A crown is an artificial restoration that fits over the remaining part of your tooth, making it strong and giving it the shape of a natural tooth. A crown is sometimes known as a 'dental cap'.
Why would I need a crown?
There are multiple indications for crowns. Some of the common ones include:
- To strengthen a tooth after it has had root canal treatment;
- Trauma – to restore broken teeth;
- To strengthen teeth with very large fillings;
- To improve the appearance of discoloured teeth or to improve the shape of teeth;
- As part of a bridge;
- On top of an implant;
What is the process of having a crown fitted?
Fitting a crown generally requires at least two visits to your dentist.
The first visit will involve your dentist taking a mould from your mouth so that a lab can prepare the crown to exactly the size and shape required.
Your dentist will usually also prepare the tooth for the fitting at this time, by clearing away any remaining decay from the affected tooth and sometimes a little reshaping of the tooth is required, so that the crown can be securely fixed at the next visit.
It is very important your dentist explains the risks associated with crown treatment and addresses any concerns that might be specifically related to your teeth.
During the first visit, your dentist might also fit the temporary dental crown, which will be in place until your permanent crown is ready.
Restrictions of crowns
As the temporary crowns are not meant to last, it is important that you are aware of the following precautions:
- Avoid sticky, chewy foods (for example, chewing gum, caramel), which have the potential of grabbing and pulling off the crown.
- Minimize use of the side of your mouth with the temporary crown. Shift the bulk of your chewing to the other side of the mouth.
- Avoid chewing hard foods (such as raw vegetables), which could dislodge or break the crown.
- Slide rather than lift out dental floss when cleaning between your teeth to avoid pulling off the temporary crown.
The second visit to finish the process is often a few weeks after the first, to give the laboratory enough time to create the crown.
Your dentist will fit the crown, and once they are happy with the positioning, colour, size and shape of the crown, it can be cemented into place.
What Problems Could Develop with a Dental Crown?
Once the crown is fitted, you might develop the following problems:
- Discomfort or sensitivity. Your newly crowned tooth may be sensitive immediately after the procedure as the anaesthesia begins to wear off. If the tooth that has been crowned still has a nerve in it, you may experience some heat and cold sensitivity. Pain or sensitivity that occurs when you bite down usually means that the crown is too high on the tooth. If that is the case, you might want to let your treating dentist know of the problem.
- Chipped crown. Crowns made of all porcelain or porcelain fused to metal can sometimes chip. If the chip is small, a composite resin can be used to repair the chip with the crown remaining in your mouth. This is usually just a temporary fix. If the chipping is extensive, the crown may need to be replaced.
- Loose crown. Sometimes the cement washes out from under the crown. Not only does this allow the crown to become loose, it allows bacteria to leak in and cause decay to the tooth that remains. If this happens, the patients are recommended to contact their dentists.
- Crown falls off. Sometimes crowns fall off. Reasons include decaying of the underlying tooth and loosening of the cementing material used to place the crown. If your crown comes off you should contact your dentist's office.
- Allergic reaction. Because the metals used to make crowns are usually a mixture of metals, an allergic reaction to the metals or porcelain used in crowns can occur.
- Dark line on crowned tooth next to the gum line. A dark line next to the gum line of your crowned tooth is normal, particularly if you have a porcelain-fused-to-metal crown. This dark line is simply the metal of the crown showing through. While not a problem, the dark line is cosmetically unacceptable, and your dentist may have to replace the crown with an all porcelain or ceramic one.
On average, dental crowns last between five and 15 years. The life span of a crown depends on the amount of "wear and tear" the crown is exposed to, how well you follow good oral hygiene practices, and your personal mouth-related habits.
Before you go ahead with any treatment, you need to carefully consider the benefits of the treatment and make sure that you are committed to the aftercare required.
Despite of your dentist’s or your own efforts some crowns may fail. However, sometimes the problems you might face might be due to the dentist’s negligence.
Dental Negligence Examples
Besides the failure to properly consent the patient, the dentist may also make the following mistakes that could constitute a negligent treatment:
- The dentist’s failure to advise of alternative treatments;
- Failure to treat decay before placing a crown;
- Failure to check the health of the tooth before placing a crown;
- The dentist’s failure to assess the shape of the crowns resulting in pain and other problems;
- The dentist’s failure to assess the fit and aesthetics of the crowns, resulting in poor dental hygiene, tooth decay and gum disease;
- Lack of care and skill when handling the instruments which can cause trauma to other teeth or gums. This could also result in an infection.