在移植骨上延期种植的实验研究

目的论证冷冻自体下颌骨复合髂骨移植后延期种植的可行性。方法16只成年雄性杂种狗，制备下颌骨双侧骨缺损，左侧行冷冻自体下颌骨骨块的原位再植并结合髂骨松质骨移植，即复合移植组（composite transplantation group，CTG），右侧缺损行自体髂骨块移植即髂骨移植组（iliac transplantation group，ITG），术后3个月分别在两类骨块上植入IMZ TPS种植体，种植体植入后3、6、9、12周分别处死4只动物取材，采用数字化X线片对种植体与颌骨结合界面进行灰度定量分析，组织学观察种植体．骨结合情况。结果各期种植体周围均未见吸收性骨质密度减低影像。骨一种植体界面灰度定量分析显示，种植体植入两类移植骨3、6和9周时，其界面骨质密度改变差别明显，复合移植组明显优于髂骨移植组；种植体植入12周时，两组界面骨质已无明显差别，两类移植骨均与种植体有良好的骨结合，其骨愈合方式基本相同。结论冷冻自体下颌骨复合移植修复下颌骨缺损并延期植入牙种植体后，二者可形成良好的骨结合。

Experimental study of delayed implantation on bone grafts

OBJECTIVE: To explore the feasibility of transplantation of frozen autogenous mandible with delayed implantation. METHODS: Operations were performed to create two defects in the bilateral mandible of 16 dogs. The left defect was grafted by composite transplantation of frozen autogenous mandible (immersed in -196 degrees C liquid nitrogen) with fresh cancellous ilium (composite transplantation group, CTG). The right defect was grafted by fresh ilium (iliac transplantation group, ITG). Three months after transplantation one IMZ TPS dental implant was placed into the graft of each side. At 3, 6, 9, 12 weeks postoperatively, 4 animals were sacrificed respectively and the grafts with dental implant were harvested for gross observation, X-Ray examination and histological evaluation to compare peri-implant bone healing between composite transplantation group and iliac transplantation group. RESULTS: There was no absorbing bone density reducing image of peri-implant at each stage. The quantified X-Ray gray extent displayed obvious variation of interfacial bone density between two kinds of grafts at 3 weeks, 6 weeks and 9 weeks after implantation. The composite transplantation group obviously surpassed the iliac transplantation group. At 12 weeks after the implantation, there was no significant difference between the peri-implant bones of both sides. There was satisfactory osseointegration between the implants and the two kinds of grafts. The healing style of peri-implant bone was similar. CONCLUSIONS: Good osseointegration was performed between the implant and the composite transplantation of frozen autogenous mandible following delayed implantation.