Bactericidal Effect of Helium-Neon Laser on Photosensitized Staphylococcus aureus in Vitro

Abstract

Background: Many studies had shown that low power He­ Ne laser therapy was effective as bactericidal modality, while others did not found so based on this conflicting research, the use of He-Ne laser as bactericidal modality with direct effect is still controversial. The Purpose of this research was to study the bactericidal effect of low power He-Ne laser on photosensitized Staphylococcus aureus bacteria in vitro. Methods Staphylococcus aureus bacteria were used in this study, One hundred samples were used (86 standard strains (ATCC25923) ru1d 14 isolated strains in Microbiology ru1d Immunology Department), 15 mW He-Ne gas laser was used in this study with wavelength 632.8 nm. Toludine Blue 0 (TBO) (CI52040) was utilized as photosensiting agent in this study. Results: of these study showed negative effect ofHe-Ne laser on 98 plates of Staphylococcus aureus bacteria out of one hundred plates. Discussion: This results has been attributed to susceptibility of Staphylococcus aureus bacteria strain that has been utilized in this current study, in addition the results would have been expected to be more efficient if Gallium Aluminum Phosphate laser has been utilized instead of He-Ne laser in the current study because of its reported bactericidal effect, which is more powerful than He-Ne laser, however He-Ne laser has been utilized because of its availability in faculty of physical therapy while Ga-Al-P laser device has not been available for these research work. Conclusion: within limitation of these study 15mW He-Ne laser has no bactericidal effect on photosensitized Staphylococcus aureus bacteria.