A woman is smiling at her dentist

What to Know About Amalgam Fillings

Dental amalgam is a material used to fill cavities. It’s a mixture of liquid mercury and a powdered alloy composed of silver, tin, and copper.The chemical properties of the mercury allow it to react, with and bind together the silver/copper/tin to form an amalgam.

Also known as “silver fillings”, dental amalgam has been used for more than 150 years in hundreds of millions of patients around the world. It’s popular because it lasts a long time and is less expensive than other cavity-filling materials. Because of their durability, amalgam fillings are often the choice for large cavities or those that occur in the back teeth where a lot of force is needed to chew.

One disadvantage of amalgam is that these types of fillings are not natural looking, especially when the filling is near the front of the mouth. Also, to prepare the tooth, your dentist may need to remove more tooth structure to place an amalgam filling than for other types of fillings.

Are Amalgam Fillings Safe?

Because they contain mercury, many people wonder about the safety of amalgam fillings. When combined with the other metals, the mercury forms a safe, stable material. It’s also important to note that there are different kinds of mercury. The type used in dental amalgams is not the same as the mercury [methylmercury] found in water that can build up in fish and lead to health problems.

If your fillings are in good condition and there is no decay beneath the filling, the FDA does not recommend that you have your amalgams removed or replaced.

Preventing the Need for Dental Fillings

Ultimately, the best dental filling is no dental filling. You can decrease the risk of cavities by: