Oral candidosis is the most common mycotic infection of the oral cavity, and is caused by Candida species, the commonest being Candida albicans. These micro-organisms are commonly found in the oral cavity in relation to commensalism, but this type of fungus has the ability to change their morphology, causing infection of the oral tissues. The oral infection is usually treated with topical and systemic antifungal drugs. However, the use of antimicrobial drugs can lead to the development of resistance of microrganisms. In this context, photodynamic therapy has been studied as an alternative method for treating infectious diseases. This study evaluated the effect of photodynamic therapy (PDT) mediated by Photodithazine® (PDZ) and LED light on the virulence factors of Candida albicans. Standardized suspensions of each strain will be performed, and after 48 hours of biofilms formation, they will be treated with 100 mg / L of PDZ for 20 minutes (pre-irradiation time), and exposed to LED light at 37.5 J/cm2 (660 nm) for 9 minutes. Cells suspensions will be treated only with additional PDZ or light, and control will consist of samples that will not receive PDZ nor light. Serial dilutions of the samples will be plated on Sabouraud Dextrose Agar. After 48 hours at 37 ° C, the viable colonies will be quantified. ). For evaluation of virulence factors two colonies per plate will be isolated and resssuspended in PBS. Standardization of cell concentration will be performed spectrophotometrically according to the parameters required in each of the methods used. The virulence factors evaluated in samples exposed or not PDT will be: capacity for adhesion and biofilm formation on abiotic surfaces, the ability to synthesize specific degradative enzymes (protease and phospholipase) and formation of germ tubes and pseudo-hyphae. The control group consisted of suspensions that will be not receive either PDZ or light. The data will be analyzed according to appropriate statistical method.
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