Effects of fluoride tablets on caries and fluorosis occurrence among 6- to 9-year olds using fluoridated salt.

Objective: The aim of this retrospective cohort study was to investigate the association between the use of fluoride tablets among users of fluoridated salt and the occurrence of caries and fluorosis.

Materials And Methods: We examined 583 school children aged 6-9 years in Berlin, Germany for caries-status (modified defs > or = 1; d(3)-level) and fluorosis occurrence on central incisors (TSIF > or = 1). Parents completed questionnaires about several sociodemographic and oral health related factors of the previous years. To adjust for confounding, we used log-risk regression and estimated relative risks (RR) and 95% confidence intervals.

Results: The mean modified defs was 3.2 (SD = 5.9) and 58% children were caries-free. Twenty-two per cent of the children revealed mild fluorosis (TSIF 1 and 2). Length of fluoride tablet use was inversely associated (adjusted for age and SES) with caries-status: 2-4 years: RR = 0.8, 95%CI: 0.7-1.0, > or =5 years: RR = 0.5, 95%CI 0.3-0.7 (reference: 0-1 year use). This inverse association could mainly be observed in children who consumed fluoridated salt as well. Relative risks for mild fluorosis were 1.8 (95%CI: 1.1-2.9) and 2.7 (95%CI: 1.6-4.5) for fluoride tablet use of 2-4 years and > or =5 years, respectively compared with 0-1 year use.

Conclusions: Fluoride tablets seem to be effective in reducing the occurrence of caries in children with low caries levels in particular among those using fluoridated salt as well. However, fluoride tablets increase the occurrence of mild fluorosis in permanent incisors.