- The red propolis extract inhibited Streptococcus spp. and L. casei.
- Propolis mouthwashes with fluoride exhibited cytotoxicity similar to chlorhexidine.
- Propolis mouthwashes tested decreased the growth of a cariogenic biofilm.
- Propolis + fluoride mouthwash showed antibiofilm effect similar to chlorhexidine.
OBJECTIVE: To evaluatein vitro the antibacterial activity, the antibiofilm effect and the cytotoxic potential of mouthwashes containing Brazilian red propolis with or without fluoride.
METHODS: The minimum inhibitory and bactericidal concentrations (MIC and MBC) against S. mutans, S. sanguinis, S. salivarius and L. casei were determined for RPE mouthwashes. A cariogenic biofilm with the aforementioned bacteria was formed over cellulose membrane disks (N = 30, 13 mm), which were submitted for 1 min to the following mouthwashes: plain mouthwash base; 0.05% NaF; 0.8% RPE; 0.8% RPE + 0.05% NaF and 0.12% chlorhexidine (CHX). The bacterial viability and the production of extracellular polysaccharide (EPS) were measured. Cytotoxic potential of the mouthwashes was also evaluated. For bacterial viability and EPS production, Mann-Withney and one-way ANOVA tests were performed followed by Tukey, with results considered significant when p?0.05.
RESULTS: MIC and MBC values of RPE mouthwashes ranged from 7.44 to 29.76 mg/mL and from 7.44 to 59.52 mg/mL, respectively, presenting better action against S. salivarius. RPE mouthwashes showed 44% of viable cells after 1?min of contact with fibroblasts. RPE (7.74) had the greatest reduction of viable total microorganisms and did not differ from the RPE + NaF (7.95) (p = 0.292). CHX (7.54) was the most effective in reducing Streptococcus spp, but did not differ from RPE (p = 0.521) and RPE + NaF (p = 0.238). There was no difference between the treatments regarding EPS production.
CONCLUSION: RPE and RPE + NaF mouthwash showed similar antibacterial activity, toxicity level and antibiofilm effect compared to CHX.