The interface between the implant and host bone plays a key role in maintaining primary and long-term stability of the implants. Surface modification of implant can enhance bone ingrowth and increase bone formation to create firm osseointegration between the implant and host bone and reduce the risk of implant losing. This paper mainly focuses on the fabricating of 3-dimensiona interconnected porous titanium by sintering of Ti6Al4V powders, which could be processed to the surface of the implant shaft and was integrated with bone morphogenetic proteins (BMPs). The structure and mechanical property of porous Ti6Al4V was observed and tested. Implant shaft with surface of porous titanium was implanted into the femoral medullary cavity of dog after combining with BMPs. The results showed that the structure and elastic modulus of 3D interconnected porous titanium was similar to cancellous bone; porous titanium combined with BMP was found to have large amount of fibrous tissue with fibroblastic cells; bone formation was significantly greater in 6 weeks postoperatively than in 3 weeks after operation. Porous titanium fabricated by powders sintering and combined with BMPs could induce tissue formation and increase bone formation to create firm osseointegration between the implant and host bone. 1. Introduction The hip joint is a spherical joint between the femoral head and the acetabulum in the pelvis. It is a diarthrosis or synovial joint wrapped in a capsule that contains the synovial fluid (SF). The hip joint can transmit high dynamic loads and accommodate a wide range of movements because of the presence of the SF and the ball-in-socket geometry. Though its remarkable characteristics, the hip joint can be affected, more often in aged people, by chronic pain and diseases such as osteoarthritis, rheumatoid arthritis, bone tumors, or traumas. In these cases, the best clinical solution is the total hip replacement, a surgical procedure that replaces the unhealthy hip joint with an implant, preserving the synovial capsule [1–3]. Metallic materials are widely used for joint replacement and orthopedic and dental implants. Metals are more suitable for loading-bearing applications when compared with ceramics or polymeric materials because of their excellent mechanical property. Among various metallic biomaterials, titanium and its alloys are the most attractive metallic biomaterials for orthopedic and dental implants due to their excellent mechanical properties, biocompatibility, processability, and good corrosion resistance in recent years. However, a major problem
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