Journal of Indian Association of Public Health Dentistry

ORIGINAL ARTICLE
Year
: 2022  |  Volume : 20  |  Issue : 2  |  Page : 159--167

Tooth loss and its risk factors among the young adults in the Kamrup (Metro) district of Assam: An epidemiological study


Jogeswar Barman1, Chandana Kalita2, Rupali Baruah3, Kalyani Choudhury4,  
1 Department of Prosthodontics, Regional Dental College, Guwahati, Assam, India
2 Department of Conservative Dentistry and Endodontics, GDC, Dibrugarh, Assam, India
3 Department of Community Medicine, Assam Medical College, GDC, Dibrugarh, Assam, India
4 Private Practice at My Dentist, Chandmari Colony, Guwahati, Assam, India

Correspondence Address:
Jogeswar Barman
Department of Prosthodontics, Regional Dental College, Guwahati - 781 032, Assam
India

Abstract

Background: Epidemiological studies on tooth loss, particularly in young adults (20–40 years), are very sparse, and it was probably not done in Assam and the whole of the northeast region of India. Aim: The aim of this study was to determine the role of the oral health determinants and analyze their potential risk on tooth mortality among the young adults of the rural and urban areas of Kamrup (Metro) district of Assam. Materials and Methodology: A total of 1540 young adults (20–40 years), 770 each from the urban and rural areas of the Kamrup (Metro) district, were selected using multistage cluster sampling. Oral health assessment was done by asking individual questionnaires and intraoral examinations. Collected data were statistically analyzed using Mann–Whitney U-test, Kruskal–Wallis test, and Pearson's Chi-square test at 0.05 significance level. Results: Overall 30.6% of the young adults demonstrated one or more tooth loss with no significant difference between rural (29.70%) and urban areas (31.40%). Tooth decay is the prime cause of tooth loss (23.7%), followed by tooth mobility (4.5%) and trauma (0.9%). The potential risk of tooth loss can significantly be influenced by education, occupation, consumption of sweet food, water sources, oral hygiene practices, smoking and chewing of different types of smokeless tobacco, paan-betel nuts, paan-masalas, and consumption of alcohol (P < 0.001). Conclusion: Tooth loss is a major oral health problem affecting >30% of the young adults. The potential risk of tooth loss due to major oral diseases can be influenced by education, occupation, sweet food, water sources, oral hygiene practices, bad oral habits, and alcohol consumption.



How to cite this article:
Barman J, Kalita C, Baruah R, Choudhury K. Tooth loss and its risk factors among the young adults in the Kamrup (Metro) district of Assam: An epidemiological study.J Indian Assoc Public Health Dent 2022;20:159-167


How to cite this URL:
Barman J, Kalita C, Baruah R, Choudhury K. Tooth loss and its risk factors among the young adults in the Kamrup (Metro) district of Assam: An epidemiological study. J Indian Assoc Public Health Dent [serial online] 2022 [cited 2024 Mar 29 ];20:159-167
Available from: https://journals.lww.com/aphd/pages/default.aspx/text.asp?2022/20/2/159/346879


Full Text



 Introduction



The study of dental epidemiology has been stimulated by its increasing concern in public health. Studies concerning epidemiology in dentistry have targeted many oral diseases and conditions, but the most worrying for their expression have been dental caries and periodontal disease, with particular epidemiological characteristics.[1],[2],[3]

Epidemiological studies can effectively determine the role of various factors of tooth loss and analyze their risk on tooth mortality of specific populations based on their location, races, or ethnic variability. Accordingly, results of these epidemiological studies help the policymakers to plan and strengthen oral health-care delivery systems for prevention and treatment of dental and oral diseases and promoting oral health care.

Young adults are considered as the principal workforce of a nation to contribute to productivity and GDP growth. Increased oral health burden, especially in this age group population, may hamper nations' progress. Epidemiological studies on tooth loss, particularly in young adults (20–40 years), are very sparse, and its nonexistence in Assam and the whole of the northeast encourages us to conduct this study to derive the baseline data on tooth loss in this age group population of Kamrup (M) district of Assam.

 Materials and Methods



The epidemiological survey was conducted within the territory of the Kamrup (Metropolitan) district that presently occupies an area of 995 km2, comprising 262.43 km2 urban and 692.57 km2 rural areas. This district consists of only one subdivision, i.e., Guwahati has six revenue circles which include 216 villages and 14 towns.

