Saad Asad¹                                     BDS, FCPS

Mahrukh Tanveer²                      BDS

Amna Asif³                                        BDS

INTRODUCTION

One of the major cause of death throughout the world remains the cancer^1,2.Carcinogenesis is a multifactorial phenomenon with a complex interplay between genetics and environmental factors; mainly related to healthy habits and lifestyle^2,4. Cancer may also be caused by oxidative stress in addition to these factors^5,6.In the recent past though exponential progress in the prevention and management of cancers have taken place but as mentioned already its incidence is increasing at an alarming rate day by day due to the reasons already mentioned^7,8. However, over a quarter of the incidence may be preventable by just adjusting the diet⁷. Diet in the recent past has been given too much importance because of its anti-oxidant and anti-cancer effects. “Let food be thy medicine and medicine be thy food”, as said by the father of medicine, Hippocrates in 431 B.C. Nature has provided us with a variety of treatment modalities in the form of fruits and vegetables⁹. Many of them consist of ingredients with hidden pharmaceutical qualities ranging from anti-inflammatory to anti-carcinogenic agent. They not only boost our innate immunity but also act as an adjunct to medicines for specific treatment⁹.

In a review of 200 papers on anti-cancer effect of vegetables Block et. al. reported that a significant proportion of studies found a positive relationship¹⁰. In another review of 206 studies, the similar relationship was examined and it was found that cruciform vegetable reduces chances of cancer occurrence¹¹. Amjad Al et al in their study found an anti oxidant to anti-cancer effect of Sulforaphane (SFN) a metabolic by product of cruciferous vegetables¹². Awasthi S, Saraswathi NT in found a potent anticancer effect of glucosinolate found in cruciferous vegetables¹³. Ahmadi A, Shadboorestan A in their study found that flavonoids one of the most important ingredients in vegetables and fruits exhibits an anti-cancer effect¹⁴. Michaud DS et al in their study found that 20% increase in vegetable intake generally corresponds to a 20% decrease in cancer rates, and a 20% increase in cruciferous vegetable intake corresponds to a 40% decrease in cancer rates¹⁵. Cohen JH et al in another study found that 28 servings of vegetables per week decreases prostate cancer risk by 33%, moreover just 3 servings of cruciferous vegetables per week decreased prostate cancer risk by 41%¹⁶. It is worth mentioning here that cruciform vegetables includes: Bok Choy, Broccoli, Broccolini, Cabbage, Cauliflower, Mustard green, raddish and turnip etc¹⁷.

Though research have shown the importance of diet and physical activity in preventing cancers and awareness programs have been introduced and reported but still studies available on awareness programs regarding anticancer impact of vegetables are limited.Yong-chuan Wang et al in their study found that strategies for cancer prevention and control implemented in the USA can be valuable models for China¹⁸. The same can be over extended for other countries.Ken Yamaguchireported cancer prevention programs in Japan¹⁹. These can be valuable modes for cancer control.Fotedar V et al in their study concluded that though the mean knowledge of the population about cancers is good but the knowledge and practices about risk factors had to be reinforced²⁰. Altin C et al in their study concluded that limited cancer literacy instruments are available²¹. Aim of this study is thus to assess the base line knowledge of Dental Graduates about the anti-cancer vegetables with the aim that their knowledge will have an impact on the awareness of the community.

METHODOLOGY

The study was conducted through a 10 instrument questionnaire on a sample consisted of Sixty Four Dental Graduates (24 males and 40 females) from University College of Dentistry, The University of Lahore. After obtaining informed consent they were given a questionnaire. Questionnaire comprised of 10 instruments each testing different vegetables that might have an impact as anti-cancer diet. Data was then analyzed using SPSS 16.0 and frequency and percentage for each instrument for each subject was then calculated.

Questionnaire

Q1 Do you know that diet has an impact in preventing cancers?

Q2. What do you think whether Broccoli has any anticarcinogenic effect?

Q3. What do you think whether Brussels Sprout has any anti-carcinogenic effect?

Q4. What do you think whether Cabbage has any anticarcinogenic effect?

Q5. What do you think whether Cauliflower has any anti-carcinogenic effect?

Q6. What do you think whether Raddish has any anticarcinogenic effect?

Q7. What do you think whether Turnip has any anticarcinogenic effect?

Q8. What do you think whether Spanich has any anticarcinogenic effect?

Q9. What do you think whether Tomato has any anticarcinogenic effect?

Q10. Do you think that this questioner has improved your awareness regarding anti-cancer Vegetables?

RESULTS

Dental Graduates perspective regarding anti-cancer vegetables has been discussed in table 1.

Table 1: Frequency and Percentage of each question used to assess the role of different vegetables as anti-carcinogenic agents.

DISCUSSION

The quality and quantity of diet has direct impact on systemic health²². Considering these effects, our questionnaire comprised of 10 instruments related to anti-cancer vegetables especially cruciform vegetables was presented to each subject and base line knowledge of dental graduates regarding anti-cancer vegetables was assessed. First question was related to the fact that whether they have any idea about the role of diet in preventing cancers; 81% of the dental graduates were aware of this fact in our study.

Amjad Al et al in their study found an anti oxidant to anti-cancer effect of Sulforaphane (SFN) a metabolic by product of cruciferous vegetables especially found in Broccoli¹². Qazi et al in another study found that a natural product Sulforaphane (SFN) with antioxidant properties from broccoli has great potential to be used in chemoprevention²³. John D. Clarke, Roderick H. Dashwood, Emily Ho in their study found that Isothiocyanates (Sulforaphane) found in cruciferous vegetables such as broccoli and Brussels sprouts may lower overall cancer risk, including colon and prostate cancer²⁴. Y Zhang et al in another study have supported the anti-carcinogenic effect ingredients found in Broccoli²⁵. Campas-Baypoli, O.N et al in another study found potent anticancer effect of Sulforaphane (SFN) a by product of Broccoli²⁶. Matsui, T et al in their study also found that Sulforaphane (SFN) exhibit a potent anticancer effect especially in osteosarcomas²⁷. Unfortunately only 9.37% of the Dental Graduates in this study were aware of well known anti-cancer effect of Broccoli.

Brussels sprouts, kale, broccoli and various cabbages were found to possess very potent anti-cancer activities as observed in both epidemiological and laboratory studies^28-32. de Figueiredo SM et al in their study established that Sulforaphane (SFN)  a phytochemical commonly found in cruciferous vegetables such as broccoli, brussels sprouts and cabbages exhibits anticancer effect³³. Unfortunately only 10.94% of the Dental Graduates in this study were aware of well known anticancer effect of Brussels Sprouts.

Cabbage has been reported to possess anti-oxidant and anti-inflammatory effects which may have preventive role in chronic disorders³⁴. Fresh cabbage juice, prepared either separately or mixed with other vegetables such as carrot and celery, is often included in many commercial weight-loss diets, diets that improve the bioavailable content of nonheme iron, as well as alternative therapies for cancer patients^35-37. Renuka DJ , Berla TE in another study found that Sulforaphane (SFN) an isothiocyanate formed by hydrolysis of glucosinolates found in Brassica oleraceae possess anticancer and antioxidant activities³⁸. Unfortunately only 12.5% of the Dental Graduates in this study were aware of well known anti-cancer effect of Cabbage.

A lower cancer incidence has been linked with consumption of cauliflower and cruciform vegetables³⁹. Interestingly, PEITC is an anti-cancer compound found in vegetables and was first reported in 2014⁴⁰. Unfortunately only 9.37% of the Dental Graduates in this study were aware of well known anti-cancer effect of Cabbage.

O’Hare T.J. et al in their study found that radish sprouts have potentially greater chemoprotective action against carcinogens than broccoli sprouts⁴¹.Gutiérrez RMP and Perez RL in their study found that aqueous extract of the salted Radish roots showed antimutagenic activity against Salmonella typhimurium TA98 and TA100⁴². O’Hare T.J. et al in their study found that Daikon and radish sprouts contain high levels of glucoraphenin, a glucosinolate which hydrolyses to form sulphoraphene which is a potent inducer of phase 2 detoxification enzymes and consequently has potential anti-cancer action⁴³. Flavonoids, polyphenolic acids, and other phenolic compounds found in radish exhibit potent anticancer effects⁴⁴. Unfortunately only 7.81% of the Dental Graduates in this study were aware of well known anticancer effect of Raddish.

Turnip exhibit anti-tumorigenic activity due to Indoles found in it^44,45. Robin, Saroj Arora and Adarsh Pal Vig in another study indicated the presence of strong antimutagenic factors and hydroxyl radical scavengers in Turnip seeds⁴⁶. Unfortunately only 7.81% of the Dental Graduates in this study were aware of well known anticancer effect of Turnip.

Recently, a case-control study of dietary factors and gastric cancer in Korean patients reported that high consumption of food rich in nitrate, including cooked spinach, increases the risk of gastric cancer^47,48. In our study 9.37% of the Dental Graduates were aware of anticancer effect of Spanich.

Flavonoids also found in tomato have been demonstrated to inhibit carcinogenesis in vitro and substantial evidence indicates that they can also do so in vivo^49-51. Chick WDW et al in their study found that tomato leaves extract significantly contains purified active fractions with anti-cancer properties⁵². Bhuvaneswari V and Nagini S in their study found that lycopene found in tomat exhibits an array of biological effects including cardioprotective, anti-inflammatory, antimutagenic and anticarcinogenic activities⁵³. Rao AV and Agarwal S.Dietary intakes of tomatoes and tomato products containing lycopene have been associated with decreased risk of chronic diseases such as cancer and cardiovascular diseases⁵⁴. Scolastici C et al in a study found that in addition to its antioxidant properties, lycopene shows an array of biological effects including antimutagenic and anticarcinogenic activities⁵⁵. In our study only 10.94% of the Dental Graduates were aware of anti-cancer effect of Tomato.

In last 89% of dental graduates believed that this questionnaire has improved their base line knowledge about anti-cancer diet. These types of surveys and awareness camps should be conducted at regular intervals to improve the base line knowledge of health professionals and community.

CONCLUSION

This study concludes that base line knowledge about anti-cancer vegetables needs improvement. This may help in changing the dietary habits and thus may help in reducer the increasing incidence of cancers.

Authors’ contributions:

SA Conceived, designed, analyzed and wrote the manuscript, MT contributed in data collection and data analysis, AS contributed in data collection and data analysis.

Disclosure: There is no potential conflict of interest

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1. Associate Professor, Head Department of Orthodontics and Oral Biology & Tooth Morphology, University College of Dentistry, The University of Lahore.
2. Ex-House Surgeon, University College of Dentistry, The University of Lahore.

Corresponding author: “Dr. Saad Asad ” < saad2609@yahoo.com >

Fouzia Mujeeb¹                                      BDS, MCPS

Zaheer Ahmed Soomro²                      BDS

Saqib Rashid³                                        BDS, MSc, FCPS

Tasleem Hosein⁴                                  BDS, FDSRCS

INTRODUCTION

Non carious cervical lesions (NCCL) refer to pathological loss of tooth tissue as a result of factors other than dental caries at the cemento-enamel junction¹. Non carious tooth loss occurs throughout the life of every individual and is thought to be a normal physiological process, however, if the rate at which it is occurring threatens the life of the tooth or becomes a source of concern to the patient, it is then considered to be pathological¹. Tooth surface loss rarely occurs in isolation. It arises as a multifactorial problem involving erosion, abrasion, attrition and abfraction². It has been suggested that the term ‘tooth surface loss’ should be used when it is not possible to identify a single etiological factor. Hardness of the tooth brush and ingredients of the toothpaste are culprits of tooth wear, but this factor particularly depends on the technique of brushing³. Enamel erosion is caused by frequent acidification of the oral cavity by excess intake of citrus juices, carbonated beverages, alcohol consumption and vitamin C. Inappropriate oral habits like nail biting, pipe smoking habitually holding something between the teeth causes atypical tooth loss as well as loss of the entire tooth⁵. Nocturnal bruxism results in non-physiological wear of tooth surfaces⁶. Lesions in the cervical area may cause discomfort to the patient because of hypersensitive dentine and are aesthetically displeasing. These lesions are classified according to their appearance: wedge-shaped, circular, flattened and irregular areas⁷.These shapes range from shallow grooves to broad dished out lesions to large wedge shaped defects with sharp internal and external line angles⁸.

Past clinical studies and observations reveal that these lesions mostly occur on the buccal aspects of the teeth⁹, more commonly found in the maxilla with incisors, canines, and premolars being most commonly affected teeth¹⁰.  Studies have shown that the prevalence of NCCL range from 5 to 85%¹¹.There have been enormous debates on etiology and pathogens involved in NCCL, but even till now uncertainties still exist in the field¹². Various studies have suggested that the cause of NCCLs is multifactorial rather than an individual¹³ in  Differences in diagnosing these lesions in literature, might be the reason of these uncertain results when compared with one another¹⁴. Cervical dentinal hypersensitivity is another factor associated with these lesions. The proportion of teeth with cervical dentinal hypersensitivity associated with NCCLSs increased significantly with age¹⁵. The increase in frequency of these lesions presents us with unique challenges to restore them successfully. Etiology of the lesion must be understood so that we can treat the cause along with providing the restoration.

