Health Services/Policy
Fluoridation and Risk of Fillings for Privately Insured Massachusetts Children Sam A. Merabi* Sam Merabi Pam R. Factor-Litvak Eric P. Tranby Brandon Frizzell Rebecca Preston
Water fluoridation aims to prevent childhood dental decay. We used a large private dental insurance database from 2016-2019 and merged it with community water fluoridation data and census data to conduct an ecological retrospective cohort study in Massachusetts examining whether community water fluoridation is associated with a reduction in two measures of dental decay: the ratio of dental fillings to exams and the risk of multiple fillings over the study period.
Linear regression and Poisson regression models were used, controlling for confounders (identified using a DAG) such as age, gender, topical fluoride use, dental sealants, and income. Even when excluding all other types of dental treatments, children in fluoridated areas had a significant lower ratio of dental fillings to exams, with a 3.4% reduction overall. Teenagers showed a greater reduction, with a 9.2% decrease compared to their peers in non-fluoridated areas. Poisson regression models reveal that the risk of requiring multiple fillings is significantly lower in fluoridated areas, with reductions ranging from 4.9% for the risk of more than one filling to 19.4% for the risk of more than eight fillings. Among teenagers, the protective effect was even more pronounced, with reductions reaching 26.8% for the risk of more than seven fillings and 25.4% for more than eight fillings. This pattern highlights the cumulative benefit of fluoridation in preventing dental decay.
We find fluoridation reduces the risk of dental fillings, a proxy measure of dental decay. These findings support the continued implementation of water fluoridation to prevent dental decay. They are particularly relevant for municipalities considering fluoridation, indicating potential cost savings and reduction in the severity of dental decay at a population level. Future study could extend through a longer longitudinal approach to include more years of tooth development with fluoride exposure or incorporation of prenatal exposure.