In dentistry, a crown most commonly refers to a dental cap, a type of dental restoration that completely caps or encircles a tooth or dental implant. A crown may be needed when a large cavity threatens the health of a tooth. A crown is typically bonded to the tooth by dental cement. They can be made from various materials, which are usually fabricated using indirect methods. Crowns are used to improve the strength or appearance of teeth and to halt deterioration. While beneficial to dental health, the procedure and materials can be costly.
The most common method of crowning a tooth involves taking a dental impression of a tooth prepared by a dentist, then fabricating the crown outside of the mouth. The crown can then be inserted at a subsequent dental appointment. This indirect method of tooth restoration allows use of strong restorative material requiring time-consuming fabrication under intense heat, such as casting metal or firing porcelain, that would not be possible inside the mouth. Because of its compatible thermal expansion, relatively similar cost, and cosmetic benefit, some patients choose to have their crown fabricated with gold.
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