Benefits of topical fluorides firmly established.

Abstract

Data sources The Cochrane Oral Health Group’s Trials Register the Cochrane Centre Register of Controlled Trials (CENTRAL), Medline, EMbase, SciSearch, Social SciSearch (ISTP Index to Scientific and Technical Proceedings), Biosis, CINAHL (Cumulative Index to Nursing and Allied Health Literature), ERIC (Educational Resources Information Centre) define, Dissertation Abstracts and LILACS/BBO (Latin American and Caribbean Health Science Information Database), databases were used, along with searches by hand of relevant journals and the reference lists of included articles. Selected authors and manufacturers were also contacted. Study selection Randomised or quasi-randomised controlled trials were chosen that had blind outcome assessment and compared fluoride varnish, gel, mouthrinse or toothpaste with placebo or no treatment in children aged up to 16 years over at least 1 year. The main outcome was caries increment measured by the change in decayed, missing and filled tooth surfaces [D(M)FS]. Data extraction and synthesis Inclusion decisions, quality assessment and data extraction were duplicated in a random sample of one-third of studies, and consensus was achieved by discussion or a third party. Authors were contacted for missing data. The primary measure of effect was the prevented fraction (PF), that is, the difference in mean caries increments between the treatment and control groups expressed as a percentage of the mean increment in the control group. Random-effects meta-analyses were performed where data could be pooled. Potential sources of heterogeneity were examined in random-effects metaregression analyses. Results Of the 144 studies included, 133 contributed data for meta-analysis (involving 65 169 children). The D(M)FS pooled PF estimate was 26% (95% confidence interval (CI), 24–29%; P<0.0001). There was substantial heterogeneity, which was confirmed statistically (P<0.0001), but the direction of effect was consistent. The effect of topical fluoride varied according to type of control group used, type of TFT, mode/setting of TFT use, initial caries levels and intensity of TFT application, but was not influenced by exposure to water fluoridation or other fluoride sources. The mean D(M)FS PF was on average 14% (95% CI, 5–23%; P=0.002) higher in non-placebo controlled trials, and likewise was 14% (95% CI, 2–26%; P=0.25) higher in fluoride varnish trials compared with all others. It was 10% lower (95% CI, −17 to −3%; P=0.003), in trials of unsupervised home use compared with self-applied supervised and operator-applied TFT. There was a 0.7% increase in the PF per unit increase in baseline caries (95% CI, 0.2–1.2%; P=0.004). The numbers needed to treat (NNT) in deciduous and permanent teeth are shown in Table 1 and pooled estimates of the treatment effects of different types of TFT in Table 2. Conclusions The benefits of topical fluorides have been firmly established on a sizeable body of evidence from randomised controlled trials. Although the formal examination of sources of heterogeneity between studies has been important in the overall conclusions reached, these should be interpreted with caution. No definite conclusions about any adverse effects that might result from the use of topical fluorides could be reached because such data from the trials are scarce.