title: Low elastic modulus Ti-Ta alloys for load-bearing permanent implants: enhancing the biodegradation resistance by electrochemical surface engineering.
abstract: In this study, the in vitro degradation behaviour of titanium-tantalum (Ti-Ta) alloys (10-30 wt.% Ta) was investigated and compared with conventional implant materials, i.e., commercially pure titanium (Cp-Ti) and titanium-aluminium-vanadium (Ti6Al4V) alloy. Among the three Ti-Ta alloys studied, the Ti20Ta (6.3×10(-4) mm/y) exhibited the lowest degradation rate, followed by Ti30Ta (1.2×10(-3) mm/y) and Ti10Ta (1.4×10(-3) mm/y). All the Ti-Ta alloys exhibited lower degradation rate than that of Cp-Ti (1.8×10(-3) mm/y), which suggests that Ta addition to Ti is beneficial. As compared to Ti6Al4V alloy (8.1×10(-4) mm/y), the degradation rate of Ti20Ta alloy was lower by ~22%. However, the Ti30Ta alloy, which has closer elastic modulus to that of natural bone, showed ~48% higher degradation rate than that of Ti6Al4V alloy. Hence, to improve the degradation performance of Ti30Ta alloy, an intermediate thin porous layer was formed electrochemically on the alloy followed by calcium phosphate (CaP) electrodeposition. The coated Ti30Ta alloy (3.8×10(-3) mm/y) showed ~53% lower degradation rate than that of Ti6Al4V alloy. Thus, the study suggests that CaP coated Ti30Ta alloy can be a viable material for load-bearing permanent implants.
authors.affiliation: Biomaterials and Engineering Materials (BEM) Laboratory, School of Engineering and Physical Sciences, James Cook University, Townsville, Queensland 4811, Australia.
authors.forename: Jazmin
authors.initials: J
authors.lastname: Kesteven
authors.affiliation: Biomaterials and Engineering Materials (BEM) Laboratory, School of Engineering and Physical Sciences, James Cook University, Townsville, Queensland 4811, Australia. Electronic address: bobby.mathan@jcu.edu.au.
authors.forename: M Bobby
authors.initials: MB
authors.lastname: Kannan
authors.affiliation: Biomaterials and Engineering Materials (BEM) Laboratory, School of Engineering and Physical Sciences, James Cook University, Townsville, Queensland 4811, Australia.
authors.forename: Rhys
authors.initials: R
authors.lastname: Walter
authors.affiliation: Biomaterials and Engineering Materials (BEM) Laboratory, School of Engineering and Physical Sciences, James Cook University, Townsville, Queensland 4811, Australia.
authors.forename: Hadis
authors.initials: H
authors.lastname: Khakbaz
authors.affiliation: Department of Dental Materials, Chosun University, Gwangju 501-759, South Korea.
authors.forename: Han-Choel
authors.initials: HC
authors.lastname: Choe
mesh_terms: D000497:Alloys; D001672:Biocompatible Materials; D055664:Electrochemical Techniques / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D019736:Prostheses and Implants; D013499:Surface Properties; D013635:Tantalum / Q000737:chemistry; D014025:Titanium / Q000737:chemistry
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; D013635:Tantalum; D014025:Titanium
keywords: Anodization; Biomaterials; Calcium phosphate; Degradation; Tantalum; Titanium