壳聚糖纤维/磷酸钙骨水泥复合材料人工骨的力学性能

Mechanical Performance of Chitosan Fiber/Calcium Phosphate Cement Composite for Artificial Bone

提出采用壳聚糖纤维为增强体来改善磷酸钙骨水泥的力学性能,并模仿天然骨的结构制造具有同心圆结构的壳聚糖纤维/骨水泥复合材料人工骨。利用快速成形技术制造精密树脂模具,在模具的支持下制备两种规格的人工骨((?)20 mm×20 mm和(?)10 mm×20 mm),分别进行人工骨初始强度试验和体内强度试验。试验表明,由于纤维的存在,复合材料人工骨的初始强度为11～26 MPa,明显高于磷酸钙骨水泥4～10 MPa的强度;同时在犬股骨髁缺损修复的过程中,随着壳聚糖纤维的消失而逐渐形成的多孔结构和孔隙并没有降低复合材料人工骨的力学性能,而是通过形成的多孔结构促进骨长入来维持人工骨的强度,使得人工骨多孔结构与强度的矛盾关系得到缓解。

Chitosan fiber （CF） as reinforcement to improve the mechanical properties of calcium phosphate cement （CPC） is presented, while CF/CPC composite artificial bone with concentric fiber structure that mimics the microstructure of natural bone is fabricated. Special resin precise moulds produced by rapid prototyping （RP） are used to prepare two types of cylindrical CF/CPC artificial bones （Ф20 mm × 20 mm and Ф10 mm × 20 mm）, which are evaluated respectively by initial intensity and in vivo intensity experiment. The initial strength of the CF/CPC composite specimens is 11-26 MPa, significantly higher than CPC＇s 4 -10 MPa. And the porous structure and the macropores, which are gradually achieved for bone growth with the dissolution of chitosan fibers during the canine condyle defect repairing, do not lower mechanical properties of the implanted CF/CPC composite artificial bone. In conclusion, the existence of chitosan fibers can achieve the needed initial strength for CPC while tissue regeneration is occurring, and create porous structure for bone growth to turn to strengthen the implant when the fiber is dissolved, and this alleviate s the conflict between artificial bone＇s porous structure and its strength.