Crowns

Crowns are made of different materials and in a number of different ways. But before we talk about what crowns are made of, we need to know what a crown is.

Crowns are commonly used when repairing a tooth. And while there are many reasons for placing a crown, the following are the most common. A tooth with a worn out large old filling can be safely fixed with a crown. A broken down tooth, or a tooth with a Root Canal Treatment or a tooth with multiple fracture lines are all good reasons for having a crown placed. Esthetics is yet another reason why a crown can be placed.

A crown can be made from combination of different materials or different forms of the same material. For example, a gold crown not only has gold in it, but it also has other metals such as platinum and palladium as well. Gold, platinum, palladium and all the other minute elements in this category are essentially all metals. On the other hand, a more common scenario is the use of a Porcelain Fused to Metal (or PFM for short) crown. In this case, porcelain is chemically and mechanically fused to the metallic part of the crown.

The most esthetic crowns are those that are made strictly out of a resin reinforced material or combination of porcelain and ceramic layers.

All Porcelain crowns (outside) All Porcelain crowns from the inside

However, there are times that using this type of crown are not recommended. For instance, placing a crown made of this fashion on a back tooth on a person with heavy chewing forces can cause the crown to break prematurely. Therefore, it is essential to weigh all the risks and benefits in trying to decide what type of crown to use.

A Porcelain Fused to Metal (PFM) crown can esthetically look very pleasing if done correctly.

A PFM crown as seend from the outside The inside metallic part of a PFM crown

The metal portion is in immediate contact with the tooth (forming a very thin shell for the tooth) while Porcelain is baked onto the metal and masking its presence. PFM crowns can be used in the back parts of the mouth as well as the front parts. However, in the front of the mouth, a PFM crown can cause lighting issues which makes the gums around the neck of the tooth look dark.

Gold crowns have been around for a long time. They have been declining in popularity though due to obvious esthetic reason for some time now.

A gold crown on a back bottom tooth Their use is practically limited to teeth in the back of the mouth (unless you are a boxer who enjoys bearing your "gold tooth" to your opponent).