title: Evaluation of corrosion resistance of implant-use Ti-Zr binary alloys with a range of compositions.
abstract: Although titanium-zirconium (Ti-Zr) alloy has been adopted for clinical applications, the ideal proportion of Zr in the alloy has not been identified. In this study, we investigated the biocompatibility of Ti-Zr alloy by evaluating its corrosion resistance to better understand whether there is an optimal range or value of Zr proportion in the alloy. We prepared pure Ti, Ti-30Zr, Ti-50Zr, Ti-70Zr, and pure Zr (mol% of Zr) samples and subjected them to anodic polarization and immersion tests in a lactic acid + sodium chloride (NaCl) solution and artificial saliva. We observed pitting corrosion in the Ti-70Zr and Zr after exposure to both solutions. After the immersion test, we found that pure Ti exhibited the greatest degree of dissolution in the lactic acid + NaCl solution, with the addition of Zr dramatically reducing Ti ion dissolution, with the reduction ultimately exceeding 90% in the case of the Ti-30Zr. Hence, although the localized corrosion resistance under severe conditions was compromised when the Zr content was more than 70%, metal ion release reduced owing to Zr addition and the corresponding formation of a stable passive layer. The results suggest that Ti-30Zr or a Zr proportion of less than 50% would offer an ideal level of corrosion resistance for clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 73-79, 2018.
authors.affiliation: Removable Partial Prosthodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
authors.forename: Teisuke
authors.initials: T
authors.lastname: Akimoto
authors.affiliation: Removable Partial Prosthodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ueno
authors.affiliation: Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-0062, Japan.|Graduate School of Engineering, The University of Tokyo, Bunyko, Tokyo, 113-8656, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Tsutsumi
authors.affiliation: Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-0062, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Doi
authors.affiliation: Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-0062, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Hanawa
authors.affiliation: Removable Partial Prosthodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Wakabayashi
mesh_terms: D000497:Alloys / Q000737:chemistry*; D003343:Corrosion; D019344:Lactic Acid / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry*
chemical_list: D000497:Alloys; C000599177:Ti-Zr alloy; D019344:Lactic Acid; D012965:Sodium Chloride
keywords: anodic polarization test; corrosion resistance; immersion test; implant; titanium-zirconium alloy