Effect of Low-Level Laser of 650nm on Viability of Porphyromonas Gingivalis with and with Out Photosensitizers: An Invitro Study

Porphyromonas gingivalis is a major pathogen associated with initiation and progression of periodontitis. Aim and Objective The aim of the study is to compare effect of lowlevel laser of wavelength 650nm on viability of porphyromonas gingivalis with and without photosensitisers. Methods Thirty samples of bacterial suspensions (200µl) were prepared and divided into six groups .Group 1- laser group (low level laser with wavelength of 650nm, and irradiation time of 30 s), Group 2- Methylene blue + laser group (after pre-irradiation time of 10 min, laser was irradiated), and Group 3- Toluidine blue O + laser group (after pre irradiation time of 10 min, LED was irradiated), Group 4 -Methylene blue Group 5 - Toluidine blue O (TBO) and Group 6- Control group (no treatment), Then, 20 μL of each sample was cultured in blood agar plates and incubated for 72 hours in microaerophilic atmosphere for colony counting. Result The concentration of P. gingivalis was significantly reduced after using the Methylene blue + laser and the Toluidine blue O + laser group. (P values < 0.005) Conclusion Within the constraints of this investigation, it can be deduced that photodynamic inactivation applying a laser and photosensitizers like Methylene blue and toluidine blue was more efficient than photosensitizers and laser irradiation alone in eliminating P. gingivalis