As per the census report, 2011, the metro district had a population of 1,253,938, of which males and females were 647,585 and 606,353, respectively. 82.70% of the total populations accounting for 1,037,011 people live in the urban areas of the district. The estimated young adult population within the 20–40-year age group is 511,799 comprising 256,248 males and 255,551 females.

A total of 1540 sample size was calculated by using the formula: N= [INSIDE:1] (considering prevalence [p] as 50% and d = 0.025 where z = 1.96). Multistage cluster design was used to select 770 samples from both the urban and rural areas. A pilot survey was also conducted on 300 young adults of the study areas before finalizing the study protocol which was approved by the Institutional Ethical Committee.

Inclusion criteria

Young adults (20–40 years) of urban and rural study areas having loss of one, more, or all the permanent teeth due to mechanical and pathological reasons.

Exclusion criteria

Tooth loss due to therapeutic extractions for orthodontic correction and prophylactic extraction of wisdom teeth that do not need replacementTooth loss due to partial or complete congenital anodontia.

Data collection

Oral health assessment of the selected subjects was done in two steps: collection of sociodemographic and oral and general health information by asking individual questionnaires followed by an intraoral examination. Individual questionnaires and intraoral examination (Microsoft Excel) record sheets with standard codes were prepared based on the Oral Health Assessment Form by World Health Organization (WHO) 2013. The socioeconomic condition (SEC) of the households was determined by using the modified BG Prasad socioeconomic classification 2018.[4] Questionnaires were prepared in English and translated into Assamese. Samples were divided into three age groups: Group 1: 20–26 years, Group 2: 27–33 years, and Group 3: 34–40 years.

The research scholar got trained and calibrated (kappa value = 0.90) to independently conduct the data collection procedure after getting written consent from the head of the households and selected subjects of the primary survey area during the year 2018–2019. The study data were tested for statistical normality using the Kolmogorov–Smirnov test which indicated that the data are statistically nonnormal (P < 0.001). So, the nonparametric testing methods: Mann–Whitney U-test, Kruskal–Wallis test, and Pearson's Chi-square test were used for inferential analysis of the data at 0.05 significance level.

 Results



The total sample population was 51.1% of males and 48.9% of females representing all religions, castes, and creeds. Based on their completed age in years, samples were distributed as follows: age group 1: 31.7%, age group 2: 30.9%, and age group 3: 37.4%. While 14.2% of the young adults of the district are illiterates, 15.4% of them have attained postgraduate education. Out of the total samples, 17.5% of them are unemployed and 18.5% of the samples are from below the poverty line [Figure 1].{Figure 1}

The overall tooth loss prevalence is found to be 30.6% with a slightly higher prevalence among the urban samples (31.40%) than their rural counterparts (29.70%). The overall mean number of tooth loss is 0.71 ± 1.54 (rural – 0.67 ± 1.58 and urban – 0.76 ± 1.49). However, the differences in prevalence and mean numbers of tooth loss with respect to place of residence and gender are not found statistically significant [Table 1].{Table 1}

It was evident that the overall prevalence of tooth loss and mean numbers of missing teeth do not increase with age. However, the tooth loss prevalence among the urban females of age group 3 was found to be significantly higher than their male counterparts (P = 0.023). The mean numbers of missing teeth were also found to be significantly increased with age among the female sample (P = 0.044) [Table 1].

Tooth decay was found to be the prime cause of tooth loss (23.7%), followed by tooth mobility (4.5%) and trauma (0.9%). With respect to the place of residence, the mean numbers of tooth loss due to tooth decay were found to be significantly higher (P = 0.004) in the urban populations (2.22 ± 1.54) than in the rural population (1.85 ± 1.33). The prevalence of tooth loss due to mobility was found to be significantly higher among rural females (P = 0.004) and with respect to trauma; tooth loss is significantly higher among the urban populations (P = 0.008) [Table 2].{Table 2}

