Chlorhexidine varnish has caries-reducing potential

Abstract

A double-blind, randomised, placebo-controlled clinical trial was conducted. Children in the test group received 6-monthly applications of a 40% chlorhexidine varnish whereas children in the control group received a placebo varnish, over the course of 2 years. Clinical examination was undertaken at baseline and after 24 months by two calibrated dentists who did not know to which groups children were assigned. Decayed, missing, or primary filled molar surfaces (dmfs-molar) were monitored. At baseline, there was no significant difference between the mean dmfs-molar scores of the two groups (2.8 vs 2.6; P>0.05 ). After 2 years, 44 children (13%) were lost to follow-up, because some (n=31) had moved to other kindergartens, and some (n=13) objected to the taste of the varnish and refused to be examined. After 2 years, 290 children remained in the study, of whom 155 were in the test group and 135 were in the placebo group. The mean caries increment of the primary molars was 1.0 dmfs-molar in the test-group children and 1.6 dmfs-molar in the placebo group. The difference of 0.6 tooth surface equated to a 37.3% reduction in caries increment (number-needed-to-treat of 3), and was statistically significant (P 0.036; 95% confidence interval, 0.04-1.16). No side-effects (such as soft-tissue lesions and staining of teeth) were found at the 24-month examination. Six-monthly applications of chlorhexidine varnish were effective in reducing the incidence of dental caries in primary molars.