|Year : 2017 | Volume
| Issue : 3 | Page : 198-202
Assessment of fluoride retention in jowar consuming population: A cross-sectional study
G Dhanu, R Shiny, R Havale, SP Shrutha
Department of Pedodontics and Preventive Dentistry, AME Dental College and Hospital, Raichur, Karnataka, India
|Date of Web Publication||31-Jul-2017|
Department of Pedodontics and Preventive Dentistry, AME Dental College and Hospital, Raichur, Karnataka
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Introduction: Dental fluorosis is considered as a serious public health problem in India. Water is usually the major source of fluoride exposure, but this is not the case always as exposure to local factors like diet can be important in some situations. Earlier studies have shown that jowar (a millet) consumption interacts with fluoride in the body and elevate fluorosis. Aim and Objective: To determine the association between jowar consumption and severity of dental fluorosis. Materials and Methods: Hundred schoolgoing children of 10–14 years old was selected by random sampling from Wadloor village. Dental fluorosis was measured in children by Thylstrup–Fejerskov index (1988). Twenty-four hours diet recall method was used to know the exposure to jowar of the children. A pretested questionnaire was given to mother or caretaker to record the jowar consumption. Spot urine samples of children were collected in plastic containers (20 ml) and brought to the laboratory in icebox. Ion selective electrode method was used to measure the fluoride level in urine samples of children. Results: On comparison of the quantity of jowar and fluorosis using Pearson Chi-square test, difference among variable was found out to be statistically significant (P = 0.013, P < 0.05). On comparison of quantity jowar consumption and urinary fluoride level using Pearson Chi-square test, the difference among variable was found statistically significant (P < 0.001). Conclusion: Jowar consuming population was positively associated with severity of dental fluorosis.
Keywords: Fluorosis, jowar, retention, risk factor
|How to cite this article:|
Dhanu G, Shiny R, Havale R, Shrutha S P. Assessment of fluoride retention in jowar consuming population: A cross-sectional study. J Indian Soc Pedod Prev Dent 2017;35:198-202
|How to cite this URL:|
Dhanu G, Shiny R, Havale R, Shrutha S P. Assessment of fluoride retention in jowar consuming population: A cross-sectional study. J Indian Soc Pedod Prev Dent [serial online] 2017 [cited 2019 Jul 17];35:198-202. Available from: http://www.jisppd.com/text.asp?2017/35/3/198/211852
| Introduction|| |
Fluoride is considered as an essential component in the prevention of caries. While the excess of fluoride can increase the risk of having fluorosis. Hence, we can describe the fluoride as “double edge sword” which means it can help or hinder simultaneously. Ingestion of the excess fluoride through water, dietary supplements, dentifrices enhances the risk of fluorosis. Along with this, various factors such as altitude of residence, food additives, malnutrition, composition of diet, and altered acid-base status will influence the risk of fluorosis.,,
Deposition of fluoride (F) in the hard tissue is influenced by several dietary factors such as protein, calcium, copper, zinc, and molybdenum among which only molybdenum has a positive correlation. Molybdenum will retain the fluoride in the body, and it is not excreted in urine., Plants and other foods can take up small amounts of fluoride from the air, soil, and water. One such plant is sorghum grain, which can retain some amount of elements from the soil and water.
In India, sorghum grain is known as jowar and is staple food in most of the areas. This sorghum grain grown in endemic F areas contained remarkably higher amount of molybdenum., Studies showed that molybdenum will retain fluoride during excretion resulting in fluorosis., Fluoride retention is increased in jowar based diet compared to other diet like rice., This may be considered as a risk factor contributing to the unexplained observation of high prevalence of severe dental fluorosis.
Hence, the present study was carried out to assess the correlation between jowar and fluorosis if any.
| Materials and Methods|| |
The study was conducted among school children of Wadloor village, Raichur district, Karnataka. Raichur district is one of the known fluoridated areas with water fluoride level of the Wadloor village ranging from 2 ppm to 7 ppm. It is a medium size village with total 315 families residing, has population of 1530 of which 783 are males while 747 are females as per population census 2011 and literacy rate of Wadloor village is 59.20% compared to 75.36% of Karnataka. Population of children with age 0–6 is 236 which is 15.42% of total population of village according to District Health Office Raichur.
