The facts on fillings: Amalgam vs. resin composite

You and your dentist have several choices when it comes to selecting materials to fill cavities. Among the choices are tooth-colored fillings made of resin-based composite and traditional dental fillings made of metal amalgam. Amalgam is more durable and less expensive than resin; however, resin fillings mimic the appearance of natural teeth, making them much less visible than amalgam fillings.

What are amalgam fillings? Amalgam fillings are often known as silver fillings. Dental amalgam is a mixture of mercury, silver, tin and copper. Mercury, which makes up about 50% of the compound, is necessary to bind the metals together to provide a strong, hard, durable filling. Although dental amalgam is a commonly used dental material, you may wonder about its mercury content. When combined with the other metals, an amalgam filling forms a safe, stable material.

Dental amalgam is easy to work with and more durable than the resin-based composite, and therefore, in some cases, more appropriate for back teeth fillings. A drawback to an amalgam filling is that, unlike a resin filling, the metal is visible when you open wide.

What are resin composite fillings? Resin composite fillings are made of ceramic and plastic compounds. Because resins mimic the appearance of natural teeth, these fillings blend right in.

Resin filling are strong enough to use in back teeth. Resin composite fillings bond well to enamel, which helps preserve the maximum amount of the tooth structure.

Which type of filling to choose You and your dentist can decide which type of filling is best for you, taking into account the size and location of the cavity, your dental history, cosmetic concerns and cost. Ask your dentist to discuss all of the choices available for dental fillings and to help you decide which alternative is right for you.