Tooth Restorations

What are fillings?

Fillings are special materials that your dentist places on your teeth to repair tooth decay (cavities) or defects on the tooth surface. Fillings (also called restorations) restore the tooth to form and function. Advances in dental materials and methods provide new, effective ways to restore teeth.

There are several different types of restorations, including direct and indirect restorations.

Direct restorations

These require a single visit to place a filling directly into a prepared cavity. Materials used for these filings include:

  • Dental amalgam, also known as silver fillings

  • Composite (resin)

  • Resin ionomer fillings

  • Glass ionomer

Amalgam fillings have been used for decades, and have been tested for safety and resistance to wear. Dentists have found amalgams to be safe, reliable, and effective for restorations.

Glass ionomers are tooth-colored materials made from fine glass powders and acrylic acids. These are used in small fillings that do not have to withstand heavy pressure from chewing. Resin ionomers are made from glass with acrylic acids and acrylic resin. Both of these types of glass ionomers chemically bond to the mineral in the tooth.

Composite fillings are the most esthetic of the tooth-colored direct fillings. They are made from acrylic resin filled with tiny glass or quartz particles. They are not quite as strong or wear resistant as amalgam, but they are stronger and more durable than glass ionomers and can be used on biting surfaces. They are bonded to the tooth.

Indirect restorations

These require 2 or more visits and include:

  • Inlays

  • Onlays

  • Porcelain

  • Veneers

  • Crowns

  • Bridges

These are constructed with gold, base metal alloys, ceramics, porcelain fused to metal, or specially formulated  composites. At the first visit, a dentist will prepare the tooth and make an impression of the area that will be restored. At the second visit, the dentist will cement the new restoration into the prepared area. Some offices use newer technology called CAD/CAM (computer-aided design/computer-aided manufacturing) that allows them to produce the indirect restoration in the office and deliver it at the same appointment, saving you a return visit.


For an indirect restoration, a dentist may use an all-porcelain, or ceramic material. This material looks like natural tooth enamel in color and translucency. Another type of indirect restoration may use porcelain that is fused to metal, which provides added strength. Gold alloys are used often for crowns, foundations for porcelain fused to metal crowns, or inlays and onlays. Inlays and onlays can also be made from ceramic or composite resin materials.  Less expensive metal alloys may be used as different options to gold for all-metal and porcelain fused to metal crowns. Indirect composites are similar to those used for fillings and are tooth-colored. But they are not as strong or wear-resistant as ceramic or metal restorations.