How long will a crown last?

A well designed crown placed on a tooth that can be kept clean and has no unusual circumstances will last on average around 10 years. I have seen crowns 30+ years old and I have seen some that failed within the first year. The major factors are biting forces which are applied, home care by the patient, and choice of appropriate material for the crown. Most people want the tooth colored porcelain type crowns, but sometimes, a full metal or metal base crown is the better selection due to the circumstances. This is determined on a case by case basis with the help of your Dentist.


What are dental crowns?

Crowns, or Caps as known by some, are dental restorations that provide for repair of the complete tooth. They sit on top of the tooth and completely surround the remaining tooth structure which supports it from under the crown. A crown will be recommended when a tooth that need to be restored has around 50% or less natural tooth remaining, is a back tooth and has been treated with root canal therapy, or some special circumstances where a normal filling would not be considered strong enough. Crowns are made of metal, porcelain or a combination depending on the tooth and function that is needed.


When is a crown necessary?

A crown is needed when there is a loss of around 50% or more of natural tooth structure. Crowns are designed to spread the chewing forces around the tooth and onto the roots, much like support beams in a building. When a tooth has around 50% or less remianing structure or has root canal therapy, the tooth is at a higher risk for fracture. By placing a crown, the natural tooth remains, which the body likes, and the functional forces that are placed on the tooth are spread out and reduces the chance for a fracture. A crown may also be recommended when certain conditions exist that would place unusual heavy forces on a tooth that could otherwise get a regular filling. It is determined on a case by case basis.