A study of prevalence and severity of dental fluorosis among school children in a Northern hilly state of India :Deepak Chauhan, Tripti Chauhan, Vinod Sachdev, Bimal C Kirtaniya, SRM Journal of Research in Dental Sciences

ORIGINAL ARTICLE
Year : 2012 | Volume : 3 | Issue : 3 | Page : 170--174

A study of prevalence and severity of dental fluorosis among school children in a Northern hilly state of India

Deepak Chauhan¹, Tripti Chauhan², Vinod Sachdev³, Bimal C Kirtaniya³,
¹ Department of Pedodontics and Preventive Dentistry, Himachal Dental College and Hospital, Shimla, Himachal Pradesh, India
² Department of Community Medicine, Indira Gandhi Medical College and Hospital, Shimla, Himachal Pradesh, India
³ Department of Pedodontics and Preventive Dentistry, Himachal Dental College, Sunder Nagar, Shimla, Himachal Pradesh, India

Correspondence Address:
Deepak Chauhan
Department of Pedodontics and Preventive Dentistry, H.P. Government Dental College, Shimla, Himachal Pradesh
India

Abstract

Background: Dental fluorosis is a major public health problem in 15 states of India. Himachal Pradesh has considerable amount of problem though not an endemic zone for dental fluorosis. Aims: To determine the prevalence and severity of dental fluorosis using Dean«SQ»s index among school going children of rural and urban areas. Settings and Design: A cross sectional study was conducted among the students in the age group of 5, 9 and 12 years from rural and urban areas of six district of Himachal Pradesh in the year 2009 to 2010. Materials and Methods: A total of 1,800 school children of both sexes from randomly selected schools were examined as per the WHO survey proforma to identify the presence of dental fluorosis and grade it using Dean«SQ»s index. Statistical Analysis Used: SPSS 15.0 was used. Data expressed as proportions and test applied was Chi-square test. Results: Out of these total 1,800 children, 973 were boys and 827 were girls. Of them, 612, 564 and 624 children belonged to the age groups of 5, 9 and 12 years, respectively. The overall prevalence of dental fluorosis was 4.1%. The prevalence ranged from highest 7% in district Shimla to lowest 1.7% in district Sirmour (P < 0.002). Dental fluorosis was equally distributed in rural and urban areas of six districts but was more common among girls than boys. The trend of increase in prevalence was observed with increase in age (P < 0.00002). Conclusions: A well-designed epidemiological study should be undertaken to evaluate the risk factors associated with the condition in the study region.

How to cite this article:
Chauhan D, Chauhan T, Sachdev V, Kirtaniya BC. A study of prevalence and severity of dental fluorosis among school children in a Northern hilly state of India .SRM J Res Dent Sci 2012;3:170-174

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Chauhan D, Chauhan T, Sachdev V, Kirtaniya BC. A study of prevalence and severity of dental fluorosis among school children in a Northern hilly state of India . SRM J Res Dent Sci [serial online] 2012 [cited 2023 Mar 26 ];3:170-174
Available from: https://www.srmjrds.in/text.asp?2012/3/3/170/107395

Full Text

Introduction

Dental fluorosis is one of the common but major public health problems in India. It is considered endemic in 15 states due to variable amount of fluoride content in ground water leading to an increase in the prevalence of fluorosis over the last 50 years. [1] Nearly 12 million of the 85 million tons of fluoride deposits on the earth's crust are found in India. [2],[3] About 62 million people in India suffer from dental, skeletal and non-skeletal fluorosis. Out of these; 6 million are children below the age of 14 years. [4]

In Rajasthan, highly rich fluoride groundwater, exceeding 10 mg/L, has been reported to exist in certain districts. So, fluorosis is also among the major dental issues. [5]

The occurrence of fluoride in drinking water has also been reported from Himachal Pradesh, which is a hilly state in the northern India. Though it is not an endemic area for fluorosis, yet sporadic cases of dental fluorosis had been reported from some districts. Fluoride is known for its toxic effect in drinking water and fluoride concentration in drinking water up to 1.0 mg/l is beneficial for the human but beyond 1.0 mg/l is considered to be deleterious to health and is the cause for dental and skeletal fluorosis. [6]

Dental fluorosis is the most convenient biomarker of exposure to fluoride and the evaluation of prevalence and severity of dental diseases are required for planning and implementing oral health programs in a given population. This is a well known fact, that the rural India has been most neglected in terms of oral health maintenance due to financial constraint and lack of education.

