骨诱导性磷酸钙陶瓷为支架的组织工程骨修复狗下颌骨箱状缺损

背景:应用不外加生长因子或细胞而具有骨诱导性的生物材料,在非骨部位构建骨移植物,即体内组织工程骨,其在修复箱状及节段性骨缺损方面,具有更可行的前景.目的:采用骨诱导性钙磷陶瓷材料构建体内组织工程化类骨移植物,探索其应用于修复实验动物下颌骨箱状骨缺损的可行性.方法:以骨诱导性磷酸钙陶瓷材料为支架植入狗肌肉内构建体内组织工程骨,同期在狗自体下颌骨左右两侧各拔除牙弓中段牙2颗,形成约20 mm无牙区.8周后在无牙区形成箱状缺损,同期取出支架即刻移植入一侧自体下颌骨缺损区,对侧骨缺损区直接移植入未经体内构建的磷酸钙陶瓷作为对照.结果与结论:经肌肉内构建的体内组织工程骨移植物的力学性能较单纯磷酸钙陶瓷有明显提高.颌骨缺损区的核吸收强度明显强于对照区,其移植物内长入的骨组织较多,两者的成骨面积差异有非常显著性意义(P < 0.01).说明在修复颌骨大范围缺损中,体内组织工程骨移植物较单纯骨磷酸钙陶瓷替代材料表现出明显的力学和生物学优势,修复效果显著,有良好的应用前景.

Application of tissue-engineered bone with osteoinductive calcium phosphate ceramic scaffold for mandible boxlike bone defect repair

BACKGROUND: Intrinsic osteoinductive biomaterials with no external growth factors or cells to build bone graft in non-bone parts is consider as in vivo bone tissue engineering which has feasible prospects in repair boxlike and segmental bone defect. OBJECTIVE: To investigate the feasibility of using in vivo tissue engineered (TE) bone with osteoinductive calcium phosphate (Ca-P) ceramic to repair boxlike mandibular defect. METHODS: The TE bone graft was constructed in vivo by implanting osteoinductive Ca-P ceramics in the femoral muscles of dog for 8 weeks, at the same period, 2 middle arch teeth in dog mandible from the right and left sides were removed for the formation of no teeth area with 20 mm. After 8 weeks, boxlike bone defect were created in two side of no teeth area and the TE bone graft in the femoral muscles was removed, then was transplanted to repair the defect, while in the opposite side of the mandibular defect was transplanted with the construction not in vivo as control. RESULTS AND CONCLUSION: Mechanical of in vivo tissue-engineered bone grafts constructed in the femoral muscles was improved than simple Ca-P ceramic. Nuclear absorption intensity in mandibular defect area in was stronger than that in control area. Mandibular defect area had many bone tissues ingrowth. There were significant differences of bone area between mandibular defect area and control area. Therefore, it is feasible to construct a live bone graft of osteoinductive Ca-P ceramics in vivo which have obvious advantages of the mechanical and significant biological repair effect to repair a mandibular bone defect as compared with simple calcium phosphate ceramic substitute materials.