State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Int J Oral Sci. 2021 Jun 28;13(1):20. doi: 10.1038/s41368-021-00125-5.
Nowadays, orthodontic treatment has become increasingly popular. However, the biological mechanisms of orthodontic tooth movement (OTM) have not been fully elucidated. We were aiming to summarize the evidences regarding the mechanisms of OTM. Firstly, we introduced the research models as a basis for further discussion of mechanisms. Secondly, we proposed a new hypothesis regarding the primary roles of periodontal ligament cells (PDLCs) and osteocytes involved in OTM mechanisms and summarized the biomechanical and biological responses of the periodontium in OTM through four steps, basically in OTM temporal sequences, as follows: (1) Extracellular mechanobiology of periodontium: biological, mechanical, and material changes of acellular components in periodontium under orthodontic forces were introduced. (2) Cell strain: the sensing, transduction, and regulation of mechanical stimuli in PDLCs and osteocytes. (3) Cell activation and differentiation: the activation and differentiation mechanisms of osteoblast and osteoclast, the force-induced sterile inflammation, and the communication networks consisting of sensors and effectors. (4) Tissue remodeling: the remodeling of bone and periodontal ligament (PDL) in the compression side and tension side responding to mechanical stimuli and root resorption. Lastly, we talked about the clinical implications of the updated OTM mechanisms, regarding optimal orthodontic force (OOF), acceleration of OTM, and prevention of root resorption.
如今，正畸治疗越来越受欢迎。然而，正畸牙齿移动（OTM）的生物学机制尚未完全阐明。我们旨在总结有关 OTM 机制的证据。首先，我们介绍了研究模型，作为进一步讨论机制的基础。其次，我们提出了一个关于牙周韧带细胞（PDLCs）和破骨细胞在 OTM 机制中主要作用的新假说，并通过四个步骤总结了牙周组织在 OTM 中的生物力学和生物学反应，基本上按照 OTM 的时间顺序，如下：（1）牙周的细胞外机械生物学：介绍了牙周组织中无细胞成分在正畸力下的生物、机械和材料变化。（2）细胞应变：PDLCs 和破骨细胞中机械刺激的感应、转导和调节。（3）细胞激活和分化：成骨细胞和破骨细胞的激活和分化机制、力诱导的无菌炎症以及由传感器和效应器组成的通讯网络。（4）组织重塑：机械刺激下骨和牙周膜（PDL）在受压侧和张紧侧的重塑以及根吸收。最后，我们讨论了更新的 OTM 机制的临床意义，包括最佳正畸力（OOF）、加速 OTM 和预防根吸收。