Previous studies have concluded that the prevalence of non carious cervical lesions is increasing and the identification of risk factors is very important for diagnosis, prevention and treatment. The purpose of this clinical study was to analyze the etiology, assess the factors associated with non carious cervical lesions and to determine the most commonly involved teeth and their inter/intra arch relations. The study of possible factors and knowing about the degree of prevalence of these lesions can be useful in finding ways for preventing and curing them.

METHODOLOGY

This was a cross sectional study conducted in Fatima Jinnah Dental Hospital and College. The duration of this study was of six months and a hundred patients were included in the study. Purposive consecutive sampling was done, the inclusion criteria were; 1) all teeth with non carious cervical lesions, 2) all age groups, 3) permanent dentition. Exclusion criteria included;1) active, untreatable periodontal disease, 2) rampant uncontrolled caries, 3) patients undergoing orthodontic procedure and 4) primary dentition.

The authors examined patients coming to the dental OPD for the presence of NCCLs. The assessment involved a clinical examination and a questionnaire to help determine the cause of the presence of the lesion. Informed consent was taken before asking questions and conducting clinical examination. The questionnaire included was administered to purposive consecutive sampling of patients that came to the dental OPD. The questionnaire included basic patient demographic information (name, age, gender and locality). The patients were asked if they felt sensitivity after blowing air from triple syringe, any aesthetic issues associated with the lesions. A complete medical history and subsequent drug history was taken. History of presence and frequency of vomiting, gastric reflux and heartburn was asked. Inquiries were made about any para-functional (bruxism and teeth clenching), and nervous (nail/ tooth biting) habits. Dietary practices of the patient were analyzed, emphasizing on the frequency of intake of carbonated beverages citric juices and sour foods. Lastly, the patient were asked which was the dominant working hand and whether he was a bilateral or a unilateral chewer.

QUESTIONNARE

1. Do you have any parafunctional habit such as tooth clenching or grinding?
2. Do you chew unilaterally?
3. Do you have or have had regurgitation problem?
4. Do you have any health problems?
5. Have you taken any drug for long period? 6. Do you regard yourself as a nervous person?
6. Do you have sensitivity in teeth?
7. Do you have any aesthetic concern with reference to the lesions?
8. Do you drink acidic beverages like colas or orange juices?
9. Are you right handed or left handed?

After asking the questions, all the patients were clinically examined. A dental mirror and a probe was used under high intensity light. All surfaces of the teeth including the buccal, lingual and palatal were examined from the central incisors to the third molars in both the arches. The tip of the probe was positioned perpendicular to the surface of the tooth and it was moved along the cervical margin to detect any irregularity was found, it was considered to be a non carious cervical lesion. The finding from each tooth was recorded on a table present in each questionnaire.

The data was analyzed on SPSS  version 17. Descriptive statistics and frequencies of the data were determined to know the prevalence of the NCCLs. Chi-square test and

cross tabs were applied to determine the relationship (table no.3). between the number of NCCLs in groups and the associated It was also found that patients with right working hand factors. A p value of less than 0.05 was considered ( P=0.012) had more nccls lesions than those of the left significant.

RESULTS

A total 100 patients (51 males and 49 females) were included, all had at least one tooth with non-carious cervical lesion. The age of the patients ranged from 21 to 70 with a mean age of 49.3(table no.1). The number of lesions per subject in the group with non carious cervical lesions ranged from 1 to 24, with a mean of 9.94 lesions per subject (standard deviation [SD] = 5.231). We found 558 lesions in the maxilla and 436 in the mandible. We found that having sensitivity ( P= 0.471), aesthetic concern ( P= 0.077), diet concerns (P = 0.557), regurgitation ( P= 0.810), medical condition ( P= 0.344), nervous habits

Table no 1: Age in groups in relation to the number of lesions

Table no 2: Non significant variables when tested with the number of lesions in groups

( P= 0.799), drug use ( P= 0.880), Unilateral chewing habits ( P= 0.159) were not associated with the presence
of lesions. We also found that sex of the patient ( P= 0.659) was not associated with the presence of lesions (table.no.2). However we did find significant results in patients with parafuctional habits ( P= 0.039) , suggesting that patients having more than 11 NCCLs had parafuntional habits (table no.3).
It was also found that patients with right working hand ( P=0.012) had more nccls lesions than those of the left handed patients (table no.4).

Table no 3: Relation between NCCLs and Parafunctional habits

Table no 4: Relation between NCCLs and Working hand

First premolars were found to be the most affected teeth (bar chart no.1), and crosstab results between the premolars showed that if there was a lesion in the maxillary first premolar, the mandibular first premolar of the same side was also involved (table no.5a & 5b).

Table no 5a: Relationship between 14 abd 44

Table no 5a: Relation between NCCLs and Working hand b: Relationship between 24 and 34

Bar chart no. 1: Frequency of nccls in fdi notation of teeth

DISCUSSION

Non carious cervical lesions have been found to be more prevalent in aged patients. This is a logical statement, as with the increase in age, the teeth get more exposed to the persistent etiological factors16. Our study showed similar results when comparing four age groups with the total number of nccl, but with patients upto 60 years and above, the results showed decreased nccl. This was suggested to be probable because most patients above 55 years have their teeth extracted rather than treated in Pakistan, and hence the number of lesions were particular to the teeth they had.
Sensitivity tests did not show significant results, concluding that nccl tend to be a chronic process that occurs over an extended period of time, hence allows deposition of secondary dentine occluding dentinal tubules and thereby preventing sensitivity17. These finding are similar with other studies conducted checking sensitivity in relation to nccl. Some researches have shown bruxers having greater incidence of nccl than non bruxers while others have disagreed. Our study showed significant results and stated that there was some association between patients with parafunctional habits and nccl17. As quoted by many studies18,19,20, our study agreed that premolars were the most frequent teeth affected with nccl. This is thought to be because of their anatomical position in the arch of being placed in the center. We further observed the relationship between involvement of premolars of the opposite side of the same arch and opposing arch. The crosstabs showed that there were significant results for the involvement of nccl of the opposing premolars. Which concluded that if a maxillary premolar of left side had nccl, there are more chances of nccl in the mandibular premolar of the same side.Our study also compared the presence of nccls between patients that were left handed and right handed and the results obtained were significant. It was concluded that right handed patients had more chances of nccl than those who were left handed. Other studies which were conducted with similar variables, showed no significance and disagreed with any relation of nccl with the working side21. Our study may have shown different results as the number of patients who were left handed were less (12 %) when compared to those who were right handed (88%). The etiological factors associated with nccl are still unclear amongst practitioners, who differ in identifying these lesions and treat cervical lesions accordingly. The literatures available are inconclusive of establishing any one factor being associated with non carious cervical lesions. Rather, a variety of factors are involved in the formation of non carious cervical lesions. NCCLs being multi-factorial in etiology, the treatment protocol for them requires special understanding of the primary cause. Patients need to be educated regarding the etiologic factors of nccls, so that they may be able to identify and prevent progression of nccls.
This study was conducted in a private hospital setup from patients with non carious cervical lesions only, hence the results cannot be generalized to general population.

CONCLUSION

Within the limitations of our study, we make following conclusions

• Premolars were the most affected teeth
• If a premolar of maxillary arch was affected, it is most likely that the premolar of mandible on the same side will be affected.
• Parafunctional habits were significantly associated with nccls

Authors’ Contributions:

FM conceived the idea, contributed to manuscript writing and collected the data, ZAS collected the data and did the statistical analysis, SR and TH critically analysed the manuscript and gave final approval Disclosure: None disclosed

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4. Brandini DA1, de Sousa AL, Trevisan CI, Pinelli LA, do Couto Santos SC, Pedrini D, Panzarini SR. Noncarious cervical lesions and their association with toothbrushing practices: in vivo evaluation. Oper Dent. 2011 ;36:581-589.
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7. Hirata Y, Yamamoto T,Kawageo T, Sasaguri K, Sato. Relationship between occlusal contact pattern and noncarious cervical lesions among male adults. J.Stomat.Occ.Med. 2010;3:10-14
8. Wood I, Jawad Z, Paisley C, Brunton P. Non-carious cervical tooth surface loss: A literature review. J Dent. 2008; 36: 759-766
9. Sneed WD. Noncarious cervical lesions: why on the facial? A theory. J Esthet Restor Dent. 2011 ;23:197-200.
10. Bernhardt O1, Gesch D, Schwahn C, Mack F, Meyer G, John U, Kocher T. Epidemiological evaluation of the multifactorial aetiology of abfractions. J Oral Rehabil. 2006 Jan;33(1):17-25.
11. Järvinen VK, Rytömaa II, Heinonen OP. Risk factors in dental erosion. J Dent Res.1991;70: 942-947.
12. Jafari Z. The study of possible factors related to NonCarious Cervical Lesions. European Journal of Academic Essays.2014; 1: 45-48.
13. Silva AG1, Martins CC, Zina LG, Moreira AN, Paiva SM, Pordeus IA, Magalhães CS. The association between occlusal factors and noncarious cervical lesions: a systematic review. J Dent. 2013 ;41:9-16.
14. Borcic J, Anic I, Urek MM, Ferreri S. The prevalence of non-carious cervical lesions in permanent dentition. Journal of Oral Rehabilitation 2004;31:117-123
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16. Aw TC, Lepe X, Johnson GH, Mancl L (2002) Characteristics of noncarious cervical lesions: a clinical investigation. J Am Dent Assoc 133: 725-733.
17. Aw TC, Lepe X, Johnson GH, Mancl L. Characteristics of noncarious cervical lesions: A clinical investigation. J Am Dent Assoc. 2002 ;133:725-733.
18. Rees JS1, Hammadeh M, Jagger DC. Abfraction lesion formation in maxillary incisors, canines and premolars: a finite element study. Eur J Oral Sci. 2003;111:149-154.
19. Wood I1, Jawad Z, Paisley C, Brunton P. Non-carious cervical tooth surface loss: a literature review. J Dent.
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20. Tugnait A, Clerehugh V. Gingival recession-its significance and management. J Dent. 2001;29:381-394.
21. Brandini DA1, Trevisan CL, Panzarini SR, Pedrini D. Clinical evaluation of the association between noncarious cervical lesions and occlusal forces. J Prosthet Dent. 2012; 108:298-303.

1. Operative Department, Fatima Jinnah Dental College Hospital, Karachi.
2. Head of Department, Professor, Operative Department, Fatima Jinnah Dental College Hospital, Karachi.
3. Principal, Fatima Jinnah Dental College, Karachi.

Corresponding author: “Dr. Zaheer Ahmed Soomro ” <drzaheersoomro@hotmail.com>

Khurram Parvez Sardar¹                                      BDS, MDS

Yashfika Abdul Bari²                                             BDS

Mansoor Akhtar³                                                     BDS

INTRODUCTION

The term “stress”, as it is currently being used was coined by Hans Selye, who defined it as “the non-specific response of the body to any demand for change”¹. The practice of dentistry has long been associated with high levels of occupational stress. Hermanson reported emotional illness ranked third among illnesses in dentists² and Cooper reported the dental profession is the most stressful of all health professions³. People under stress can have insomnia. Insomnia is one of the causes which stress induces and affect the quality of the sleep. It also causes hyperarousal, which makes the balance between sleep and wakefulness distraught. Laboratory evidence shows that fewer sleep durations of 4-5 hours affect physiological and neurobehavioral functioning in a negative way⁴. It is found that bruxism, mainly, as a response to release daily emotional stress; is more common in depressed, anxious and emotionally stressed individuals⁵.

De Leeuw et al consider that muscle dysfunction and associated pain are often the results of stress-induced muscle hyperactivity. The muscle dysfunction determined by the stress can cause changes in the temporomandibular joint⁶. The hyperactivity in elevator mandibular muscles increases intra-articular pressure and biomechanical alterations of temporomandibular joint with the result micro traumatic deterioration of the joint capsule and/or the attachment disc can develop⁷.

The term stress describes external demands (physical or mental) on an individual’s physical and psychological wellbeing⁸. Stressors associated with dentistry include time and scheduling pressures, managing uncooperative patients and the highly technical and intensive nature of work^9-12. This stress can be the prime factor to depression, anxiety, substance misuse, absenteeism, diminished work efficiency, and burnout (a term that describes the experience of long-term work-related exhaustion and diminished interest)¹³. The origin of this occupational stress may have their origin in the educational process as dental students experience high levels of stress during training¹⁴.

The undergraduate education is a delicate period in a student life.  The students from professional courses do feel a great amount of burden in dealing with academic stress and anxiety. This can occur during the transition of the students from an intermediate to a professional academic status¹⁵. Undergraduate students need to cope up with the academic and social demands that they may encounter in university studies in their preparation for professional careers¹⁶.

The parafunction in dentistry refers to those actions of the stomatognathic system that are considered to fall outside of functional activities. Lip and cheek chewing, fingernail biting, and teeth clenching are examples of parafunctional activity. Out of different activities of parafunction, a literature on teeth grinding exceeds the rest¹⁷. Bruxism is an involuntary, parafunctional, excessive grinding, clenching, or rubbing of the teeth^18,19. It is a potentially disparaging habit that results in tooth wear, damage to the structure of the surrounding teeth, inflammation and recession of the gums, increased risk of periodontal disease, muscle pain, and temporomandibular joint (TMJ) dysfunction.’ These symptoms are also associated with headaches, jaw aches, and stiffness or tightening of the shoulders and neck²⁰. It is also reported that individuals with sleep bruxism are three to four times more likely to experience jaw pain and limitation of movement than people who do not experience sleep bruxism^21,22.

