the antibacterial effect of sage extract (salvia officinalis) mouthwash against streptococcus mutans in dental plaque: a randomized clinical trial

background and objective:   the aim of the study was to evaluate the clinical effects of a mouthwash containing sage (salvia officinalis) extracts on streptococcus mutans (sm) causing dental plaque in school-aged children. material and methods: a double blind clinical trial study was conducted in a dormitory on 70 girls aged 11-14 years having the same socioeconomic and oral hygiene conditions. these students were randomly divided into 2 groups; the first group (n=35) using sage mouthwash, and the second group (n=35) using placebo mouthwash without active any ingredients. at the baseline, plaque samples obtained from the buccal surfaces of teeth were sent to laboratory to achieve sm colony count. these tests were reevaluated after 21 days of using the mouthwashes. statistical data analysis was performed using t-student tests with p<0.05 as the level of significance. results: sage mouthwash significantly reduced the colony count (p=0.001). average number of colonies in test group was 3900 per plaque sample at the baseline, and 300 after mouthwash application. in the control group, pre-test colony count was 4400 that was reduced to 4000; although this reduction wasn’t significant. conclusion: the sage mouthwash effectively reduced the number of streptococcus mutans in dental plaque.