Evaluation of the efficacy of AmPDT of oral microorganisms with Photogem~? associated to red LED (λ640ηm±5ηm): In vitro

摘要

The aim of this study is to evaluate the Antimicrobial Photodynamic Therapy (AmPDT) of microorganisms mediated by red LED (λ640 ± 5 ηm, 120 mW, spot of 0.785 cm~2) associated with Photogem~?. Microorganisms of the posterior dorsal region of the tongue and oral mucosa were collected and inoculated in 8 mL of TSB medium overnight followed by inverse homogenization. Culture plates with 24 wells were used for the irradiated and non-irradiated species. Each well received 400 μL of the suspension containing the microorganisms. In eight wells no Photogem~? was used and they were the irradiated and non-irradiated controls. The remain of the wells had Photogem~? applied with a pre-irradiation time of 5 min in concentrations of 40, 20, 10, 5 e 2.5 μg/mL. LED was applied for 5 min and 45 sec (50 J/cm~2). After agitation, 200 μL were withdrawn from each well and colorimetric measurements were immediately taken. Other 200 μL were withdrawn from the wells after 1 hour in bacteriological incubator for a second measurement. The best results found were for 40 μg/mL of Photogem~? associated with LED irradiation and immediate (36.7%) and for 5 μg/mL with LED irradiation with measurements one hour after incubation (42.8%). This study suggests that antimicrobial photodynamic therapy with Photogem~? associated to red LED can be a potential mechanism of control of oral microorganisms.