Onlays are used for restorative or cosmetic work on the top of a tooth including the cusps (bumps on top of the tooth). They are made of natural looking, non-metallic composites or porcelain material. They can be used in cases of cavities, replacement of a crown or filling, as well as other situations.
Onlays extend over one or more sides of a tooth, and are used much as a crown or cap are. However, the amount of existing tooth that has to be removed is minimal, repairing only the damaged part of the tooth.
As with other procedures, an impression of the tooth is taken and used to create a custom piece. A temporary onlay is used until the permanent onlay is ready, installed and permanently bonded to the tooth.