The literature has been documented regarding the relationship between neurological and psychiatric and psychopathology and parasomnia (a subgroup of sleep disorders) includes bruxism²³.

It is believed that the stress has universally become a phenomenon that has immensely developed in recent years. The humans have learnt to adapt physiologically to this condition. The stress and the social situation at work are strongly linked to disturbed sleep and impaired awakening, the inability to stop worrying about work during free time generates an important link between stress and sleep leading to parafunctional habits²⁴. Hence, It is important for dental schools to identify stress levels among its students when planning the curriculum and working environment for dental education to create a more student-friendly, less stressful, atmosphere²⁵. Therefore, the aim of the study was to find out the association among stress , insomnia and parafunctional habits according to the academic year of clinical dental students.

METHODOLOGY

It was a descriptive cross-sectional qualitative study carried out using a self- administered questionnaire among undergraduates (second year, third year, and final year) and postgraduates working at dental institutes of Dow University of Health Sciences. The questionnaire covered demographic question, sleep related questions, stress consequences, occupational stressors and stress reduction methods. The data obtained via questionnaire was analysed with SPSS-16. Descriptive analysis was made regarding the data and result was drawn in the form of tables. Chi-square test was used to study the associations between variables. The purpose of this study was communicated to the students, and student participation in the research was voluntary. The response rate was 96.5%.

RESULTS

This study was carried out among undergraduates and postgraduates. Table 1 shows the demographics of the study population. Table 3 showed that more than half of the population go to bed late (n=312, 53.9%) and find difficulty getting into sleep (n=375, 64.8%). Table 3 also represents the consequences of stress respondents suffered..  Out of different consequences, it was found that most common stress-related consequence was grinding their teeth at night (n=322, 55.6%) Table 3 showed the occupational problems that have to be suffered by the students. More than half of the dental students were under occupational stress (n=322,

55.6%) and less than half of the respondents reported to have disturbed academic (n=269, 46.5%) and clinical skills (n=213, 36.8) due to stress. Table 2 is related to stress reduction methods. Respondents were asked that what measure they usually take when in time of stress. Out of the different methods listening music (n=366, 63.2%) was found to be most common stress reduction method. Table 3 also pertains to the association between insomnia and stress and parafunction. This association was found to be significant (p<0.05). Table 3 also shows that the factors which were associated with parafunctional activities was also associated with sleep disturbance and occupational stressors.

DISCUSSION

Dental education is perceived as being stressful course²⁶. The students have a high level of fears and insecurities which make them likely to disturb their mental and physical health. This made the study to choose dental students, as their sample population to highlight the association of stress with improper sleep and developing parafunctional habits^15,16.

It is found that most of the dental and medical students go to bed late due to tough and lengthy academic syllabus and long study hours. Their sleep is improper and they have to further experience daytime sleepiness and tiredness in the morning²⁷. The day time nap becomes important for the students. Waking up too late and having difficulty getting into sleep makes them susceptible to exert pressure on their masticatory muscles and apply external pressure on their occlusal surface of the tooth to release the stress they are going through. This habit for a prolonged period of time makes their temporomandibular joint tender and it becomes painful on opening, closing and chewing. Applying pressure for long hours also makes the muscles numb, so the numbness in mouth was reported^17-22.

The most frequent consequences of stress, according to our study, were feeling restlessness and frustration, teeth grinding, numbness in mouth, pain in temporomandibular joint^9-12. The high prevalence of these consequences was further analysed and it was revealed that high prevalence of difficulty getting sleep was a significant factor in developing these consequences. Therefore improper sleep is to an extent found to be associated with teeth grinding^5,28.

The main result was that the experience of stress was the most signi?cant factor associated with frequent bruxism among the dental students. The bruxers were also found to have pain in temporomandibular joint and they were found to be restless and frustrated^21,22. The study also revealed, there is a significant association found in respondent between difficulty falling asleep and teeth grinding⁵.

The dental students participated in this study were found to have occupational stress. The majority have fear of failure in their examination, unemployment and respondents who had teeth grinding habit also has high level of these fear. 14 Other factors, regarding occupational stressors were also found in respondents who were bruxers and have pain in temporomandibular joint.

This study revealed that stress was found to be associated with sleep disturbance leading to development of parafunctional habits. According to the study, the students who were under high academic pressure were found to be restless and frustrated due to fear of failure and unemployment which leads to their teeth grinding habits and their jaw joint gets affected and they start getting pain in their temporomandibular joint. The study revealed that improper sleep was major factor in developing these habits. It should be recommended that students should take proper sleep in order to get rid of their parafunctional habits and they should use stress reduction methods to get less affected of the stressful conditions. Thus, stress reduction program could be implemented. Such programs for dental students as including specific courses, stress-reduction sessions, introduction to behavioural sciences and faculty incorporated advising systems foster coping behaviours that are useful on a daily basis, as well as preventative measures to reduce chronic stress effects. Students should also be advised to take proper sleep so that students can perform better in their dental environment.

CONCLUSION

It was concluded that there was significant association among improper sleep, stress and parafunctional habits in undergraduate and postgraduate dental students at Dow University of Health Sciences.

Author Contribution:

KPS conceived the project, designed Questionnaire and made significant contribution to reviewing and re-writing of article, YAB contributed to questionnaire designing, data collection, write up of introduction & methodology, MA did the data collection, write-up of results & discussion. Disclosure: None declared.

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5. Carvalho AL, Cury AA, Garcia RC. Prevalence of bruxism and emotional stress and the association between them in Brazilian police officers. Braz Oral Res. 2008 ;22:31-5..
6. De Leeuw R. Orofacial pain: guidelines for classification, assessment, and management. 4th edition. Chicago: Quintessence Publ. Co.; 2008
7. Praveena KS, Rai R, Easwaran MA, Easwaran B. Temperomandibular disorders Clinical and Modern Method In Differential Diagnosis: IOSR J Dent Med Sci 2014;13:17
8. Kumar S, Dagli RJ, Mathur A, Jain M, Prabu D, Kulkarni S. Perceived sources of stress amongst Indian dental students. Eur J Dent Educ. 2009;13:39-45..
9. Westerman GH, Grandy TG, Ocanto RA, Erskine CG. Perceived sources of stress in the dental school environment. J Dent Educ 1993; 57: 225-231
10. Acharya S. Factors affecting stress among Indian dental students. J Dent Educ 2003; 67: 1140-1148.
11. Heath JR, Macfarlane TV, Umar MS. Perceived sources of stress in dental students. Dent Update 1999; 26: 94-98, 100.
12. Rajab LD. Perceived sources of stress among dental students at the University of Jordan. J Dent Educ 2001; 65: 232-241.
13. Tangade PS, Mathur A, Gupta R, ChaudharyS.Assessment of stress level among dental school students: an Indian outlook. Dent resJ2011;8: 95.
14. Freeman R., Main JR, Burke FJ. Occupational stress and dentistry: theory and practice. Part I. Recognition. Br Dent J 1995;178: 214-17.
15. Mane AB, Krishnakumar MK, Niranjan PC, HiremathSG, Mane AB.. Differences in perceived stress and its correlates among students in professional courses. J clindiag resh 2011;5:1228-33.
16.  Pfeiffer D. Academic and Environmental Stress Among Undergraduate and Graduate College Students: ADoctoral University of Wisconsin-Stout, 2001.
17. Bender, Steven D. Occlusion, Function, and Parafunction: Understanding the Dynamics of a Healthy Stomatagnathic System. ADA CERP (2009).
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20. Gina P, Chrobak V, Petrie J. “The social and psychologic factors of bruxism.” dentistry Prostht Dent 1991:65; 443-46.
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1. Assistant Professor. Department of Science of Dental Materials Dr.Ishrat-ul-Ebad Khan Institute of Oral Health Sciences Dow University of Health Sciences.
2. House Officer. Dr.Ishrat-ul-Ebad Khan Institute of Oral Health Sciences Dow University of Health Sciences
3. Department of Prosthodontics Dr.Ishrat-ul-Ebad Khan Institute of Oral Health Sciences Dow University of Health Sciences

Corresponding author: “Dr. Khurram Parvez Sardar”<dr_khurramaprvez@hotmail.com  >

Haroon Rashid¹                                       BDS, MDSc

Asma Naz²                                                 BDS, FCPS

Ahad Shahid Ahmed³                           BDS, MSc

Muhammad Zuhaib uddin⁴                BDS

INTRODUCTION

Two major factors for a successful complete denture are superior retention and support. This is achievable once a clinician is able to record an accurate final impression and replicating the functional depth of the sulci and entire denture bearing area¹. However; there may be scenarios where the quality of the denture bearing tissues is not in a favorable state. Resorbed, displaceable or flabby tissue may be present which may give rise to common complaint of a loose denture. The prevalence of flabby ridges was found to be 5% in edentulous mandibles and 24% in edentulous maxilla². It has been reported in the literature that when mandibular anterior teeth cause trauma in the anterior maxillary region because of higher occlusal forces, fibrous tissue hyperplasia occurs and the mucosa becomes highly mobile and loosely attached to the underlying bone¹. The flabby tissues of residual alveolar ridges could also be a result of extractions which were uncontrolled and unplanned.

Several techniques for overcoming the problem of flabby ridges have been described in the literature. A technique which involves the use of two impression materials has been described in the literature. It involves the use of custom tray with zinc-oxide eugenol over normal tissues and impression plaster over the flabby tissue areas⁴. Crawford & Walmsley⁵ described a technique which involves the use of two trays and the impression is taken with two different materials. These impressions are then oriented intra-orally. Osborne⁶ described the technique termed as “window” impression technique in which a custom tray made tray is fabricated with a window over the flabby tissues. Initial impression of the normal tissues is taken using the tray with amuco-compressive impression material. When the material is set, the impression of the flabby tissues is taken through the window using low viscosity impression plaster.

There have been recent advancements in material sciences and newer materials are available in the market having different consistencies and methods of dispensing. A practitioner is thus, able to choose the material that is most suitable for the patient also. The aim of the current paper is to review various methods of management of flabby ridges and to describe the classic window impression technique.

MANAGEMENT OF FLABBY RIDGES

Crawford & Walmsley⁵ have described three approaches for the management of flabby ridges:

a. Surgical Removal

Surgical removal can be done in patients with no medical and dental contraindications and has an advantage that it produces a firm denture-bearing area. This results in fabrication of a prosthesis which is stable and retentive in most cases. However; the procedure should not be performed here there is reduced height of residual alveolar ridges⁷.

The area from where the tissue is excised/removed usually requires replacement with the denture base material which leads to an increase in the overall bulk of the prosthesis. This could actually result in a prosthesis which is un-retentive. It could be argued that although presence of flabby ridge leads to a sub-standard retention of a denture, it may be desirable than having no ridge at all.Ghazali et. al.,⁸ studied the effects of surgical removal of soft tissues and flabby ridges from edentulous maxillary alveolar ridges in five subjects. Their results indicated that it is beneficial that early surgical removal of the flabby tissues is carried out.

b.  Implant Retained Prosthesis

Treatment of edentulous patients using dental implants is considered to be the treatment of choice nowadays⁹. Implant over dentures (IOD) have gained worldwide popularity, acceptance and significantly improve the quality and standard of life for patients with edentulous ridges. The prosthesis retained by dental implants is retentive, stable and often requires good maintenance of both the prosthesis and other components¹⁰.  Continued research related to IODs has resulted in multiple options and combinations for IOD attachment systems with varying success. An IOD, in comparison to fixed implant supported prosthesis is economical initially and the surgical procedure is often easy to perform. However; it is worth mentioning that despite of reduced initial expenses, the cost of maintenance of an IOD could be substantial. As far as time and finances is concerned, the long term maintenance costs are higher. Other factors that could hinder implant placement include discomfort and inconvenience, the general health status of the patient and the risk of complications and failure of endosseous implants. Overdenture abutments, whether it is a retained root or an implant, preserves the height of alveolar bone and helps in stabilization of complete dentures particularly in the lower jaw. The option of retaining roots is a cost effective mean with no invasive therapy. General practitioners should consider retaining the roots as they serve as a useful platform for over-dentures, especially for those individuals who are old aged.

Maxilla has higher prevalence of flabby ridge as compared to mandible and implants in maxillary regions are not as successful as mandibular implants and success rates of about 79% to 82% have been

reported^11,12.Decreased success rates could have been due to placement of short endosseous implants into high vascular bone with poor volume and low-density.

c. Conventional Prosthodontics

Where implant placement and surgical excision is not an option, conventional prosthodontics techniques are available which may be beneficial in overcoming the problem of flabby ridges. During impression, when mobile flabby tissue is displaced from its resting position, there is a very high probability that an unfavorable denture bearing area is produced. Literature describes two ways of overcoming this problem conventionally. One method is to record a muco-displacive impression which aims to compress the flabby tissues. This will allow functional support from the flabby tissues and by replicating the contour of the alveolar ridge during function by the occlusal forces. The other way to overcome is by recording a mucostatic impression that aims to gather support from other areas of the ridge and maximizes retention, stability and support.

