What You Should Know About Crowns
People need crowns for a number of reasons. Often, however, they learn about crowns when they’re in the dentist’s chair and are not in the best position to start thinking about options.
Crowns can protect a weak tooth from breaking; they can be used to restore an already broken or worn tooth; they can cover and support a tooth with a large filling; or they can cover misshapen or severely discolored teeth. Different materials for crowns may be used for different purposes.
Traditionally, metals were used for crowns, especially in rear teeth where they were not visible and where their durability could withstand the forces of biting and chewing. Feldspathic porcelain and resin have also been used, but are less strong than metal. Today’s ceramic, which is almost as strong as the metal crown, allows a better fit, with greater durability, in addition to being more cosmetically appealing than previous standard porcelain fused to metal crowns. The problem with these earlier crowns was the “black line” often visible as the gum tissue receded over the years.
Today’s state-of-the-art ceramic crown is made by computer generation, which can be done in one of three ways. In the first way, the dentist takes an impression using standard impression techniques and sends it to the laboratory, where it is scanned and computerized. In the second way, the dentist makes a computerized image in the office and sends it to the laboratory via the Internet. In the third way, the computerized image is generated in the office and the crown is actually milled there.
All three techniques produce the same precisely accurate ceramic crowns. Patients like the computer-generated ceramic crown because it’s natural looking and is compatible with tissue in the mouth. It’s anti-abrasive and also plaque- resistant. The computer generation allows for an extremely accurate fit. Because of this accuracy, a tremendous amount of time is saved in fitting and seating the crown, making for a more pleasant and comfortable patient experience.
If you need a crown, the durability of the ceramic crown is making it the crown of choice for most restorative and cosmetic procedures. A 2008 article in the Journal of the American Dental Association reported that after six years of wear, more than 90 percent of all ceramic restorations remained intact. This is a far greater long-term success rate than we see with crowns made from other material.