Method: There were realized 28 assays. The toluidine blue was the PS and the light was from a LED (637 ± 15nm, 40mW, 1W/cm2). These assays were divided into the following experimental groups: submitted to light-emitting diode in the presence of the toluidine blue (n=7); submitted to light-emitting diode only (n=7); treated only with the toluidine blue (n=7); no exposure to light-emitting diode nor toluidine blue (n=7). Next, serial dilutions were prepared and seeded onto Sabouraud dextrose agar for the determination of the number of colony-forming units per milliliter (CFU/ml). The results were submitted to analysis of variance and the Tukey test (p<0.05).
Result: aPDT with toluidine blue promoted a statistically significant reduction in the CFU number of C. albicans. The number of CFU was higher in the group submitted to LED only than in the group submitted to LED in the presence of the toluidine blue and it was higher for the group submitted to the toluidine blue than it was for the group submitted both to LED and toluidine blue. There was no significant statistical difference between the groups without PS.
Conclusion: We show that LED with toluidine blue used for lower power and lower time had a fungicidal effect on C. albicans facilitating the clinical use of this therapy.