Corrosion of titanium for biomedical applications

[摘要] Ti has been widely used in biomedical fields since the 1950s because of biocompatibility, corrosion resistance and suitable mechanical properties. However, corrosion-related failures of Ti implants are observed. Ti corrosion products are reported to induce unfavourable biological responses, which may lead to failures of Ti implants.Corrosion of three grades of Ti (CP-Ti Grade2, CP-Ti Grade4 and Ti6Al4V) in simulated peri-implant environments was investigated by solution analysis, surface analysis and electrochemical tests.Lipopolysaccharide, a component of bacterial cell walls and a mediator of peri-implant inflammation, was observed to enhance Ti corrosion in slightly acidic and neutral conditions (pH 4-7) whilst it inhibited Ti dissolution in highly acidic environments (pH 2).Both albumin, an abundant protein, and H\(_2\)O\(_2\), an important inflammation product, influenced corrosion of Ti6Al4V and the co-existence of both species considerably enhanced Ti release than either species in isolation. The β phase of Ti6Al4V was preferentially attacked in H\(_2\)O\(_2\).The presence of an early coloniser of dental implants Streptococcus sanguinis and human neutrophils, abundant immune cells, promoted Ti release.Mechanically-assisted crevice corrosion simulation was demonstrated with development of aggressive crevice chemistry. Albumin decreased the abrasion charge of Ti6Al4V while LPS and H2O2 did not show a measurable change.

[发布机构] University:University of Birmingham;Department:School of Metallurgy and Materials

[关键词] R Medicine;R Medicine (General)