Although the overall tooth loss prevalence and mean numbers of missing teeth are not significantly related to SEC, education and occupation of the sample population can significantly influence the tooth loss prevalence and mean numbers of missing teeth (P < 0.001) [Table 3]. Binary logistic regression analysis reveals that out of all sociodemographic factors considered, education and occupation reveal significant influence on tooth loss with P < 0.001. The odd ratios 0.770 and 0.699 in the reference groups “professional or honors” and “professionals,” respectively, indicate lower tooth loss among the highly educated group and the professional group compared to the lower education and occupation groups demonstrating negative regression coefficient −0.261 and −0.358, respectively, indicating that prevalence of tooth loss decreases as education and occupation levels increase [Table 3].{Table 3}

The prevalence and mean numbers of tooth loss are not found to be significantly related to dietary habits and staple food. However, they exhibited a highly significant relation (P < 0.001) with consumption of different types of sweet food, its combination, and sweet food taking frequency. The overall tooth loss also shows a significant relation with the household's drinking water sources (P = 0.003). In the rural areas, more populations use groundwater (deep tube well water – 41.9% and draw well water – 39.7%) than in the urban areas (deep tube well water – 30.3% and draw well water – 28.05%), whereas in the urban areas, 40.8% of the samples use municipality supply water against 10% in the rural areas. However, 8.3% of the rural samples use river water against 0.78% of the urban samples. The tooth loss both in prevalence and mean numbers are found to be significantly related to the water sources in the urban population (P < 0.001); but not in the rural population [Table 4].{Table 4}

The present study found a significant association of tooth loss with oral hygiene practices (P < 0.001) including tooth cleaning measures, type of tooth cleaning materials, timing of tooth cleaning, toothbrush changing frequency, types of toothpaste used, and mouth rinsing habits [Table 5]. Tooth loss was also found to be significantly related to oral habits of smoking, consumption of smokeless tobacco, betel nut, paan masala, and alcohol. The risk of tooth loss is increased by the frequency of smoking with a similar trend among the rural and urban subjects but projected the female smokers to potentially higher risk of tooth loss prevalence (100%) and significantly greater numbers of mean tooth loss (P < 0.001). Cent percent tooth loss prevalence and the highest numbers of mean tooth loss are reflected among the subjects who chew both khaini and ghutka [Table 6]. However, the binary logistic regression analysis reveals the strongest risk of tooth loss with non using of any tooth cleaning materials with regression coefficient 2.664 and odd ratio 14.348 (95% confidence interval) [Table 5] followed by the consumers of smokeless tobacco (khaini and ghutka) exhibiting a regression coefficient 1.820 and an odds ratio 6.173 as compared to nonconsumers [Table 6].{Table 5}{Table 6}

 Discussion



Tooth loss still remains to be a major public health problem worldwide with variable prevalence and distribution at national, regional, and local levels. The present study reveals overall tooth loss prevalence and mean number of tooth loss as 30.6% and 0.71 ± 1.54 with statistically insignificant but slightly higher values in the urban areas (31.40% and 0.76 ± 1.49) than in the rural areas (29.70% and 0.67 ± 1.58). The overall mean number of tooth loss found in the present study is comparable to the national value (2.0) and to the value reported for Assam (0.8) in the National Oral Health Survey, 2002–2003.[5] Similar to the present study, Hessari et al. reported 30% overall tooth loss prevalence among 18-year-old Iranians, but significantly higher prevalence was found in the rural areas.[6] In contrast, Jaleel et al. reported higher prevalence and mean numbers of tooth loss (57% and 4.2 ± 7.4) among adults aged 35–74 years in urban and rural areas of Davangere taluk, Karnataka.[7] They also reported a significant association between the place of residence and the mean number of tooth loss showing higher tooth loss (P < 0.01) in the rural areas (4.7 ± 7.8) as compared to the urban areas (3.5 ± 6.8). In conformity, Tomar et al.[8] also reported significantly higher mean tooth loss in the rural areas (1.4 ± 3) than in the urban areas (1 ± 2) in the 35–44-years age group population. They found significantly the lowest prevalence and mean numbers of tooth loss among this age group samples as compared to the older adults and elderly population. This was in agreement with Begum et al.[9] who had reported the highest and lowest tooth loss prevalence among the 65–74-years (96.18%) and 35–44-years (12.78%) age group samples, respectively. Hessari et al., however, in another epidemiological study in the 35–44-years age group population demonstrated a higher prevalence of tooth loss including 3% completely edentulous subjects, while Bonakhdarchian et al. reported 9% total edentulism.[10] In contrast, the present study, similar to George et al.[11] and the other studies conducted in Sri Lanka[12] and China,[13] could not find complete edentulism among the young adults.

