Effect of photodynamic therapy with two photosensitizers on Candida albicans

• Photodynamic therapy is an effective method to the decrease of Candida albicans CFUs.
• Laser 808 nm plus ICG has the best effect to decrease Candida albicans CFUs.
• Photodynamic therapy with laser 808 nm plus ICG is alternative method to the decrease of CFUs instead of nystatin.

Background and ObjectivesOral candidiasis (OC) is an opportunistic infection of the oral cavity most commonly caused by Candida albicans (C. albicans). Considering the drawbacks of standard treatments with antifungal agents, this study sought to assess the efficacy of photodynamic therapy (PDT) with methylene blue (MB) and indocyanine green (ICG) photosensitizers against C. albicans.Materials and MethodsIn this in-vitro, experimental study, 130 samples of C. albicans standard suspensions were subjected to various combinations of MB and ICG photosensitizers with and without laser irradiation with different exposure parameters, nystatin and chlorhexidine (CHX) in 13 groups of 10. Samples were cultured in microplates containing Sabouraud dextrose agar medium and colony forming units (CFUs) were counted after 24 h of incubation at 37 °C. Data were analyzed by SPSS version 19.0, one-way ANOVA and Tamhane's test.ResultsThe maximum number of CFUs was seen in the control group (mean of 214,200 CFUs with a log value of 5.32) while the minimum values were noted in the laser (808 nm and 100 Hz PRR) plus ICG (mean of 13,460 CFUs and log value of 4.12) and nystatin (mean of 13,940 CFUs and log value of 4.14) groups.ConclusionWithin the limitations of this in vitro study, the results revealed that laser application (808 nm, 100 Hz PRR) plus ICG caused a significant reduction in C. albicans CFUs.