医用镍钛形状记忆合金的表面改性及生物相容性

背景:近等原子比镍钛形状记忆合金以其8%的形变率、上万次的循环次数、优异的抗腐蚀性以及低弹性模量、低磁和射线不透性,成为理想的生物植入材料之一。目的:论述医用近等原子比镍钛形状记忆合金的表面改性及其生物相容性。方法:由第一作者检索1990/2008 PubMed数据库及万方数据库有关医用镍钛形状记忆合金的表面化学处理、化学修饰及植入生物组织后镍离子溶出等方面的文献。结果与结论:近等原子比镍钛形状记忆合金中含镍量较高,对其是否能在人体内安全地长期使用一直存有争议,合金表面改性是提高植入物的生物相容性、解决这一问题的有效途径。镍钛记忆合金可通过表面改性降低镍离子释放,提高生物相容性,为此,国内外学者均做了大量研究工作。但当前对于含镍钛医用合金置入后体内镍离子的代谢过程方面的研究尚不够系统和全面。

Surface modification and biocompatibility of medical nickel-titanium shape memory alloys

BACKGROUND:Near-equiatomic nickel-titanium shape memory alloy can be used as a type of ideal biological implant material based on its deformation rate of 8%,million times in the number of cycles,excellent corrosion resistance and low elastic modulus,low magnetism,and radiopacity.OBJECTIVE:To discuss the surface modification and biocompatibility of the medical near-equiatomic nickel-titanium shape memory alloy.METHODS:A computer-based online search was performed in PubMed database and Wanfang database for literatures from January 1990 to December 2008 related to surface chemical treatment and chemical modification of medical nickel-titanium shape memory alloy and dissolvability of nickel after implantation of the alloy into biological tissues.RESULTS AND CONCLUSION:Near-equiatomic nickel-titanium shape memory alloy has high nickel content.However,there has been controversy about the safety after long term implantation of the alloy in vivo.Alloy surface modification is an effective way to improve the biocompatibility of implants.The release of Ni ion can be decreased by surface modification of nickel-titanium shape memory alloy,and many related research works have been done by domestic and overseas scholars.However,studies about the metabolic process of Ni ion in vivo after implantation of nickel-titanium alloy are not comprehensive and systematic.