正畸导致牙根吸收的发生率高达100%，且仍无有效的预防及治疗方法。因此，探索有效的临床干预方法从而预防治疗牙根吸收是确保高效安全正畸治疗的关键。本课题组前期的动物研究提示低强度脉冲超声（LIPUS）通过影响OPG/RANKL的比值，调节破骨细胞的分化进而对大鼠正畸性牙根吸收有抑制作用，且初步证实LIPUS对正畸性牙根吸收有修复作用。本研究拟根据前期实验基础，对超声抑制牙根吸收，促进牙骨质修复的机制展开以下研究：1.超声对成牙骨质细胞OCCM-30的生物学特性，成骨蛋白因子，成骨通路关键蛋白表达的影响；2.超声对RAW264.7细胞的生物特性及其对于破骨细胞分化的影响；3.构建OCCM-30和RAW264.7共培养模型，模拟体内微环境，研究超声对于共培养体系中两种细胞成、破骨分化的作用及其分子机制。本研究对于阐明超声抑制牙根吸收、促进牙骨质修复作用有重要的理论意义和潜在价值。

Root resorption is a side effect of orthodontic tooth movement, and the occurrence rate of which is very high. However, no effective clinical methods are available currently to prevent orthodontically induced root resorption. Therefore, to ensure the efficiency and security of the orthodontic therapy, it is critical to explore the effective clinical intervention methods to prevent root resorption. Our group find that low intensity pulsed ultrasound(LIPUS) can inhibit root resorption in rats by changing the ration of RANKL and OPG, and regulating osteoclasts differentiation. At the same time, we discovered that LIPUS have the effect of repairing root resorption. According to our previous researches, we hope to do some researches to study the mechanism of LIPUS preventing and repairing orthodontic root resorption: first, researching the effect of LIPUS on the biological characteristics and osteogenesis related proteins of cementoblasts; second, studying the effect of LIPUS on biological characteristics of cementoclasts; third, we will establish the cells co-culture system of OCCM-30 and RAW 264.7 under the LIPUS to stimulate interaction of cementoblasts and cementoclasts in vivo, to study the effect and the molecular regulation mechanism of LIPUS on the co-culture system. Our research has important theoretical significance and potential value on illuminating that LIPUS can inhibit the orthodontic root resorption and promote cementum repairing.

正畸导致牙根吸收的发生率高达100%，且仍无有效的预防及治疗方法。因此，探索有效的临床干预方法从而预防治疗牙根吸收是确保高效安全正畸治疗的关键。我们通过研究超声对成牙骨质细胞OCCM-30的生物学特性，成骨蛋白因子，成骨通路关键蛋白表达的影响，以及超声对大鼠正畸性牙根吸收的作用及其对 OPG/RANKL 比值和TNF-α 表达的影响，探索超声抑制牙根吸收，促进牙骨质修复的机制。经过一系列的实验和数据测量，我们得出结论：在体外实验中，超声能够促进成牙骨质细胞的增殖以及增强成骨相关蛋白的表达，同时在动物实验中，超声能够下调 TNF-α 的表达，上调 OPG/RANKL 的比值，减少了破牙骨质细胞的生成，有利于牙骨质向再生的方向发展。本研究对于阐明超声抑制牙根吸收、促进牙骨质修复作用有重要的理论意义和潜在价值。