Accelerates bone maturation with the synthetic 3-benzothiepin derivative in distraction osteogenesis in rats.

牵张成骨是一种增加骨长度的方法。牵引成骨技术在颅面外科的应用改变了先天性和后天性颅面缺损的治疗方法。本研究采用12周龄雄性Wister大鼠，体重约400g，购自Charls River Japan，建立下颌骨牵张成骨的动物模型，观察牵张成骨过程中的组织学和超微结构变化。手术是在全身麻醉下进行的。剃去覆盖右半下颌骨的皮肤并切开，暴露下颌骨。在计划截骨部位前后放置4枚1.2 x 12 mm钛微型螺钉。使用金刚石圆盘在第2和第3磨牙之间对下颌骨进行截骨，应用由嵌入甲基丙烯酸甲酯模具的千斤顶螺钉组成的定制牵引装置，并分层闭合皮肤和软组织。在5天的潜伏期后， 关于我们 以0.2mm的速度每天两次牵张10 d，并在5、15、36和50 d四个不同时间点处死大鼠，进行组织学检查和三维显微计算机断层重建，牵张完成后，可识别出明显的前牙反牙合，在牵张间隙内观察到少量不透射线的线。牵引后3周，注意到牵引间隙内的不透射线性增加。牵张后5周，X线片显示牵张间隙内完全骨化的骨再生。下颌骨的组织学检查显示，完成牵张后，有典型的软骨内骨形成和膜内骨形成。牵引后3周，观察到新形成的骨增加，导致牵引间隙几乎完全闭合。牵张后5周，牵张间隙完全骨化，并注意到再生骨重建为更成熟的板层骨的证据增加。总之，证明了这种牵张成骨大鼠模型的实用性。

Distraction osteogenesis is a method of increasing bone length. The application of distraction osteogenesis to craniofacial surgery has altered the approach and treatment of congenital and acquired craniofacial defects. This study investigated the histologic and ultrastructural changes associated with mandibular distraction osteogenesis in animal model.Male Wister rats, 12 weeks old and weighing about 400g, were purchased from Charls River Japan. The operation was performed under general anesthesia. The skin overlaying the right hemimandible was shaved and incised, and the mandible exposed. Four 1.2 x 12-mm titanium micro screws were placed anterior and posterior to the planned osteotomy site. The mandible was osteotomized between the 2nd and 3rd molars using a diamond disk, a custom-made distraction device consisting of a Jack-screw embedded in methyl methacrylate mold was applied, and the skin and soft tissue were closed in layers. After a 5-day latency period, the mandibles were dis … More tracted at a rate of 0.2 mm twice a day for 10 days and rats were sacrificed at four different time points (5,15,36,and 50 days) for histologic examination and three-dimensional micro-computed tomographic reconstructions.After completion of distraction, obvious anterior cross-bite was recognized with a few radiopaque lines noted within the distraction gap. Three weeks after distraction, increasing radiopacity was noted within the distraction gap. Five weeks after distraction, fully ossified bony regenerate was demonstrated radiographically within the distraction gap. Histologic examination of the mandibles demonstrated typical endochondral bone formation and intramembraneous bone formation after completion of distraction. Three weeks after distraction, incresed newly formed bone was noted and resulted in a near complete closure of the distraction gap. Five weeks after distraction, the distraction gap was completely ossified and increasing evidence of regenerate bone remodeling to more mature lamellar bone was noted. In conclusion, the utility of this rat model of distraction osteogenesis was demonstrated Less