Limited evidence for preventing childhood caries using fluoride supplements.

Data Sources: The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase, WHOLIS/PAHO/MEDCARIB/LILACS/BBO and Current Controlled Trials databases. Selected authors were contacted and the reference lists of articles searched.
Study Selection: Randomised or quasi-randomised controlled trials with a minimum of two years' follow up comparing fluoride supplements (tablets, drops, lozenges) with no fluoride supplement or with other preventive measures such as topical fluorides in children less than 16 years of age at the start were included.
Data Extraction and Synthesis: Eligibility, risk of bias assessment and data abstraction were conducted by two authors independently and in duplicate. Disagreements were resolved by consensus and by consulting a third author. The prevented fraction (PF), defined as the mean caries increment in controls minus mean caries increment in the treated group divided by mean caries increment in controls was used to evaluate efficacy. Random-effects meta-analysis was used where the data could be pooled. Heterogeneity was assessed and adverse effects recorded when reported.
Results: Eleven studies (involving 7196 children) were included. In permanent teeth, comparing fluoride supplements with no fluoride supplement, (three studies), supplement use was associated with a 24% (95% confidence interval (CI) 16 to 33%) reduction in decayed, missing and filled surfaces (DMFS). The effect of fluoride supplements was unclear on primary teeth. In one study, no caries-inhibiting effect was observed on deciduous teeth while in another study, the use of fluoride supplements was associated with a substantial reduction in caries increment.When fluoride supplements were compared with topical fluorides or with other preventive measures, there was no differential effect on permanent or deciduous teeth. The review found limited information on the adverse effects associated with the use of fluoride supplements.
Conclusions: This review suggests that the use of fluoride supplements is associated with a reduction in caries increment when compared with no fluoride supplement in permanent teeth. The effect of fluoride supplements was unclear on deciduous teeth. When compared with the administration of topical fluorides, no differential effect was observed. We rated 10 trials as being at unclear risk of bias and one at high risk of bias, and therefore the trials provide weak evidence about the efficacy of fluoride supplements.