A crown is a porcelain or metal "cap" that protects a broken-down or fractured tooth from further deterioration. It works like a barrel hoop to hold a tooth together. A crown is necessary when a tooth has a majority of structure lost due to decay or fracture, when the tooth is cracked, or when a root canal therapy has been performed. Crowns may also be placed for cosmetic reasons or to correct a misshapen tooth.
Same Day CAD-CAM Crowns
At our office, we use computer technology called CAD-CAM to design and fabricate our crowns in–office. With this system, we have eliminated the need for impressions and temporaries. The impression is made digitally by the computer “reading” the tooth, and the actual crown is fabricated in office in a computerized mill in our laboratory and delivered to the patient in one visit. Our CAD-CAM system can also be used for inlays, onlays, and porcelain veneers.
One of the most interesting developments regarding the CAD-CAM restorative system is that research has found that the ceramic material used by the system is very strong, long lasting, and highly biocompatible. The crown material made by the company we use for our ceramic crown blocks is made of lithium disilicate under precise manufacturing conditions, resulting in an amazing dental material.
A crown can last fifteen - twenty years or longer if properly cared for. The important thing to remember is that decay can occur even if the tooth is covered with a crown. The margin where the crown meets the tooth must be kept clean or decay can take hold and undermine the crown. Proper oral hygiene, use of fluoride, and regular dental checkups will minimize the problem.
What a Crown Looks Like
A porcelain crown should look just like a tooth. We generally use all-ceramic crowns at this office fabricated with our computer aided in-office system. With this system, we perform our own characterization and glazing of the crown in our laboratory, allowing us to artfully match the crown to your existing teeth, without the guesswork involved when sending out to an outside lab.
Before we cement a porcelain crown, we ask for the patient's approval of the way it looks. Patients always have the option of bringing a spouse, family member, or a friend with them to approve aesthetics of a front tooth crown. It is important to carefully evaluate aesthetics and express any concerns about cosmetics before the crown is cemented. To make cosmetic changes after a crown is cemented in place is likely to involve remaking the crown.
Possible Complications for a crown
Sensitivity or Pain
Some sensitivity is normal for twenty-four hours. If pain persists or is severe, we need to know.
Because crowns are placed on teeth that have suffered major trauma through decay or fracture, there is a possibility that the tooth could abscess in the future, even though there may be no indication at time of crown placement.
A crown may need occlusal adjustment after placement. Because a patient is anesthetized in the office, he or she may not feel a discrepancy in the bite until later when the anesthetic wears off. If a crown does not feel right when chewing, a patient should return to the office for an adjustment as soon as it is detected. Failure to correct this issue can result in unnecessary discomfort for the patient.
Gold, Porcelain, or Composite Inlays
While most fillings are direct placement procedures (drilling out decay and immediately filling with restorative material), indirect restoration may be an option for restoration.
With an inlay, the preparation is made to clean out the decay, and an impression is taken of the tooth. This impression is sent to a lab and a restoration is cast or fabricated in the material of choice. The patient returns after the lab work is completed and the inlay is fitted into the prepared tooth and cemented.