Titanium and Its Alloys for Bone Implants

Titanium and its alloys have attracted considerable attention from the biomaterial engineering community and have achieved clinical success as a result of their outstanding properties. They are the metal of choice for important therapeutic devices, such as load-bearing orthopedic and dental implants. Today, β alloys that contain vital elements and exhibit a relatively low modulus of elasticity are particularly important. However, there are still problems that require improvement, especially regarding the surface properties of bone implants that lead to the potential failure of implants. The main complications include (i) poor surface bioactivity, which significantly prolongs the osseointegration process of long-term permanent bone implants, and (ii) implant-associated infections due to bacterial adherence and the growth of biofilms. Over the past several years, various strategies have been proposed to tailor the antimicrobial and simultaneous osteoconductive properties of titanium bone implants. Researchers have made various attempts to functionalize the surface properties of titanium-based biomaterials using physical and chemical surface treatments, coating deposition, and specific mechanical processes. This chapter provides an overview of current developments in titanium and its alloys, including the surface treatment approach, which is required for further successful application in biomedical engineering. The outstanding properties and limitations of titanium biomaterials, as well as current trends and challenges in surface treatment, are briefly discussed.