A dental crown is a tooth-shaped "cap" that is placed over a tooth (cover the tooth) to restore its shape, size, strength, and improve its appearance. The crown, when cemented into place, fully encases the entire visible portion of a tooth that lies at and above the gum line.

 

Why Is a Dental Crown Needed?

A dental crown may be needed in the following situations:

• To protect a weak tooth (for instance, from decay) from breaking or to hold together parts of a cracked tooth.

• To restore an already broken tooth or a tooth that has been severely worn down.

• To cover and support a tooth with a large filling when there isn't a lot of the tooth left.

• To hold a dental bridge in place.

• To cover misshapen or severely discolored teeth.

• To cover a dental implant.

• To make a cosmetic modification.

 

For children, a crown may be used on primary (baby) teeth in order to:

• Save a tooth that has been so damaged by decay that it can't support a filling.

• Protect the teeth of a child at high risk for tooth decay, especially when a child has difficulty keeping up with daily oral hygiene.

 

In such cases, a pediatric dentist is likely to recommend a stainless-steel crown.

 

What Types of Crowns Are Available?

Permanent crowns can be made from stainless steel, all-metal (such as gold or another alloy), porcelain-fused-to-metal, all resin, or all ceramic.

• Stainless steel crowns are prefabricated crowns that are used on permanent teeth primarily as a temporary measure. The crown protects the tooth or filling while a permanent crown is made from another material. For children, a stainless-steel crown is commonly used to fit over a primary tooth that's been prepared to fit it. The crown covers the entire tooth and protects it from further decay. When the primary tooth comes out to make room for the permanent tooth, the crown comes out naturally with it. In general, stainless steel crowns are used for children's teeth because they don't require multiple dental visits to put in place and so are more cost-effective than custom-made crowns and ongoing dental care needed to protect a tooth without a crown.

• Metals used in crowns include alloys that have a high content of gold or platinum, or base-metal alloys (for example, cobalt-chromium and nickel-chromium alloys). Metal crowns withstand biting and chewing forces well and probably last the longest in terms of wear down. Also, metal crowns rarely chip or break. The metallic color is the main drawback. Metal crowns are a good choice for out-of-sight molars.

• Porcelain-fused-to-metal dental crowns can be color-matched to your adjacent teeth (unlike the metallic crowns). However, sometimes the metal underlying the crown's porcelain can show through as a dark line, especially at the gum line and even more so if your gums recede. These crowns can be a good choice for front or back teeth as well as long bridges where the metal is needed for strength.

• All-resin dental crowns are less expensive than other crown types. However, they wear down over time and are more prone to fractures than porcelain-fused-to-metal crowns. 

• All-ceramic or all-porcelain dental crowns provide better natural color match than any other crown type and may be more suitable for people with metal allergies. All-ceramic crowns can be used for front and back teeth.

 

 

What is the Dental Crown Procedure?

The dental crown process requires two visits. During the first visit, the tooth is prepared by filing or reshaping to allow room for the crown to be placed. This process depends on the type of crown being used. Metal-based crowns are generally thinner than porcelain crowns and, therefore, don’t require the removal of as much of the tooth structure. If the tooth structure is severely decayed or damaged a filling material may be needed to build up the structure of the tooth to allow a crown to be placed. After the tooth has been properly shaped an impression is made of the tooth using a paste or putty. The impression is sent to a laboratory to construct the crown, which takes approximately two to three weeks to complete. A temporary crown will be placed over the tooth to protect it until your custom crown has been constructed and is ready to be fixed in place.

 

At your second visit, the temporary crown is removed, and the permanent custom-made crown is set in place. The fit and the color of the crown will be checked to ensure it matches your natural surrounding teeth.  Dental cement is used to fix the crown in place. Your bite will then be checked and small adjustments will be made if necessary.