The effect of a chlorhexidine-fluoride varnish on mutans streptococci counts and laser fluorescence readings in occlusal fissures of permanent teeth: A split-mouth study.

OBJECTIVE

To evaluate the effect of a new chlorhexidine-fluoride varnish on mutans streptococci (MS) counts and laser fluorescence (LF) readings in fissures of permanent molars.

METHOD AND MATERIALS

The study group consisted of 57 healthy schoolchildren (7 to 14 yrs) that volunteered after informed consent. A double-blind split-mouth design was employed and 87 pairs of non-cavitated permanent molars were randomly assigned to treatments with either chlorhexidine-fluoride varnish (CHX-F) or chlorhexidine-thymol varnish (CHX-T, Cervitec Plus) as active control. The varnishes were topically applied at baseline and every sixth week throughout the 24-week study period. Endpoints were MS counts (CRT test) and occlusal LF readings (DIAGNOdent pen) registered regularly during follow-up.

RESULTS

At baseline, > 50% of the occlusal fissures harbored high MS counts (≥ 105 CFU), but a significant decrease (P < .05) was found after treatment with both varnishes. After 24 weeks, less than 5% exhibited high counts. There were no significant differences between the varnishes at any time point. The mean LF values were similar in both treatment groups at baseline, but a significant reduction (P < .05) was scored in the CHX-F group after 12 and 24 weeks. A similar reduction was found also in the CHX-T group after 24 weeks. No adverse events were reported.

CONCLUSION

There were no significant differences between the CHX-F and CHX-T varnishes in terms of MS suppression after four applications over 24 weeks. Both varnishes also reduced the LF readings significantly compared with baseline, but further long-term studies are needed to confirm a caries-preventive effect.