Assessment of the Photobiomodulation Effect of a Blue Diode Laser on the Proliferation and Migration of Cultured Human Gingival Fibroblast Cells: A Preliminary In Vitro Study

Abstract Introduction: Photobiomodulation therapy (PBM) is emerging as an effective strategy for the management of wound healing. The application of red and near infra-red light sources in laser therapy has been the subject of most researches in recent literature. Considering the lack of sufficient evidence in assessing the blue light in PBM, we aimed to investigate the photobiomodulation effect of a blue diode laser on the proliferation and migration of cultured human gingival fibroblast cells as a preliminary in vitro study.Methods: Human gingival fibroblast cells were irradiated with a blue diode laser at a ۴۴۵ nm wavelength. Irradiation was done using three different powers of ۲۰۰ mW (irradiation times of ۵, ۱۰,۱۵, and ۲۰ seconds); ۳۰۰ mW (irradiation times of ۵, ۱۰, and ۱۵ seconds); and ۴۰۰ mW (irradiation times of ۵ and ۱۰ seconds). The fibroblast cells without laser exposure were considered as control. After ۲۴ hours of incubation, the MTT assay and the wound scratch test were performed on the cells to investigate the biomodulation effect of the blue laser on the proliferation and migration of the cells respectively. The results were analyzed by one-way ANOVA and a post-hoc Tukey test with a P value <۰.۰۵ as a statistical significance level.Results: PBM with blue diode laser at power densities of ۴۰۰ mW/cm۲ with irradiation times of ۱۰ and ۱۵ seconds corresponding to energy densities of ۴ and ۶ J/cm۲ exerted the statistically significant positive effect on both proliferation and migration of gingival fibroblast cells.Conclusion: Considering the encouraging findings of this study, PBM with blue diode laser can promote proliferation and migration of human gingival fibroblasts, the key cells involved in the process of oral wound healing. Keywords: Fibroblasts; Low-level light therapy; Cell proliferation; Cell migration assays