In vitro bactericidal effect of Nd:YAG laser on Actinomyces israelii.

Abstract

A bactericidal effect has been reported by the use of near-infrared laser light on both Gram-positive and Gram-negative bacteria. The aim of this study was to evaluate the effect of Nd:YAG laser on Actinomyces israelii, filamentous bacteria causing cervicofacial actinomycosis. Experiments were realized on bacterial cells in saline suspension or streaked on Mueller-Hinton (MH) agar plates with or without India ink. Laser application was performed in Eppendorf tubes with different powers and frequencies for 40 s; bacterial suspensions were then streaked on agar plates and incubated at 35 °C in proper conditions for 5 days before colony enumeration. A reduction of colony number variable from 60.13 to 100 % for powers of 2, 4, and 6 W at 25-50 Hz of frequency was observed in comparison with growth control. For agar plates, laser application was performed with different powers at 50 Hz for 60 s. A growth inhibition was observed after 5 days of incubation on MH plates with powers of 6 W and on MH-ink plates with all applied powers. This preliminary study showed a bactericidal effect caused by Nd:YAG laser application worthy to be evaluated in further experiments in vivo.

• Authors: Paolo Vescovi, Stefania Conti, Elisabetta Merigo, Tecla Ciociola, Luciano Polonelli, Maddalena Manfredi, Marco Meleti, Carlo Fornaini, Jean-Paul Rocca, S Amir Nammour
• Journal: Lasers in medical science (Lasers Med Sci) Vol. 28 Issue 4 Pg. 1131-5 (Jul 2013) ISSN: 1435-604X [Electronic] England
• PMID: 23053244 (Publication Type: Journal Article)

Topics

• Actinomyces (growth & development, pathogenicity, radiation effects)
• Actinomycosis, Cervicofacial (microbiology, radiotherapy)
• Bacterial Load
• Humans
• Lasers, Solid-State (therapeutic use)
• Low-Level Light Therapy (methods)