Unlike most of the above studies and several other authors,[14],[15],[16],[17] the overall tooth loss prevalence and mean numbers of missing teeth in the present study do not demonstrate significant age and gender variations. However, the female samples show a significantly increasing trend in the mean number of tooth loss with age (P = 0.044) and a significantly higher tooth prevalence (P = 0.023) is seen among the urban females (39.6%) than the urban males (28%). In contrast, some studies have shown that females had less missing teeth than males[7],[9],[18] and others have shown female predominance.[19],[20] Although women are more self-conscious to look beautiful and maintain better dental and oral health,[21] overwhelmed responsibilities for making home and building their child's future along with official jobs for the servicewomen may prevent them from taking care of their dental health, especially during later young adulthood. The nonofficiating women, on the other hand, are financially dependent. Hence, the sociocultural behaviors and economic condition of the household may increase the confounding risk of tooth loss among these females.[22],[23],[24]

The results of the present study in terms of the reasons for tooth loss support the findings of Jaafar et al.[25] They also reported the highest loss between 21 and 30 years due to dental caries. Shah et al.[26] had also found the highest tooth loss prevalence 24% due to dental caries in adults aged 35–44 years and Shigli et al.[27] reported it to be 20.8%. The above findings are comparable to the present study which also confirms the worldwide trend[18],[25],[28],[29] that reported dental caries to be the most common reason for tooth loss followed by periodontal disease, except few studies[30],[31] that reported the opposite trend. While dental decay is a prime cause of tooth loss in all ages, tooth mortality due to tooth mobility tends to increase with aging and it may be more prevalent than caries after the age of 40 years.[25],[26] As the present study population was within 40 years of age, tooth loss due to tooth mobility was significantly less than it is caused by dental caries.

Higher mean numbers of tooth loss due to dental caries among the urban populations in this study may be attributed to the fact that they have more desire for refined and processed food. In contrast to Morita et al.,[15] tooth loss prevalence due to mobility in this study exhibited female predominance among rural population and supports the triad of factors (genetic, hormonal, and cultural influences) as explained by Lukacs[32] that may cause gender gap in tooth loss in South Asia.

In partial agreement with Barbato and Peres,[33] the present study demonstrated a grossly decreasing tooth loss trend with improved SEC, but the overall prevalence and mean numbers of tooth loss are not found statistically significant with SEC. This may be because of the fact that the household's monthly income is not expected to be influenced by the locality and gender variation. Yes, it may be mediated by sociocultural and psychosocial behaviors and environmental factors[34] which are again modulated by education and occupation of the family members of every household. Thus, in agreement with Urzua et al.[35] and Wennström et al.,[36] the present study reveals that the rate of tooth loss decreases as the education level increases and also supports some previous studies[37],[38] that related tooth loss to low education and low level of occupation.

Relatively few studies have evaluated the association of food habits with tooth loss. Sen et al.[21] found that 86% of the vegetarians had “tooth loss.” Jaleel et al. and Begum et al.[7],[9] also reported higher tooth loss among vegetarians as compared to those who were on a mixed diet. Although 94.5% of the nonvegetarian subjects in the present study demonstrated tooth loss, the prevalence and mean numbers of tooth loss are not found to be significantly related to dietary habit and staple food but maintain a highly significant relation with consumption of different types of sweet food, its combination, and frequency (P < 0.001). These findings maintain coherence with the studies presented by Sen et al.[21] and Jaleel et al.[7] The present study also agrees with the convincing evidence of collective human intervention, epidemiological, animal, and experimental studies that prove the association between the amount and frequency of free sugar intake and dental caries.[39],[40]

Besides food habits, fluoride content of drinking water sources can significantly influence the overall tooth loss prevalence (P < 0.001). The low fluoride content of surface water sources[41] than the groundwater sources[42] of the Kamrup (Metro) city probably can explain why the samples using untreated river water exhibited more prevalence and mean number of tooth loss than those who use municipality supply water and groundwater from draw well and deep tube well. The results of the present study reinforce the findings of a few previous studies that documented strong benefits of community water fluoridation exposure during various stages of life and its influence on adults' tooth loss.[43],[44],[45],[46]

