A crown is a restoration that covers, or "caps," a tooth to restore it to its normal size and shape, strengthening and improving the appearance of a tooth. Crowns are necessary when a tooth is generally broken down and a filling will not solve the problem. If a tooth is cracked, a crown holds the tooth together to keep the damage from getting worse. Crowns are also used to restore a tooth when there isn't enough of the tooth remaining to provide support for a large filling, when a tooth is broken or severely discolored, and to protect a tooth after a root canal procedure is completed.
A bridge (or fixed partial denture) is a fixed replacement for a missing tooth. The teeth on either side of the missing tooth are used as anchors and the replacement tooth is fused between crowns that are cemented onto the anchor teeth.
Both crowns and bridges are fabricated out of all-ceramic, metal and ceramic, and all-metal restorative materials.