选择性激光烧结多孔钛种植体及其性能研究

Selective laser sintering and performances of porous titanium implants

目的分析选择性激光烧结(SLS)多孔钛种植体的机械性能及生物相容性,探讨其与壳聚糖(CS)/羟磷灰石(HA)复合涂层结合后的促骨结合作用。方法制备Ti6Al4V试件,部分试件表面进行CS/HA涂层处理;对试件进行扫描电子显微镜观察和机械性能检测;体外培养MC3T3-E1细胞,进行活/死细胞染色、甲基噻唑基四唑(MTT)及碱性磷酸酶(ALP)水平检测;将柱状螺纹种植体植入兔股骨髁部,分析其体内生物学性能。结果试件准弹性梯度随孔隙率增大而减小,孔隙率为30%时与皮质骨接近,70%时与松质骨接近;试件具有良好的生物相容性。复合CS/HA涂层后可促进MC3T3-E1细胞增殖、分化,有利于骨组织长入孔隙,形成良好的骨结合。结论多孔钛种植体具有良好的机械性能和生物相容性,与CS/HA涂层结合后具有骨诱导性,利于形成稳定的骨结合。

Objective This work aims to analyze the mechanical properties and biocompatibility of porous titanium（Ti） implants fabricated by selective laser sintering（SLS） and investigate the promotion of osseointegration by porous titanium implant combined with chitosan（CS）/hydroxyapatite（HA） composite coating. Methods Ti6 Al4 V specimens were prepared, and CS/HA composite coating was fabricated on the surface of a portion of the specimens. The mechanical properties of the samples were observed by scanning electron microscope. MC3 T3-E1 cells were cultured in vitro, and their biological properties in vitro were analyzed using live and dead viability cell staining method, methyl thiazolyl tetrazolium（MTT） staining, and alkaline phosphatase（ALP） level detection. The thread implant specimens were implanted in the femoral condyle of rabbits, and biological performance was evaluated in vivo. Results Quasi-elastic gradient of porous specimens decreased with increasing porosity, and the quasi-elastic gradient were close to cortical and cancellous bone when the porosities were 30% and 70%. The specimens showed good biocompatibility. Combined with CS/HA coating, the implants promoted the proliferation and differentiation of MC3 T3-E1 cells and facilitated the entry of bone tissue into pores and good osteogenesis. Conclusion The porous titanium implant exhibited favorable mechanical properties and biocompatibility. Combined with CS/HA coating, the implant exhibited bone inducibility, which leads to stable osteogenesis.