A dental crown is a tooth-shaped "cap" that is placed over a tooth -- to cover the tooth to restore its shape and size, strength, and improve its appearance. Crowns, when cemented into place, fully encase the entire visible portion of a tooth that lies at and above the gum line.
Crowns add strength to teeth that have been weakened by large fillings or prior root canal therapy.
A bridge is a fixed dental restoration used to replace a missing tooth (or several teeth) 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.
The materials used for the bridges include gold, porcelain fused to metal, or in the correct situation porcelain alone. The recipient of such a bridge must be careful to clean well under this prosthesis.