Dental Amalgam is a commonly used dental filling that has been around for 150 years. It is a mixture made up of mercury and at least one other metal.
Amalgam has many advantages over other restorative materials; it is low cost, strong, durable, and has bacteriostatic effects.
Amalgam is used in a variety of dentistry procedures. One reason it is used so often is because it is relatively easy to use during placement. It also remains soft for a short time and can be packed to fill any irregular volume before it forms a hard compound. In addition, Amalgam has the greatest longevity over other direct restorative materials, such as composite. On average, most amalgam restorations can last for 10 to 12 years. On the other hand, resin-based composites serve for about half that time. It is important to note, however, that with recent improvements in composite material science and a better understanding of the technique-sensitivity of placement, this difference is decreasing.
There are certain circumstances in which composite, or white fillings, serve better than amalgam. When amalgam is not indicated, or when a more conservative preparation would be beneficial, composite is the chosen restorative material. For example, when a small occlusal restoration is needed, the amalgam would require the removal of a more sound tooth structure, as well as in “enamel sites beyond the height of contour.”
Both amalgam and composite materials are considered safe and effective for tooth restoration as concluded by The American Dental Association Council on Scientific Affairs.