Metal surface oxidation and surface interactions

In this chapter we discuss the main aspects of metal oxides in metallic biomaterials, with a special emphasis on titanium. Basic chemico- physical principles, in terms of titanium oxide layer ability to promote specific interactions in biological environments, are discussed. Further on, the theoretical approaches to describe the surface behaviour at atomistic level are reviewed, together with the hydration studies and protein adsorption at the surface of the titanium dioxide polymorphs. We then critically discuss the role of chemical and electrochemical surface modification technologies, aimed at modifying TiO2 structure, morphology and chemistry to tailor in vivo biological response. A perspective analysis of the correlation between theoretical studies and metal oxide surface modifications is finally offered, discussing their strengths and weaknesses and emphasizing their role as a powerful design tool for a new generation of implantable devices in which metal oxide surfaces can be tuned to yield a specific biological response.