COMPARISON OF THE EFFICACY OF 3 DIFFERENT CHLORHEXIDINE PREPARATIONS IN DECREASING THE LEVELS OF MUTANS STREPTOCOCCI IN SALIVA AND INTERDENTAL PLAQUE

The aim of the present study was to evaluate and compare the effects o f three different chlorhexidine (CHX)-containing preparations on mutan s streptococci (MS) levels in interdental plaque and whole saliva. Nin ety-three healthy school-children (8-10 years old) with high scores of salivary MS were selected by a screening procedure and randomised int o three equally sized groups. MS were enumerated at all mesial interde ntal sites of the first permanent molars with aid of a modified chairs ide technique. The patients were then treated three times within 2 wee ks with either a 1% CHX/thymol-containing varnish (group A) or a 1% CH X gel (group B), or they were subjected to daily supervised toothbrush ing with a 0.4% CHX dentifrice for I month (group C). Follow-up sample s of saliva and plaque from the interdental sites were collected 1 and 3 months after termination of treatment. A statistically significant reduction of MS levels in saliva and interdental plaque was found in a ll groups after 1 month. The CHX-containing dentifrice (group C) was t he most effective method in reducing MS levels in saliva, and a signif icantly stronger (p<0.05) suppression was found after 1 and 3 months w hen compared more effective than the varnish (group A). In the interde ntal plaque, the reduction of MS was less marked than in the saliva, a nd the three groups exhibited MS reductions of similar magnitude (20%) and duration, persisting up to 3 months. However a high proportion (a pproximately 50%) of all interdental sites were relatively unaffected by the treatments. In conclusion, our results suggest that the interde ntal MS colonisation was difficult to combat, irrespective of CHX prep aration and method, while the salivary levels were more easily affecte d. Daily tooth-brushing with a CHX-containing dentifrice was more effe ctive in reducing MS in saliva compared with the gel or varnish applic ations.