The relation between electrochemical tests and in vitro evaluation of titanium alloy biocompatibility

摘要

In this paper, the electrochemical behaviour of the titanium and Ti-6Al-7Nb alloy in artificial saliva (Tani&Zucchi and Carter-Brugirard), ion release tests and in vitro biocompatibility of human osteoblasts (HOB) were studied. Titanium and its implant Ti-6Al-7Nb alloy present self-passivation and very stable passive films in Tani&Zucchi artificial saliva of pH=2.5; 5; 6.7; 9; the total quantity of ions released in the artificial saliva and corrosion rates are very low, proving a very good corrosion resistance and very low toxicity. In undoped and doped Carter-Brugirard saliva, the open circuit potentials have highly electropositive values, denoting passive state and good stability; the open circuit potential gradients, simulating the non-uniformity of the saliva composition, show very low values, no danger for the implant integrity. The in vitro cytotoxicity of Ti-6Al-7Nb alloy was evaluated on the basis of cell morphology and cell viability. The results obtained revealed a high biocompatibility between HOB and Ti-6Al-7Nb alloy.