矿化胶原改性骨水泥的制备及生物力学测定

Preparation and biomechanical properties of polymethyl methacrylate modified by mineralized collagen

目的基于矿化胶原(MC)对聚甲基丙烯酸甲酯(PMMA)进行改性,提高其在骨修复领域应用的可行性。方法将不同粒径MC(<200μm、200~300μm、300~400μm、400~500μm)按照5 wt%、10 wt%、15 wt%、20 wt%的含量加入到PMMA骨水泥,制备不同粒径及含量的复合骨水泥。通过工作特性、抗压强度、抗弯强度、压缩模量、弹性模量测试,评估MC/PMMA复合骨水泥的生物力学性能,确定最佳性能的复合骨水泥比例。结果复合骨水泥混合时间30 s,等待时间2~5 min,工作时间5~12 min,固化时间10~20 min;不同粒径MC(<200μm、200~300μm、300~400μm、400~500μm)复合骨水泥,在不同含量(5 wt%、10 wt%、15 wt%、20 wt%)下其抗压强度均可保持在70 MPa以上,对PMMA骨水泥的抗压强度影响不大。含量15 wt%、粒径300~400μm MC/PMMA复合骨水泥的抗压强度90 MPa,抗弯强度50 MPa,压缩模量1.2 GPa,弹性模量较Osteopal V和Mendec Spine骨水泥明显降低,且与人体松质骨的弹性模量相匹配。结论MC在保持PMMA机械强度的同时,可降低其弹性模量,含量15 wt%、粒径300~400μm MC/PMMA骨水泥的工作特性、抗压和抗弯强度、弹性模量符合国际标准和临床使用要求。

Objective To extend the application of polymethyl methacrylate(PMMA)in the field of bone repair by adding mineralized collagen(MC)for modification.Methods The different contents and particle sizes of MC/PMMA modified bone cement were prepared by adding different concentrations of MC(5 wt%,10 wt%,15 wt%,20 wt%).Working characteristics,compressive strength test,bending strength test and compression modulus test were obtained.The mechanical properties of modified bone cement were evaluated and the composite cement ratio with the best performance was determined.Results The working characteristics of MC/PMMA was as follows:The mixing time was 30 s,the waiting time was 2-5 min,the working time was 5-12 min,and the curing time was 10-20 min.MC had little effect on the compressive strength of PMMA,and the compressive strength of MC/PMMA can be kept above 70 MPa in a certain range(content:5 wt%,10 wt%,15 wt%,20 wt%;particle size:<200μm,200-300μm,300-400μm,400-500μm).The compressive strength,flexural strength and compressive modulus of MC/PMMA(15wt%,300-400μm in diameter)were 90 MPa,50 MPa and 1.2 GPa respectively.The elastic modulus of MC/PMMA was significantly lower than that of Osteopal V and Mendec Spine,and matched with the elastic modulus of human bone.Conclusion While maintaining the mechanical strength of PMMA,MC can reduce its elastic modulus.The working characteristics,compressive and flexural strength and elastic modulus of MC/PMMA bone cement with a content of 15 wt%and a particle size of 300-400μm meet international standards and clinical application requirements.