INVESTIGATION OF ANTIMICROBIAL EFFECT OF PHOTODYNAMIC THERAPY WITH FOTOSAN IN LABORATORY CONDITIONS

Abstract

Purpose: The present study aims to evaluate antimicrobial effect of photosensitizer Fotosan against microorganisms from endodontic flora. Material and methods: Staphtlococcusaureus ATCC29213 (MSSA), S.aureus ATCC43300 (MRSA), Enterococcus faecalis ATCC 29212, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922 were used as control strains and test bacteria. Several clinical isolates like E. faecalis, Klebsiella pneumoniae, Enterobacter cloaceae, Serratia marcescens, Morganela morganii were used supplementary. Suspensions with concentration 0.5 at MacFarland’s scale and Muller-Hinton agar were used according to criteria of EUCAST 2019. The used Fotosan was with the lowest viscosity. Plates with diameter of 100 millimeters were used in the study. The three filter paper disks were put on inoculated with testing microbial strain agar surface. The disks were consecutively soaked with 0.5 ml of Fotosan. LED lamp with λ = 630 nm was a source of light. Output power was 200 mW. The power density was 700 mW/cm2. The three disks have been consecutively illuminated, the first for 20 seconds, the second for 40 seconds and the third for 60 seconds. The plates were cultivated for 24 hours at aerobic conditions at 36oC after that. Results: The zones of inhibition of bacterial growth have varied from 8 to 10 mm for Gram-positive bacteria and 6 to 8 mm for Gram-negative bacteria. Conclusion: The presence research has confirmed that photodynamic therapy with Fotosan is an effective method for liquidation of microorganisms, especially with more expression antimicrobial effect against Gram-positive bacteria, which participate more often in endodontic microbial pathology.

Keywords

• endodontic microbiology
• photodynamic therapy