A Study on Clinical Evaluation of Dental Casting Alloys

下面的实验是为了检查牙齿铸造合金在人类口腔中的变化。用四种牙铸造合金制作的<II类>铸造嵌体，在几名年轻人的磨牙上临时固定了1个月和3个月。临时胶结1、3个月后，用SEM观察各合金的表面变化，用EPMA分析各合金的化学成分。结果如下：(1)金合金和Ag-Pd-Cu-Au合金的表面变化不大，两种合金在口内的化学成分变化不大。(2)Ag-Sn-Zn合金的表面变化明显，近表面颊侧和龈侧变化明显。(3) 70Ni-19Cr合金在体内外均有显著变化，但在口腔内变化不大。目前正在研究造成这些结果的原因。

The following experiment was performed for the purpose of examining changes of dental casting alloys in human mouths. Class <II> cast inlays were fabricated with four kinds of dental casting alloys and had been temporarily fixed in molars of several young adults for 1 and 3 months. After 1 or 3 months temporary cementation, surface changes of each alloy were observed by SEM and the chemical composition was also analyzed by EPMA. The results are as follows.(1) Gold alloy and Ag-Pd-Cu-Au alloy showed very few changes in surface and there were few changes observed in chemical composition of both alloys in mouths.(2)Ag-Sn-Zn alloy was obviously changed in surface and remarkable changes were seen especially on buccal and gingival sides of proximal surface.(3)Though 70Ni-19Cr alloy showed remarkable changes in vitro and in vivo, few changes were observed in mouths. The cause of these results are now examining.