The study population included school children aged between 10 and 14 years continuously residing in the Wadloor village since birth. Prior permission from higher authorities was sought before visiting the village. Written informed consents were obtained from parents and head of schools. Of the two government schools, one school was randomly selected. In the selected school, all the 100 school children aged between 10 and 14 years formed the sample of the present study.
Demographic variables such as age, gender, and father's occupation were recorded along with oral hygiene measures practiced by the school children. The dental examination was carried out for all hundred school children in the school settings under natural day lighting. WHO Type 3 examination method was used. A pretested questionnaire was developed for this study. A pretested interview schedule developed specifically for this study was used in the face-to-face interview. The food frequency questionnaire consisted of two components: a food list and a frequency response section for subjects to report the frequency of food consumption. The study assessed whether child consumed jowar as the staple food or not. Twenty-four hours diet chart was recorded in children to know their staple food and also the frequency of intake of jowar. Focusing on single day intake mainly regarding consumption pattern of staple diet jowar only. The mother/caretaker was questioned regarding the jowar intake, frequency, form of jowar, and at what age it was introduced to children.
Thylstrup and Fejerskov (TF) index (1988) was used to assess and grade dental fluorosis. Each permanent tooth (buccal/labial surfaces) was graded in the selected children according to the above index, and the tooth getting the highest score was assigned for the individual. Erupted teeth with <2/3 of the crown or filled teeth were excluded. Mild degrees of dental fluorosis and nonfluoridated opacities was differentiated according to the criteria of Russell. Investigator was trained and calibrated before carrying out the examination. Inter-examiner reliability was found to be 0.8.
Urine samples of children were collected at the spot after dental examination in nonreactive plastic containers (20 ml). Hundred samples were collected and stored in ice box and brought to the laboratory. All the samples were analyzed on the same day for F content using ion selective electrode method, which was developed by Orion Research Incorporated Laboratories Products Group USA. The model used was Thermo Fisher Scientific Orion VERSASTAR.
The data were entered and processed using SPSS version 21.0 (IBM, Bengaluru, Karnataka, India).
Descriptive qualitative data were represented by proportions (%) and quantitative data by mean and standard deviation. The comparison of dependent and independent variables was done by Pearson Chi-square test. Intra-examiner reliability was checked using Kappa reliability test.
| Results|| |
Demographic characteristics of the population are given in [Table 1]. The population was divided into jowar consumers and nonjowar consumers. Majority of the population (75%) who consumed jowar exhibited fluorosis when compared to nonjowar consumers (25%). This observed difference was statistically significant with (P < 0.013) [Table 2]. On the assessment of urinary fluoride level among the school children, it was found that mean urinary fluoride level was higher (4.588 ± 1.70) among nonjowar group children when compared to jowar group (3.211 ± 1.28) children. These differences observed were statistically significant with (P < 0.05) [Table 3].
|Table 3: Comparison of urinary fluoride levels among jowar consumers and nonconsumers (cases and controls) in terms of (mean [standard deviation]) using unpaired t-test|
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In nonjowar group, 92% of the population had fluorosis with white opaque lines corresponding to the position of perikymata and in some cases a slight “snow capping” of incisal edges. In jowar group, 53.3% of the population had fluorosis with opaque white lines merging to form cloudy areas with snow capping, and the score was increasing that is 13.3% of the population exhibited a marked opacity, and parts of the surface of teeth was exposed to attrition. 4% of the population showed round pits of enamel and whole surface was opaque, 4% showed that small pits were frequently merging in opaque enamel to form bands, and 1.3% of the population showed loss of outermost enamel in irregular areas.
| Discussion|| |
The present study is a cross-sectional survey conducted based on “STROBE” guidelines. The location of study area, Raichur, Karnataka, has varied cultural and food practices of southern and northern parts of the state particularly with regard to the staple food: jowar, rice, wheat, and ragi (millet). The fluoride content of some food materials shows variations based on the content of water and soil on which they are grown. Like sorghum, banana, potatoes contains a considerable amount of fluoride. Likewise, fluoride level of sorghum can be markedly influenced by fluoride content in water.
