Dental Crowns

Long term cosmetic restorations which hold the tooth together, how many times has your filling chipped off?

The part of a natural tooth above the gum line, covered with enamel, is called the ‘crown’ of the tooth. Simply, it is the tooth visible to us in general. Sometimes the enamel becomes discoloured, decayed, or misshapen. It is removed by dental work and replaced with a new covering, called crown. In cosmetic dentistry, a crown is a type of dental restoration that fully covers part of the natural tooth lying above the gum line. 

Composition of Dental Crowns

A dental crowns used as restorative is usually made of porcelain, metal like gold etc., metal alloy, or a combination of these. To give extra strength to the crown, it is made of porcelain covering an internal metal coping. Following three types of crowns are used in common dental practice:

• Gold Crowns
• Porcelain Crowns
• Porcelain Fused-to-Metal Crowns

Gold Crowns

Gold crowns are relatively easy to prepare and do not cause wear on opposing teeth. They also provide a healthier environment for the gum tissue. The main disadvantage of gold crowns is their colour that does not match that of natural teeth and hence is not preferred for front teeth restoration.

Porcelain Crowns

The main reason of preferring a porcelain crown is that it looks as natural as one's own natural tooth. Two main disadvantages are encountered in fitting a porcelain crown for restoration:

• It requires removal of more tooth structure for a proper fit.
• Patients choosing it for restoration commonly report gum inflammation.

Porcelain Fused-to-Metal Crowns

These crowns too have a very natural look. However, they fail to replicate the translucency of natural tooth because of having a metal substructure. Sometimes, a dark line is visible at the edge of the crown, near the gum line.

Other Types of Crowns

Besides the three main types, other types of crowns are also used in dental restoration. These include:

• Polycarbonate Crowns: used for restoring front teeth
• Stainless steel Crowns: used for restoring back teeth

Teeth that Need Crowns

This type of teeth needs restoration with crowns:

• Back teeth having a history of root canals
• Teeth consisting of more than half filling material
• Teeth that have circumferential gingival decay i.e. the decay is spreading at the gum line
• Teeth that appear ugly due to wear, discoloration etc.