The Effect of Laser Therapy of 30 Mw on Bone Repair: Histological Study

Purpose: The aim of the present study was to investigate the effect of Low Level Laser Therapy (LLLT) of 30mW with a Gallium Aluminum Arsenide (GaAlAs) diode laser device (830nm) on bone repair in the tibia of the rabbit, histological study. Materials and Methods: In this study, 24 male adult rabbits were randomly selected and anesthetized, then incision was made on the skin and deep fascia of medial aspect of the tibia of each rabbit. By using drill (3mm diameter), the medial of the tibia was drilled. The animals were randomly classified to three groups: control, sham and treatment. Irradiation was started 24 h after surgery and was applied daily in 5 sites of bone with energy density 126 J/Cm2. For evaluation of repair, the animals of each group were sacrificed on the 7th and 14th days after the irradiation. The samples were collected from repaired tissue in order to histological evaluation and compartment between groups. Results: The results show that in the 7-dayssubgroup regarding the osteogenesis no difference was observed among the control, sham and treatment groups, but osteogenesis areas in the 7-days treatment subgroup, in all area of the defect site, were observed to be more active than the control and sham groups. In 14-day treatment group defect sites were completed by spongy bone while in other groups no change was observed. Conclusion: It was concluded that in the process of bone fracture repair, photochemical interaction of laser had a effect on osteogenesis trend and in the 14th day treatment subgroup, this process is more effective than others.