Antifungal Activity of Tea Tree Oil, Chlorhexidine, and Nystatin against Candida albicans: A Comparative Study

Objective: To evaluate the antifungal effect of 25% Tea tree oil and compare it to 2% Chlorhexidine and Nystatin against Candida albicans at both the 4th day and 7th day of inoculation to explore potential alternative treatment options for fungal infections in endodontic therapy. Material and Methods: 82 single-canal human mandibular premolar teeth were cleaned, prepared, and inoculated with a C. albicans suspension. After incubating for 4 and 7 days, the teeth were randomly assigned to receive one of four treatments: Nystatin, Chlorhexidine (CHX), Tea tree oil (TTO), or Dimethyl Sulfoxide (DMSO). After treatment, samples were rinsed and dried. Dentine shavings were collected and incubated to observe the growth of C. albicans. The antifungal activity was measured by the number of Candida colony-forming units. Two-way ANOVA followed by post-hoc Tukey's test was applied to compare the CFU growth. Results: TTO exhibited comparable antifungal activity to CHX (p=0.976) and superior antifungal activity compared to Nystatin (p<0.001). Conclusion: 25% Tea tree oil shows antifungal efficacy against C. albicans, comparable to 2% Chlorhexidine, suggesting it could be a viable alternative for endodontic treatments. However, Nystatin demonstrated only limited antifungal effectiveness.