Bioactive coatings deposited on titanium alloys

One of the ways to minimise corrosion products release from metallic implants to the surrounding tissue consists in applying a protective coating which may be functionalised with a bioactive material, able to generate a natural bonding to the living tissue. This work describes the development of a double layer coating obtained by the sol–gel technique containing bioactive glass, glass–ceramic or hydroxyapatite particles in hybrid methyl-triethoxisilane (MTES) and tetraethilorthosilicate (TEOS) sol on titanium alloy (ASTM F 67). Samples were electrochemically evaluated in a simulated body fluid (SBF). The application of the coating on the titanium alloy shows an improvement in the corrosion resistance in the tested period of time. This improvement could be due to the reaction of the particles with the physiological medium, which nucleates the formation of calcium phosphate crystals, and blocks the porosity of the coating.