It seems that nothing lasts forever, and with the passage of time you often start to think about those dental crowns that you had fitted all those years ago. Maybe it's time to replace? What situations could lead to a need to replace your crown?
How Long Should they Last?
It's important to realise that (for crowns that were fitted some time ago) the average life expectancy should be between five and 15 years. However, this will depend a lot on your "bite" and how those teeth come together, as well as your oral hygiene practices.
Beware of Fractures
When you bite, you exert a tremendous amount of pressure and over time this can cause damage to the porcelain part of the crown. Any damage can cause a tiny fracture all the way through. If this situation has arisen, it's not possible to repair that crown and it has to be replaced instead. Most often, dentists will fit a different type of crown called "fused to metal" these days, especially for back teeth where the pressure is even greater.
Root Canal Complications
If at any time you should need a root canal in the area where you have had a crown fitted, then your dentist has two options. Firstly, today's technology allows them to create a perforation in the crown in order to access the area for treatment. Sometimes, this can cause the actual structure of the crown to be affected and this may not allow a filling to be placed following the root canal work. In this second case, the crown may have to be removed before treatment, but it can be replaced afterwards.
Wear and Tear Could Signal Crown Replacement
You may have noticed that the teeth opposite the crown are exhibiting more wear and tear than is normal. This could be because they are coming into contact with a crown made of more abrasive and harder material. In this case, ask the cosmetic dentist whether you can replace the crown with materials that are less likely to cause this damage over time.
Outer Damage May Be Repairable
Fused to metal crowns are made from porcelain, with a metal "jacket" designed to actually cover the tooth. The porcelain element is the outer layer, which is fused to that jacket and gives it the proper appearance. Usually, damage will occur to the outer porcelain and not the inner metal jacket. If your dentist notices only damage to the porcelain, then that can be repaired, but if there should be any issue with the metal jacket beneath, then that calls for a full crown replacement.
Stop Clenching for Longer Life
If you have a habit of clenching your teeth at night, then you should ask the dentist to help you stop this behaviour. Otherwise, over time the crown can be perforated, which will allow dental plaque to penetrate and potentially form a cavity.