Today there are more choices for restorative materials than at any time in the past. Dental amalgam, also known as silver fillings, is one choice for teeth in the back of the mouth that has been in use for around 150 years. Amalgam is a metal alloy that contains silver, tin, copper, and mercury. Amalgam lasts a long time and is less expensive than other materials such as tooth-colored composites, porcelain, or gold.
Silver fillings have been used successfully for around 150 years, but you may wonder about the mercury content in this filling material. When mercury combines with the other metals it forms a stable and safe “amalgam” material. There is more than one form of mercury. There is methylmercury, elemental mercury, and inorganic mercury. Methylmercury, or organic mercury, is the form of mercury that can accumulate in water sources and be absorbed by the fish we eat. If you ever eat canned tuna, you have been exposed to methylmercury. Methylmercury has been linked to various systemic effects. Dental amalgam does not contain methylmercury, but rather elemental mercury. Methylmercury is absorbed through the digestive tract while elemental mercury is absorbed through the lungs from vapor created while chewing. This vapor, while it does exist, is measured in parts per billion, so exposure is very small.