Dental Fillings: Composite Resin and Amalgam

Dental fillings are one of the most common types of procedures that dentist perform. No one looks forward to them, but they are very important in preventing further damage to a tooth affected by tooth decay or one that has fractured.

Possible reasons for getting a dental filling:

  • Cavity
  • Fractured tooth
  • Discoloration
  • Gradual loss of tooth structure

Tooth Decay

The most common reason for needing a dental filling is having tooth decay. Tooth decay is caused by the presence of oral bacteria that gradually eat away at the tooth enamel – the white, outer part of the tooth. Although tooth enamel is a very strong material, the acids produced by bacteria can take their toll. Once a hole has moved through the enamel, the softer dentin layer beneath the enamel allows for the rapid progress of tooth decay. The danger is that the decay will reach the soft inner pulp of the tooth, which could cause the loss of the tooth.

So the main purpose of most dental fillings is to remove this tooth decay and fill in the resulting empty area with an appropriate filling material like composite resin or amalgam.

Composite Resin

Composite resin is a material that is colored like a natural tooth. It is used in dental fillings for a more natural appearance.

Composite offers affordability and flexibility, compared to options like gold that are quite expensive. Another positive quality of composite is that it flexes and bends more readily than amalgam, so it is much less likely to break.


  • Matches the color of your natural teeth.
  • Adheres easily. Composite readily bonds to tooth surfaces.
  • Preserves tooth structure. Less drilling is needed with composite.


  • Frequent replacement. The lifespan of composite is half that of amalgam fillings.
  • Longer process. Placing a composite filling is more complicated, requiring more time.

Amalgam Fillings

Popularly known as “silver fillings,” amalgam is a combination of silver, mercury, tin and copper. Mercury binds everything together to create a strong filling material. In combination with other metals, mercury is known for providing a stable and safe compound.


  • Amalgam has been used in fillings for over a century.
  • Costs less than composite.
  • Amalgam typically lasts from 10 to 15 years.


  • Unlike composite, metal in the mouth is hard to miss.
  • Certain individuals are allergic to amalgam metals.

What type of filling is best for me: composite resin or amalgam?

The decision about what type of filling is best for you will be made by you and your dentist. Some factors that will be considered include cavity size and location, your medical and dental history, aesthetic concerns and expense. If you have any questions about dental fillings, contact us today to inquire or to schedule a consultation.