EVALUATION OF MERCURY RELEASE FROM DENTAL AMALGAMS

尽管公众意识和专业人士对 汞在牙科汞合金中的使用，只有少数研究小组致力于 为确定最终暴露量和生物 这个元素的影响。 因此，许多重要和迫切的 问题仍然没有答案。 这个问题的重要性在于 事实上，大约80%的后牙弓是由 这种材料。 最初研究计划的目标是 系统研究汞的数量、速率和机制 通过溶解从牙科汞合金及其组成相释放 和蒸发。 本提案的总体目标是继续 这一努力，以建立最高价值的水平， 牙科病人及工作人员接触牙科用汞的情况 汞合金 此外，还提供了关于大鼠、机制和 将获得汞合金释放的汞的化学形态。 金膜汞分析仪（杰罗姆411）将用于定量 从液态汞、汞合金和汞合金相中蒸发汞 通过水溶液，如预期在体内发生的。 的影响 腐蚀和疲劳载荷对汞合金汞蒸气释放的影响 也将被研究。 此外，汞蒸气的总量 在研磨、放置、抛光和去除汞合金过程中产生的 将在封闭系统中用蒸汽分析仪定量， 以确定患者和牙科人员的最终暴露量。 原子吸收光谱法将用于定量溶解度 汞在水、盐水和人工 口水 此外，该技术将用于确定 汞以及银、铜、锡和锌的总量， 从汞合金中溶解出来， 解决方案，如在体内遇到的。 最后， 汞合金表面成膜的形成和组成， 空气和盐水中的相将通过X射线光电子 光谱学，因为这种膜已被证明可以阻止汞排放。 相信本研究将更全面地评价 释放机制，以及量化汞的总量 牙科患者和工作人员可能会在日常生活中接触到的 基础

Despite the increased public awareness and professional concern over the use of mercury in dental amalgam, only a few research groups have devoted considerable effort to determining the ultimate exposure and biological effects of this element. Therefore, many significant and imperative questions remain unanswered. The importance of this issue lies in the fact that approximately 80% of all posterior restorations are made from this material. The goal of the original research proposal was to systematically investigate the quantity, rate and mechanisms of mercury release from dental amalgams and their constituent phases by dissolution and evaporation. The overall goal of the present proposal is to continue this effort in order to establish maximum values for the level of exposure for dental patients and personnel to mercury from dental amalgams. In addition, further information on the rat, mechanism and chemical form of mercury released from amalgam will be obtained. A gold film mercury analyzer (Jerome 411) will be used to quantitate the vaporization of mercury from liquid mercury, amalgams and amalgam phases through aqueous solutions, as is expected to occur in vivo. The effects of corrosion and fatigue loading on mercury vapor release from amalgam will also be studied. In addition, the total amount of mercury vapor generated during trituration, placement, polishing and removal of amalgam will be quantitated in a closed system with the vapor analyzer, in order to determine the ultimate exposure to both patient and dental personnel. Atomic absorption spectroscopy will be used to quantitate the solubility limits and dissolution rate of mercury in water, saline and an artificial saliva. In addition, this technique will be employed to determine the total amount of mercury, as well as silver, copper, tin and zinc, dissolving from amalgam immersed in a flowing, continuously replenished solution, as would be encountered in vivo. Finally, the rate of formation and composition of the surface film forming on amalgam and its phases in air and saline will be determined by x-ray photoelectron spectroscopy, since this film has been shown to retard mercury emission. It is believed that the present study will more completely evaluate the mechanisms of release, as well as quantitate the total amount of mercury that the dental patient and personnel may be exposed to on a routine basis.