With respect to oral hygiene practices, 87.9% of the subjects in this study brush their teeth regularly as compared to 44% by Jain et al.[47] and 91.8% by Ashok and Krishnaprasad.[48] In contrast, Gill et al.[49] reported that only 6% of the samples brush their teeth occasionally, as opposed to 58% of the children and 35% of the adults (35–44 years) who had never brushed their teeth, but tooth cleaning was mostly performed using chewstick (datun).[50] Al-Otaibi[51] also reported that 65% of the study (Makkah city) population use miswak chewing sticks. None of these studies related tooth loss with oral hygiene practices, but the binary logistic regression analysis in the present study reveals that among all the oral hygiene practice measures, subject not using any tooth cleaning materials carries >14 times higher risk of tooth loss. However, Bilagi et al.[52] could not record a significant risk among nonusers of tooth cleaning materials (P = 0.306). Other oral hygiene measures that show odds of highly significant risk (P < 0.001) for dental caries and/or periodontal disease-related tooth loss are types of toothpaste, toothbrush changing frequency, tooth cleaning way, tooth cleaning timing, and mouth rinsing after meal which is in support of Pandit and Javali.[53] In accordance with few previous studies,[7],[54] binary regression analysis in this study also projects daily sweet food taking frequency (5 times or more), types of sweet food, smoking habits and its frequency, paan masala, chewing of betel nut, smokeless tobacco, and alcohol consumption as the significant risk factors of tooth loss. However, longitudinal cohorts at the local, regional, and national level in this age group population are recommended to determine the cumulative risk of these factors on tooth loss during their later period of life.

 Conclusion



Tooth loss is a major oral health problem affecting >30% of the young adults of the Kamrup (Metro) district of Assam. The prevalence of tooth loss is not influenced by the age, gender, and locality, but the mean numbers of missing teeth may significantly increase with age in female subjects. Among other sociodemographic factors, education and occupation can significantly influence tooth loss.

Tooth decay is the prime reason for tooth loss, followed by tooth mobility, trauma, and other reasons related to systemic health. Staple foods do not carry a significant risk for tooth loss, but different types of sweet foods, its combination, and frequency can highly influence the prevalence and mean number of tooth loss. In addition, water sources may also affect the tooth retention profiles.

