常用口腔修复材料镍铬合金、钴铬合金和纯钛对可乐饮品的耐腐蚀性评价

目的：研究镍铬合金、钴铬合金和纯钛在可乐饮品中的电化学腐蚀行为，为临床修复中合金材料的选择提供依据。方法：以镍铬合金、钴铬合金和纯钛为研究对象分为3组，采用经典的三电极体系，测量各种金属合金在人工唾液和可乐中的自然腐蚀电位（Ecorr）和极化曲线，计算极化电阻（Rp）和腐蚀电流密度（Icorr），将所得数据进行统计分析。结果：镍铬合金、钴铬合金和纯钛在可乐中的Ecorr和Rp值小于人工唾液中的Ecorr和Rp值（P<0.05），3种修复材料在可乐中的Icorr值大于人工唾液中的Icorr值（P<0.05）。可乐中Ecorr和Rp值比较，镍铬合金最低，钴铬合金次之，纯钛最高（P<0.05）；Icorr值比较，镍铬合金最高，钴铬合金次之，纯钛最低（P<0.05）。结论：3种金属修复材料均在可乐中比在人工唾液中腐蚀速度快、耐腐蚀性差。在可乐中，纯钛的腐蚀速度最慢，耐腐蚀性最好，镍铬合金的耐腐蚀性最差；镍铬合金与钴铬合金的腐蚀速度均较快。

Evaluation on corrosion resistance of dental prosthetic materials Ni-Cr alloy, Co-Cr alloy and pure Ti in Cola

Objective To study the electrochemical corrosion of Ni-Cr alloy,Co-Cr alloy and pure titanium(Ti) in Cola,and to provide basis for choice of clinical materials.Methods Ni-Cr alloy,Co-Cr alloy and pure Ti were divided into 3 groups.The classic three-electrode system was used to measure the corrosion potential(Ecorr) and polarization curves,the polarization resistance(Rp),and corrosion current density(Icorr) in three groups in artificial saliva and Cola,and the results were analyzed by statistics.Results The values of Ecorr and Rp of Ni-Cr alloy,Co-Cr alloy and pure Ti in Cola were lower than those in artificial saliva(P<0.05),and the values of Icorr of them in Cola were higher than those in artificial saliva(P<0.05).In Cola,the values of Ecorr and Rp were Ni-Cr alloyCo-Cr alloy>pure Ti(P<0.05).Conclusion All of three kinds of metal materials have faster corrosion rate and poorer corrosion resistance in Cola than in artificial saliva.The corrosion rate of pure Ti in Cola is the slowest and the corrosion resistance is the best,while the corrosion rates of both Ni-Cr and Co-Cr in Cola are faster.