Evaluation of Antimicrobial Activities of Melaleuca alternifolia (Tea tree) Oil Mouthwash on Candida albicans and Streptococcus mutans: In Vitro Pilot Study

Statement of the problem: Herbal mouthwashes have attracted attention recently due to their antimicrobial and anti-inflammatory effects and fewer side effects than chemical preparations. To choose the most suitable mouthwash component among these herbal preparations, in vivo and, in vitro research should be done, respectively. Objective: The effects of the mouthwashes containing Melaleuca alternifolia (tea tree oil, TTO) on the infectious agents Streptococcus mutans and Candida albicans were evaluated. The results were compared with the effect of chlorhexidine (CHX), the accepted gold standard. Material-Method: A 2% concentration of TTO was prepared, and suspensions of microorganisms Candida albicans and Streptococcus mutans by Mc Farland 0.5 standard were obtained. The macrodilution tube method was used to determine the lowest concentration inhibiting growth, and the disk diffusion method was used to determine the growth inhibition zones. Each method was applied for both TTO and CHX. Results: It was determined that TTO did not inhibit the growth of S. mutans and C.albicans at 2% concentration and MIC value could not be obtained. On the other hand, it was observed that after the treatment with CHX, in C.albicans and,S.mutans samples inhibition zones with the diameters of 10 and 20 mm were formed, respectively. Conclusion: TTO cannot be a successful alternative to CHX for its 2% concentration; It has been concluded that it can increase its antimicrobial effect with different concentrations and other essential oil combinations.