Many techniques of overcoming flabby ridges have been described in literature. These include the one part impression technique¹³, controlled lateral pressure technique¹⁴, palatal splinting technique and two part impression technique or the window technique⁶. The author would like to specifically discuss the two part impression/ window technique.

d.  Two Part Impression or Window Technique

This classic technique was first described in 1964 by Osborne⁶ and it ensures that flabby tissues are not distorted during impression taking as no excessive force is exerted by the tray over mobile tissues. The initial impression is recorded using impression compound and the displaceable tissue is marked on the recorded impression and is transferred to the study cast. A closed fitting custom made tray is constructed which does not cover the displaceable soft tissue. This is usually achieved by creating a window over the flabby tissue area. Border moulding is performed and final impression of the entire supported ridge is recorded using zinc-oxide eugenol impression paste or medium bodied silicone impression material. The impression of the flabby tissues is then recorded by syringing impression plaster or by dispensing the light bodied silicone impression material.

There is a variation in the design of the custom made

tray and it could be completely uncovering the section of the arch or a window may be created in the areas where flabby mobile tissue is present. In majority of the custom made tray types, a modification of the placement of the tray handles is necessary. The window type modification is advantageous since it allows for appropriate border correction before proceeding ahead with the second stage of the impression.

CASE REPORT

A 72 year old male patient reported to the Division of Prosthodontics, Ziauddin University Hospital, Karachi, complaining of loose and ill-fitting maxillary and mandibular complete dentures. The patient had been edentulous for the past 9 years and had worn three sets of complete dentures previously. A thorough clinical examination was performed and flabby mobile tissue was observed in the anterior region of the upper arch alongwith severely resorbed lower mandibular ridge.

Treatment plan was discussed with the patient and an option of surgical removal of the upper mobile tissue followed by a conventional complete denture and placement of a lower implant retained over-denture. However; patient could not afford the cost of dental implants and was not in a favor of a surgical procedure. It was finally decided that new set of maxillary denture using the “Window Technique” would be fabricated and a new set of mandibular dentures were to be fabricated using the neutral zone impression technique. The management of maxillary edentulous ridge was carried out as follows:

1. Primary impression of the upper edentulous ridge was recorded using high viscosity irreversible hydrocolloid (Cavex Holland, BV) (Figure 1). The impression was

Figure 1: Maxillary preliminary impression

poured in the laboratory and preliminary cast was obtained. 2. The flabby mobile tissue was marked on the cast and a custom made tray was fabricated using self-cure acrylic resin. The borders of the custom-made trays were kept 2mm short of the vestibules.

3. A window was created on the custom made trays using acrylic trimming burs. The size of the window opening was determined using the size of the displaceable tissues and two tray handles were constructed (Figure 2).

Figure 2: Custom-made tray with a window in anterior maxillary region

4. Border moulding for the maxillary arch was carried out using green-stick impression compound (MetroDent) and secondary impression was recorded using zinc-oxide eugenol impression paste (Cavex, Holland, BV). Excess impression material at the peripheries of the window was trimmed away carefully using a scalpel (Figure 3). 5. The impression was re-inserted in the patient’s mouth and thin mixed impression plaster was injected through

Figure 3: Final impression of the maxillary denture bearing area not involving the flabby tissues

the window over the flabby mobile tissues. The tray was held with light pressure and care was taken to avoid tissue distortion during the procedure.

6. The material was allowed to set and the impression was removed with care, disinfected and sent to the laboratory for further processing (Figure 4). 7. The usual remaining denture fabrication steps were

Figure 4: Completed final impression

carried out, denture was delivered to the patient and postoperative instructions given.

DISCUSSION

Prosthodontic management of flabby ridges can be carried out effectively by various means. The choice of best treatment modality is dependent on various factors including the medical health status of the patient and the degree of displaceability of the flabby tissues. Surgical excision offers promising results but may also lead to decreased sulci depth.  It is worth mentioning that surgical intervention i.e. the excision of flabby tissues, bone grafting and implant placement may not always be possible in elderly patients and denture fabrication using the “window technique” may be the only successful alternative.

Osborne J⁶ used two different impression materials i.e. zinc-oxide eugenol and impression plaster for flabby ridge management. In their technique, they used two separate trays and impression materials were used to record the normal and the flabby tissues which were related intra-orally. The technique described in the current case report is similar to that of Watson¹⁵ who also fabricated a custom made tray with a window, used impression plaster to record the impression of the mobile flabby tissues and zinc-oxide eugenol to record the impression of the remaining tissues of the maxillary ridge.

Impression plaster is a mucostatic impression material with very limited use in clinical dentistry nowadays. It is very effective in scenarios where minimum displacement of the tissues during impression taking is required. The material is difficult to handle, messy and is not well tolerated by patients¹⁶. Impressions recorded using impression plasters are also difficult to pour in the laboratory¹⁷. However; the material is costeffective, offers good dimensional stability and allows the clinician to control the setting reaction.

The authors would also like to encourage the clinicians to properly record the orientation of the occlusal plane during recording of the jaw relationships. The use of a suitable face-bow and set up of teeth on a semi-adjustable articulator is highly recommended as this will help to establish a suitable occlusal scheme with balancing contacts during excursive movements. If this is not achieved, the denture already seating on mobile tissues will be further destabilized.

CONCLUSION

The window technique described in the current paper is simple, cost effective and does not require an additional clinical visit. The materials described in the current case are readily available but authors would still encourage the use of addition cured silicones as they offer better clinical handling and excellent dimensional stability. Effective communication with the dental technician is also encouraged for a better treatment outcome.

ACKNOWLEDGEMENT

The authors would like to acknowledge Mr. Abdul Waheed, acrylic technician in the dental laboratory of the department of prosthodontics, Ziauddin University, for his expertise and help during laboratory stages of the denture fabrication.

Author Contribution:

HR made the original design of the manuscript, and performed proof reading, AN wrote section 2 and 3 of manuscript and performed proof reading, AS wrote discussion and MZ took photographs and performed proof reading. Disclosure: None disclosed

REFERENCES

1. Lynch CD, Allen PF.Management of the flabby ridge: using contemporary materials to solve an old problem. Br Dent J. 2006 Mar 11;200:258-61.
2. Carlsson G E. Clinical morbidity and sequelae of treatment with complete dentures. J Prosthet Dent 1998; 79: 17-23.
3. Kelly E. Changes caused by a mandibular removable partial denture opposing a maxillary complete denture. J Prosthet Dent; 1972; 27:140-50.
4. Magnusson B, Engström H, Kahnberg K. Metaplastic formation of bone and chondroid in flabby ridges. Br J Oral Max Surg. 1986; 24: 300-305.
5. Crawford R, Walmsley A. A review of prosthodontic management of fibrous ridges. Br Dent J. 2006; 199: 715-719.
6. Osborne J. Two impression methods for mobile fibrous ridges. Br Dent J. 1964; 117: 392-394.
7. Grant A A, Johnson W. Removable denture prosthodontics. 2nd ed. p 61. Edinburgh: Churchill Livingstone, 1992.
8. Ghazali S, Nilner K, Wallenius K. The functional deformation of maxillary complete dentures in patients with flabby alveolar ridges. Part II: After surgery. Swed Dent J. 1991;15(2):63-70.
9. 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.
10. Rashid H, Hanif A, Vohra FA, Sheikh Z. Implant overdentures: A concise review of the factors influencing the choice of attachment systems. J Pak Dent Assoc 2015; 24: 63-69.
11. Goodacre C J, Kan J Y K, Rungcharassaeng K. Clinical complications of osseointegrated implants. J Prosthet Dent 1999; 81: 537-552.
12. Becker W, Becker BE, Alsuwyed A, Al-Mubarak S. Long-term evaluation of 282 implants in maxillary and mandibular molar positions: a prospective study. J Periodontol. 1999 Aug; 70 :896-901.
13. Lamb D J. Problems and solutions in complete denture prosthodontics. pp 57-60. London: Quintessence, 1993.
14. Grant A A, Heath J R, McCord J F. Complete prosthodontics: problems, diagnosis and management. pp 90-92. London: Wolfe, 1994.
15. Watson RM. Impression technique for maxillary fibrous ridge. British Dental Journal 1970; 128:552.
16. Moonsammy VJ, Owen P, Howes DG. A comparison of the accuracy of polyether, polyvinyl siloxane, and plaster impressions for long-span implant-supported prostheses.  Int J Prosthodont. 2014 Sep-Oct;27:433438.
17. Thongthammachat S, Moore BK, Barco MT 2nd, Hovijitra S, Brown DT, Andres CJ. Dimensional accuracy of dental casts: influence of tray material, impression material, and time. J Prosthodont. 2002 Jun;11:98-108.

1. Assistant Professor& Head, Department of Prosthodontics, Ziauddin University, Karachi, Pakistan.
2. Assistant Professor and Head, Department of Prosthodontics, Jinnah Medical & Dental College,  Karachi, Pakistan.
3. Research Trainee, Faculty of Dentistry, McGill University, Montreal, Canada.
4. Muhammad Zuhaib uddin. Postgraduate trainee, Dow University of Health Sciences, Karachi, PakistanCorresponding author: “Dr. Haroon Rashid ” < drh.rashid@hotmail.com >

Atif Saleem Agwan¹                                       BDS, FCPS

Zeeshan Sheikh²                                            Dip.Dh, BDS, MSc, PhD

Haroon Rashid³                                             BDS, MDSc

INTRODUCTION

Successful root canal therapy depends greatly on the quality of cleaning and shaping of the entire root canal system¹. To achieve this a clinician must have good knowledge of the canal morphology and configuration². The most common reason of endodontic failure isapical percolation³. This is often due to improper/incompletecanal obliteration or by leaving acanal completely unfilled⁴. Very often, a canal may be left unfilled or under filled because the clinician has failed to recognize its presence. Hence, it is of immenseimportance to identify all canals present in the tooth/teeth being endodontically treated and to prepare them accordingly.

A variation exists in the frequency of occurrence ofthe number of canals in every root, and the incidence of fusion and the number of roots^5-7.These variations can be seen in canal morphology of teeth and could be due to differences in ethnic background⁸, age^9-11, and gender¹², 13 of the populations. Most of the maxillary permanent first molars have three roots and usually four canals¹⁴. The mesio-buccal roots have two canals whilea single canal is present in each of the disto-buccal and palatal roots respectively^14-15. The second canal,known as mesiobuccal 2(MB2) can be normally located in a palatal or mesiopalatal direction relativeto main buccal canal and variation exists in their frequency that is between 18% and 96%^16-19. MB2 canals have been reported less significantly in many clinical studies as compared various in vitro investigations^20-22.

• Weine has categorized root canal system in each root and has described four different configurations^23,24

Weine also mentioned that high failures of endodontic therapy of the maxillary first permanent molar is very likely due to the failure to locate and obturate the MB2 canal²³. One of the reasons for using Weine’s classification in the current study was that it mentions about the exit position of the apical foramen. In a retrospective investigation of patients, it was shown that in root treated maxillary first and second molars, only 9 to 18% of MB2 canals were located and prepared respectively¹⁷. However, Neaverth et al⁹ reported the location and treatment of 77.2% MB2 canals in maxillary first molars. The objective of this study was to evaluate the incidence of MB2 canal in maxillary first molars of a Saudi sub-population that was referred to the clinics for primary endodontic treatment.

METHODOLOGY

A total of 100 Saudi patients were included in this study that required primary endodontic treatment in maxillary first molars. Consent was taken and forms were signed by the patients. Patients included in this study were systematically healthy. When adequate anesthesia was achieved and isolation was done using rubber dam, the tooth was accessed for pulp chamber opening. The access cavities on the teeth were modified into rhomboidal shape so that the search for the second canal could be facilitated. A groove was made at the floor of the pulp chamber, lingual to the mesio-buccal canal orifice, followed by a sub-pulpal groove between mesiobuccal and palatal orifices. This groove was continued where the sub-pulpal groove between the mesiobuccal and palatal orifices diminished or the mesiolingual orifice was located.  Canal irrigation was done profusely using 2.5% sodium hypochloride solution and floor of the chamber was dried by the use of suction tip prior to inspection of canal orifice. Using orascoptic loupes (Orascoptic, 2.5 x), an explorer (starlite DG16) was engaged from the distal towards the mesial so that the localizing the MB1 opening could be done and a straight-on and distal angle radiographs were recorded for each working length of the instrument.

When the working length determining instrument appeared to be off-center in the root on a distal projection X-ray radiograph, a second canal was suspected and when two separate files or gutta-percha points were seen radiographically at working length, then it was confirmed that the mesio-buccal root had two canals with two separate apical foramina. However, a type 2 Weine configuration (two canals exiting from one foramen) were suspected, when placement of an instrument in one MB canal impeded the full length placement of an instrument in other MB canal. Clinically this can be confirmed when the instrument in one canal obstructs the placement of another endodontic file in the other canal or when a GP point placed at the working length of one canal is scored by a file placed in the other canal²⁶. Data were analyzed using chi-square testing. A probability level of P = 0.05 was considered to be statistically significant.

RESULTS

Overall mean age of the participants in the study was 29 + 3 years and there were 53 males and 47 females. Left and right maxillary first molars were 54% and 46% respectively and MB2 canal was found in 45% of the teeth (Table 1). In the maxillary first molars examined,

Table 1. (n=100)

Table 2. Type of MB Canal in different age groups.

