Crowns are synthetic caps, usually made of a material like porcelain, placed on the top of a tooth. They are typically used to restore a tooth’s function and appearance following a restorative procedure such as a root canal. When decay in a tooth has become so advanced that large portions of the tooth must be removed, crowns are often used to restore the tooth. Crowns are also used to attach bridges, cover implants, prevent a cracked tooth from becoming worse, or an existing filling is in jeopardy of becoming loose or dislocated. Crowns also serve a cosmetic use, and are applied when a discolored or stained tooth needs to be restored to its natural appearance.
A tooth must usually be reduced in size to accommodate a crown. A cast is made of the existing tooth and an impression is made. The impression is sent to a special lab, which manufactures a custom-designed crown. In some cases, a temporary crown is applied until the permanent crown is ready. Permanent crowns are cemented in place.