The potential risk of tooth loss increases with the frequency of tobacco consumption in smoking and smokeless form including betel nut and paan masala, projecting rural population to more risk, with propensity to rural females.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Mariri BP, Levy SM, Warren JJ, Bergus GR, Marshall TA, Broffitt B. Medically administered antibiotics, dietary habits, fluoride intake and dental caries experience in the primary dentition. Community Dent Oral Epidemiol 2003;31:40-51.
2Assaf AV, de Castro Meneghim M, Zanin L, Mialhe FL, Pereira AC, Ambrosano GM. Assessment of different methods for diagnosing dental caries in epidemiological surveys. Community Dent Oral Epidemiol 2004;32:418-25.
3Chandra A, Yadav OP, Narula S, Dutta A. Epidemiology of periodontal diseases in Indian population since last decade. J Int Soc Prev Community Dent 2016;6:91-6.
4Pandey VK, Pradeep A, Rakesh K. Modified BG prasads socio-economic classification-2018: The need of an update in the present scenario. Indian J Community Health 2018;30:82-4.
5Bali RK, Mathur VB, Talwar PP, Chanana HB. National oral Health Survey and Fluoride Mapping 2002-2003 India. New Delhi: Dental Council of India; 2004. p. 132.
6Hessari H, Vehkalahti MM, Eghbal MJ, Samadzadeh H, Murtomaa HT. Oral health and treatment needs among 18-year-old Iranians. Med Princ Pract 2008;17:302-7.
7Jaleel BF, Nagarajappa R, Mohapatra AK, Ramesh G. Risk indicators associated with tooth loss among Indian adults. Oral Health Dent Manag 2014;13:170-8.
8Tomar D, Menon I, Singh A, Tyagi U, Passi D, Goyal J. Comparative study of risk indicators associated with tooth loss among adult population in urban and rural areas of Muradnagar, Ghaziabad, Uttar Pradesh, India. J Family Med Prim Care 2019;8:528-34.
9Begum SK, Reddy VS, Krishna RV, Sudhir KM, Srinivasulu G, Ali SK. Tooth loss prevalence and risk indicators among adult people visiting community health centers in Nellore district, Andhra Pradesh: A cross-sectional study. J Indian Assoc Public Health Dent 2016;14:413.
10Bonakdarchian M, Ghorbanipour R, Majdzadeh F, Hojati T. Prevalence of edentulism among adults aged 35 years and over and associated factors in Yasooj. Journal of Isfahan Dental School 2011;7:101–4.
11George B, John J, Saravanan S, Arumugham IM. Prevalence of permanent tooth loss among children and adults in a suburban area of Chennai. Indian J Dent Res 2011;22:364.
12Ekanayaka A. Tooth mortality in plantation workers and residents in Sri Lanka. Community Dent Oral Epidemiol 1984;12:128-35.
13Luan WM, Baelum V, Chen X, Fejerskov O. Tooth mortality and prosthetic treatment patterns in urban and rural Chinese aged 20-80 years. Community Dent Oral Epidemiol 1989;17:221-6.
14Vignarajah S. Various reasons for permanent tooth extractions in a Caribbean population – Antigua. Int Dent J 1993;43:207-12.
15Morita M, Kimura T, Kanegae M, Ishikawa A, Watanabe T. Reasons for extraction of permanent teeth in Japan. Community Dent Oral Epidemiol 1994;22:303-6.
16Angelillo IF, Nobile CG, Pavia M. Survey of reasons for extraction of permanent teeth in Italy. Community Dent Oral Epidemiol 1996;24:336-40.
17Hull PS, Worthington HV, Clerehugh V, Tsirba R, Davies RM, Clarkson JE. The reasons for tooth extractions in adults and their validation. J Dent 1997;25:233-7.
18Susin C, Haas AN, Opermann RV, Albandar JM. Tooth loss in a young population from south Brazil. J Public Health Dent 2006;66:110-5.
19Reddy PS, Reddy AS, Jain AR. Tooth loss prevalence and risk indicators in an isolated population of Kadapa-South India. Am J Public Health 2014;2:221-5.
20Kida IA, Astrøm AN, Strand GV, Masalu JR. Clinical and socio-behavioral correlates of tooth loss: A study of older adults in Tanzania. BMC Oral Health 2006;6:5.
21Sen S, Balwani T, Sahu A, Parate N, Gehani A, Deolia S. Tooth loss and associated risk factors among rural population of Wardha district: A cross-sectional study. J Indian Assoc Public Health Dent 2018;16:11.
22Vaidya V, Partha G, Karmakar M. Gender differences in utilization of preventive care services in the United States. J Womens Health (Larchmt) 2012;21:140-5.
23Kaylor MB, Polivka BJ, Chaudry R, Salsberry P, Wee AG. Dental services utilization by women of childbearing age by socioeconomic status. J Community Health 2010;35:190-7.
24Russell SL, Gordon S, Lukacs JR, Kaste LM. Sex/Gender differences in tooth loss and edentulism: Historical perspectives, biological factors, and sociologic reasons. Dent Clin North Am 2013;57:317-37.
25Jaafar N, Razak IA, Nor GM. Trends in tooth loss due to caries and periodontal disease by tooth type. Singapore Dent J 1989;14:39-41.
26Shah A, Faldu M, Chowdhury S. Reasons for extractions of permanent teeth in western India: A prospective study. Int J Appl Dent Sci 2019;5:180-4.
