Mercury makes up about 40-50 percent of the compound. Mercury is used to bind the metals together and to provide a strong, hard durable filling. After years of research, mercury has been found to be the only element that will bind these metals together in such a way that can be easily manipulated into a tooth cavity. How mercury effects the body is in large part determined by what type of mercury is present. Amalgam is a very durable material and has been used for more than 150 years.
Dentists appreciate using dental amalgam because it is easier to work with than other alternatives.
Dentists also believe that patients prefer dental amalgam to other alternatives because of its safety, cost-effectiveness, and ability to be placed in the tooth cavity quickly. Alternatives to amalgam, such as cast gold restorations, porcelain, and composite resins are more costly. However, composite compounds are constantly improving. The incidence of allergy to mercury is far less than one percent of the population. People suspected of having an allergy to mercury should receive tests by qualified physicians, and, when necessary, seek appropriate alternatives.