What is a dental crown?
A dental crown, commonly called a "cap," is a tooth-shaped restoration that is made by a machine usually in a dental laboratory. It is designed to cover the entire tooth and strengthen the tooth.
Why might I need a dental crown?1
There are different reasons why your dentist may recommend a crown for one of your teeth. Sometimes a crown is placed over a tooth that has had a root canal, or one that has had a large filling, to help keep the tooth strong for biting and chewing. Crowns can also be used to hold a dental bridge in place or to cover a dental implant. A dentist may also recommend a crown to protect a weak or discolored tooth or to cover a broken one.
What types of materials are used to make crowns? 2
There are a wide variety of materials that your dentist may recommend for a crown.
- Metal Alloy - Dentists may choose to use a metal alloy (a mixture of metals) for a crown, including gold alloy (also known as noble or high noble) or a base-metal alloy, which gives a silver appearance. Metal crowns are very strong and therefore tend to last longer than other crown materials.
- Porcelain (including Ceramic and Glass-Like materials) - This type of crown is the most natural looking since its color and translucency can be designed to closely match surrounding teeth. Because it is not as strong as metal, porcelain crowns may break or fracture due to heavy biting or grinding.
- Porcelain Fused to Metal - Your dentist may recommend a porcelain fused to metal crown. Covering a metal crown with porcelain creates a more natural looking crown. The metal provides an additional level of strength to the crown, even though the porcelain may still be prone to fracture.
Crowns and Onlays Materials OptionsWhat is involved in placing a dental crown?3
Placing a permanent dental crown typically takes two dental office visits, but some new technology allows crowns to be produced in one day. During the first visit, the dentist will numb the tooth and surrounding gum tissue, and then shape the biting surface and sides of the tooth to allow space for the new crown (restoration) to be placed. An impression of the prepared tooth and jaw is taken as well as the opposite jaw may also be taken to help create the proper bite relationship. If the tooth is very decayed or otherwise too small to hold the crown, the dentist may "build up" the tooth to hold the crown.
Once the tooth is shaped, the dentist makes an impression of the tooth to send to the dental laboratory that will make the custom crown. If the dentist is placing a porcelain or porcelain fused to metal crown, he or she will also determine a shade of porcelain to match the surrounding teeth. During this first office visit, the dentist will make a temporary crown to cover the prepared tooth until the permanent one is ready. This temporary crown is typically made out of a plastic-type material, and your dentist may ask you to refrain from chewing gum or sticky substances while your temporary crown is in place.
At the second visit, the dentist will remove the temporary crown and test the fit of the new crown. If the new crown fits and the color is correct, the dentist may numb the tooth and surrounding gums and cement the crown in place. The dentist will then evaluate your teeth to make sure the crowned tooth fits with the bite of your other teeth.
After the new crown has been placed, you may need additional dental visits to adjust the crown so it fits comfortably.
Will I need a root canal if I get a crown?
No, not all teeth that get crowns need to have a root canal. Normally if a root canal is needed, the root canal should be completed before a crown is permanently placed on the tooth. Typically, teeth that have had a root canal treated do need to have a crown placed on the tooth.
How long is a dental crown expected to last?
Contrary to popular belief, dental crowns don't last forever. But with good care they can last a long time! Current research shows that more than 90% of crowns will not require major treatment within five years, and 50 to 80% of crowns will last between 15 and 20 years.4 It's important to remember that just like a "real" tooth, the life of your crown depends on how you care for it. You should continue to follow good dental hygiene practices including brushing twice a day, flossing, and seeing your dentist on a regular basis. If you tend to clench or grind your teeth, ask your dentist how this could affect your crown. In general, you should try to avoid chewing hard or sticky foods, which may cause your crown to break or come loose.
Questions to ask your dentist about dental crowns:
- Are there any other treatment options you would recommend instead of a crown?
- What type of material do you recommend for a dental crown and why?
- Are there any special instructions I need in order to best take care of my dental crown?
- I'd like to understand what my potential costs will be. Can you please obtain a pre-treatment estimate from my dental insurance carrier?
1Oral Health Topics A-Z, American Dental Association. Accessed 5/13/09.
2Comparison of Indirect Restorative Dental Materials, American Dental Association. Accessed 5/13/09.
3Dental Crowns. Cleveland Clinic Center for Health Information. Accessed 5/13/09.
4Bader JD, Shugars DA. Summary Review of the Survival of Single Crowns. General Dentistry. 2009; 57(1): 74-81.
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