Studies on Gallium Alloy for Dental Use

镓合金由液态的Ga-In-Sn-Ag合金和Ag-Sn-Cu-Pd-Zn合金组成，作为球形粉末代替牙科用汞齐.以高铜汞齐（Spherical-D）为对照，对镓合金的理化性能进行了比较。镓合金在0.05%HCl、1%乳酸溶液中的抗压强度和径向抗拉强度高于汞合金，但腐蚀失重略高于汞合金。还有镓合金在1%NaCl和人工唾液中的腐蚀失重与汞齐相同.镓的生物学评价。合金（1）镓合金与汞合金的致突变性比较。两组比较，Rec和艾姆斯试验无显著性差异。(2)组织培养试验：与镓、合金、银汞合金、纯镍比较，细胞培养试验无显著性差异。(3)对132颗乳牙用镓合金与银汞合金作对照，观察牙髓反应。两组相比，牙髓反应无显著差异。(4)镓合金对人体皮肤的原发性刺激性不明显.临床观察对32颗乳磨牙Ⅰ类洞用镓合金充填进行3个月临床观察。在第13例和第4例中观察到轻微的表面粗糙度，但在3个月后未发现脱落和裂纹。通过对患者第二次就诊时出现变色、表面粗糙和台阶的病例进行重新抛光，镓合金的临床使用似乎没有问题。

Gallium Alloy consist of liquid alloy of Ga-In-Sn-Ag and Ag-Sn-Cu-Pd-Zn alloy as spherical powder were used instead of dental amalgam.1. Physical and chemical properties to gallium alloy as compared with that of high copper amalgam (Spherical-D) as a control. The gallium alloy showed more compressive strength and diametral tensile strength, but slightly more corrosion weight loss in 0.05% HC1, 1% Lactic acid solution than that in amalgam. And gallium. alloy showed the same corrosion weight loss in 1% NaCl and Artificial saliva as in amalgam.2. Biological evaluation of Gallium. alloy(1) The Mutagencity to gallium alloy as compared with that of amalgam as a control. In comparison to both group, no significant difference were observed in Rec and Ames test. (2) The tissue culture test: In comparison to gallium, alloy, Amalgam, Pure Nickel, no significant difference were observation in cell culture test.(3) The pulpal response to galliuri alloy as compared with that of amalgam as a control in 132 primary teeth. In comparison to both groups, no significant differences were observed in pulpal response. (4) The primary irritation to the human skin of gallium alloy was not observed.3. Clinical observation Thirty-two Class I cavities in primary teeth filled by gallium alloy were clinical observed for 3 months. The slight surface roughness was noted in case 13 and step case in 4, but falling off and cracks were not found after 3 months. By repolishing in the case with discoloration, surface roughness and step at the patients second visit, it appeared that there were no problem in the clinical use of gallium alloys.