Table 3. Comparison of MB canal type in various age groups according to Weine’s Classification

Table 4. Comparison of Gender with presence of MB2 Canal and exit of MB canal 2 via one or two foramen

Table 5. Comparison of Gender and exit of MB canal 2 via one or two foramen

females as compared to 69% and 31% in males respectively. This association between the gender and canal configuration was found to be statistically insignificant(P > 0.05), (Table 5)

DISCUSSION

The purpose of the current study is to review the literature and to determine the occurrence of MB2 in maxillary first molar in a Saudi sub-population that was referred to the clinics for primary endodontic treatment. Second mesiobuccal canal was found in 45% of the teeth. Further, MB canal 1 was present in both genders while 36% females and 55% males had a second MB canal. The first MB canals exited from one foramen while 64% and 36% of the second MB canals exited from one and two foramens respectively

The teeth that most frequently require endodontic therapy in the permanent dentition are the maxillary first molars^7,25 and they also have the highest rates of

failure ^8,26. It is believed that this is primarily due to non identification of MB2 canals in mesio-buccal roots²⁷. These endodontic failures due to non-treatment of missed canals should be kept in mind before performing treatment ^28,29. Literature clearly indicates the presence

of 2nd mesio-buccal canal in the most of upper molars ³⁰. It has been shown in clinical studies that up to 93% of the maxillary first molars examined have two MB canals²⁸. However, contrary data published by Sempira and Hartwell³¹ revealed that  the 2nd canal in mesiobuccal were found in only 33% of maxillary first molars. Some studies have compared in vivo versus in vitro results regarding MB2 canal presence or absence. Seidberg et al³² had reported in an in vivo study that 33% of the teeth studied (n = 201) had MB2 canals and the percentage increased to 62% (n = 100) in their in vitro investigation. In a study conducted by Pomeranz and Fishelberg, 31% of the teeth studied in vivo had a 2nd mesio-buccal canal as compared to 69% of the teeth in vitro (n = 100 for both studies)²⁰. Our clinical study also confirms the presence of additional second MB canal in mesio-buccal roots of maxillary first molars. We found out that 45% of the first molars had a second MB canal and it may be concluded from our data that all maxillary first molars observed had the first MB canal and approximately half (45%) had the second MB canal as well. As majority of these 2nd canals can only be effectively identified by means of an operating microscope³³, this probably explains the results of our study. The numbers observed would be expected to increase if the identification of the MB2 canal was being performed using a microscope.

It has been reported that between 24% and 55% of MB2 canals are completely separate with separate foramina in the apical region of the root. Also, 24% to 54% of MB roots have two separate canals but have a single apical foramen^28,30,33. In our study, we observed that all of the MB1 canals exited from one foramen. Conversely, 64% of the MB2 canals exited via one foramen and 36% from two foramina. Our finding that maxillary first molars (36%) having two separate apical foramina in the mesiobuccal root is similar to the average of 30.6% which has been reported in previous clinical investigations^24,29,34. Neaverth et al⁹ reported that there were 61.8% of maxillary first molars which had two canals and two apical foramina.

It is a known fact that there is a great variation in morphology or the roots and the canals. However, there is no information regarding ethnic background, age and gender in published literature and conflicting reports with respect to gender and the number of canals are available ^13,22,35. Our results show no statistically significant difference to report between males and females. A study by Weine et al²⁴ concluded that incidence of MB2 canals in a Japanese population was not different from incidence of MB2 canals reported in another ethnic background. As far as age is concerned, it has been reported that the number of MB2 canals decreases with age most likely because of calcification^9,22,29. Interestingly, in our study we also observed a decrease in MB2 incidence with regards to increasing age of the patients but this was not statistically significant. It has been observed that those patients who are older have  one treatable canal in the mesio-buccal root as compared to patients who are younger ^9,29. Although it is very likely that that canals become smaller with increased age, it is also quite unlikely that they would completely disappear²⁹.

The use of loupes and/or surgical operating microscopes in recent clinical investigations has resulted in increased detection rates of the MB2 canals^18,28,31,36. The result of the use of magnification on the incidence of MB2 canal has been evaluated in a study by Buhrley et al. 36. The 2nd MB canal was reported in 71% of the maxillary molar teeth when an operating microscope was utilized for detection. Using loupes, MB2 canals were found in 62% of the teeth 36. As one would expected, the lowest numbers of MB2 canals were found in the group which was performing root canal therapy without the use of any magnification device.

In two in vitro studies conducted^18,29, a light measuring microscope and a scanning electron microscope (SEM) were used to inspect extracted teeth. Access and visibility were unhindered by the removal of teeth crowns and an incidence of 90% and 95%, for the MB2 canals was reported respectively for the two studies. Clinical search and identification of MB2 canals may be assisted and improved by high-quality illumination, magnification and an access cavity preparation that would allow maximum visibility and access ultimately.

This current study has limitations due to its small sample size as well and the use of conventional diagnostic aids i.e. periapical   radiographs.  Although the radiographs play an important role in assessing the root canal morphologies but do not provide complete details of the complexity specially the bucco-lingual dimentions. Newer diagnostic tools like CBCT gives accurate details of the morphology and offer promising results. Another limitation is that in the current study only dental loupes were used as means of locating the canals and authors believe that the use of dental microscope would have provided superior magnification and illumination and hence more chances of locating MB2 canals in maxillary first molars.

CONCLUSION

In this study, maxillary first molars were focused upon from Saudi patients referred for primary endodontic treatment. In addition to all maxillary first molars having the first MB canal, 45% of the teeth had the MB2 canal present. Furthermore, 64% of the MB canals exited from one foramen, whereas, 36% of the MB canals exited via two foramens. There were no statistically significant differences observed on the basis of gender or age variation. Identification and treating theMB2 canals in maxillary first molars may pose a challenge. However, the inability to identify, locate and treat it properly may lead to endodontic failure. The increase in use of headlamps, surgical telescopes and modified access preparations is likely to increase the incidence of treatable MB2 canals with improved treatment outcomes.

Authors’ contributions:ASA wrote and designed manuscript, ZS did the statistics and wrote conclusion, HR reviewed and corrected grammatical mistakes and design of the manuscript. Disclosure: None disclosed

REFERENCES

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1. Northern area Armed Forces Hospital, King Khalid Military City, Kingdom of Saudi Arabia.
2. Faculty of Dentistry, University of Toronto. Room 222, Fitzgerald Building, 150 College Street, Toronto, ON M5S 3E2, Canada.
3. College of Dentistry, Division of Prosthodontics, Ziauddin University, 4/B, Clifton, Karachi, Pakistan.

Corresponding author: “Dr. Atif Saleem Agwan ” < dratifagwan@yahoo.com >

Moiz Ahmad Khan¹                                       BDS, MS

Sharjeel Bashir²                                             BDS

Farhan Raza Khan³                                      BDS, MS, FCPS

Fahad Umer⁴                                                   BDS, MSc

Syed Mahmood Haider⁵                              BDS, MSc, FFDRCSI, FDSRCS

Tuba Hasan⁶                                                   MBBS

INTRODUCTION

Alveolar osteitis (AO) is an important complication following dental extractions by general dentists and specialists alike.^1,2 Being an inflammatory disease, it is defined as “the postoperative pain in and around the extraction site, which increases in severity at any time between day one and day three after the extraction, accompanied by a partially or totally disintegrated blood clot within the alveolar socket with or without halitosis.”.³ Other names used in literature are dry socket, alveolalgia, alveolitis sicca dolorosa, localized osteomyelitis, fibrinolytic or post-operative alveolitis, or septic or necrotic socket.⁴

The etiology of the disease is not clearly known⁵, but various predisposing risk factors have been identified such as smoking, use of contraceptives, pericoronitis, poor oral hygiene, bone remnants in the socket, trauma during extraction and dislodgement of blood clot from the socket⁴, ^5-8 The level of surgical skills during extraction have also been linked with AO.^9,10 Systemic factors associated with AO are diabetes, vitamin C deficiency, bleeding disorders and bone diseases such as Osteosclerosis and Paget’s disease etc.^11,12 The use of systemic antibiotic prophylaxis for the prevention of AO has been reported.^13-18 Various preventive local drugs, steroids and medications have been studied which includes amoxicillin paste, methylprednisolone and dexamethasone.^19-22 Chlorhexidine (CHX) is an antibacterial agent with established efficacy in dentistry.^13,17,23-25 Chlorhexidine is available in various concentrations and forms, such as the mouth rinse 0.12%, 0.2%, 1% and 2%; gel 0.2%.^12,21,26 CHX has been found effective against Staphylococcus and Streptococcus species which are the major source of dental infection.²⁷ The preventive role of CHX in alveolar osteitis in 3rd mandibular molar extractions is due to decreasing the bacterial load at the wound site.^28,29 Very little research has been done to study the effects of type of extraction and surgical flap design in generalized molars (1^st, 2^nd and 3^rd) extractions. Although the role of CHX is beneficial in mandibular 3rd molar surgeries, but its role for prevention of AO in generalized molars extractions  (1^st, 2^nd and 3^rd) in maxilla and mandible has not been studied. Therefore, the objective of our study was to study the effect of single dose of chlorhexidine on the frequency of AO.

METHODOLOGY

Sample

After approval from the Ethical Review Committee of the institution, a phase III (A phase which is designed to assess the effectiveness of the new interventional drug for its value in clinical practice),³⁰ double-blinded randomized clinical trial was conducted at the Oral Surgery Department of the Karachi Medical & Dental College, Karachi. The data collection was done from 1^st October 2013 to 31^st March 2014. An informed signed consent was taken from all the patients. The sample size of 250 was calculated by using the 24 % incidence of alveolar osteitis reported previously.²⁴ Unfortunately, the trial protocol was not registered at clinical trials.gov beforehand hence the data could not be released to the registry after the conduct of the study. Inclusion criteria: Patients aged between 18-65 years visiting the outpatient department for dental extraction of 1^st, 2^nd and 3^rd molar teeth in maxilla or mandible. Exclusion Criteria: Patients with history of bone grafts in molar region, smoking, current or past antibiotics therapy within 15 days, multiple extractions and any systemic disease or bleeding disorder were excluded.

Grouping and Randomization

The sample was randomized using block randomization into experimental (CHX) and control groups. The study was designed to have 80% power to detect 10% relative reduction of alveolar osteitis between the two groups (experimental and controls).¹² The dental extractions were performed by a trained dentist (X) adhering to a standardized extraction protocol. The 1.8 ml cartridge of 2% lidocaine plus 1:80,000  Epinephrine was used for extractions in this study. In mandibular molars, the inferior alveolar nerve block injection technique with lingual and long buccal nerve anesthesia was used. In maxillary molars, the facial and palatal infiltration technique was used.  The extractions were divided into surgical and nonsurgical extractions and recorded. The surgical extractions were divided in “envelope incision flap” and “envelope incision flap with buccal releasing incision”. The design of flaps used was documented by dentist X with every case. After extractions, the intervention group was applied with single dose of 10 ml quantity of 0.2% Chlorhexidine Gluconate gel (Clinica, Platinum, Pakistan) on sterile gauze. The control group received the placebo with gel consistency on the gauze. The patients were asked to bite on the gauze for 15 minutes and given standard postoperative instructions.

Alveolar Osteitis Diagnosis

The patients were recalled on 3^rd day post extraction and were assessed by a different dentist (Y). The pain was also measured on a Visual Analog Scale (VAS)¹⁹ ranging from 0-no pain to 10-worst pain imaginable. Any pain score above 5, in addition to clinical signs and symptoms based on Blum’s criteria4 was diagnosed with Alveolar Osteitis by dentist (Y). The outcome assessor (Y) was blinded of the group allocation (CHX versus placebo) done by intervention provider (X).

Data Analysis: The data was analyzed using SPSS 20.0 version for windows. The incidence of AO was compared with type of extraction, surgical flap design and the groups (experimental and control) using Chi-square test. Odds ratio was computed to determine the strength of association between AO and study group.The Yates corrected Chi square test was applied where the cell count in a cell was less than 5.The level of significance was set at 0.05.

RESULTS

There were a total of 253 patients; 41.9% were males and 58.1% females. The mean age of the patients was 36.65 years SD ±11yrs. Figure 1 represents the extraction site in Universal Tooth Numbering system. The mandibular

Figure 1: Extraction Site in Universal Tooth Numbering system

1^st molars were the most common teeth to be extracted with combine incidence of left and right side teeth making 37% of the total teeth extracted. No cases of hypersensitivity to intra-socket placement of CHX gel were reported in this study. The Table 1 represents the comparison of type of

Table 1: Association between type of extraction and alveolar osteitis

extraction with incidence of alveolar osteitis. The majority of teeth were simple extractions with 75.5% of total cases. Only 24.5 % required surgical flap procedures for extractions. The surgical extractions had an incidence of

38.7% of alveolar osteitis, whereas, the simple non-surgical extraction had only 3.1% incidence. The Chi-square test was used to establish a relationship and was found significant (p=0.001).

