Effect of Photobiomodulation Therapy with Three Wavelengths of Diode Laser on Proliferation and Survival of Stem Cells Derived from Impacted Third Molar Follicles

<b>Introduction:</b> Increased tissue regeneration is facilitated by mesenchymal stem cells (MSCs), with photobiomodulation (PBM) effectively promoting their proliferation. This study examines the impact of PBM on human third molar follicle stem cells using three diode lasers, addressing the need for further investigation regarding its parameters. <b>Methods:</b> The third molar follicle stem cells of four consented patients were removed after surgical extraction of third molars. These cells were then exposed to laser radiation with wavelengths of 660 (energy density: 3 and 5.1 J/cm²), 808 (energy density: 3 and 5 J/cm ²), and 980 (energy density: 3.2 and 5/2 J/cm²) nanometers at time intervals of 24, 48, and 72 hours. The proliferation and viability of the cells were determined using the MTT test. The data were analyzed through one-way ANOVA followed by Tukey's HSD post hoc test, utilizing SPSS software version 22, with a significance threshold of 0.05. <b>Results:</b> The highest average number of human third molar follicle stem cells was obtained at 660 nanometers and an energy density of 5.1 J/cm² in 24 hours. This specific laser protocol significantly outperformed other conditions in promoting cellular proliferation. <b>Conclusion:</b> PBM at the 660-nm wavelength administered with a dose of 5.1 J/cm² and a 24-hour incubation period appears to be the most effective condition for enhancing the proliferation and survival of human third molar follicle stem cells. These findings provide a potential basis for standardized PBM protocols in regenerative dentistry.