义齿清洁剂对3种活动义齿铸造支架常用金属腐蚀作用的研究

Research on Corrosion Resistance of Denture Cleanser to Three Metals for Removable Dental Applications

目的以电化学方法比较义齿清洁剂对活动义齿铸造用金属钴铬合金、钴铬钼合金、纯钛的腐蚀破坏程度。方法 2016年4—8月于南方医科大学深圳口腔医院将钴铬合金、钴铬钼合金、纯钛3种试件各10件分别浸泡于义齿清洁剂保丽净以及对照组自来水中。通过电化学线性扫描技术获得Tafel曲线,比较腐蚀电位(E_(corr))、腐蚀电流(I_(corr));以场发射扫描电镜观察金属表面形貌的变化,并对结果进行统计分析。结果纯钛在对照组自来水中的E_(corr)最正为(160.677±18.606)m V,在实验组清洁剂中的I_(corr)最小为(25.535±14.738)A,钴铬合金在清洁剂中的E_(corr)最负为(-72.933±15.367)mV,在自来水中I_(corr)最大为(98.199±17.421)A,3种材料间的E_(corr)、I_(corr)差异有统计学意义(P=0.000)。各合金在义齿清洁剂中的E_(corr)小于对照组(P=0.006),I_(corr)差异无统计学意义(P=0.361)。扫描电镜显示:腐蚀后,3种金属表面形貌均有差异,钴铬合金表面腐蚀凹陷较多,纯钛较少。结论钴铬合金在溶液中的腐蚀倾向最大,钴铬钼合金较小,纯钛最稳定。义齿清洁剂对支架金属的腐蚀性大于自来水。

Objective To compare the corrosion resistance property of Co-Cr alloy Co-Cr-Mo alloy and chemically pure Ti（CP Ti） in denture cleanser by means of electrochemical method. Methods The experiment was made from April to August 2016 in Shenzhen Stomatological Hospital of Southern Medical University. Three kinds of samples were separately soaked in denture cleanser and tap water. The electrochemical corrosion resistance behaviors were recorded by Tafel curves, the corrosion potential（Ecorr） and corrosion current（Icorr） were measured. The surface change of test samples was observed by scanning electron m icroscope（SEM）. Results The most positive score of Ecorrfor CP Ti in water was（160.677±18.606）m V,and the smallest score of Icorrfor CP Ti in denture cleanser was（25.535±14.738）A.The most negative score of Ecorrfor Co-Cr alloy in the denture cleanser is（-72.933±15.367）m V,and the biggest score of Icorrfor Co-Cr alloy in the water is（98.199±17.421）A. The scores of Ecorrand Ecorramong three materials in different liquids had statistical difference（P=0.000）. The Ecorrdenture cleansing agent of various alloys was lower than that in the control group（P=0.006）, but the difference in the Icorrwas not statistically significant（P=0.361）. Obvious changes were ob served on the morphology and phase before and after corrosion on Co-Cr alloy, CP Ti had least change. Conclusion Compared with the other two alloys, CP Ti is most resistant to corrosion.Denture cleanser may produce more effects on the corrosion than tap water.