What are dental crowns?
A crown is a tooth shaped "cap" that is placed over a tooth to cover the tooth in order to restore its shape, size, strength and improve its appearance. They are very common and can last from 5 to 15 years.
If your dentist has told you that you need a crown, here are some reasons why:
1) To protect a tooth that is weak (from decay, perhaps) from breaking or to hold together parts of a cracked tooth.
2) To restore an already broken tooth or a tooth that has been severely worn.
3) To cover and support a tooth that has a large filling where there isn't a lot of tooth left.
4) To hold a dental bridge into place.
5) To cover mishapened or severely discolored teeth.
6) To cover a dental implant.
7) To make a cosmetic modification.
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.
How long should a crown last?
It would be reasonable to expect that a dental crown could last between 5 and 15 years. Most likely, a crown that has only lasted 5 years would be somewhat of a disappointment to your dentist.
Depending on the general wear and tear the crown is exposed to (chewing and biting, trauma, tooth grinding) and how well you keep the tooth free to dental plaque and take care of it, a crown can last somewhat indefinitely.
There can be a variety of reasons why a crown might need to be replaced, including damage/breakage, excessive wear, tooth decay and cosmetic reasons (the color of the dental crown no longer matches its neighboring teeth.)
What is the procedure for having a crown placed?
Preparing a tooth for a crown involves two visits. During the first visit, the doctor will examine and prepare the tooth. He/She may take some x-rays to check the roots of the tooth and determine if there is any decay or risk of infection or injury to the tooth's pulp. If this is the case, a root canal treatment may need to be performed first.
To begin, the dentist will numb the tooth and gum tissue around the tooth. Next, the tooth receiving the crown is filed down along the chewing surface and sides to make room for the crown. If a large area of the tooth is missing (due to decay or damage), your dentist will use filling material called a "build up" on the tooth to support the crown. After reshaping the tooth, your dentist will use a paste or putty to make an impression of the tooth to receive the crown. Impressions of the teeth above and below the tooth to receive the crown will also be made to make sure that the crown will not affect your bite. A temporary crown will be made to cover and protect the prepared tooth while the crown is being made.
The impressions are then sent to a dental lab where the crown will be manufactured. The crown is then returned to the dental office in two weeks.
At the second visit, your dentist will remove the temporary crown and check the fit and color of the permanent crown. If everything is acceptable, a local anesthetic will be used to numb the tooth and the new crown is permanently cemented in place.
Caring for your Temporary Crown
During the two week period you have your temporary crown, there are some guidelines you need to follow:
1) Avoid sticky, chewy foods which have the potential to grab and pull off the crown.
2) Minimize the use of the side of your mouth that has the temporary crown.
3) Avoid chewing hard foods (e.g. raw vegetables), which could dislodge or break the crown.
4) Slide floss out, rathar than lifting out, when cleaning your teeth. Lifting the floss out, as you normally would, might pull off the temporary crown.
Should your temporary crown come off, you can paste it back on with some toothpaste or temporary tooth cement, which can be found at your local drugstore.