Elucidation of the effects of periodontal pathogenic factor and excessive mechanical stress on signaling pathway of orthodontic tooth movement

我们发现IL-1 β的组成性表达对于机械应力诱导成骨细胞MIP-2和MCP-1的表达至关重要，这种表达依赖于MyD88 （IL-1受体和TLRs的适配分子）。因此，提示MyD88信号通路参与正畸治疗早期骨重塑。我们的研究结果还表明，高浓度的il -1 β可能促进机械应力诱导的成骨细胞的炎症反应。在临床研究中，发现牙根长度与咬合接触丧失有关。此外，部分不良的骨桥在植骨后早期通过正畸牙齿运动得到改善。这些结果表明，由咬合力和机械应力引起的功能应力可能促进根长形成和骨重塑。

We found that the constitutive expression of IL-1beta is essential for the induced expression for MIP-2 and MCP-1 in osteoblasts by mechanical stresses in a manner dependent on MyD88, an adaptor molecule for IL-1 receptor and TLRs. Thus, it is suggested that MyD88 signaling pathway is involved in bone remodeling in the early phase of orthodontic treatment. Our findings also indicated that high level concentrations of IL-1beta may promote inflammatory responses of osteoblasts induced by mechanical stress. In the clinical research, it was found that the dental root length was related to the loss of occlusal contact. Additionally, some of the poor bone bridges were improved by orthodontic tooth movement in the early phase after bone graft. These results suggested that the functional stress by occlusal force and mechanical stress may promote root-length formation and bone remodeling.