颅面部贴附植骨的实验研究

目的 探讨颅面骨表面贴附植骨吸收的内在机理。方法 实验用30只成年雄性新西兰白兔，随机均分成两组，采用自体颅有及肋骨块贴附移植于颅面骨表面。术后12周及24周分别取材，行大体观察，体积测量，组织学观察及电镜观察。结果 颅骨吸收少，移植骨皮质部在吸收改建过程中变化较大，颅骨或肋嘣骨胶原纤维的数量及排列24周比12周多而有规律。12周时，颅骨骨胶原纤维的数量及排列优于肋骨，而24周时，两种骨无差别，移植骨即使已经成活，内部构造还未完全成熟，移植骨体积进一步减少。结论 颅面部贴附植骨膜内化骨优于软骨内化骨，移植骨的皮质部是导致两种骨吸收不同的关键部位，移植骨的体积维持也与应力有关。

Experimental onlay implantation study on the cranium and face of rabbits: membranous versus endochondral bone

Objective\ To study the absorption mechanism of free bone autograft and compare the advantages of the membranous and endochondral bone autografts in rabbits. Methods\ Thirty adult male New Zealand white rabbits were randomly divided into two groups of fifteen each. Cranium graft or rib graft was implanted on each side of the snouts of the animal. The onlay grafts were harvested at 12th and 24th week. Then gross observation, volume measurement, histological study and scanning electron microscopical observation were performed. Results\ Cranium graft underwent less resorption than rib graft and the cortical bone underwent more resorption than cancellous bone. The number and arrangement of collagen fibrils at 24 weeks was more and better than that of 12 weeks. The collagen fibrils of the cranium graft were more numerous and regular than those of the rib graft at 12 weeks, but they were similar at 24 weeks. Although the grafts survived, their volume continued to decrease due to stress. Conclusions\ Membranous bone implanted on cranium of the rabbit is better than endochondral bone. Remodeling time of a cranium graft is shorter than a rib graft. The graft volume is also relating to stress.