Sorghum which is called as jowar in India is the fifth largest important cereals after wheat, maize, rice, and barley. In 2013, the worldwide production of jowar was 61.5 million metric tons, and the main producers are USA, Nigeria, Mexico, India and Ethopia. Sorghum has many nutritional value because of its contents such as proteins, vitamins, and minerals and considered as major source of energy nutrients. A wide variety of recipes are based on jowar like it is cooked like rice, fermented for beer production, cooked into flat bread or like porridge preparation. In our study, more of population consumed it in the form of roti (bread form). The child's mother or caretaker was interviewed for jowar consumption. This would naturally validate information on the dietary patterns of children over the years as they controlled the feeding practices of children in earlier days. Twenty-four hours diet recall would validate the food frequency questionnaire.
But besides, all these important nutritional values jowar can retain trace elements from soil and water which causes serious issues. A less known feature is its relationship with fluorine. This study is conducted in Wadloor village, Raichur district which is considered as endemic area of fluorosis and Raichur district is characterized by dryness for the major part of the year, and the crop grown in this area is jowar which usually grows in semi-arid environment.
In a study conducted in 1973 by Krishnamachari and Krishnaswamy found that the genu valgum, a clinical manifestation of bone deformation was more frequent in sorghum-eating populations. A study conducted by Janakiram et al. in Davangere showed that children whose staple food was jowar had a 2.67-fold higher chance of getting severe dental fluorosis compared others whose was rice. A study conducted in Western Uganda by Wandera et al. showed that sorghum which is a weaning food item along with millet had the highest concentrations of fluoride. Rwenyonyi et al. in Uganda found that there is a high prevalence of dental fluorosis with low-fluoride water, indicating the role of diet. Moreover, in our study also, it showed that jowar group is at higher risk of getting severe fluorosis than nonjowar group.
In our study, the majority of the parents' occupation was farming (46%), and majority of the children (55%) used tooth brush and toothpaste to clean their teeth. In our study, we have observed that the jowar group had increase in fluorosis that is the score of fluorosis were increasing when compared to nonjowar group. We used TF index (1988) to measure fluorosis as it is more sensitive and based on biologic aspects and the scores obtained might be due to the retention of fluoride in jowar group as in another study which showed that retention (42%) of fluoride by Jowar consumers was more compared to rice consumers. One more study showed that jowar has higher levels of molybdenum compared to other cereals , which interact with F excretion and helps in F retention.,, Urinary F excretion among jowar consumers was significantly lower than nonjowar consumers. Moreover, in our study, too urinary fluoride level was lower in jowar consuming population than in nonjowar group.
On comparison of the gender of sample population, there was no statistical significant results between male (51%) and female (49%) in this study. A study conducted by Mann et al. in 1987 showed that boys had severe dental fluorosis when compared to girls. This could be due to the outdoor activities and late formation of teeth among boys. A study conducted by Mascarenhas and Burt, 1998 about fluorosis risk from early exposure to fluoride toothpaste showed that fluorosis risk was higher in males than females. This might be due to teeth developing in males is little later than in females, and as such could show a higher risk of fluorosis when compared to females.
And to know the staple food, twenty-four diet chart was recorded in children. In nutritional studies, the food frequency questionnaire and 24-h recall method is the standard method of assessing the dietary intake. In a study conducted by Janakiram et al. also used food frequency questionnaire and 24 h diet chart and mothers were asked about the jowar consumption. The limitation of our study was that we collected the spot urine sample rather than 24 h which was more reliable.
The association of jowar consumption with the severity of dental fluorosis and skeletal fluorosis has been widely studied, but the earlier studies were unable to demonstrate any association. In our study, we used TF index which is sensitive approach to assess fluorosis. In children, fluorosis develops when excess fluoride is ingested during the development of permanant teeth during 11 months to 8 years  so if we know the risk of jowar we can prevent severe fluorosis in children in endemic areas.
The study was conducted meticulously on children residing in areas with high fluoride content in drinking water. A sincere attempt has been done to record the information based on strict epidemiological principles. Although the study seems to have good internal validity, it is further recommended to conduct similar studies involving both children and adults residing in high fluoride belt. Valid conclusions and extraporations of results to external population can be done by future studies.
| Conclusion|| |
In these communities, health education and awareness are been done and the children are educated about the diet and uptake of milk and other essential vitamins and minerals, and as their drinking water source was from borewell they are educated to drink water available from river. The results of this study invite further study to find the process that describes the relation between jowar consumption and severe fluorosis.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3]