Blue photosensitizers for aPDT eliminate Aggregatibacter actinomycetemcomitans in the absence of light: An in vitro study

Publication date: Available online 14 March 2019Source: Journal of Photochemistry and Photobiology B: BiologyAuthor(s): Luisa Andrade Valle, Marcelo Milanda Ribeiro Lopes, Mariana Schutzer Ragghianti Zangrando, Adriana Campos Passanezi Sant'Ana, Sebastião Luiz Aguiar Greghi, Maria Lúcia Rubo de Rezende, Carla Andreotti DamanteAbstractThe main treatment of periodontal disease is the mechanical removal of supra and subgingival biofilm. Adjuvant therapies as antimicrobial photodynamic therapy (aPDT) may offer improved clinical and microbiological results. The aim of this in vitro study was to evaluate the effect of toluidine and methylene blue dyes, associated with red laser and LED, on elimination of a suspension of Aggregatibacter actinomycetemcomitans (A.a). Experimental groups (n = 29) consisted of positive (broth) and negative (gentamicin) controls, three different dyes concentrations (0.05; 0.1; 10 mg/ml) alone or associated with laser (660 nm) at two power settings (70 and 100 mW) and LED (627 ± 10 nm). Bacterial suspension received all treatments, and after serial dilutions they were cultured for 24 h in petri dishes for colony forming unit counts. Data were analyzed by ANOVA complemented by Tukey's test (p < 0.05). The results showed that both dyes, at a concentration of 10 mg/ml, alone or associated with laser and LED, caused 100% of death similar to the negative control (p > 0.05). It can be concluded that blue dyes for aPDT, at high...
Source: Journal of Photochemistry and Photobiology B: Biology - Category: Speech-Language Pathology Source Type: research