Effect of Different Disinfecting Agents on Dental Impressions Contaminated with Candida albicans

Introduction: This research was carried out to compare the effects of 0.525% and 5.25% NaOCl, 2% H2O2, and 16-mg/mL propolis on additional silicone impression materials contaminated with Candida albicans at 5- and 10-minute exposure times, to evaluate the hypotheses of this study that propolis can be used for disinfecting of dental impressions. Materials and methods: A total of 122 silicone impressions were prepared. Two samples were considered the negative controls, and the rest were contaminated with C. albicans fungal species and disinfected with 0.525% NaOCl, 5.25% NaOCl, 2% H2O2, 16-mg/mL propolis, and 96% ethyl alcohol for 5 and 10 minutes (10 samples for each interval in each group). The data were analyzed with Kruskal–Wallis and Mann–Whitney U tests in all the groups at 5- and 10-minute intervals. Results: All the disinfecting agents significantly decreased C. albicans colony counts at both intervals compared to the control groups (P = 0.00). The differences in the disinfecting effects were significant between the four study groups (P = 0.00). The most significant effects were related to NaOCl at both intervals and concentrations and 2% H2O2 at the 10-minute interval (P = 0.001), followed by 2% H2O2 at the 5-minute interval and propolis (P = 0.001). Concerning propolis (P = 0.001) and 2% H2O2 (P = 0.004), the effect of exposure time was significant. Conclusion: All the disinfecting agents in the present study can be used to disinfect impressions contaminated with C. albicans; however, concerning propolis, although it resulted in significant decreases in C. albicans colony counts, the elimination of the remaining colonies was ineffective.