Fukushima Osamu, Yoneyama Takayuki, Doi Hisashi, Hanawa Takao
Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Japan.
Dent Mater J. 2006 Mar;25(1):151-60. doi: 10.4012/dmj.25.151.
Ti-Ni alloy has been increasingly applied to medical and dental devices, such as coronary stents and orthodontic wires. This alloy contains nickel, which is known to give rise to cytotoxicity, metal allergy, and carcinogenicity. Therefore, the purpose of this study was to improve the corrosion resistance of Ti-Ni alloy by electrolytic treatment, whereby investigation was carried out using different acidic electrolyte compositions. As a result, specimens electrolyzed with lactic acid, water, and glycerol were found to show higher corrosion potential and release lower amount of titanium and nickel ions than mechanical-polished specimens (p<0.05). With the electrolytic treatment, nickel concentration in the surface oxide layer of Ti-Ni alloy decreased, and the thickness of the surface oxide layer increased. Based on the results of this study, it was shown that electrolytic treatment with suitable electrolyte could improve the corrosion resistance of Ti-Ni alloy, which is effective to produce medical and dental devices that utilize shape memory effect or superelasticity with better biocompatibility.
钛镍合金已越来越多地应用于医疗和牙科器械，如冠状动脉支架和正畸钢丝。这种合金含有镍，已知镍会引起细胞毒性、金属过敏和致癌性。因此，本研究的目的是通过电解处理提高钛镍合金的耐腐蚀性，从而使用不同的酸性电解质成分进行研究。结果发现，用乳酸、水和甘油进行电解的试样比机械抛光的试样显示出更高的腐蚀电位，并且释放的钛和镍离子量更低（p<0.05）。通过电解处理，钛镍合金表面氧化层中的镍浓度降低，表面氧化层的厚度增加。基于本研究的结果，表明用合适的电解质进行电解处理可以提高钛镍合金的耐腐蚀性，这对于生产利用形状记忆效应或超弹性且具有更好生物相容性的医疗和牙科器械是有效的。
