How effective are fluoride varnishes in preventing dental caries in children and adolescents?
The application of fluoride varnishes 2 to 4 times a year, either for the permanent or primary dentition, was associated with a substantial reduction in caries increment. This relative effect applied in populations with different levels of caries risk and exposure to other sources of fluoride. There was no evidence this relative effect was dependent on frequency of varnish application, length of follow-up, whether a prophylaxis was undertaken prior to application of the varnish, concentration of fluoride in the varnish, or use of a placebo rather than a no-treatment control. In the 13 trials that looked at children and adolescents with permanent teeth the review found that those treated with fluoride varnish experienced on average a 43% reduction in decayed, missing and filled tooth surfaces. In the 10 trials looking at the effect of fluoride varnish on first or baby teeth, the evidence suggested a 37% reduction in decayed, missing and filled tooth surfaces. There was little information concerning possible adverse effects or acceptability of treatment.
The quality of the evidence was assessed as moderate, as it included mainly high risk of bias studies, with considerable heterogeneity. As with many long-term trials involving children, there was an average of 19% attrition in the included trials which was not clearly accounted for but is likely to be due to movement of families out of the study area.
Dental caries is a highly prevalent chronic disease afflicting a significant proportion of the world population, including around 60% to 90% of school-aged children and the vast majority of adults.1 Topically applied fluoride varnishes have been used extensively as an operator-applied caries-preventive intervention for over 3 decades