The Effect of Solutions Containing Extracts of Vochysia tucanorum Mart., Myrcia bellaCambess., Matricaria chamomilla L. and Malva sylvestris L. on Cariogenic Bacterial Species and Enamel Caries Development.

This study evaluated the effect of experimental solutions containing plant extracts on bacterial species and enamel caries prevention. Microcosm biofilm was produced from human saliva mixed with McBain saliva (0.2% sucrose) on bovine enamel for 5 days (3 days under anaerobiosis and 2 days under aerobiosis) at 37°C. From the 2nd day, the following treatments were applied (1 × 60 s/day): Vochysia tucanorum (10 mg/mL); Myrcia bella (5 mg/mL); Matricaria chamomilla (80 mg/mL); Malva sylvestris, fluoride, and xylitol (Malvatricin Plus®); 0.12% chlorhexidine (CHX, PerioGard®); and PBS (negative control). The medium pH was measured. Quantitative polymerase chain reaction was performed for the detection of Streptococcus mutans and Lactobacillus spp. Enamel demineralization was measured by spectral-domain optical coherence tomography. The data were compared by means of the Kruskal-Wallis/Dunn, two-way ANOVA/Bonferroni, and ANOVA/Tukey tests (p < 0.05). The pH decreased after sucrose exposure; only CHX reestablished pH >5.5 by the last day. CHX also eliminated Lactobacillusspp., but the other treatments did not differ significantly from PBS. Malvatricin Plus® and CHX eliminated S. mutans, but the other treatments did not differ from PBS. Similar results were seen concerning the reduction of lesion depth and reflectivity. The experimental natural-extract solutions were ineffective against cariogenic bacteria and in preventing the development of enamel caries.

Antibiofilm and anti-caries effects of an experimental mouth rinse containing Matricaria chamomilla L. extract under microcosm biofilm on enamel.

OBJECTIVE: This study evaluated the antibiofilm and anti-caries effects of an experimental mouth rinse containing aqueous extract of Matricaria chamomilla L. METHODS: Microcosm biofilm was produced on bovine enamel, from pooled human saliva mixed with McBain saliva, under 0.2 % sucrose exposure, for 5 days. The biofilm was daily treated using (1 mL/1 min): Vochysia tucanorum Mart. (2.5 mg/mL); Myrcia bella Cambess. (1.25 mg/mL); Matricaria chamomilla L. (20 mg/mL); Malva sylvestris (Malvatricin® Plus-Daudt); 0.12 % Chlorhexidine (PerioGard®-Palmolive, Positive control) and PBS (Negative control). The % dead bacteria, biofilm thickness, EPS biovolume, lactic acid concentration, the CFU counting (total microorganisms, Lactobacillus sp., total streptococci and Streptococcus mutans/S. sobrinus) were determined. Enamel demineralization was measured by TMR. RESULTS: All mouth rinses induced bacterial death compared to PBS (p < 0.0001). The biofilm thickness varied from 12 ±â€¯2 µm (chlorhexidine) to 18 ±â€¯2 µm (V. tucanorum) (ANOVA/Tukey, p < 0.0001). The EPS biovolume varied from 7(4)% (chlorhexidine) to 30(20)% (PBS) (Kruskal-Wallis/Dunn, p < 0.0001). The lactic acid production was reduced by M. sylvestris (1.1 ±â€¯0.2 g/L) and chlorhexidine (0.6 ±â€¯0.2 g/L) compared to PBS (2.6 ±â€¯1.3 g/L) (ANOVA, p < 0.0001). Malva sylvestris and chlorhexidine showed significant low CFU for total microorganisms, Lactobacillus sp. and total streptococci. Only chlorhexidine significantly reduced S. mutans/S. sobrinus. CFUs for total streptococci and Lactobacillus sp, were also significantly reduced by M. chamomilla L. Malva sylvestris (63.4 % of mineral loss reduction), chlorhexidine (47.4 %) and M. chamomilla L. (39.4 %) significantly reduced enamel demineralization compared to PBS (ANOVA/Tukey, p < 0.0001). CONCLUSION: M. chamomilla L. has lower antibiofilm action, but comparable anti-caries effect to those found for chlorhexidine, under this model. CLINICAL RELEVANCE: This study shows that the antibiofilm and anti-caries potential may vary between the commercial and experimental mouth rinses containing natural agents, with promising results for those containing Matricaria chamomilla L. and Malva Sylvestris.