A crown is a type of dental restoration which completely caps or encircles a tooth or dental implant. Crowns are often needed when a large cavity threatens the ongoing health of a tooth. They are typically bonded to the tooth using a dental cement. Crowns can be made from many materials. Crowns are often used to improve the strength or appearance of teeth.
A bridge is a fixed dental restoration used to replace a missing tooth by joining an artificial tooth permanently to adjacent teeth or dental implants. Types of bridges may vary, depending upon how they are fabricated and the way they anchor to the adjacent teeth.