Titanium foams for biomedical applications: a review

Metals are the oldest of biomedical implant materials and metallic alloys remain the material of choice for applications involving hard tissue replacement. Ti alloy scaffolds are deemed the best among all the metallic alloys. Recently, porous Ti alloy scaffolds have received increasing attention over other metallic counterparts, including monolithic alloys, due to advantages associated with an open porous structure. The main advantages of open porous structures are a low Young's moduli and enhanced bone ingrowth leading to better fixation with the host tissue. In this paper, the authors first review the suitability of Ti for biomedical applications and then explore the methods for producing highly porous Ti foams. The methods are assessed based on their ability to produce a macro-micro-structure appropriate for biomedical applications. The article concludes with a future outlook on porous Ti production.