Corrosion behavior of an oxide nanotube-coated β-type Ti-45Nb implant alloy in a simulated inflammatory solution

Oxide nanotube (ONT) layers were anodically grown on β-type Ti-45Nb and crystallized at 450 °C to anatase (Ti,Nb)O2. A corrosion analysis in normal and inflammatory phosphate buffered saline (PBS) comprised electrochemical polarization studies, metal release analysis, UV-Vis and EPR measurements. In inflammatory PBS with 0.5 wt% H2O2 (pH 5.0) amorphous ONT degraded, while crystallized ONT were most stable with lowest release. Their barrier-type behavior is attributed to their ordered crystalline nature and a fusion layer. As-ground Ti-45Nb surfaces were most reactive with highest corrosion and metal release rates. Mainly •OH radical-coordinated Ti(IV)-H2O2 complexes were detected in immersion solutions.