口腔修复常用合金稳态电位的测定

Mensuration of corrosion potential of dental restorative alloys in common use

目的评价口腔修复常用合金的稳态电位及其发生腐蚀的倾向。方法测量五种修复常用合金在人工唾液中的初浸电位及24h后的稳态电位,并作统计学分析。结果得出五种材料的电偶序为:金合金、纯钛、钴铬合金、无锌银汞、含锌银汞。浸泡24h前后,金合金、纯钛、钴铬合金均为正移,而无锌银汞则负向移动。无锌银汞和含锌银汞的电位有显著性差异(P<0.05)。结论金合金、纯钛、钴铬合金是耐腐蚀性较好的材料。无法避免不同金属的同时应用时,应尽量选择电偶序中相邻的两种金属。建议临床使用无锌银汞代替含锌银汞。

Objective To evaluate corrosion potential and corrosion tendency of dental restorative alloys in common use. Methods Five alloys were marinated in a synthetic saliva solution. The potential of the alloys were recorded after the first five miniutes and the corrosion potential 24 hours later, and then statistical analysis was performed. Results The galvanic series of five kinds of alloys were obtain as followings： gold alloy, titanium, Co- Cr alloy, none - zinc amalgam, and zinc- containing amalgam. The statistical analysis indicated that the potential was changed prominently after being marinated in a synthetic saliva solution for 24 hours. The potential of gold alloy, titanium and Co- Cr alloy was increased, while none- zinc amalgam was decreased. Two kinds of amalgams showed significant a difference in potentials （ P 〈0.05）.Conclusion Gold, titanium and Co- Cr alloy exhibited a very high corrosion resistance. When dissimilar alloys were applied, a selection should be made between the alloys close together to galvanic series. Zinc - free amalgam was prefered instead of the zinc - containing amalgam in clinical settings.