Dental Crown is a restoration that reproduces the entire surface anatomy of the clinical crown of a tooth. It may be a metal casting, a porcelain fused to metal casting, a metal casting with a veneer of acrylic resin or a jacket crown constructed of porcelain or acrylic resin. Its abutment can be a prepared tooth or an implant abutment. The prepared tooth abutment may be sound, or it may be partially rebuilt by a cast metal core or a cast core and post, cemented to the remaining tooth structure, or by composite resin or by amalgam. Occasionally small areas of the tooth stump may be restored with composite resin.
Crown prosthodontics is the science and art of the complete restoration of a single tooth.
Dental crowns may be divided into three main groups:
1. those which partially cover the natural crown of the tooth.
2. those which completely cover the crown.
3. those which replace the natural crown entirely and are retained by means of a post cemented into a root canal.
Crowns may also be divided according into what they restore:
1. crowns for natural tooth.
2. implant crowns.
Crowns may also be classified according to its location.
1. dental crowns on anterior teeth.
2. dental crowns on posterior teeth.
Implant crowns can be:
1. screw retained crown.
2. cement retained crown.
The Need for Dental Crowns
Before crowning a tooth, one of the following conditions must be met:
1. The tooth should have extensive restorations and be required as an abutment for an RPD.
2. It should be a heavily restored tooth and should oppose a natural tooth with no other vertical stops on the side of the arch.
3. Crowning is the only way to improve esthetics.
4. Crowning is required to correct the integrity of the occlusal plane.
5. An endodontically treated multirooted tooth is under extensive load from a natural dentition.
Pictures of Dental Crowns
Porcelain Fused to Metal Dental Crown
References
Johnston J F et al: Modern practice in crown and bridge prosthodontics. WB Saunders Company
Owall B et al: Prosthodontics principles and management strategies. Mosby-Wolfe 1996