Additive manufacturing has facilitated the fabrication of orthopedic metal implants with interconnected pores. Recent reports have indicated that a pore size of 600 μm is beneficial for material-induced osteogenesis. However, the complete removal of the metal powder from such small pores of implants is extremely difficult especially in electron beam melting (EBM). We therefore developed a new type of Ti-6Al-4V implant with lattice-shaped interconnected pores measuring 880–1400 μm, which allowed for the easy removal of metal powder. This implant was fabricated by EBM and treated with NaOH, CaCl₂, heat, and water (ACaHW treatment) to render the metal surface bioactivity. In the present study, the mechanical and chemical property of the implants and the biocompatibility were evaluated. The SEM and micro-CT images demonstrated the 3D interconnectivity of the porous structures. The average porosity of the porous titanium implant was 57.5%. The implant showed maximum compressive load of 78.9 MPa and Young's modulus of 3.57 GPa which matches that of human cortical bone. ACaHW treatment of the porous Ti-6Al-4V implants induced apatite formation in simulated body fluid in vitro. The ACaHW-treated porous implants harvested from rabbit femoral bone showed direct bonding of bone to the metal surface without interposition of fibrous tissue. The porous ACaHW-treated implant had a higher affinity to the bone than the untreated one. The mechanical strength of implant fixation assessed using the push-out test was significantly higher in the ACaHW-treated implant than in untreated one. FE-SEM analysis and EDX mapping after push-out test of solid implants showed a lot of bone tissue patches on the surface of the ACaHW-treated implant. These results suggest that the new ACaHW-treated Ti-6Al-4V implant with lattice-shaped interconnected pores is a superior alternative to conventional materials for medical application.

增材制造促进了具有互连孔隙的骨科金属植入物的制造。最近的报道表明，600 μm 的孔径有利于材料诱导的成骨。然而，从植入物的这种小孔中完全去除金属粉末是极其困难的，尤其是在电子束熔化（EBM）中。因此，我们开发了一种新型 Ti-6Al-4V 植入物，其具有 880-1400 μm 的格子状互连孔，可以轻松去除金属粉末。该植入物由 EBM 制造并用 NaOH、CaCl _2处理、热和水（ACaHW 处理）以呈现金属表面的生物活性。在本研究中，评估了植入物的机械和化学性能以及生物相容性。SEM 和显微 CT 图像展示了多孔结构的 3D 互连性。多孔钛植入物的平均孔隙率为 57.5%。该植入物的最大压缩载荷为 78.9 MPa，杨氏模量为 3.57 GPa，与人类皮质骨相匹配。多孔Ti-6Al-4V植入物的ACaHW处理诱导体外模拟体液中磷灰石的形成. 从兔股骨采集的经 ACaHW 处理的多孔植入物显示出骨与金属表面的直接结合，而没有插入纤维组织。多孔 ACaHW 处理的植入物对骨骼的亲和力高于未经处理的植入物。使用推出试验评估的种植体固定的机械强度在经 ACaHW 处理的种植体中显着高于未经处理的种植体。实体种植体推出试验后的 FE-SEM 分析和 EDX 映射显示，经 ACaHW 处理的种植体表面存在大量骨组织斑块。这些结果表明，经过 ACaHW 处理的新型 Ti-6Al-4V 植入物具有格子状互连孔，是用于医疗应用的传统材料的优越替代品。