Investigation of the effect of Essential-Oils mouthrinse on induced bacteremia

Introduction: The objective of this randomized, single-center, placebo-controlled, 2-week cross-over study was to evaluate the subgingival germ-killing efficacy of an essential oil-containing mouthrinse, as determined by levels of bloodstream bacteria induced by eating an apple. Method: Bacteremia was induced by mastication using an apple insult. Blood samples were obtained before and after the insult. After screening, 22 participants with mild to moderate gingivitis and an increment of 10 CFU/mL or more in the blood after the insult were qualified to participate, and 19 subjects completed. During normalization, subjects brushed using a fluoride dentifrice and soft bristled toothbrush for 7 days. Baseline blood samples were drawn to establish bacteria levels within 2min ±30s after chewing an apple. Subjects were then randomized into 2 groups: Essential oil (EO) group and control group (C). Rinsing was supervised during weekdays. On day 15, pre-insult blood draw, apple insult and post-insult blood draw were performed as described above. After 2-week wash-out, subjects were crossed over to the other treatment. Changes in total level of bacteria in the bloodstream were calculated and the difference between Day 15 and baseline was analyzed using analysis of covariance (ANCOVA). Results: After use of EO mouthrinse as directed for a two-week period, levels of total aerobic bacteria in the blood decreased from 25.7CFU/mL at baseline to 8.0CFU/mL (p<0.001), a 67.3% reduction. Levels of total anaerobic bacteria decreased from 20.5CFU/mL at baseline to 6.0CFU/mL (p<0.001), a 70.3% reduction. The control rinse treatment did not reduce bacteremia levels when comparing baseline and day 15 sampling levels. Conclusion: This well-controlled, randomized, 2-week cross-over study showed that the plaque and gingivitis germ killing action of an essential oil containing mouthrinse significantly reduced the amount of bacteria that enter the bloodstream from the mouth, i.e., bacteremia.