27Shigli K, Hebbal M, Angadi GS. Relative contribution of caries and periodontal disease in adult tooth loss among patients reporting to the Institute of Dental Sciences, Belgaum, India. Gerodontology 2009;26:214-8.
28Cahen PM, Frank RM, Turlot JC. A survey of the reasons for dental extractions in France. J Dent Res 1985;64:1087-93.
29Petersen PE, Bourgeois D, Ogawa H, Estupinan-Day S, Ndiaye C. The global burden of oral diseases and risks to oral health. Bull World Health Organ 2005;83:661-9.
30Reich E, Hiller KA. Reasons for tooth extraction in the western states of Germany. Community Dent Oral Epidemiol 1993;21:379-83.
31Shah N. Oral health care system for elderly in India. Geriatr Gerontol Int 2004;4:S162-4.
32Lukacs JR. Gender differences in oral health in South Asia: Metadata imply multifactorial biological and cultural causes. Am J Hum Biol 2011;23:398-411.
33Barbato PR, Peres KG. Contextual socioeconomic determinants of tooth loss in adults and elderly: A systematic review. Rev Bras Epidemiol 2015;18:357-71.
34Haugejorden O, Klock KS, Astrøm AN, Skaret E, Trovik TA. Socio-economic inequality in the self-reported number of natural teeth among Norwegian adults – An analytical study. Community Dent Oral Epidemiol 2008;36:269-78.
35Urzua I, Mendoza C, Arteaga O, Rodríguez G, Cabello R, Faleiros S, et al. Dental caries prevalence and tooth loss in chilean adult population: First national dental examination survey. Int J Dent 2012;2012:810170.
36Wennström A, Ahlqwist M, Stenman U, Björkelund C, Hakeberg M. Trends in tooth loss in relation to socio-economic status among Swedish women, aged 38 and 50 years: Repeated cross-sectional surveys 1968-2004. BMC Oral Health 2013;13:63.
37Buchwald S, Kocher T, Biffar R, Harb A, Holtfreter B, Meisel P. Tooth loss and periodontitis by socio-economic status and inflammation in a longitudinal population-based study. J Clin Periodontol 2013;40:203-11.
38Ito K, Aida J, Wakaguri S, Takeuchi K, Noguchi Y, Osaka K. Socioeconomic inequalities in tooth loss among Japanese. In: Interface Oral Health Science 2011. Japan: Springer; 2012. p. 291-3.
39Moynihan P, Petersen PE. Diet, nutrition and the prevention of dental diseases. Public Health Nutr 2004;7:201-26.
40Hujoel PP, Lingström P. Nutrition, dental caries and periodontal disease: A narrative review. J Clin Periodontol 2017;44 Suppl 18:S79-84.
41Borah M, Das PK, Borthakur P, Basumatary P, Das D. An assessment of surface and ground water quality of some selected locations in Guwahati. Int J Appl Environ Sci 2020;15:93-108.
42Das B, Talukdar J, Sarma S, Gohain B, Dutta RK, Das HB, et al. Fluoride and other inorganic constituents in groundwater of Guwahati, Assam, India. Curr Sci 2003;85:657-61.
43Neidell M, Herzog K, Glied S. The association between community water fluoridation and adult tooth loss. Am J Public Health 2010;100:1980-5.
44National Research Council, Division on Earth and Life Studies, Board on Environmental Studies and Toxicology, Committee on Fluoride in Drinking Water. Fluoride in Drinking Water: A Scientific Review of EPA's Standards. Washington, DC: National Academies Press; 2007. p. 530.
45Griffin SO, Jones K, Tomar SL. An economic evaluation of community water fluoridation. J Public Health Dent 2001;61:78-86.
46Horowitz HS. The effectiveness of community water fluoridation in the United States. J Public Health Dent 1996;56:253-8.
47Jain N, Mitra D, Ashok KP, Dundappa J, Soni S, Ahmed S. Oral hygiene-awareness and practice among patients attending OPD at Vyas Dental College and Hospital, Jodhpur. J Indian Soc Periodontol 2012;16:524-8.
48Ashok VG, Krishnaprasad C. A study on oral hygiene among school children in a rural area of Tamilnadu. Int J Contemp Med Res 2016;3:2798-9.
49Gill M, Pal K, Gambhir RS. Oral hygiene practices, attitude, and access barriers to oral health among patients visiting a rural dental college in North India. J Dent Res Rev 2014;1:114.
50Varenne B, Petersen PE, Ouattara S. Oral health behaviour of children and adults in urban and rural areas of Burkina Faso, Africa. Int Dent J 2006;56:61-70.
51Al-Otaibi M. The miswak (chewing stick) and oral health. Studies on oral hygiene practices of urban Saudi Arabians. Swed Dent J Suppl 2004;167:2-75.
52Bilagi UR, Kalyanpur R, Shetty PJ. Tooth loss and tooth brushing practises among adults of Dharwad, India. J Evol Med Dent Sci 2019;8:1098.
53Pandit PV, Javali SB. Multiple logistic regression model to predict risk factors of oral health diseases. Rom Stat Rev 2012;5:1-14.
54Khazaei S, Keshteli AH, Feizi A, Savabi O, Adibi P. Epidemiology and risk factors of tooth loss among Iranian adults: Findings from a large community-based study. Biomed Res Int 2013;2013:786462.