Table 2 and Figure 2 represent the comparison of type

Figure 2: Comparison of surgical flap for alveolar osteitis incidence

Table 2. Association between Surgical Flap and Alveolar Osteitis

Chi square test was applied at 0.05 level of significance of surgical flap with the incidence of alveolar osteitis. The group in which envelope flap with releasing incision was performed had highest incidence of alveolar osteitis (67.74%). This decreased in envelope incision and nonsurgical extractions. The Chi-square test followed by Yates correction was applied to establish a statistical relationship between the two variables and was found significant (p=0.001). Table 3 and Figure 3 represent the comparison between

Figure 3. Comparison of incidence of alveolar osteitis in the two study groups

Table 3. Association between type of group and alveolar osteitis

types of gel group with the incidence of alveolar osteitis. A total of 11.9% cases were diagnosed with alveolar osteitis. The single dose application of alveolar osteitis reduced the incidence of alveolar osteitis from 18% in the control group to only 5.4% in experimental group. The Chi-Square test was applied to establish a relationship with the incidence of alveolar osteitis and was found significant (p=0.001).

DISCUSSION

The pain in and around the extraction site, halitosis and lack of wound healing associated with Alveolar Osteitis (AO) makes it a serious dental extraction complication.³¹ Although, it can occur at any site, but 3^rd molar region had been focused predominantly in previous studies.^28,32,33 In this study we focused on all molar extractions (1^st, 2^nd and 3^rd) in maxilla and mandible. The level of surgical skills, trauma during extraction and invasiveness of surgical procedure for extraction has been studied to impact the incidence of AO in third molar.^34-37 Malkawi et al.⁶ said the postoperative complications can be predicted with presence of pericoronitis, longer traumatic surgery and surgical flaps with releasing incisions.  Haraji, et al.¹⁰ found that modified triangular flap decreases the incidence of AO and expedited healing post-surgery. Goldsmith et al.⁹ found pedicle flap had no incidence of AO, as compared to five cases in envelope flap. All the mentioned studies had relatively small sample size and focused on mandibular 3^rd molar region. In this study, the incidence of AO in surgical extraction was 35.6% more than non-surgical extraction. There is a debate about the use of conservative dental extraction approach for ridge preservation which results in rapid wound healing and may be of a benefit during implant placement.^38-41  In this study, it was seen that in molar extraction cases, the surgical trauma involved with the most invasive flap design (envelope flap with buccal releasing incision) had the highest incidence of AO. The incidence of AO was found higher in a similar invasive modified triangular flap, but this was not proven statistically significant.⁴² In another study though, the modified triangular flap design reduced the incidence of AO.¹⁰ Both studies had a small sample size of less than 50. The role of Chlorhexidine gel (CHX) has shown positive results in preventing AO, especially in the cases of impacted 3^rd molarswhere the incidence of AO was reduced by as much as 70%.^28,43 But the side effects of use of Chlorhexidine gel in dentistry have been questioned as well.^16,44 Although no cases of hypersensitivity to intra-socket placement of CHX gel were reported in this study, but several case reports are now becoming available reportingboth type I and type IV hypersensitivity in topically applied CHX.^45,46 Incidence of AO in routine dental extractions varies from 0.5-5% in literature.^11,47 In extractions of impacted 3^rd molars the incidence varies from 1%-30%.^3,48,49 In this study the incidence of alveolar osteitis was found to be 5.78% in experimental group and 22.54% in control group with a cumulative incidence of 11.85%. Several methods have been proposed to prevent AO such as intra-socket placement of antibiotics (Metronidazole, Clindamycin) in addition to topical CHX.⁵⁰

The recommended methods of use include CHX preoperative oral rinses continuing for 7 days postoperatively to single intraoral gel application; we opted for single intra-alveolar gel application rather than other topical methods in order to reduce the chance of protocol violation bias by the patients.¹³ Furthermore it has also been seen that using gel rather than CHX rinse was better in preventing AO.²⁵ Lagares et al.⁵¹ in his pilot study on third molar extractions had followed the same bioadhesive gel placement protocol as in our study and found a difference in the incidence dry socket but was not able to show statistically significant difference between the experimental and control group because of small sample size.⁵¹ In another study done in Pakistan, Babar et also found significant difference between control group and CHX bioadhesive gel use (p=0.017).⁵² In this study we found a highly significant difference in the incidence of AO between the CHX gel group and control group (p=0.001). The role of Chlorhexidine in the prevention of AO can be attributed to its antibacterial effect against the bacteria which causes fibrinolysis in the alveolar socket after extraction.²⁴ The use of Chlorhexidine in the prevention of Alveolar Osteitis in generalized molars (1^st, 2^nd and 3^rd) in maxilla and mandible is emphasized. The limitation of this study is the focus on molar region only. Further research needs to be done to address the effects of Chlorhexidine gel in all teeth extractions.

CONCLUSIONS

Within the limitations of this study, the incidence of alveolar osteitis in all molars (1^st, 2^nd and 3^rd) extractions was relatively increased when the type of extraction was surgical, invasive flap design (p=0.001) was adopted and CHX gel was not used (odds ratio 3.9). Single application of CHX gel after molars (1^st, 2^nd and 3^rd)  extractions significantly reduces the incidence of alveolar osteitis(p=0.001). Therefore, application of chlorhexidine in generalized molars (1^st, 2^nd and 3^rd)  extraction in maxilla and mandible is recommended.

Authors’ contributions:

MAK provided the intervention to the trial subjects, SB did outcome assessment of the study participants, FRK carried out statistical analysis and methodology supervision, FU critically reviewed the manuscript for publication, SMH provided clinical supervision and mentoring, TH served as data collection and entry.

Disclosure: The authors declare no conflicts of interests in the publication of this study. No financial benefits were obtained from the manufacturers of the products mentioned in this study.

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1. Oral Biology, University of Louisville, Louisville, Kentucky, USA.
2. Lecturer, Dentistry Liaquat College of Medicine and Dentistry Karachi, Pakistan
3. Assistant Professor, Dentistry Aga Khan University Karachi, Pakistan.
4. Assistant Professor, Dentistry Aga Khan University Karachi, Pakistan
5. Professor, Oral and Maxillofacial Surgery Karachi Medical & Dental College Karachi, Pakistan.
6. Karachi Medical & Dental College, Karachi, Pakistan.

Corresponding author: “Dr. Farhan Raza Khan” < farhan.raza@aku.edu >

Fazal Hakim Mian                                           

INTRODUCTION

Pakistan has an estimated population of 191.71 million comprising of 51% as female & 64.27 million in the age cohort of less than 14 years with two-third living in rural areas, spread over an area of 796,00 square kilometers stretches from Himalaya in the north to Arabian Sea in the south carrying literacy rate as 58%  area, is comprises of geographically in inaccessible sparsely populated Baluchistan, Southern Punjab, rural Sind, southern KP, hilly areas of AJK, Gilgit, Chitral& most part of northern districts of KP¹.

Three tier health system of primary, secondary & tertiary care is managed through 1142 tertiary & secondary care hospitals, almost 450 rural health centers and 9000 fist level care facilities. All the public sector hospital & most of the rural health manage oral health services through 15106 dental surgeons. Dental services are not available in 9000 fist level care facilities including basic health units, mother & child health centers, dispensaries, first aid post^1,2.

Telemedicine, healing at distance, providing clinical consultation & medical care through electronic data transfer in telecommunication technologies is evolving through telehealth & currently e-health covering wider subjects ranging from awareness, distant medical education, clinical consultation between patient-doctors & doctor-specialist, robot-managed bed care of patients and robot-performed distant surgical operations^3,4,5,6,7,8. Telemedicine or e-health is being practiced in Pakistan in some institution where m-health, provision of healthcare services through mobile phone technologies, is being practiced by Heat File International for critical poor patients⁹.

HOW TELEDENTISTRY IS APPLICABLE IN PAKISTAN?

Geographically sparspopulation of Pakistan with lack or shortage of qualified professionals in dentistry, shortage of dental specialist at secondary care hospitals and hardly available classified specialists in dentistry, arguably, make environment of Pakistan as most suitable for establishment of teledentistry. Making it priority in policy design & overcoming barriers in decision making process is considered difficult. Strong advocacy by professionals in the field, support by academia & promotion by intellectuals are the minimum requirements.

Fastness, Access & Efficiency are the basic arguments for provision of dental care through teledentistry but first appointment for consultation or care is documented taking longer than routine practices subject to availability of oral health services. Ambitiousness in the subject needs to be avoided. Keeping apart the first visit, teledentistry is fast, accessible & easily available^5,6,10,11.

Cost efficiency is argued negative while including investment in the technology, installation and management by addition of skilled professional. Capital investment for implementation is of course additional burden but cost for the patient is the minimum most. Once installed, ordinary trained dental profession can make teledentistry run with all ease^12,13.

Convenience & comfort in teledentistry toward patients suffering from pain of dental diseases at the farthest distances where there is no skilled person available carry no comparison^6,12,13.

Payments & reimbursements in teledentistry are the major legal drawbacks toward patients as well as toward professionals. Accounting mechanism for reimbursement of public servants has to devise. National Health Insurance Program covering oral health being launched has to design their policies for payments & reimbursements to professional against provision of oral health through teledentistry10,11,14.

Factors for Implementation particularly issues concerning with maintenance of governance, administration of accountabilities, legal requirements, ethical consideration are the hardest subjects. Very little legislative arrangement in the subject are prevailing even most of the developed countries. Cyber managements are in the process of evolution & are being taken care with the passage of time10,11.

Emergencies & Referral are considered the most suitable through teledentistry particularly in the backdrop of shortage of facilities, services, qualified dental professionals, specialist consultation. Otherwise, the vacuum has to be filled by quackery, the abuse of health services6,10,11,15.

Triaging during Disasters, otherwise an ethical issue, by qualified professionals is the critical most of the subjects. Teledentistry, through a team of qualified professionals is the most feasible remedy during the odd & critical moment of decision making¹⁶.

Dental Education through teledentistry requires all possible efforts for inclusion of the subject as an optional subject in curricula of dental education having very little space available for addition of additional subject¹⁹.

Dental Hygiene in School Health through demonstration of documentaries, considered the most suitable & costeffective, needs much of considerations²⁰.

Limitation

Dependency on telecommunication technologies, trained dental professionals in the subject, resistance of dental professional, adaptation by population with literacy rate as 45% are some of the important limitation & barriers in initiation of teledentistry.

Moreover, teledentistry may be extremely effective in diagnosis and follow-ups but its application in actual execution of procedures of restorative dentistry, prosthetics, surgery and orthodontics are limited.

CONCLUSION

Fast, accessible & cost-effective teledentistry suites much in the health system of Pakistan with shortage of dental facilities & oral health services, lack of dental specialist at secondary care hospitals, second opinion of classified dental specialists, emergencies & referral and triaging during disasters. Designing policy priorities, the subject can be accommodated in development budget. National Health Insurance Program covering oral health needs to consider teledentistry as a valid subject not only for consultation & care but as wider subject in regards outlined above.

Author Contribution: FHM is the sole author and is responsible for the authenticity of the facts described in the manuscript. Disclosure: None disclosed

REFERENCES

1. Government of Pakistan: Finance Division; Pakistan Economic Survey 2014-15, Printing Corporation of Pakistan Press, Islamabad, 2015
2. Pakistan Medical & Dental Council: Statistics; http://www.pmdc.org.pk/Statistics/tabid/103/Default.aspx (accessed october 15 2015).
3. World Health Organization. Telemedicine: opportunities and developments in Member States: report on the second global survey on eHealth. World Health Organization, 2010.
4. Perednia, Douglas A., and Ace Allen. “Telemedicine technology and clinical applications.” JAMA 1995;273: 483-488.
5. Eysenbach, Gunther, and CONSORT-EHEALTH Group. CONSORT-EHEALTH: improving and standardizing evaluation reports of Web-based and mobile health interventions. J med Internet res 2011;13.
6. T Chen, Jung-Wei, et al. Teledentistry and its use in dental education. J Am Dent Assoc 2003;134: 342-346.
7. Center for Online Health Annual report 2009: http://www.uq.edu.au/coh/documents/annualreports/C Mian FH OH%20Annual%20Report%202009_LR.pdf , (accessed October 15 2015).
8. D’Annibale, Annibale, et al. Robotic and laparoscopic surgery for treatment of colorectal diseases. Dis colon rectum 2004;47:2162-2168.
9. Nishtar, S. Heartfile’s contribution to health systems strengthening in Pakistan. East Mediterranean Health J 2006;12:s38-s53.
10. Jampani, ND, Nutalapati R, Dontula BSK, Boyapati R. Applications of teledentistry: A literature review and update. J IntSocPrev Community Dent. 2011;1:37-44.
11. Daniel SJ, Wu L, Kumar S. Teledentistry: A systematic review of clinical outcomes, utilization and costs. J Dent Hyg. 2013;87:345-352.
12. Harrison L. Mescape medical new. 2012. Teledentistry I m p r o v e s T r e a t m e n t R a t e : http://www.medscape.com/viewarticle/763101, (accessed October 15 2015).
13. Fricton, J, Chen H. Using teledentistry to improve access to dental care for the underserved. Den Clin North Am 2009;53:537-548.
14. Government of Pakistan: Ministry of Planning, Development & Reforms; Public Investment Authorization Section, Islamabad, OM No.5(531)/PIA-IV/PC/2014 dated 18th May, 2015.
15. Bradley SM, Williams S, D’Cruz J, Vania A. Profiling the interest of general dental practitioners in West Yorkshire in using teledentistry to obtain advice from orthodontic consultants. Prim Dent Care 2007;14:117-122.
16. Summerfelt FF. Teledentistry-assisted, affiliated practice for dental hygienists: an innovative oral health workforce model. J den edu. 2011;75:733-742.
17. Ignatius E, Mäkelä K, Happonen RP, Perälä S. Teledentistry in dental specialist education in Finland. Journal of telemedicine and telecare. 2006;12:46-49.
18. Chen JW, Hobdell MH, Dunn K, Johnson KA, Zhang J. Teledentistry and its use in dental education. The Journal of the American Dental Association. 2003;134:342-46.
19. Pakistan Medical & Dental Council: Guidelines for Continuing Medical Education (CME)/ Continuing Dental Education (CDE): http://www.pmdc.org.pk/Portals/0/ guidelines%20cmd.pdf , (accessed October 15 2015)
20. Annual report on dental hygiene: http://www.rdhmag.com/articles/print/volume-34/issue11/columns/public-health/annual-report-on-dentalhygiene.html , (accessed October 15 2015)
21. Andre RH, Kudryk VL. Teledentistry and the future of dental practice. DentomaxillofacRadiol. 1999;28:6061.
22. Vassallo DJ, Swinfen P, Swinfen R, Wootton R. Experience with a low-cost telemedicine system in three developing countries. J telemed telecare. 2001;7:56-58.

