Corrosion Performance of Medical Titanium Alloys in Three Different Physiological Electrolytes
摘要
BACKGROUND: Titanium alloy implant has been widely used in the clinic. But there are few reports addressing on corrosion performance of medical titanium alloy dental implant, in particular in different physiological electrolytes. OBJECTIVE: To investigate the corrosion behaviors of medical titanium alloys in physiological saline, simulated saliva, and simulated body fluid. DESIGN, TIME AND SETTING: A randomized grouping, controlled observation was performed at the School of Stomatology, Lanzhou University and State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences between November 2008 and March 2009. MATERIALS: Medical titanium alloys (Ti-6Al-4V) were cut into 10 mm×10 mm×1 mm sheets and were randomly divided into 3 groups, with 10 sheets in each group. METHODS: Corrosion performance of titanium alloys in physiological saline, simulated saliva, and simulated body fluid was investigated using electrochemical measurements. Following electrochemical corrosion, surface morphologies and wettability of samples were also observed using scanning electron microscope and CA-A type contact angle tester. MAIN OUTCOME MEASURES: Tafel curve, surface morphology, and contact angle of medical titanium alloys in three physiological electrolytes after 4 days of electrochemical corrosion. RESULTS: The corrosion of titanium alloys was most severe in simulated saliva, followed by simulated body fluid, and mildest inphysiological saline. Scanning electron microscope results demonstrated that medical titanium alloy surface exhibited many holesafter corrosion by physiological saline, showed rough surface with a slightly changed number of holes after corrosion by simulatedbody fluid, and presented with an increased number of holes, with aperture greatly increased in some holes after corrosion by simulated saliva. The contact angles of titanium alloys were all reduced after corrosion of three electrolytes. CONCLUSION: The corrosion