Indications for dental crowns
- Replace failed existing crowns
- Restore badly broken down, worn, or fractured teeth
- Improve aesthetics of unsightly teeth
- Maintain structural stability of extensively restored teeth
- Restore the visible portion of a dental implant
Restoration of endodontically treated teeth
- No strong evidence to show that crowns are better than other restorations for root-filled teeth
- Dentists should use clinical experience and patient preferences to decide on crown use
- Crowns justified when access cavity exceeds one third of occlusal surface or when walls and marginal ridges are missing
3/4 and 7/8 crowns
- Hybrid between onlay and full crown
- Covers three out of four walls of the tooth
- Often fabricated in gold
- Grooves or boxes added for increased retention
- Technically difficult and poor patient acceptability due to metal showing through
Full metal crowns
- Cast entirely in a metal alloy
- Alloys categorised as high-noble, noble, or base metal
- Gold alloys commonly used for casting crowns
- Palladium-based alloys introduced as a cheaper alternative to gold
- Base-metal alloys also used
Types of gold alloys
- Gold alloys used in casting crowns contain metals like copper, platinum, palladium, zinc, indium, and nickel
- Type III and IV alloys commonly used for full crowns
- Gold crowns indicated for posterior teeth due to aesthetic reasons
- Durable and require minimal tooth preparation
- Have good dimensional accuracy and similar wear properties to enamel
In dentistry, a crown or a dental cap is a type of dental restoration that completely caps or encircles a tooth or dental implant. A crown may be needed when a large dental cavity threatens the health of a tooth. Some dentist will also finish root canal treatment by covering the exposed tooth with a crown. A crown is typically bonded to the tooth by dental cement. They can be made from various materials, which are usually fabricated using indirect methods. Crowns are used to improve the strength or appearance of teeth and to halt deterioration. While beneficial to dental health, the procedure and materials can be costly.
| Crown (dental restoration) | |
|---|---|
 An anterior dental crown on post | |
| ICD-10-PCS | Z98.811 |
| ICD-9-CM | 23.41 |
| MeSH | D003442 |
The most common method of crowning a tooth involves taking a dental impression of a tooth prepared by a dentist, then fabricating the crown outside of the mouth. The crown can then be inserted at a subsequent dental appointment. This indirect method of tooth restoration allows use of strong restorative material requiring time-consuming fabrication under intense heat, such as casting metal or firing porcelain, that would not be possible inside the mouth. Because of its compatible thermal expansion, relatively similar cost, and cosmetic difference, some patients choose to have their crown fabricated with gold.
Computer technology is increasingly employed for crown fabrication in CAD/CAM dentistry.