1. Deputy Chief, Health Section, Planning Commission, Ministry of Planning, Development & Reforms, Government of Pakistan, Islamabad

Corresponding author: “Dr. Fazal Hakim Mian” < fhmdr56@yahoo.com >

Fahd Ahmed¹                                       BDS, MSc

Haroon Rashid^{2                                             BDS, MDSc}

Sadaf Farookhi^{3                                            BDS, MSc}

Vivek Verma^{4                                                   BDS, MSc}

Yuliya Mulyar^{5                                                BA}

Murai Khalifa^{6                                                BDS, DDS}

Zeeshan Sheikh7                                           Dip, Dh, BDS, MSc, PhD                 

INTRODUCTION TO SURFACE TREATMENTS OF IMPLANTS

In the past few decades, there has been a great increase in the number of dental implants being placed. It has been well established already that the success of dental implants is dependent on early as well as late osseointegration.¹ The surface topography and geometry of an implant are important for their long and short term clinical success. For implant fabrication, titanium is the material of choice^2,3 as it has a low density giving it a high-strength-to-weight ratio. For that reason, it can be effectively alloyed with other metals like vanadium (4%) and aluminum (6%) particularly.⁴ The strength of the alloy is increased by incorporating aluminum and vanadium, while acting as a scavenger, prevents corrosion.⁵

Surface modifications like passivation, anodization, ion-implantation and texturing are essential methods for making dental implants perform better in terms of physical and biological standpoint after implantation.^6,7 It is believed that surface treatments improve the bioactivity and the osseointegrative properties of Titanium.^8-10 Surface texturing can increase implant surface area by up to six times, thereby improving osseointegration10. Implants can also be coated with a variety of materials that can aid implantbone bonding.¹¹ Calcium phosphate-coated implants have been described in the literature which demonstrate early direct bone attachment to the hydroxyapatite surface and this  occursas quickly as one month post-operatively.¹² The aim of the current review is to discuss various implant surfaces and methods that could accelerate the osseointegration process of dental implants.

METHODS TO IMPROVE SURFACE ROUGHNESS OF IMPLANTS

Numerous reports in the literature have suggested that implant surface characterization affects the rate by which bio-mechanical fixation and osseointegration occurs.^13,14 There are three different levels of surface roughness which depend on macro-, micro- and nano-sized topographies. Reports have suggested that the early fixation rates and long-term mechanical stabilization of the prosthesis may be enhanced by a high degree of surface roughness as  compared to decreased roughness or smooth surfaces.^8,15-17 The surface roughness of dental implants can actually be created by subjecting the surfaces to various treatment methods. The methods of incorporating surface roughness are described in subsequent sections.

Figure 1: Various dental implant surface modification techniques.

PLASMA SPRAYING

This is a method in which powdered form of titanium is injected into a plasma torch at very high temperatures. These powdered particles that get condensed upon the surface of the substrate ultimately fuse together to form a thin film over the implant surface.⁸ Usually, the plasma sprayed film is of approximately ~30 µm thickness. The film provides roughness of about ~3-7 µm which also increases the surface area.⁸ The 3D topography results in an increase of the tensile strength at the implant-bone interface.¹⁸ Preclinical studies on mini pigs have shown faster bone formation around the roughened implant surfaces as compared to the implant surfaces that are smooth with an average roughness of about 0.2 µm.¹⁹ Prospective case series studying treatment outcomes of titanium plasma sprayed implants reported that 92% of implants showed less than 1mm of peri-implant bone loss over a period of 20 years.⁸

GRIT BLASTING

This is the process in which bombarding of the titanium surfaces is done using hard ceramic particles which are forced through nozzle by using compressed air at very high velocities.²⁰ This results in surfaces with varying degrees of roughness and the variance is dependent upon the sizes of ceramic particles used on the implant surfaces, the air pressure and hardness values of the actual implant surface itself .²¹ Commonest materials used as grit include alumina, calcium phosphate and titanium oxide. They are biocompatible and are believed to cause no interference with the osseointegration of titanium implants post operatively.^22,23

Titanium implant surfaces blasted with 25 µm titanium oxide particles result in a moderately rough surface of about 1-2 µm.^18,24 Studies have shown that those implants which have been grit blasted using titanium oxide show greater contact with the bone during osseointegration²⁴ and this has been further proven by comparing their levels of osseointegration with machined surfaces.^8,25 Clinical trials have also shown that these implants have a success rate of 97.6% at 5 years and 91.1% at 6 years after implantation.^24,26 A study model demonstrated by Wennerbergand Albrektssonet al. showed implants which have been grit blasted using titanium oxide or alumina have similar bone-implant contact as compared to smooth titanium implants, but with an increased biomechanical fixation.¹⁸ Also, the ability of an implant to withstand torque force increases with an increase in its surface roughness.⁸ Calcium phosphates i.e. hydroxyapatite and β-tricalcium phosphate and their mixtures have also been used to grit blast titanium implant surfaces.²³ Calcium phosphates are osteoconductive and biocompatible and have shown to be resorbable with time.^27-31 Calcium phosphate grit blasted implant surfaces have also been shown to achieve greater implant to bone contact as compared to those surfaces that have only been machined.³²

ACID ETCHING

Hydrochloric acid, hydrosulphuric acid, nitric acid and hydrofluoric acid are strong acids which have been used for roughening of titanium implant surfaces.^33,34 Micropits are with sizes ranging from 0.5 to 2 µm in diameter are produced over the surfaces and this results in an increase in the surface area.⁸ This also causes superior bone adhesion and thus, increases the rate of osseointegration.³⁵ The process of acid Etching is done by immersing the implant into a mixture of concentrated acids for a period of several minutes and then subjecting the implant surface to the process of heating above 100 °C³⁶ The process carried out at high temperatures produces micro porosities which are homogenous in nature that helps in better wettability, superior contact with the bone,  good fibrin attachment and enhanced osseointegration subsequently.³⁶ Other advantages include less contamination since no surface particles are produced, and better osteoblastic retention. The osseo-conductive process has been shown to get enhanced by the use of dual acid etching process that promotes  attachment of fibrin and osteogenic cells resulting in formation of the bone directly over the implant surface.³⁷ However; the use of acids also negatively affect the mechanical properties and thus, creating micro-cracks over the surfaces causing the reduction of fatigue resistance of the implant.⁸ It has been shown that commercially pure titanium with concentration of hydrofluoric acid 48% at 90 °C for 15 min to 8 hours results in high values of surface roughness and increases sub-surface hydrogen.³⁸ Sulphuric acid has been shown to produce more surface roughness than other acids like hydrochloric acid and nitric acid.³⁸ A study conducted in dogs found that implants having dual acid etched surfaces had higher torque to interface failure compared to implants with as-machined surfaces.³⁹

ANODIZATION

Micro or nano-porous surfaces can be created by the potentiostatic or galvanostatic anodization of titanium in acids such as hydrosulphuric acid, hydrophosphoric acid, nitric acid and hydrofluoric acid.⁴⁰ The process of anodization also causes an increase in the oxide layer thickness to more than 1000 nm over titanium surface .^41,42 Because the acids used in the electrolyte solution are strong, this oxide layer is dissolved and is also thickened in other areas. The dissolution is also responsible for generating micro or nano-pores on the titanium surface⁴³, creating a moderately rough surface that facilitates osteoblast cell adhesion.⁴⁴

Anodized surfaces display better bone reinforcement and the osseointegration taking place on such surfaces can be explained either because of the mechanical interlocking in the pores by bone growth or due to biochemical bonding.⁴² Certain chemicals like calcium, magnesium and phosphorous have been incorporated in surface oxide layer.⁴³ Another process called anodic spark deposition has been investigated for its role in enhancement of titanium biocompatibility. A comparison has been done between Anodized alkali treated (AAT) titanium with chemically etched surfaces (bio-rough) and machined implant surfaces.⁴³ The surfaces which were chemically etched showed improved surface morphologies and caused no chemical modifications over the titanium implants. However; those surfaces which were subjected to AAT, showed bioactive micro- and nano-porous Ca and PO₄ enriched titanium oxide layer having a crystalline anatase structure.⁴³ This structure has shown to encourage hydroxyapatite layer nucleation and enhances the deposition of Ca and PO₄. It has been shown in experiments that the AAT surfaces encouraged proliferation and adhesion of cells over a period of 2 weeks and may be used in achieving stable and faster osseointegration of endosseous dental implants.⁴⁶

CERAMIC COATINGS ON DENTAL IMPLANTS

Materials like bioceramics (calcium phosphates) can be used to modify surface of a dental implant.⁴⁷ Bioactive ceramic implants are inorganic materials and depending upon on the physico-chemical nature of coatings, this can accelerate the formation rate of bone implant interface and also increases its stability and strength. The use of ceramics for coating metallic implants that produce an ionic ceramic surface has been documented.⁴⁸ The materials can be plasma sprayed or may be coated on to an implant surface. However it is worth mentioning that ceramics are brittle in nature, having low tensile and compressive strength.¹⁰

HYDROXYAPATITE (HA)

Hydroxyapatite (HA) is a compound of calcium phosphate with a composition of Ca₁₀ (PO₄)₆ (OH)₂ and has a crystallographic structure. It has a space group of p63/m and has a hexagonal atomic arrangement. This space group shows a six-fold c-axis perpendicular to the three equivalent a-axes at angles of 120 degree to one another. Every building cell or unit contains Ca, PO₄ and OH groups with are densely packed with each other.¹⁰ The appearance of Ca ions is in a form of a triangle while the OH groups are at the corner positions and the phosphates tetrahedral show a helical arrangement. Fluoride and chloride ions can be used to substitute the OH group which may cause a change in properties like the morphology, solubility and lattice parameters without the change in hexagonal parameters. For example, substituting  the OH group with fluoride ions causes the contraction of the cell which in turn increases crystallinity and the size of the crystal.⁴⁹ This substitution results in less soluble and more stable structure.⁵⁰

METHODS OF SYNTHESIZING HYDROXYAPATITE

There are many ways by which hydroxyapatite can be synthesized. Following are the common methods [52]:

1. Wet Methods which include precipitation method, hydrothermal techniques and hydrolysis of calcium phosphate.
2. Solid state reactions.
3. Ultrasonic irradiation
4. Sol-gel method
5. Microwave irradiation
6. Chemical precipitation
7. Micro-emulsion.

Depending on the technique used, differing morphological, stoichiometrical and crystallized products be obtained and authors feel that it is beyond the scope of this article to review all preparation methods.

HYDROXYAPATITE COATINGS

Since hydroxyapatite has a porous structure and is similar to the inorganic structure of teeth and bones, is has been widely researched upon for its use as a coating over metallic implants.²¹ However, its bulk is quite brittle if compared with ceramics zirconia oxide and aluminium.⁴⁴ HA coatings help to provide early stabilization of the dental implant in the surrounding bone and thus significantly reducing the healing time so that the prosthetic implant component can be placed earlier. It increases the functional life of the prosthesis over the implant and also produces optimum tissue response⁵¹ so that when the breakdown of the coatings occur, there is no adverse reaction in tissues surrounding the implant. The dissolution rate of HA in both alkaline and neutral aqueous solutions is quite low.^31,51 It has been speculated that even thought there is disintegration of the released PO₄ and Ca ions around the implant area, negative effects on bone formation are minimum. However; HA could cause disruption of the passive oxide layer present on the titanium implant surface. This disruption in turn causes the release of metallic ions which is undesirable.⁵²

It is generally believed that larger the crystallinity of the HA coating, the greater would be the resistance to dissolution in vivo.⁵³ On the other hand, HA surface coatings which are amorphous in nature would demonstrate a substantially higher rates of dissolution.⁵⁴ 50% crytallinity of HA is thought to be ideal for dental implant coatings.⁵⁵ Literature has shown that HA coated implants demonstrate better implant to bone integration. The values have been compared and for HA coated implants, these range between 17.1% for 7 days to 75.9% for 3 months as compared to values for metallic titanium implants which range from 1.2% in 7 days to 45.7%in 3 months^19,56 Although HA coated implants show better torque resistance is short term, it has also been shown that after a period of 6 months, no significant difference in the integration between ceramic coated metallic implants than non-coated metallic implants is seen.⁵⁷ Also, it is worth mentioning that the coating of HA helps in creating an additional interface between the bone and implant surface  and this could be a potential reason for the failure.⁵⁸ The use of nano-crystalline HA powders for coating has been described in the literature having a number of beneficial properties i.e. improved sintering ability, increased surface area and better densification which helps to reduce the sintering temperature.^59,60

METHODS TO COAT IMPLANT SUBSTRATE WITH HYDROXYAPATITE

There are a variety of methods that can be employed to coat implants with HA. However, the minimal requirements of HA being used as dental implant coating are that the crystallinity should be 62 %, phase purity around 95% , density should be 2.98 g/cm³, Ca/P ratio should be 1.67-1.76 , shear strength should be more than 22MPa and tensile strength more than 50.8 MPa.⁶¹ Methods used to coat the titanium dental implants with calcium hydroxyapatite with their merits and demerits are presented in Table 1 and discussed in the following sections.

