Effects of Near-Infrared Laser Biostimulation on Bone Cells Number and Activity during Orthodontic Therapy: An Animal Study

Purpose: Laser photobiostimulation has recently gained recognition as a non-invasive and effective technique for accelerating orthodontic tooth movement and enhancing bone healing. This article evaluates the effects of laser biostimulation at an energy density of 15.9 Joules/cm² on the amount of orthodontic movement and its impact at the histological level. Materials and Methods: Thirty adult male albino rabbits were randomly chosen to form two groups (n=15 per group): a Control (C) and a Laser Treatment (LT) group. The LT group received laser treatment for three weeks at 976 ± 10 nm and an energy density of 15.9 Joules/cm². Laser irradiation was applied to four specific spots on the lower incisors for 80 seconds, administered on days 0, 3, 6, 9, 11, 13, 16, 18, and 20. Five rabbits from each group were euthanized at 7, 14, and 21 days for subsequent analysis. Results: The amount of orthodontic movement, the extent of osteogenesis, osteoblasts, and osteoclast counts were significantly larger in the laser-exposed group than in the unexposed group. Notably, bone alkaline phosphatase and tartrate-resistant acid phosphatase 5b activity significantly increased, particularly at two weeks relative to the control group. Conclusion: Laser biostimulation offered evidence of improved parameters of teeth movement, providing insight to enhance the orthodontic therapy outcome.