Background and Aims: Denture stomatitis is inflammatory reaction of oral mucosa to damaging stimuli. This lesion is recognized as the most common mucosal lesions in patients using dentures. Infectious source of this lesion is related to Candida family (especially Candida Albicans). The aim of this study was to investigate anti-fungal effect of chlorhexidine against Candida albicans and compare it with nystatin in order to treatment choice of denture stomatitis.

Materials and Methods: This was an experimental investigation, Three concentrations of Candida albicans (10⁵, 10⁶, 10⁷ CFU/mL) were prepared. Chlorhexidine and nystatin were added separately to the same amounts of Candida Albicans, of different concentrations. Each mixture was then sampled at the four specific intervals of 1,2,3 and 4 minutes. (10 times at each interval). In the control group sterile saline was added to Candida Albicans suspensions and the same procedures were done. At last, the number of formed colonies was counted for each plate (totally 360 plates) and and analyzed by means of ANOVA and Friedman Test. P<0.05 was considered significant.

Results: Chlorhexidine showed noticeable anti-candida effect on the concentrations of 10⁵ and 10⁶ CFU/mL of candida Albicans. It was as effective as nystatin in these concentrations, but nystatin was statistically more effective on the concentration of 10⁷ CFU/mL. For all concentrations, both studied material had more effectiveness in comparison with the control group for all concentrations.

Conclusion: Chlorhexidine showed noticeable anti-candida effects at low and medium concentrations of Candida Albicans.