Effects of low-energy laser irradiation on bone remodeling during experimental tooth movement in rats

Abstract

Background and Objective: Low-energy laser irradiation has many anabolic effects such as the acceleration of bone formation. However, its effects on tooth movement, performed by bone resorption and formation, have not been well characterized. Study Design/Materials and Methods: A total of 10 g of orthodontic force was applied to rat molars to cause experimental tooth movement. A Ga-Al-As diode laser was used to irradiate the area around the moved tooth, and after 12 days, the amount of tooth movement was measured. Calcein was injected subcutaneously to label the newly formed alveolar bone for quantitative analysis. Immunohistochemical staining of proliferating cell nuclear antigen was performed to evaluate cellular proliferation. TRAPase staining was also performed to facilitate the identification of osteoclasts. Results: In the laser irradiation group, the amount of tooth movement was significantly greater (1.3-fold) than that of the nonirradiation group in the end of the experiment. The amount of bone formation and rate of cellular proliferation in the tension side and the number of osteoclasts in the pressure side were all significantly increased in the irradiation group when compared with the nonirradiation group (P < 0.01). Conclusion:These findings suggest that low-energy laser irradiation can accelerate tooth movement accompanied with alveolar bone remodeling.

Low-Level Laser Action on Orthodontically Induced Root Resorption: Histological and Histomorphometric Evaluation

“…6 Consequently, it would be possible to accelerate the teeth movement without increasing the root resorption. The LLL can stimulate osteoclasts 28,29 during the induced tooth movement, but this effect seems contradictory for root resorption process. Osteoclasts are important to remove the hyaline area, responsible for keeping the resorption process after the interruption of the force.…”

Effect of Low Level Laser Therapy on Local Bone Resorption During Orthodontic Treatment: A Randomized Controlled Trial

“…Deoxypyridinoline (DPD) is a derivative of hydroxypyridinium, which is released during bone resorption into the blood stream and is eliminated unmodified with urine. A further collagen-derived marker of bone resorption is the C-terminal telopeptide of type I collagen, which is released in bone resorption and almost entirely excreted by the kidney (Kawasaki et al, 2000).…”

Effects of Corticision on Paradental Remodeling in Orthodontic Tooth Movement

“…Recent cellular, molecular, and tissue-level studies 1 on the biologic mechanism of tooth movement suggest that a mechanical force is not the only stimulus for inducing tooth movement. Although clinical orthodontic systems generally use mechanical forces to induce bone remodeling, the use of pharmaceutical, 2-3 electromagnetic, [4][5] laser, 6 and surgical stimuli in combination with the mechanical force for accelerating orthodontic tooth movement has attracted considerable scientific interest.…”