A damaged tooth can be restored with a crown. A crown is indicated following a root canal or other trauma, and this is done to strengthen and improve the appearance of the tooth. The dental technician produces the crown according to the impression taken by the dentist. Several types of crowns available, and the most esthetic crows are zirconium and ceramic crowns . A bridge is a fixed dental restoration ( fixed denture ) used to replace one or more missing teeth permanently to adjacent teeth .