牵张成骨矫治腭裂的激光共聚焦荧光定量分析

Distraction osteogenesis for treatment of cleft palate——LSCM fluorescent labeling quantitive study

目的:利用激光共聚焦显微镜与计算机辅助荧光定量分析,研究牵张成骨术矫治腭裂新骨生成随时间间期不同的动态变化趋势,为临床矫治腭裂应用提供理论与实验依据。方法:以家猫20只为实验对象。其中18只动物建立人工腭裂实验模型。实验组(动物15只):应用牵张成骨术,以0.4mm×2次/d的速率牵张整复封闭其腭部组织缺损。术后第2、4、6、8及12周前6d以四环素肌注标记(30mg/kg)后各取材3只动物,标本制片后激光共聚焦显微镜观察荧光沉积并进行计算机定量分析,结果与实验对照组(动物3只)及空白对照组(动物2只)对比。结果:实验组不同时间间期标本的荧光强度平均值及其总量,显示出明确的动态变化规律,自2周组起,成骨活动明显活跃,到4周组达到顶峰,至8、12周组逐渐减弱,但仍显著高出无明显荧光沉积的空白和试验对照组。结论:应用牵张成骨术移动骨运送盘封闭组织缺损,牵张间隙逐渐被膜内成骨新骨生成修复,恢复了骨连续性。随时间间期的延长,新骨逐渐改建成熟。成骨活动呈现短期达到高峰后,逐步减弱的动态变化规律。

Objective：To study the new bone formation after distraction osteogenesis （DO） to repair cleft palate （CP） by laser scanning confocal microscope （LSCM） and quantitive image analysis. Methods： 20 cats were assigned randomly to 3 groups： Experimental group （ 15 cats） , the CP bone defects in hard palate were corrected with DO repair at the rate of 0.4 mm twice a day, till the transport disc （TD） reached the opposite edge across the defect region. The tetracycline labeling （30 mg/kg） were intramuscularly injected 6 days before specimens retrieval of each 3 cats at 2, 4, 6, 8 and 12 weeks after the completion of distraction. The sections were observed and analyzed by LSCM and quantitive image analysis. The results were then compared with empty control （2 cats） and experimental control group （3 cats）. Results： The data showed that active new bone formation were observed in 2 weeks and reached the summit in 4 weeks. The bone formation slowed down through 8 to 12 weeks but still significantly stronger than empty and experimental control groups in which no new bone growth were observed. Conclusion ：The hard palate bone defect is eventually reconstructed by DO repair and the distraction gap was filled with active de nove intramembranous osteogenesis. A consecutive dynamic curve of fluorescent labeling deposition implies active bone formation and remodeling is revealed.