Effectiveness of chlorhexidine-thymol varnish for caries reduction in permanent first molars of 6-7-year-old children: 24-month clinical trial.

OBJECTIVES To determine the effect of chlorhexidine varnish on the prevention of caries in permanent first molars. METHODS Two groups of 6-7-year-old school children were followed up in a clinical trial, a group of 86 children whose teeth were treated with a chlorhexidine-thymol varnish (Cervitec) and a control group of 95 children. The varnish was reapplied every 3 months and the caries increments were compared at 24 months. RESULTS The DFS (decayed and filled surfaces in permanent first molars) increment in the control group (mean = 1.85; SD = 2.27) was higher than in the test group (mean = 0.95; SD = 1.38), resulting in a 48.6% caries reduction. This difference was statistically significant (P = 0.032). CONCLUSIONS Chlorhexidine-thymol varnish is effective in preventing caries in permanent first molars.