A meta-analysis of clinical studies on the caries-inhibiting effect of chlorhexidine treatment.

A meta-analysis was performed on published data on the caries-inhibiting effect of chlorhexidine treatment. The results of the various studies are difficult to evaluate because of various treatment procedures, dissimilar features of participants, and different presentations of study results. A meta-analysis provides a more structured approach than the traditional review, due to systematic analysis and numerical processing of the available information. The objectives of this meta-analysis were: (1) to assess a more accurate estimate of the caries-inhibiting effect of chlorhexidine treatment than provided by individual studies, and (2) to explore factors potentially modifying the effect of chlorhexidine treatment in caries prevention, i.e., the application method, application frequency, target population, the fluoride regime, and caries criteria. Caries reduction was expressed by the prevented fraction, indicating the percentage reduction of caries incidence in the chlorhexidine group. For all prevented fractions, 95% confidence intervals were calculated. The overall caries-inhibiting effect of the chlorhexidine treatment studies was 46% (95% CI = 35% - 57%). Multiple-regression analysis showed no significant influence on the prevented fractions for the variables "application method", "application frequency", "caries risk", "fluoride regime", "caries diagnosis", and "tooth surface".