Sodium fluoride and chlorhexidine effect in the inhibition of mutans streptococci in children with dental caries: a randomized, double-blind clinical trial.

OBJECTIVE: We aimed to compare the effect of sodium fluoride and chlorhexidine on salivary levels of mutans streptococci (MS), in a double-blind, randomized clinical trial. METHODS: Thirty-five healthy volunteers, aged 4-8 years, with at least one active carious lesion and no previous history of allergies were selected to participate in the study. A gel formulation containing either 1.23% sodium fluoride or 1% chlorhexidine was topically administered to the dentition every 24 h for 6 consecutive days. Salivary MS levels were measured at baseline (D1) and on the 6th (D6), 15th (D15), and 30th (D30) days. For microbiological analysis, Mitis Salivarius-Bacitracin agar medium was used. RESULTS: Difference between treatments was only verified on D6. On the last day of treatment 1% chlorhexidine gel was significantly more effective than fluoride (P = 0.0000). The use of sodium fluoride did not cause a statistically significant variation in salivary MS levels throughout the duration of the study. Following treatment, a subsequent increase in MS counts between D6 and D15 (P = 0.0001) was observed with chlorhexidine. CONCLUSION: A 6-day treatment with a 1% chlorhexidine gel was effective in reducing salivary MS; there was a significant MS increase once treatment was suspended. The use of 1.23% sodium fluoride under the same regimen was not able to reduce salivary MS levels. Our results suggest repeated treatment with 1% chlorhexidine as a means for maintaining low salivary MS levels in children with dental caries.

Antibacterial activity of the essential oil from Lippia aff. gracillis.

The essential oil of fresh leaves of Lippia aff. gracillis was analyzed by GC/MS and evaluated for its antibacterial effects. The results showed a moderate antibacterial activity and confirm the traditional uses of L. aff. gracillis.