Irradiation at 780 nm increases proliferation rate of osteoblasts independently of dexamethasone presence

Background and Objectives: We have previously shown that phototherapy increases cell growth and impairs protein secretion of fibroblasts. Our objective was to study the effect of phototherapy on osteoblast-like cells in culture treated with dexamethasone. Study Design/Materials and Methods: Rat calvaria osteoblast-like cells were previously treated or not with dexamethasone and then, they were irradiated or not with a GaAlAs diode laser (wavelength of 780 nm, 10 mW, 3 J/cm(2)). Adhesion, proliferation, and osteonectin synthesis were analyzed. Results: Phototherapy increased the proliferation rate of cells independently of dexamethasone presence. Adhesion and osteonectin synthesis were not significantly influenced by laser and/or dexamethasone. Conclusions: Based on the conditions of this study we concluded that phototherapy acts as a proliferative stimulus on osteoblast-like cells, even under the influence of dexamethasone. Thus, we suggest that phototherapy can be of importance as co-adjuvant in bone clinical manipulation in order to accelerate bone regeneration.