title: In vitro corrosion of dental Au-based casting alloys in polyvinylpyrrolidone-iodine solution.
abstract: The corrosion and tarnish behaviors of two Au-based casting alloys (ISO type 1 and type 4 Au alloys) and their constituent pure metals, Au, Ag, Cu, Pt, and Pd in a polyvinylpyrrolidone-iodine solution were examined. The two Au alloys actively corroded, and the main anodic reaction for both was dissolution of Au as AuI₂(-). The amount of Au released from the ISO type 1 Au alloy was significantly larger than that from the ISO type 4 Au alloy (P<0.05). Visible light spectrophotometry revealed that the type 1 alloy exhibited higher susceptibility to tarnishing than the type 4 alloy. The corrosion forms of the two Au alloys were found to be completely different, i.e., the type 1 alloy exhibited the corrosion attack over the entire exposed surface with a little irregularity whereas the type 4 alloy exhibited typical intergranular corrosion, which was caused by local cells produced by segregation of Pd and Pt.
authors.affiliation: Division of Fixed Prosthodontics and Oral Implantology, Department of Oral Rehabilitation, School of Dentistry, Health Sciences University of Hokkaido, 1757 Kanazawa, Tobetsu-cho, Ishikari-gun, Hokkaido 061-0293, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Takasusuki
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ida
authors.forename: Yukito
authors.initials: Y
authors.lastname: Hirose
authors.forename: Morio
authors.initials: M
authors.lastname: Ochi
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Endo
mesh_terms: D003300:Copper; D003343:Corrosion; D003735:Dental Casting Technique; D006046:Gold / Q000032:analysis; D006047:Gold Alloys / Q000737:chemistry*; D007101:Immersion; D008422:Materials Testing; D010165:Palladium; D010984:Platinum; D011206:Povidone-Iodine; D012834:Silver; D013499:Surface Properties
chemical_list: D006047:Gold Alloys; D012834:Silver; D010984:Platinum; D010165:Palladium; D006046:Gold; D003300:Copper; D011206:Povidone-Iodine