牙撕脱性损伤是临床常见且治疗难度较大的一类牙外伤。牙周膜的广泛损伤是脱位牙再植后难以获得理想牙周膜性愈合的关键。本课题组前期成功建立牙脱位再植动物模型，并证明PRF可通过提高PDLSCs等干细胞的活性而获得促牙周再生与修复效果。但动物实验和临床实践都发现对再植牙施以弹性固定以保持其生理动度和咬合力刺激对牙周膜再生仍必不可少,但至今机理不明。我们前期研究证实力敏感分子MGF在牙周组织表达，发现PDLSCs中的MGF基因水平会随PRF的作用而升高，提示MGF可能在牙周损伤修复中扮演重要分子的角色。本课题拟在前期工作基础上以MGF关键分子的功能研究为突破口，利用RNAi、合成肽、基因转染、特异性信号转导通路芯片等技术系统从体内外两方面揭示MGF在力学微环境促PDLSCs /PRF双膜结构再生修复牙周组织过程中所发挥的作用及其信号转导机制。以期为撕脱再植牙获得理想的牙周膜性愈合提供新的策略和思路。

Tooth avulsion is a common dental trauma, while its treatment is relatively difficult and hard to forecast. The extensive damage and even necrosis of avulsed periodontal membrane is the key obstacle that prevent the avulsed tooth from obtaining ideal periodontal healing. Clinical experience has shown that the elastic fixation to keep the physiological mobility and occlusal force stimulation of the replanted tooth is essential for periodontal ligament regeneration, but the underlying mechanism keeps unknown. On the basis of the periodontal ligament stem cells (PDLSCs) / platelet rich fibrin (PRF) double-membrane complex construction and application for avulsed tooth replantation in dogs for periodontal healing and regeneration, the project intends to explore the regulation of in vitro and in vivo biomechanical microenvironment for PDLSCs, and further to improve periodontal healing and regeneration by optimizing the growth factors niche and mechanical microenvironment of the PDLSCs, which could provide new promises for the periodontal healing promotion of the replanted tooth after avulsion. With an eye to the mechanical sensitivity of mechano growth factor (MGF) and its existence in periodontal tissues, the project will further probe into the role and underlying signal transduction mechanism of MGF in periodontal healing promotion of injured periodontal tissue after avulsion under in vitro and in vivo biomechanical microenvironment. The whole project is expected to provide a new strategy and method for obtaining ideal periodontal healing of avulsed tooth after replantation, and provide a reference for the studies on some other tissues and organs like periodontal tissue that endures mechanical microenvironment in vivo, as well as for the possible biomechanical regulation for their regeneration and healing after trauma or damage.