ANTIMICROBIAL ACTIVITY OF PHOTODYNAMIC THERAPY AGAINST MICROORGANISMS ISOLATED FROM DEEP CARIOUS LESIONS

Introduction: Photodynamic therapy (PDT) is an innovative method, supporting routine treatment methods and accelerating the healing process. It is a method for treatment of pathogens and tumor cells with photoactive dye, in the presence of oxygen. PDT is minimally invasive and high- selective method against specific cells and is equally effective against sensitive and resistant to antibiotics microorganisms. Aim: The purpose of this study was to determine the antimicrobial activity of the PDT (Fotosan-Agent High) against microorganisms isolated from deep carious lesions. Materials and methods: For the purpose of this study were selected 20 patients ( n=20) with primary, deep carious lesions on permanent teeth with complete root development All prepared cavities were class I and class II, and the treatment method was indirect pulp capping. Cavities were prepared with high and low-speed handpieces and water- air cooling. Two microbiological samples were taken of each cavity: Group 1 - Microbiological samples after cavity treatment with Aqua destillata (n=20) Group 2 - Microbiological samples after cavity treatment with PDT (Photosensitizer Fotosan (Agent high) and irradiation with a diode laser, λ = 632 nm, for 60 seconds) (n=20) The samples were placed in eppendorf tube with standard transport medium and transported to the microbiological laboratory for determination of microbial number and identification of the isolated microorganisms. The statistical analysis was made with non- parametric test of‘ McNemar. Results: In 82.35% of cases (14 of 17 cases) after treatment bacterial infection was totally eliminated. In 17.65% (3 of 17 cases) was determined reduction of bacteria count from 100 to 1000 times. The statistical analysis with non- parametric test of‘ McNemar presented significantly higher proportion of cases with bacterial elimination after photodynamic therapy ( p < 0.001). Conclusion: After photodynamic desinfection were determined considerable elimination of microbial infection and reduction of bacterial variety and bacterial number. On the ground of these results it can be concluded, that photodynamic therapy is an effective method of treatment and removal of microorganisms from deep carious lesions and support the healing processes in the dentin and dental pulp.