Resins and Amalgam

Amalgam
  • Made of: A mixture of silver, tin, zinc, copper and mercury. Mercury is nearly 50% of the mixture.
  • Types: Traditional (non-bonded)
  • Used for: Fillings in back teeth
  • Lasts: At least 10 years, usually longer
  • Costs: The least expensive type of restorative material
Advantages
  • Amalgam fillings are strong. They can withstand the forces of chewing.
  • They are less costly than the alternatives.
  • Amalgam fillings can be completed in one dental visit.
  • They are less sensitive to moisture during the filling process than composite resin.
Composite Resin
  • Made of: A mixture of plastic and fine glass particles.
  • Types: Direct and indirect. Direct fillings are placed by your dentist using a bright blue light that hardens the soft material. For indirect fillings, your dentist prepares the tooth and takes an impression of it. A laboratory or the dentist then will make the filling from the mold. During a second visit, your dentist cements this filling into place.
  • Used for: Small and large fillings, especially in front teeth or the visible parts of teeth; also for inlays
  • Lasts: At least five years
  • Costs: More than amalgam, but less than gold
Advantages
  • Your fillings or inlay will match the color of your teeth.
  • A filling can be completed in one dental visit. An inlay may require two visits.
  • Composite fillings can bond directly to the tooth. This makes the tooth stronger than it would be with an amalgam filling.
  • Less drilling is involved than with amalgam fillings. That’s because your dentist does not have to shape the space as much to hold the filling securely. The bonding process holds the composite resin in the tooth.
  • Indirect composite fillings and inlays are heat-cured. This step increases their strength.
  • Composite resin can be used in combination with other materials, such as glass ionomer, to provide the benefits of both materials.