The facts on fillings: Amalgam vs. resin composite

You and your dentist have two choices when it comes to fillings: amalgam (a mixture of metals) and resin composite (ceramic and plastic compound). Each type of filling has advantages and drawbacks. Let’s take a closer look.

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, binds the metals together to provide a strong, durable filling. When combined with the other metals, the mercury in fillings forms a safe, stable compound. This type of filling has been around since 1895.

What are the pros and cons of amalgam fillings?

Advantages	Drawbacks
Proven. Amalgam fillings have been used for over a century. Economical. Amalgam generally costs less than resin composite. Long-lasting. These fillings usually lasts 10 to 15 years, so you don’t have to go under the drill as often.	Noticeable. Unlike tooth-colored resin, metal fillings are hard to miss when you open wide. Allergies. Some people are sensitive to the metals in amalgam.

What are resin composite fillings?

Resin composite fillings are made of a ceramic and plastic compound. Because resin mimics the appearance of natural teeth, these fillings blend right in. They’re also known as “white fillings” or “tooth-colored fillings.”

What are the pros and cons of resin composite fillings?

Advantages	Drawbacks
Invisible. The same color as your teeth, these fillings blend in. Easy adhesion. Resin composite bonds to the surface of your tooth. Preserves maximum amount of tooth. The flexibility of resin composite means less drilling is required.	More frequent replacement. Resin composite fillings last five to seven years, which is half the lifetime of an amalgam filling. Takes longer. The process of placing a resin filling is more involved, so it takes more of your time and the dentist’s.

Are both types of fillings covered by my dental plan?

It depends on your plan. Many dental plans do not cover resin composite fillings on back teeth (molars). Amalgam fillings are more durable, especially for chewing surfaces. But if you or your dentist prefers composite fillings, your plan will cover its share up to the cost of an amalgam filling, and you are responsible for the difference.

For specific details about your coverage, check your plan booklet.

Which type of filling should I 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. If you have any questions about fillings, ask your dentist.

Related reading

• Fillings: A guide to cavity treatment
• Cavities: Not just for kids
• Managing your anxiety about going to the dentist

The oral health information on this website is intended for educational purposes only. You should always consult a licensed dentist or other qualified health care professional for any questions concerning your oral health.