Silver Fillings, Amalgam, is one of the most commonly used materials to fill cavities in back teeth. It contains a mixture of silver, tin, copper, zinc, and mercury, which bond to create an alloy. The mercury found in amalgams is not in the harmful “free” form. Because of this, the mercury in amalgams is stable and safe for use according to the American Dental Association (ADA) and the U.S. Public Health Service. According to some studies, exposure to mercury in drinking water and food is greater than that to all the mercury in a mouthful of fillings. Amalgam fillings are strong and have been successfully used in people’s mouths for the last 150 years.
However, there are many other studies that claim the mercury in dental amalgam is very toxic and dangerous, and can lead to arthritis, Alzheimer’s disease, and many other neurological disorders. In fact, in Germany, there is a partial ban on the use of amalgam, and a total ban in Sweden. Although the evidence of mercury leakage to date has not passed scientific absolution, there is however a myriad of enough good solid reasons to discontinue its use as much as possible. Amalgams leak, expand, and since they are not bonded into the tooth, they act as a wedge and wedge the tooth into a fracture. Since amalgam restorations are maintained in the tooth via mechanical retention that the dentist cuts into the tooth, the preparation process required in using amalgam results in more extensive destruction of healthy tooth structure. Amalgam is also an unattractive restoration to be placed on white/ivory colored teeth. It starts out silver in color and over time turns black. Not only does it cause the tooth to appear gray and eventually black from the front, it also stains the tooth from within making it nearly impossible for it to have a natural appearance.
That being said, there are some instances where amalgam is the best choice for restoring a tooth for a particular individual. It can be placed more predictably in areas that are hard or impossible to isolate from saliva than can bonded materials such as tooth colored fillings. It also is usually less expensive and less time consuming to place.