Low-level laser therapy, at 60 J/cm~2 associated with a Biosilicate~® increase in bone deposition and indentation biomechanical properties of callus in osteopenic rats

摘要

We investigate the effects of a novel bioactive material (Biosilicate~®) and low-level laser therapy (LLLT), at 60 J/cm~2, on bone-fracture consolidation in osteoporotic rats. Forty female Wistar rats are submitted to the ovariectomy, to induce osteopenia. Eight weeks after the ovariectomy, the animals are randomly divided into four groups, with 10 animals each: bone defect control group; bone defect filled with Biosilicate group; bone defect irradiated with laser at 60 J/cm~2 group; bone defect filled with Biosilicate and irradiated with LLLT, at 60 J/cm~2 group. Laser irradiation is initiated immediately after surgery and performed every 48 h for 14 days. Histopathological analysis points out that bone defects are predominantly filled with the biomaterial in specimens treated with Biosilicate. In the 60-J/cm~2 laser plus Biosilicate group, the biomaterial fills all bone defects, which also contained woven bone and granulation tissue. Also, the biomechanical properties are increased in the animals treated with Biosilicate associated to lasertherapy. Our results indicate that laser therapy improves bone repair process in contact with Biosilicate as a result of increasing bone formation as well as indentation biomechanical properties.