前列腺素E2对生长发育晚期比格犬下颌前伸后骨改建影响的研究

There was strong willing to doing orthodontic treatment of Skeletal class II malocclusion with mandibular retrusion patients because of bad profile. However, it is hard to treat the late growth patients with skeletal class II malocclusions. One of the hard problem in the orthodontic area is how to improve the growth remodeling of the temporal mandibular joint and mandible of late growth patients with functional treatment. It was founded that prostaglandins E2(PGE2) can enhance anabolic effect of bone. And studies had indicated the endogenous PGE2 can stimulate remodeling of temporal mandibular joint in growing rat. Though studies had involved in injecting PGE2 in some other bone and joint areas, there were few studies discussing about injecting PGE2 in temporal mandibular joint. The aim of this project was to study the effects of exogenous PGE2 on the remodeling of temporal mandibular joint and mandible of late growth beagle. This study planned to establish mandibular protraction model of beagle and contrast the differences among the late growth beagle with injecting PGE2 , late growth beagle without injecting PGE2 and the growing beagle without injecting PGE2 by morphologic, cephalometric, CBCT, histological, immunohistochemistrical and in situ hybridization methods. Different concentration of PGE2 and injecting period were invested in this study to seek the optimal concentration and injecting period. And it planned to analyse the molecular biology mechanism of late growth beagle treating with functional appliance further. This study can provide important experiment references and theory instruction on applying PGE2 in late growth patients with functional appliance treatment.

骨性II类下颌后缩严重影响面貌美观，患者矫治愿望强烈。但生长发育晚期骨性II类下颌后缩患者的治疗是正畸治疗的难点，如何增加此类患者功能矫治中颞下颌关节和下颌骨的生长改建，成为亟待解决的问题。学者们对已过生长发育高峰期动物诸多骨关节注射前列腺素E2（PGE2）都发现其可促进骨关节改建，对颞下颌关节仅局限于生长发育期内源性PGE2的研究，关于外源性PGE2对生长发育晚期颞下颌关节及下颌骨的影响国内外鲜见报道。本项目拟建立使生长发育晚期比格犬下颌前伸的固定功能矫治的动物模型，通过形态学、影像学、组织学、免疫组织化学和原位杂交等方法，将注射PGE2组与未注射组及生长发育高峰期组进行对比，研究PGE2对生长发育晚期比格犬采用固定功能矫治器治疗后颞下颌关节和下颌骨改建的影响，并深入探求PGE2的最佳浓度和作用周期，进一步从细胞层面和分子层面探讨生长发育晚期比格犬功能矫治的分子生物学机制。

骨性Ⅱ类下颌后缩严重影响面貌美观，患者矫治愿望强烈。但生长发育晚期骨性Ⅱ类下颌后缩患者的治疗是正畸治疗的难点，如何增加此类患者功能矫治中颞下颌关节和下颌骨的生长改建，成为亟待解决的问题。前列腺素E2（PGE2）与骨组织的生长改建密切相关，并且国内外已有很多关于PGE2对成年实验动物其他骨关节影响的报道。本项目将下颌前伸功能性矫治与PGE2局部注射相结合，探讨二者对颞下颌关节改建及下颌骨的生长是否具有促进作用，以寻求对生长发育晚期骨性Ⅱ类下颌后缩患者治疗的新思路。本研究通过建立生长发育晚期比格犬和SD大鼠下颌前伸的实验模型，以模拟生长发育晚期骨性Ⅱ类患者下颌前伸的功能性矫治，并采用PGE2对其双侧颞下颌关节进行局部注射，再采用CBCT影像学分析、免疫组织化学染色和组织病理学分析等手段，研究发现下颌前伸能促进生长发育晚期比格犬和SD大鼠髁突软骨内成骨，同时结合适宜浓度PGE2注射时，这种成骨效应更明显。