聚乳酸膜复合脱钙冻干异体骨修复下颌骨缺损

目的　探讨聚乳酸 (polylactic acid,PL A)膜复合脱钙冻干异体骨 (demineralized freeze- dried bone,DFDB)修复下颌骨缺损的可行性 ,比较单纯 PL A膜和 PL A膜复合 DFDB的骨修复能力。方法　在 2 4只日本大耳白兔双侧下颌骨下缘中份形成 1.0 cm× 0 .6 cm× 0 .4cm的矩形缺损。左侧缺损覆以 PL A膜 ,右侧缺损植入 DFDB后表面覆盖 PL A膜。术后 4、8、12周分期处死动物 ,取双侧下颌骨标本作大体观察 ,组织学观察 ,以及 X线片计算机灰度值分析。结果　 PL A膜复合 DFDB侧成骨活跃 ,成骨量高 ,计算机灰度值分析表明 ,术后 4、8周两侧缺损区内骨密度差异有显著性 (P<0 .0 1) ,复合材料侧骨密度较高。结论　 PL A/ DFDB复合材料是一种较理想的骨修复材料。

REPAIR OF MANDIBULAR DEFECT USING POLYLACTIC ACID MEMBRANE COMBINED WITH DEMINERALIZED FREEZE-DRIED FETAL BONE:AN EXPERIMENTAL STUDY IN RABBITS

Objective To investigate the possibility of repairing mandibular defect by using polylactic acid (PLA) membrane combined with demineralized freeze-dried bone (DFDB), and to evaluate the effection on bone repair of PLA membrane alone and PLA membrane combined with DFDB.Methods Bilateral mandibular defects were created in eighteen adult rabbits. Left defects covered with PLA membranes. Rigth defects were first filled with DFDB, and then were covered by PLA membraned. Animals were sacrified at 4, 8, 12 weeks of postoperation. The mandible specimens were assessed by gross inspection, light macroscopy, computer image analysis system.Results The defects repaired by PLA membrane combined with DFDB showed a higher activity of bone formation, and the quantities of newly-formed bone in right defects were much more than those in left defects, Statistic analysis on bone density showed a significent difference between the tow sides.Conclusion This study indicated that PLA membrane combined with DFDB was the more preferable compound materials for repairing mandibular defect.