Moreover, not many studies have contributed to the facts on the magnitude of the problem of dental fluorosis in Himachal Pradesh. So, it becomes important to have the baseline data on the prevalence of dental fluorosis among children to foresee the possible risk factors for it, so that public awareness and knowledge to recognize this at the earliest, to prevent and control it at an initiation point. This study aimed to determine the prevalence and severity of dental fluorosis using Dean's index among school going children of rural and urban areas of the state.

Materials and Methods

This cross sectional study was conducted among the school going children in the age group of 5, 9 and 12 years from randomly selected public and private schools of rural and urban areas in six districts out of total 12 districts of Himachal Pradesh which were selected so as to represent different geophysical conditions and all four directions of the state, as well as the central regions-

Chamba (North)Sirmaur (South)Lahaul-Spiti (East)Una (West)Mandi (Central)Shimla - As it is the capital of the state and is having the maximum number of urban population, it was included in the study as the sixth district.

This study included school going children (N = 1800), of them, 612 children belonged to the age group of 5 years, 564 and 624 children belonged to the age groups of 9 and 12 years, respectively; from the schools of both urban and rural areas who were randomly selected from government and private schools of six districts of the state. From every district, 300 children were examined out of which 150 children were from the urban areas and 150 from the rural areas. Ethical permission was taken from institutional ethics committee before the start of the study. Informed consent was taken from the respective Principals of the school for examination of students. Data was collected through school records, interview and clinical examination. Thorough oral examination was performed and the presence of severity of dental fluorosis was recorded using Dean's Index (1942) on the WHO (1997) modified oral health assessment form. [7],[8],[9],[10] Dental fluorosis was recorded as per Dean's criteria. An index for assessment of dental fluorosis using a six point scale was developed by Trendley H. Dean. [7] Each tooth in the mouth was rated according to one of the six categories of Dean's index, and the individual's dental fluorosis score was arrived at based on the severest form recorded for two or more teeth.

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Results and Discussion

This study was first of its kind in Himachal Pradesh. The study included a total of 1,800 school children as study subjects in the age group of 5, 9, and 12 years studying in the schools located in the rural and urban areas of six district of Himachal Pradesh, which is a hilly state in Northern India. Out of these total 1,800 children, 973 were boys and 827 were girls. Of them, 612 children belonged to the age group of 5 years, 564 and 624 to the age groups of 9 years and 12 years, respectively [Table 1]. All the study subjects underwent thorough oral examination to determine the prevalence of dental fluorosis, to render dental care to the population residing in remote and difficult areas.{Table 1}

There had been studies on the fluoride levels in ground water in different states of India, which reported the level of fluoride concentration in water to be <0.2 to 6.5 ppm in Himachal Pradesh. [8]

In the present study, the overall prevalence of dental fluorosis was found to be 4.1% [Figure 1]. The proportion of students with very mild and mild dental fluorosis as per Dean's index was 1.2% and 1.4% respectively as shown in [Table 2]. This finding of low prevalence is attributed to less consumption of ground water for drinking purposes and supply of treated water for household consumption has increased as per revised guidelines of the Central Government. [9]{Table 2} {Figure 1}

This estimate in our study is very less as compared to other studies done in other states of India. The higher prevalence of 31.4% was reported from the Cuddalore district of Tamil Nadu, which is categorized as a fluorosis non-endemic area. [10] Similarly, the results of another study showed (29.4%) of dental fluorosis, which was experienced by children of schools in rural area of Lucknow. [11] However, in Haryana a very high prevalence of 92.7% was recorded among school children. [12] The present study did not show severe fluorosis in any of the students and only 0.2% of students had moderate fluorosis. Further, the revelations of the outcomes of the studies from across the world have shown the prevalence of dental fluorosis in Saudi Arabia and in Nairobi (Kenya) as high as 90% [13] and 76%, [14] respectively.

