Evaluation of the embryotoxicity of dental alloys containing indium

对含铟牙科合金、添加比例为10%、15%和20%的铟合金;添加比例为2%、4%和6%的银、钯、金、铜和铟合金;以及用于瓷粘结的金合金进行了检查，以通过在Dulbecco改良Eagle培养基（DMEM）中用金刚石粉末加速浸提来评价胚胎毒性风险。使用小鼠源性ES-D3细胞对每种浸提液的胚胎毒性水平进行检查，证明仅银-20%铟合金可能具有胚胎毒性。人工唾液中的ES-D3细胞未分化，提示咬合磨损导致合金成分洗脱。因此，我们使用以下程序模拟了银-20%铟合金、银、钯、金、铜和6%铟的合金的口洗脱的实际条件。首先，将左右磨牙的锚牙固定在上下颌模型中，并使用上述合金制作全铸造冠。最后，抛光牙冠表面，并重复移动模型的上颌6或12小时，以便对牙冠表面施加重复的磨损运动。用ICPS测量，测得从合金中洗脱的铟、银、钯或铜离子的量小于1 ppm。此外，银、钯、金、铜、铟合金的胚胎毒性均弱于银铟合金，为验证Ag-20%合金的胚胎毒性，采用大鼠全胚胎培养法进行了发育毒性试验。试验结果表明，卵黄囊直径、顶臀长、头长、体节数和蛋白质含量与对照组相比差异不显著。因此，胚胎未发现异常，结果表明，本试验所检测的含铟合金的胚胎毒性风险很低。

Dental alloys containing indium, indium alloys with additive ratios of 10%, 15% and 20% ; alloys of silver, palladium, gold, copper and indium with additive ratios of 2%, 4% and 6% ; and a gold alloy for porcelain bonding were examined to evaluate the embryotoxicity risk by accelerated extraction with diamond powder in Dulbecco's Modified Eagle Medium (DMEM). An examination of the embryotoxicity level of each extract using mouse-derived ES-D3 cells demonstrated the possibility of embryotoxicity only for silver-20%indium alloys. The ES-D3 cells in artificial saliva did not differentiate.This suggests elution of the alloy content due to occlusal wear. Accordingly, we simulated the actual conditions of mouth elution of the silver-20% indium alloy, the alloys of silver, palladium, gold, copper and 6%indium using the following procedure. First, anchor teeth for the left and right molars were fixed in a maxillomandibular model, and full cast crowns were made using the above alloys. Finally, the crown surface was polished, and the upper jaw of the model was repeatedly moved for 6 or 12 hours, in order to apply repetitive wear motions to the crown surface. Measurements with ICPS measured the amounts of indium, silver, palladium or copper ions eluted from the alloys to be less than 1 ppm. Furthermore, it was suggested that the embryotoxicity of the alloys of silver, palladium, gold, copper and indium were weaker than those of silver-indium alloys.To examine the supposed embryotoxicity risk of the alloy of Ag-20%, a developmental toxicity test was conducted by the rat whole-embryo culture method. The test results showed that there was no significant difference in yolk-sac diameter, crown-rump length, head length, number of somites and protein content compared to those in the control group. Therefore, no abnormalities were found in the embryos.The results demonstrate that the embryotoxicity risk of alloys containing indium examined in this test is very low.