Efeitos da terapia fotodinâmica e fotossensibilizadores (azul de toluidina e própolis vermelha) sobre micro-organismos causadores da cárie dental e de infecções endodônticas

Abstract

Introduction: Photodynamic therapy (PDT) may to reduce pathogenic microorganisms in the oral cavity and has been widely used as an adjuvant in several dental procedures. Dyes such as phenothiazines are the most used in this therapy, but also thought to use red propolis as a photosensitizer for performing PDT. Objectives: Evaluate the antimicrobial activity of low power red laser with or without toluidine blue or red propolis on planktonic cells and/or biofilm of microorganisms commonly associated with dental caries and endodontic infections. Methodology: The serial microdilution method was used to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of toluidine blue and red propolis on planktonic cells and mature biofilms, submitted or not to laser therapy, by means of quantification of viable cells, in relation to the control vehicle. Results: Gram-positive microorganisms such as Streptococcus mutans, Lactobacillus acidophylus and Enterococcus faecalis were more susceptible to PDT with different dyes. Candida albicans and Pseudomonas aeruginosa were more resistant to treatments. Biofilms were completely destroyed after 24 hours of exposure to red propolis in the CBM to 1625 for 15000 µg/mL and association with PDT (9J, 90 sec). Conclusion: PDT offers a good prognosis for anticariogenic therapy, as well as potential clinical applicability, when associated with propolis, in endodontic practice, mainly as a delay medication (or long-acting medication). More tests will be needed to validate the use of this material in vivo.