生长期犬上颌骨缝牵张的实验研究

The empirical study of maxillary suture induced by sutural distraction osteogenesis in growing mongrel dogs

目的:了解上颌骨缝牵张成骨的骨质生成方式及不同牵引力对腭横缝组织影响。方法:以3～4月龄杂种犬21只为实验动物,实验组18只,空白对照组3只。实验组在两侧腭横缝及额上颌缝安置内置式镍钛合金牵引器。设计牵引器合力分别为:900g(A组)、1200g(B组)、1500g(C组)。牵引后5、10、15、20、30、40d切取腭横缝组织,行组织学观察。分光光度仪定量分析骨组织中碱性磷酸酶含量。结果:实验组上颌骨被成功前徙,组织学观察可见腭横缝改建活跃。牵引期内Ⅰ型胶原增多明显,Ⅱ、Ⅲ型胶原逐渐减弱。各组碱性磷酸酶增高明显,差异有显著性。结论:缝牵引是早期修复上颌发育不足的一种较佳方法;缝牵张成骨方式是膜内成骨;3种作用力差异有显著性,最佳作用力是1200g。

Objective： The purpose of this study was to evaluate the osteosis of maxilla sutural distraction osteogenesis （SDO） and its influence on surrounding tissue. Methods： 21 mongrel dogs about 3-4 months were used in the study. We placed the self-designed internal tiny nickel-titanium memory metal on the transverse palatine suture （TPS） and frontomaxillary suture （FS） of experimental dogs. Distraction force was devised as： 900g （A group）, 1200g （B group）, 1500g（C group）. 1 dog was respectively killed at different time points after distraction in 5, 10, 15, 20, 30 and 40days, then observe the histology and collagen changes. The expression of Alkaline phosphatase （AKP） in new formed bone was semiquantiative analysis with spectrophotometer. Results： The maxillary bone of experimental dogs showed advancement in different degree. We did not find cartilage cells in histology. When the time goes by, the I type collagen in sutural tissue and new bone increases, and the II and III type collagen decrease little by little. And the difference of AKP content is significant between experimental groups. Conclusion： SDO is a kind of simple, convenience, safe, reliability, effective operative method to extend the maxillary bone of dogs in development stage. The bone formation of SDO is intramembranons ossification. The optimization force of SDO is 1200g.