Amalgam Dental Fillings as the Source of Mercury Exposure and Alternative Solutions

Abstract

The amalgam filling plays a major role in restorative dentistry when applied and has additional strength due to its contents, such as mercury and other alloys that could be Cooper, Silver, Tin, or Zinc. A concern has been raised that amalgam causes mercury toxicity and two primary organs are the kidney and the central nervous system that are affected by Hg poisoning.The objective of the present study is to examine new dental amalgam fillings and old amalgam fillings removed from patııent's teeth in term of a potential cause of mercury exposure, in addition to the alternative dental fillings. The technique of this study is a metallographic evaluation by using the rapid analytical technique of X-ray diffraction (XRD). Moreover, the specimens used have been obtained from a different set of amalgam fillings, to measure the mercury present in an unmixed sample, a mixed sample according to the manufacturer's recommendations, and dental amalgam fillings that had been in the patient's theeth after filling them for 15 and 20 years to analyze exposure to mercury by comparison. Mercury unmixed sample contains on silver Tin 64% and Copper Zinc 36% While mixed samples contain of Silver Mercury 63% and Copper Tin 37%, the sample after 15 years’ dental amalgam filling induced when the Silver mercury contain is increased to 84% and low Copper Tin 16%, While the sample after 20 years’ dental amalgam filling containing approximately Silver Mercury contain is 80% and Copper Tin 20%.

Keywords

• Amalgam
• Mercury exposure
• XRD
• Alloys

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