The present study reports the prevalence of 6.7% was found to be higher among the children in the age group of 12 years, (questionable 1%, very mild 2.1%, mild 2.6% and moderate 1.1%), followed by the prevalence of 4.4% among the children in the age group of 9 years (questionable 1.2%, very mild 1.2%, Mild 1.6% and moderate 0.4%). Among 5-year-olds, the prevalence of fluorosis was 1% (only questionable 0.8% and very mild form 0.2% of fluorosis) was noted. The difference between these age groups is highly significant P < 0.00002 [Table 2].

In this study, it has been observed that the prevalence of dental fluorosis had a linear relationship with the increasing age. This trend of increase in prevalence with increase in age is consistent with the findings of school children of rural school in Haryana and results of survey conducted by DCI among children in rural Tamil Nadu. [12],[15]

The important reasons that can explain this result is the placental barrier to transfer fluoride to the developing primary teeth where most of the mineralization takes place in the intrauterine phase and most of the teeth are deciduous in the age group of 5 years. [16] Moreover, the shorter duration of exposure to fluoride of the enamel formation of primary teeth. [17] Other reasons are that of the thinner enamel of primary teeth as compared to permanent teeth [17] and the fluoride gets absorbed more rapidly in growing foetus and are less available for primary teeth. [18] On the contrary, the greater physical size and activity and kind of nutrients intake lead to a higher intake of water, hence a higher prevalence in older age groups. [19]

The prevalence among girls was more 4.4% than boys 3.9% [Table 3]. Among girls (questionable 0s.8%, very mild 1.1%, mild 1.9%, Moderate 0.5% and severe form was noted to be nil whereas among boys (questionable 1.1%, very mild 1.3%, mild 0.9%, Moderate 0.4%) and severe form was again not presented by them. Not surprisingly, the difference between the findings of more prevalence of dental fluorosis among girls than boys is not statistically significant P<0.4219 [Table 4]. Moreover, this is consistent with the results of other studies conducted in Kerala, where higher prevalence was reported among girls. [1] On the contrary to the other studies, conducted among children of rural school in Haryana and Karnataka and Tamil Nadu where prevalence was reported more in boys than girls. [10],[20],[21]{Table 3} {Table 4}

In this study, the results have shown that the location of rural and urban have negligible impact on prevalence of dental fluorosis, the difference with location is not significant statistically P < 0.3873. Hence, dental fluorosis was equally distributed among the children from schools of both rural and urban areas of six districts [Table 5]. This can be explained from the fact that majority of population in Himachal Pradesh come from rural areas.

The district wise distribution of dental fluorosis shows that majority of school children 7% belonging to district Shimla presented with dental fluorosis followed by the children from district Chamba 6.7% and minimum 1.7% was reported from Sirmour. This difference among districts is statistically significant P < 0.002 [Table 6].{Table 5}{Table 6}

Limitations of the study

Fluorosis develops at the time of calcification of teeth from infancy and hence, the fluoride exposure during this period is of critical importance. This study being cross-sectional, the exact fluoride exposure during calcification of teeth cannot be measured now. Hence, it is presumed that the water sources are constant and not changed in last 10-12 years. The relationship with other risk factors needs to be studied.

Conclusion

This study establishes that there are cases of dental fluorosis in Himachal Pradesh; though the prevalence is low. The prevalence varied between the districts from 1.5% to 7%. It is recommended that the further study to be undertaken on fluoride intake from other sources like toothpaste, tea and diet in these areas because different culture, customs and dietary habits and patterns were observed during the study. Last but not the least; we would like to mention that fluoride intake varies with the variation in temperatures as our study area included areas with extreme temperature differences. The prevalence of dental fluorosis did not significantly differ in both sexes of students. Henceforth, it is highlighted that there is an urgent need to limit and control the dental problems as soon as possible because, Himachal Pradesh being a hilly state with difficult terrain resulted in some areas not yet been supplied with the treated or piped water, so people are forced to consume water from springs and other age old conventional sources of drinking waters.

Acknowledgement

We acknowledge cooperation of all the individuals who participated in the study.

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