目的:研究牵张成骨术整复腭裂骨缺损新骨生成过程中碱性磷酸酶(ALP)的表达与分布,探讨新骨生成与改建的变化规律。方法:家猫20只为实验对象。实验组:建立腭裂模型后以0.4mm/次,2次,d速率牵张整复腭部组织缺损。术后第2、4、6、8及12周分别处死3只动物,分析ALP在新骨组织中表达与分布。结果与实验对照组及空白对照组比较。结果:术后2周为成骨早期,即出现ALP高水平表达;术后4-6周为成骨中期,ALP强表达于成骨细胞膜及骨基质;术后8~12周则为成骨后期,ALP表达趋于静止。结论:牵张成骨法以新生骨组织修复腭裂骨缺损并最终改建成熟。
Objective: To study the expression and distribution characteristics of alkaline phosphatase (ALP) in new formed bone following distraction osteogenesis (DO) correction for cleft palate (CP) bone defect and to discuss the patterns of new bone formation and remodeling. Methods: Twenty cats were divided randomly into 3 groups. For the experimental group, the bone defects of hard palate in CP animal models were corrected by DO technique at the rate of 0.4mm twice per day, until the transport disc (TD) reached the opposite edge across the defect region. The specimens were retrieved at 2, 4, 6, 8 and 12 weeks after completion of distraction. The expression and distribution of ALP were analyzed by means of enzyme histochemistry, and the results were then compared with those of experimental control and empty control groups. Results: A dynamic trend of new bone formation and remodeling was revealed: early bone formation stage in 2 weeks with early high level ALP expression, intermediate stage through 4 to 6 weeks with highest level ALP expression and later remodeling stage of 8 to 12 weeks with normal ALP expression. Conclusion: The correction of DO for CP could get steadily new bone formation and gradually remodeling to mature bone structure.