The Evaluation of 660, 810, and 940nm Laser Wavelengths on Nystatin-Resistant Candida albicans: An In-Vitro Study

Background:Candida albicans is the primary pathogen responsible for oral candidiasis. The emerging resistance of fungi to antifungal agents has led to the development of new fungicidal treatments. Objectives: This study aimed to analyze the effects of 660, 810, and 940 nm laser wavelengths on nystatin-resistant C. albicans. Methods: In this in vitro study, a standard strain of C. albicans and eight nystatin-resistant isolates were irradiated with 660, 810, and 940 nm diode lasers for 40 and 80 seconds (s) and compared with nystatin. Colony numbers and nystatin susceptibility were evaluated using the minimum inhibitory concentration (MIC). Results: All laser wavelengths significantly decreased the colony count of the standard strain of C. albicans, with 40s of 810 nm laser irradiation causing the maximum reduction in colony count (P810 nm 0.001). Similarly, all laser wavelengths significantly reduced the colony count of nystatin-resistant isolates, and they were more effective than nystatin (unlike with the standard strain) (P 0.05). The 810 nm laser irradiation for 40s demonstrated the greatest effect on MIC among the laser groups. Conclusions: The 810 nm laser for 40s was the most effective in reducing the colony count of nystatin-resistant C. albicans, and it eliminated resistance in all clinical isolates.