目的探讨基于快速成型技术立体编织仿生大段人工骨的成骨性能、修复效果及可能的修复机制。方法以计算机辅助设计(CAD)设计人工骨的微结构,用三维立体编织技术将可吸收手术缝合线编织成人工骨微结构支架的负型,在缝线上涂敷Ⅰ型胶原蛋白控制人工骨的孔道尺寸,在编织物内充填复合rh—BMP2的自固化磷酸钙骨水泥(CPC),将其移植到家犬桡骨25mm完全骨膜.骨缺损区,第4、8、16和24周进行观察,研究骨缺损的修复情况。结果大体观察发现,早期Ⅰ型胶原蛋白溶解、消失。组织学观察发现,术后4周可见新生血管和骨岛,8周可见大量巢状软骨细胞团及编织骨,16周骨岛连接成片,24周新生骨组织呈数个连续过渡的条带样分布区。随植入时间延长,植入体中钙催比值趋向于自体皮质骨。结论3DBF人工骨具备骨缺损修复过程中组织再生所需的微结构及相应的生物学行为。
Objective To investigate the ability of osteogenesis, repaired effects and possible mechanism of 3-D braiding artificial bone fabricating the micro-frame work in an approach of RP technology. Methods CAD was adopted to design the microstructure of the artificial bone,an absorbable medical suture framework was constructed with 3-D braiding technology to play as the micro-scaffold model of the artificial bone, the collagen type Ⅰ was spread on the suture surface to control the size of the micro-pipes, and the calcium phosphate cement combined with rh-BMP2 was filled into the module to form the artificial bone with micro-holes after itself crystallized. The combined biomaterial was transplanted to total segmental periosteum-bone defect of 25 mm in the canine radius and observed 4,8,16 and 24 weeks after operation respectively. Results In gross observation, the collagen Ⅰ began to be dissolved and almost dispeared in early time. In histological examination of 4 weeks after operation, new born blood vessel and bone island were found,and 8 weeks after operation,lots of nest-like chondrocytes mass and woven bone were found,and the new bone islands were connected in together 12 weeks after operation. Twenty-four weeks after operation, the newly born bone arranged in type of various bands in subsequent transition was found. Furthermore, the ratio of calcium to phosphorus in the transplants tended to approach that in the host cortical bone along with the period of time after operation. Conclusion The microtubule structure 3DBF artificial bone simulated is suitable for tissue regeneration during the repair process of bone defects, thus the proper biological behaviors are confirmed.