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Effect of fluoride in drinking water on dental caries and IQ in children.Abstract
The aim of this work was to evaluate the impact of fluoride exposure on the prevalence of dental caries and the intellectual ability of children.
Method: In this cross sectional study, 161 children from 9 to 10 years of age were evaluated. The concentration of fluoride in drinking water and urine was analyzed individually. Oral health status regarding dental caries and dental fluorosis was assessed. The intellectual ability of children was evaluated through the Raven’s Colored Progressive Matrices. In addition, variables such as diet, oral hygiene, body mass index, and socioeconomic status were included.
Results: There was a negative relationship between the DMFT index and the level of dental fluorosis. In the logistic regression analysis, a water fluoride exposure above 1.0 mg/L showed less risk of dental caries (OR = 0.41; p=0.025). Parental education level lower than high school raised significantly the risk of dental caries (OR = 2.81; p=0.036). No relationship was found between intellectual ability and
fluoride exposure variables such as, dental fluorosis, levels of fluoride in drinking water and urine, and exposure dose.
Conclusion: The results suggest that exposure to fluoride reduces the prevalence of dental caries, but no association was found to the intelligence of children.
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