Dental Amalgams (Silver Fillings)

Most people recognize dental amalgams as silver fillings. Dental amalgam is a mixture of mercury, and an alloy of silver, tin and copper. Mercury makes up about 45-50 percent of the compound. Mercury helps 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.

Is mercury in dental amalgam safe?

Mercury in dental amalgam is not poisonous. When mercury is mixes with other materials in dental amalgam, its chemical nature changes, so it is essentially harmless. The amount released in the mouth under the pressure of chewing and grinding is extremely small and no cause for alarm. In fact, it is less than what patients are exposed to in food, air, and water.

Ongoing scientific studies conducted over the past 100 years continue to prove that amalgam is not harmful. Claims of diseases due to mercury in amalgam are anecdotal, as are claims of miraculous cures by removing amalgam. There is no scientific proof behind these claims.

Why do dentists use dental amalgams?

Dental amalgam has withstood the test of time, which is why it is the material of choice. It has a 150-year proven track record and is still one of the safest, durable and least expensive materials to a fill a cavity. We estimate that more than 1 billion amalgam restorations (fillings) happen annually. Dentists use dental amalgams because it is easier to work with than other alternatives. Some patients prefer dental amalgam to other alternatives because of its safety, cost-effectiveness, and ability to adhere in the tooth cavity quickly.

Why don’t dentists use alternatives to amalgam?

Alternatives to amalgam, such as cast gold restorations, porcelain, and composite resins are more costly. Gold and porcelain restorations take longer to make and can require two appointments. Composite resins, or white fillings, are esthetically appealing, but require a longer time to place the restoration. It should also be known that these materials, with the exception of gold, are not as durable as amalgam.

What about patients allergic to mercury?

The incidence of allergy to mercury is 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. Should patients have amalgams removed? No. To do so, without need, would result in unnecessary expense, and potential injury to teeth.

Does any staff risk exposure?

Dentists are using pre-mixed capsules, which reduce the chance of mercury spills. And newer, more advanced dental amalgams contain smaller amounts of mercury than ever before.

An interesting factor can be brought into this: Because dental staff are exposed to mercury more often, one would expect dental personnel to have higher rates of neurological diseases, such as multiple sclerosis. They do not.

What are other sources of mercury?

Mercury is currently in our air, food, and water. We occur higher levels of mercury from these sources than from a mouthful of amalgam.

Sources: Much of this information was received from Jack Mitchem, DMD, professor of dental materials at Oregon Health Sciences University Dental School and past chairman of the American Dental Association Council on Dental Materials, Instruments and Equipment. AGD Impact thanks Recall, the Oregon AGD newsletter, which also contributed to portions of this fact sheet.