PLASMA SPRAYING

Plasma spraying has been used to create rough surfaces and can also be used to coat dental implants with HA. This technique has similarities to the procedure in which surface porosities are created. It involves the injection of the ceramic HA into the plasma torch at very high temperatures which is then projected on to the surfaces

of the implant.⁶³ The particles will then condense and fuse resulting in formation of a thin layer on the titanium surface. There is a variation in thickness of this layer and it ranges from a few microns to a few millimetres.⁸ Plasma spraying has an advantage that it is rapidly deposited and has low cost⁵⁸, leading to faster osteointegration and decreased healing time.²¹ As plasma spraying leads to mechanical bonding of Ca/P with the substrate, roughening of the substrate gives good mechanical interlocking⁶⁴, which allows for an extended functional life of the implant.⁸ Disadvantages related to plasma spraying include weak adhesion^9,21 the formation of the residual stresses which may be created at the interface between the substrate and the coating. Plasma spraying may not be considered a technique for smaller dental implants with complex designs⁶⁵as the coating may disintegrate if the implant is insertion into bone with increased density.⁸

BIOMIMETIC DEPOSITION

Biomimetic deposition method is done under lower temperaturesand the risk of the coating flaking off is minimized. It also allows bone like HA crystals with greater bioactivity to be formed.⁶⁶ Firstly, oxidization of the substrate is carried out in a furnace at 800°C for a period of 1 hour. The procedure is started at lower temperatures and is increased at a rate of 5 °C per min until a temperature of 800 °C is achieved. This is held constant for 1 hour and then allowed to cool down slowly. These plates are cleaned using an alkaline medium in an ultrasonic bath and are the substrates are then inserted in plastic tubes containing phosphate buffered saline (PBS) solution, for 7 days in an incubator at a temperature of 37 °C. This procedure will cause the HA particle deposition. It has been shown that those implants having layers of HA placed by the process of biomimetic deposition show better bone bonding and thus, enhanced osseointegration.^66-68

SPUTTERING TECHNIQUE

Sputtered coatings have been gaining popularity recently because of the problems associated with plasma spraying .^63,69 The sputtering of calcium phosphates and HA leads to better bone strength and superior rates of initial osseointegration.⁶³ This process results in the formation of a coating of uniform thickness on flat substrates and this forms a dense coating of 0.5-3 µm thick. The ratio of Ca/P at the surface material is between the range of 1.6-2.6 and this is because of the fact that phosphorous ions are weakly bound onto the surfaces.⁷⁰ In vivo studies have proven that calcium phosphate coatings which are sputtered showed superior  implant fixation and healing response as compared to those surfaces which are grit blasted.^63,71 Another study carried out on rat bone marrow stromal cells showed better osteoconductivity and biodegradability on titanium plates with sputtered HA coatings, as compared to surface-modified titanium.²²

ELECTROPHORETIC TECHNIQUE (EPD)

The technique has been conventionally used to deposit ceramics, glass, polymers and can also be used to deposit composites materials like chitosan and HA.⁷² The cell for the process of electrophoretic deposition includes a cathodic substrate which is centred between two parallel platinum counter electrodes. The voltage for electrophoretic deposition is usually 10 to 30 V⁷³ and the average length of the formed HA is 200 nm which is essentially needle shaped.⁷³ The main advantage of this process is that it allows the deposition of coatings that contain HA-chitosan composites andsilica-chitosan.⁷⁴ This process may be carried out at room temperature that thus, may allow codeposition of various materials.⁷⁵ Studies have found that EPD-HA coatings have higher corrosion resistance as compared to uncoated titanium and also greater adhesion strength than plasma sprayed HA coatings.⁷⁶

DEPOSITION BY ELECTROCHEMICAL PROCESS

Depositing of HA using the electrochemical ways has gained much popularity as it can be used to coat those metal substrates which are highly irregular. The process is done quickly and at low temperatures. The chemical composition and the thickness of the coatings can be controlled provided that there are adequate conditions present during the process.⁷⁷ The specimens are first wetground using an appropriate abrasive paper, polished and rinsed using acetone and then lastly washed with distilled water. The deposition is then carried out using a potentiostat/galvanostatic cathodic polarization. The substrate during the process is used as cathode and platinum plate is used as the counter electrode.⁶⁶ The polarization during the process is conducted from an open circuit voltage (-3.0V) at the rate of -0.6 V per hour. The specimen is rinsed in distilled water so that the residual electrolytes are removed and then allowed to dry for 24 hours. This technique results in greater amount of hydroxyl from reduction of water and forms HA coatings which are more crystalline in nature. Thecoatings  formed by the process describe above are resistant to high scratch load of about 20N.77,78

CONCLUSION

This paper has discussed surface modification of dental implants by incorporation of roughness and coatings. Clinical and preclinical investigations have demonstrated that the bone response to a dental implant is greatly influenced by the surface topography. However, increased surface roughness of titanium implants could have contributed towards peri-implant disease as well as an increase in ionic leakage. The various techniques described above may lead to different in vivo responses after implantation and could affect clinical success rates. It is not easy to do a comparison particularly because of variation in the techniques used for implant surface characterization. Further in-depth research, especially long-term studies are required before anything definitive can be determined.

Author Contribution:

FA performed original design of the manuscript and writing, HR did peer review of the manuscript, correction of typographical errors and critical analysis, YM, MK, VV and SF critically analysed the manuscript and gave final approval, ZS drafted images and tables and reviewed the manuscript. Disclosure: None disclosed

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1. Faculty of Dentistry, Division of Oral Health and Society, McGill University, Montreal, Quebec, Canada.
2. Faculty of Dentistry, Division of Prosthodontics, Ziauddin University, Karachi, Pakistan.
3. Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada.
4. Family Dental Clinic, Strathmore, Alberta, Canada.
5. Faculty of Dentistry, University of Toronto, Ontario, Canada.

Corresponding author: “Dr. Haroon Rashid” < drh.rashid@hotmail.com  >

Sharea Ijaz1                                      PhD

Ayyaz Ali Khan2                              PhD

INTRODUCTION

While it is heartening to see the improved aptitude for research in dentistry across the country in the recent past, there is always

room for improvement.

Presented below is a commentary based on observations in the recent dental research proposals, write ups, and publications of Pakistani origin. A few key issues are outlined and each issue is then followed up with suggestions for improvement. These are based on the review of and discussion on several (20) reports of recent dental research (2010 to 2015) that the authors came across as part of their work in the past year.

The sampled reports are not identified partly because negative comments may impact publication chances as well as the repute of the people involved, and partly because these problems are not limited to the selected sample reviewed. But the main reason is that the aim here is to suggest options for bringing improvement, not assigning blame.

METHODOLOGY

One major issue is the lack of a good and justified match between aim and the methods used to achieve that aim. It is surprising to see aims of assessing effectiveness of X method of care with a one-time questionnaire survey in all who received X, when at least a before after design is warranted, if not that with a concurrent control. Similarly, cross sectional design is often followed by a convenient case series sampling.

ETHICS

Another major problem is ethics or rather the lack there of. It has been seen that researchers’ ethical compass is not always in line with the norms adhered to in the international circles. The problems range from not understanding informed consent and inappropriate comparison groups to wanting to test treatments that either have no lab based evidence of effectiveness or that contain potentially harmful agents.

This is serious and there can never be justification enough for an ethics review board to overlook any compromises on the interest of the patient in the slightest. The review boards must incorporate regular training of its members and ensure consumer (patient) representation amongst themselves to safeguard the interest of the participants.

The lack of awareness of civic rights among the masses is further conducive to poor ethic al practices in the Pakistani context. However, we have a duty to impart enough information so that people can choose for themselves. This information provision is not limited to clinical trials but applies to all research involving humans. To correct this, medical ethics should be a major compulsory component in the pre-clinical years of the healthcare studies across the country. The Helsinki declaration should be taught. In addition, there is a need to develop consent rules, for example, who can give consent on behalf of an unconscious or under age patient in Pakistan, and in what order? The west has clear guidelines but since our social norms are different these may not always apply to us. These guidelines should be taught at dental colleges in preclinical years. Nevertheless, research sections of organizations such as Shaukat Khanum Hospital and Agha Khan University within the same country have managed to publish error free ethically appropriate research related to oral health.

So, it may be as simple as following their lead and learning from their processes.

LITERATURE APPRAISAL

Often there are citations used to validate a point that the cited paper didn’t make. As a non-English speaking people it is expected that researchers sometimes misunderstand, however, there must be checks in place at the beginning stages (proposal/ background) of a research project to prevent this. The role of a supervisor or internal referee is invaluable in preventing these errors.

Furthermore, courses and workshops on research interpretation are probably needed more than those on statistics that are all the rage. If one doesn’t understand the difference between odds and risk ratio in practical terms, what use is being able to calculate either? In a recent course for post graduate dental students,  none of the participants knew why odds ratios and not risk ratios were reported for the cancer studies. Neither could they differentiate between a reported RR 0.8 (95% CI 0.6 to 1.1) and RR 0.7 (96% CI 0.6 to 0.8), although some of them knew the definitions and formulae for calculation by heart.

Thus it is not about lack of statistical knowledge although it seems so. The issue is not having interpreted research by critical appraisal of papers.

SWEEPING STATEMENTS

There are few who understand the need to pin a strong statement with a strong reference outside of results section. Assertiveness may be a wonderful quality in practice but in quantitative scientific research writing it is not. One shouldn’t say X causes Y for one because most times X may only be a risk factor for Y.  Also, a statement of causal inference should cite a reference of a primary study that showed the causal effect.

Contrary statements are also seen. In one discussion, the authors first state that the prevalence was 8% for condition Z in Pakistan, and then state at the end of the same paragraph that the Z prevalence in Pakistan was found to be 48%. This could be presented more appropriately as a range that has been found in the country in different studies. Of course, what is further missing here is an argument as to why this variation is seen between two different studies (sample sizes, locations, populations, or outcomes studied). It should also be noted that Pakistan is diverse, so that an average value may only be true with large scale stratified surveys. So it is best to keep statements conservative.

EDITORIAL STANDARDS

All of the above issues could be weeded out at the editorial stage of a submitted report. The fact that these get published implies lax reviewing and editorial standards, even when neither can be concluded from a published report alone.

It is one thing to see incorrect language, where sentences don’t make sense sometimes. This can be fixed easily. One English literature graduate with an IELTS score 8 in reading hired for the journal’s copy editing should be enough. Of course resources need to be made available for such a position.

What is more disturbing is poor quality research sometimes getting published in even good quality local journals, possibly to fill space. The pressure to accept more papers on the editors of dental journals in Pakistan is understandable, but it does not exonerate them. The practice may even perpetuate the problem. Even if they cannot refuse publications, the editors can always be creative: instead of (or as complement to) making sections for reviews, original articles, and short communications the editorial board can decide to separate papers that fit international reporting guidelines such as CONSORT or STROBE.  An alternative is to make adherence to reporting guidance mandatory for submission thus putting the onus on the writer. These guidelines are available at http://www.equator-network.org/  along with other help.

INFERENCE

In essence there are two broad areas needing improvement in dental research: the conduct, and the presentation. The responsibility for better conduct lies mostly with the teaching institutions where most research happens, and for presentation it lies jointly with the researchers and journals.

WAY FORWARD

The problems noted above can be prevented and rooted out as outlined. It is hoped universities and journals find the suggestions useful, and that others in the field will come forward to suggest more solutions.

The ideal would be to take stock of all dental publications of the past decade to see trends and test the above observations. Such a project can identify solutions based on evidence but requires dedicated resources beyond the authors’ reach currently. What is imperative meanwhile is beginning a culture of critical appraisal of scientific literature within the dental colleges in the country in the form of journal clubs to enhance capacity for research and its interpretation.

Disclosure: Neither of the authors have any financial or other conflicts of interest to declare which could potentially influence their opinions. The work behind this commentary was part of the IADSR work load

REFERENCE

1. (http://www.wma.net/en/30publications/10policies/b3/)
2. (https://www.shaukatkhanum.org.pk/research.html)
3. (http://www.aku.edu/research/Pages/home.aspx)
   

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   1.    Research and Academic Coordination, IADSR Lahore.

   2.   Director IADSR Lahore Pakistan.

   Corresponding author: “Dr. Sharea Ijaz ”  < sharea.ijaz@iadsr.edu.pk  > Received: 23 December 2015, Accepted: 23 December 2015