crowns - some technical information

A crown is a restoration that covers, or “caps,” a tooth to restore it to its normal shape and size, strengthening and improving the appearance of a tooth. Prosthetic crowns are made of metal, porcelain fused to metal substrates, or tooth colored restorative materials. Crowns are necessary when a tooth is extensively broken down and fillings won’t solve the problem. Root canal treated teeth should generally be crowned to prevent fracture of the tooth. If a tooth is cracked, a crown holds the tooth together to seal the cracks, to prevent further damage to the tooth. Crowns are also used to support a large filling when there isn’t enough tooth structure remaining, attach a bridge and cover badly shaped or discolored teeth.

how is a crown placed?

The tooth is anesthetized and prepared for the crown by removing any decay or weakened areas. The remaining tooth structure is then reshaped to meet proper crown preparation design. If necessary, a restorative material, usually a composite resin, is added to the remaining tooth structure to ensure that the prosthetic crown will have a good foundation. This procedure is called a “build-up.” If the dental decay is found to have gone deep to an extent where the living portion (dental pulp) is affected, root canal procedures are essential prior to completion of the crown / bridge procedures. This is to avoid complications from pulpal infections after the tooth has been crowned.
After the tooth is prepared, impressions of teeth and gums are made and sent to the dental laboratory for the crown fabrication.During the second appointment, the new crown is placed on the tooth. Adjustments may be required to exact the perfect fit, so that the crown will feel comfortable in the mouth and will conform to the bite. When the crown fits seamlessly and contacts the neighboring teeth correctly, the crown is cemented on the tooth.

Will it look natural?
Yes. The dentist’s main goal is to create crowns that look like natural teeth. That is why dentists take an impression. To achieve a certain look, a number of factors are considered, such as the color, shape, length and bite of your natural teeth. Any one of these factors alone can affect your appearance. If you have a certain
cosmetic look in mind for your crown, discuss it with your dentist at your initial visit. When the procedure is complete, your teeth will not only be stronger, but they may be more attractive. Metal crowns will have a metallic finish. However, it will resemble a normal tooth in shape and size.

What is the difference between a cap and a crown?

There is no difference between a cap and a crown.

How long do crowns last?
Crowns should last approximately 5-8 years. However, with good oral hygiene and supervision most crowns will last for a much longer period of time. Some damaging habits like grinding your teeth, chewing ice, or fingernail biting may cause this period of time to decrease significantly. The type of material used in crown fabrication also affect the life of crowns.

How should I take care of my crowns?
To prevent damaging or fracturing the crowns, avoid chewing hard foods, ice or other hard objects. You will also have to avoid teeth grinding. Besides visiting your dentist and brushing in the correct manner twice a day, cleaning between your teeth is vital with crowns. Floss or interdental cleaners (specially shaped brushes and sticks) are important tools to remove plaque from the crown area where the gum meets the tooth. Plaque in that area can cause dental decay, gum disease and cause the restoration to fail. Regularly scheduled examinations and hygiene appointments must be adhered to.