基于EBM制备钛支架的髋臼缺损支架设计与构建

Design and construction of acetabular defect scaffold based on titanium scaffold prepared by EBM

目的 通过电子束熔融技术(EBM)制造多孔钛支架,研究髋臼缺损支架的设计和构建技术。方法 采用计算机辅助设计(CAD),将3D打印多孔样品设计为0°/90°正交结构。3D打印的髋臼缺损支架由钛合金Ti-6Al-4V粉末加工而成。测量支架的大体形态、纤维直径和孔隙率。分别采用能量色散X射线光谱仪(EDS)和扫描电镜(SEM)对支架的表面元素分布、表面粗糙度进行观察。采用力学测试测量其载荷力、形变和弹性模量。对髋臼骨折患者进行计算机断层扫描(CT)检查,采用mimics软件将扫描数据进行重建模拟。结果 各支架的大体参数和微观结构参数与设计值比较差异均无统计学意义(P<0.05)。SEM图像显示,支架表面粗糙,适合细胞黏附和骨向内生长;力学测试结果显示,支架性能良好,弹性模量值在适合植入的松质骨和皮质骨区域。结论 CT与CAD逆向技术相结合可以完成复杂骨替代物的设计和制造,且成品具有所需的微观结构和物理性能。

Objective To manufacture porous titanium scaffolds by electron beam fusion technology(EBM),and study the design and construction technology of acetabular defect scaffolds.Methods Computeraided design(CAD) was used to design the 3D printed porous samples into 0°/90° orthogonal structures.The 3D-printed acetabular defect scaffold was machined from titanium alloy Ti-6Al-4V powder.The general morphology,fiber diameter and porosity of the scaffolds were measured.The surface element distribution and surface roughness of the scaffolds were observed by energy dispersive X-ray spectrometer(EDS) and scanning electron microscope(SEM),respectively.The load force,deformation and elastic modulus were measured by mechanical test.Computed tomography(CT) scans were performed on patients with acetabular fractures,and the scan data were reconstructed and simulated by mimics software.Results There were no significant differences between the general parameters and microstructure parameters of each stent compared with the design values(P<0.05).SEM images showed that the scaffold surface was rough,suitable for cell adhesion and bone ingrowth;The mechanical test results showed that the scaffold had good performance,and the elastic modulus values were in the cancellous and cortical bone regions suitable for implantation.Conclusion The combination of CT and CAD reverse technology can complete the design and manufacture of complex bone substitutes,and the finished product has the required microstructure and physical properties.