The part of a natural tooth above the gum line, covered with enamel, is called the ‘crown’ of the tooth. Simply, it is the part of the tooth that is visible when you smile. Sometimes the enamel becomes discoloured, decayed, or misshapen. This can be 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.
A dental crown used as a restorative is usually made of porcelain, metal like gold, metal alloy, or a combination of these. To give extra strength to the crown, it is made of porcelain covering an internal metal coping.
The Following types of crowns are most commonly used:
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 that their colour does not match that of natural teeth and hence is not preferred for front teeth restoration.
The main reason porcelain crowns are preferred is that they look as natural as one's own natural tooth. Two main disadvantages are encountered in fitting a porcelain crown for restoration:
These crowns too have a very natural look. However, they fail to replicate the translucency of natural teeth because of having a metal substructure. Sometimes, a dark line is visible at the edge of the crown, near the gum line.
Besides the three main types, other types of crowns are also used in dental restoration. These include:
This type of teeth needs restoration with crowns: