汞从牙科汞合金释放到持续补充的液体中。

Mercury release from dental amalgams into continuously replenished liquids.

作者信息

Okabe T, Elvebak B, Carrasco L, Ferracane J L, Keanini R G, Nakajima H

机构信息

Department of Biomaterials Science, Baylor College of Dentistry, Texas A&M University Health Science Center, 3302 Gaston Avenue, Dallas, TX 75246, USA.

出版信息

Dent Mater. 2003 Jan;19(1):38-45. doi: 10.1016/s0109-5641(02)00010-6.

DOI:10.1016/s0109-5641(02)00010-6

PMID:12498895

Abstract

OBJECTIVE

Studies have been performed using high- and low-copper amalgams to measure the amounts of mercury dissolution from dental amalgam in liquids such as artificial saliva; however, in most cases, mercury dissolution has been measured under static conditions and as such, may be self-limiting. This study measured the mercury release from low- and high-copper amalgams into flowing aqueous solutions to determine whether the total amounts of dissolution vary under these conditions when tested at neutral and acidic pH.

METHODS

High- and low-copper amalgam specimens were prepared and kept for 3 days. They were then longitudinally suspended in dissolution cells with an outlet at the bottom. Deionized water or acidic solution (pH1) was pumped through the cell. Test solutions were collected at several time periods up to 6 days or 1 month and then analyzed with a cold vapor atomic absorption spectrophotometer. After dissolution testing, the specimens were examined using SEM/XEDA for any selective degradation of the phases in the amalgam.

RESULTS

Except for the high-copper amalgam in the pH1 solution, the dissolution rates were found to decrease exponentially with time. The rate for the high-copper amalgam in pH1 solution slowly increased for 1 month. The total amounts (microgram/cm(2)) of mercury released over 6 days or 1 month from both types of amalgam in deionized water were not significantly different (p>/=0.05). The high-copper amalgam released significantly more mercury than the low-copper amalgam in the pH1 solution at both time periods. For both amalgams, the dissolution in pH1 was significantly higher than in deionized water.

SIGNIFICANCE

Mercury dissolution from amalgam under dynamic conditions is enhanced in an acidic media, and most prominently for a high-copper formulation.

摘要

目的

已开展研究，使用高铜和低铜汞合金来测量牙科汞合金在人工唾液等液体中的汞溶出量；然而，在大多数情况下，汞溶出量是在静态条件下测量的，因此可能会自我限制。本研究测量了低铜和高铜汞合金在流动水溶液中的汞释放量，以确定在中性和酸性pH条件下测试时，这些条件下的总溶出量是否会有所不同。

方法

制备高铜和低铜汞合金标本并保存3天。然后将它们纵向悬挂在底部有出口的溶出池中。将去离子水或酸性溶液（pH1）泵入池中。在长达6天或1个月的几个时间段收集测试溶液，然后用冷蒸气原子吸收分光光度计进行分析。溶出测试后，使用扫描电子显微镜/能量散射X射线能谱仪检查标本中汞合金各相的任何选择性降解情况。

结果

除了pH1溶液中的高铜汞合金外，发现溶出率随时间呈指数下降。pH1溶液中高铜汞合金的溶出率在1个月内缓慢增加。在去离子水中，两种类型的汞合金在6天或1个月内释放的汞总量（微克/平方厘米）没有显著差异（p≥0.05）。在两个时间段内，pH1溶液中高铜汞合金释放的汞明显多于低铜汞合金。对于两种汞合金，pH1条件下的溶出量明显高于去离子水中的溶出量。