自体颅骨粉末修复颅骨缺损的实验研究

目的 建立兔自体颅骨粉末移植修复颅骨缺损的动物模型,进行相关基础问题的研究,以更好地指导自体颅骨粉末移植修复颅骨缺损的临床工作.方法 新西兰大白兔30只,每只大白兔的顶部人工形成3个直径为1 cm颅骨全层缺损孔A、B、C.孔A为对照组;孔B、C作为实验组移植人工形成缺损时收集的骨粉,其中孔B在移植的骨粉上下面放置生物膜.术后4、8、12周各处死10只动物并取材分析.结果 孔A大部分由纤维结缔组织修复.孔 B早期就能迅速地以松质骨完全修复整个缺损,但松质骨后期的生长、改建、成熟过程比较缓慢.孔C新生骨更成熟,骨性修复慢且不完全.移植的骨粉被逐步吸收.早期新骨形成区可见大量的毛细血管分布.同一缺损,术后12周与术后4、8周形成的新骨钙含量差异有统计学意义(P＜0.05),同一时期,术后8、12周孔C形成的新骨钙含量比孔B的高,差异有统计学意义(P＜0.05).结论 新生骨的形成与血管的增生在时间和空间上有着密切的关系.生物膜可以促进移植的骨粉早期迅速形成初级松质骨.

Experimental study of repairing skull defect with autogeneous cranial bone dust

OBJECTIVE: To build animal model of skull defect for the basic research of skull defects reconstruction with autogeneous cranial bone dust and its relevance to the clinical application. METHODS: Three full-thickness parietal skull defects (A, B and C) were created in 30 new zealand white rabbits. The size of all the defects was 1 cm in diameter. The defect A was left untreated as control. Defects B and C were reconstructed with autogeneous cranial bone dust. Two pieces of pyroxylin membrane were placed on the top and bottom of the defect B. every 10 rabbits were killed for analysis at 4, 8, 12 weeks after operaton. RESULTS: Defect A was largely repaired with connective tissue. Defect B was repaired rapidly with newly formed cancellous bone in the early period, but the following process of the growth, remodeling and maturing of the newly-formed cancellous bone was slowly. The bone ingrowth in defect C was more mature, but could not repair the defect completely, especially in the central zone. The grafted bone dust was absorbed gradually. Active angiogenesis could be observed in the newly formed bone. For the same defect, new bone had a greater amount of calcium at 12 weeks than at 4 and 8 weeks after operation (P < 0.05). And the calcium content of new bone was higher in defect C than in defect B at 8, 12 weeks after operation (P < 0.05). CONCLUSIONS: The osteogenesis and angiogenesis are closely related to the time and location. The pyroxylin membrane can significantly promote the formation of cancellous bone in defect with autogeneous bone dust graft during the early period.