Clinical use of photodynamic antimicrobial chemotherapy for the treatment of deep carious lesions

摘要

The purpose of this study was to assess photodynamic antimicrobial chemotherapy (PACT) via irradiation,nusing a low power laser associated with a photosensitization dye, as an alternative to remove cariogenicnmicroorganisms by drilling. Remaining dentinal samples in deep carious lesions on permanent molars (n = 26)nwere treated with 0.01% methylene blue dye and irradiated with a low power laser (InGaAIP – indium galliumnaluminum phosphide; λ = 660 nm; 100 mW; 320 Jcm−2; 90 s; 9J). Samples of dentin from the pulpal wallnregion were collected with a micropunch before and immediately after PACT and kept in a transport medium fornmicrobiological analysis. Samples were cultured in plates of Brucella blood agar, Mitis Salivarius Bacitracin agarnand Rogosa SL agar to determine the total viable bacteria, mutans streptococci and Lactobacillus spp. counts,nrespectively. After incubation, colony-forming units were counted andmicrobial reduction was calculated for eachngroup of bacteria. PACT led to statistically significant reductions in mutans streptococci (1.38 log), Lactobacillusnspp. (0.93 log), and total viable bacteria (0.91 log). This therapy may be an appropriate approach for the treatmentnof deep carious lesions using minimally invasive procedures.