Yoshida T, Yamaguchi M, Utsunomiya T, Kato M, Arai Y, Kaneda T, Yamamoto H, Kasai K
Department of Orthodontics, Nihon University School of Dentistry at Matsudo, Chiba, Japan.
Orthod Craniofac Res. 2009 Nov;12(4):289-98. doi: 10.1111/j.1601-6343.2009.01464.x.
Previously, the authors have reported the acceleration of tooth movement and osteoclastogenesis on the pressure site in an experimental tooth movement model by low-energy laser irradiation (LELI), which stimulated the RANK/RANKL system and c-fms/macrophage colony-stimulating factor system. However, the effect of LELI on osteogenesis on the tension site is not known clearly. Moreover, the temporal changes in alveolar bone during tooth movement have not been investigated as yet. Therefore, the present study was designed to examine the effects of LELI on alveolar bone remodeling during experimental tooth movement, and observe the temporal bone mineral density (BMD) using micro-computed tomography (muCT).
To induce experimental tooth movement in rats, 10 g force was applied to the upper right first molar with Nickel titanium closed-coil. Next, a gallium-aluminum-arsenide (Ga-Al-As) diode laser was used to irradiate the area around the moved tooth, and BMD and the amount of tooth movement were measured by muCT scanning for 21 days. Histopathological examination was also performed.
The amount of tooth movement in the LELI group was significantly greater than in the non-irradiation group by the end of the experimental period. Further, compared with the non-irradiation group, the fall of BMD was less in the LELI group.
These findings suggest that LELI accelerates the velocity of tooth movement via stimulation of the alveolar bone remodeling.
此前，作者在实验性牙齿移动模型中报道了低能量激光照射（LELI）可加速压力部位的牙齿移动和成骨细胞生成，其刺激了RANK/RANKL系统和c-fms/巨噬细胞集落刺激因子系统。然而，LELI对张力部位骨生成的影响尚不清楚。此外，牙齿移动过程中牙槽骨的时间变化尚未得到研究。因此，本研究旨在探讨LELI对实验性牙齿移动过程中牙槽骨重塑的影响，并使用微计算机断层扫描（muCT）观察骨密度（BMD）的时间变化。
为诱导大鼠实验性牙齿移动，用镍钛闭合线圈对右上第一磨牙施加10g力。接下来，使用砷化镓铝（Ga-Al-As）二极管激光照射移动牙齿周围区域，并通过muCT扫描测量21天的骨密度和牙齿移动量。还进行了组织病理学检查。
到实验期结束时，LELI组的牙齿移动量显著大于非照射组。此外，与非照射组相比，LELI组的骨密度下降较少。
这些发现表明，LELI通过刺激牙槽骨重塑来加速牙齿移动速度。
