A Crown or a dental cap is a type of dental restoration that completely caps or encircles a teeth or dental implant. A Crown may be needed when a large dental cavity threatens the health of a teeth.  A Crown is typically bonded to the teeth 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 teeth involves taking a dental impression of a teeth prepared by a dentist, then fabricating the Crown outside of the mouth. The Crown can then be inserted at a subsequent dental appointment. Computer technology is increasingly employed for Crown fabrication in CAD/CAM dentistry. A Dental Bridge is a fixed dental restoration (a fixed dental prosthesis) used to replace one or more missing teeth by joining an artificial teeth definitively to adjacent teeth or dental implants.