Crowns are full coverage restorations that are used to cover a tooth that has fractured, is likely to break, or is too broken down to be restored with a filling. They are most commonly done after root canal treatment, or when a large filling wears out. Crowns also serve an aesthetic use, and are applied when a discolored or stained tooth needs to be restored to its natural appearance.
It takes two appointments to restore a tooth with a crown. During the first visit, decay is removed from the tooth and the tooth is shaped to accept the crown. The doctor performs a crown buildup procedure on the tooth if more strength is needed to preserve the integrity of the tooth. An impression is made of the tooth for use in fabricating a crown. At the end of this appointment the patient is fitted with a temporary crown.
Between the two visits the crown is made off-site at a dental laboratory. Most crowns are now made of high-strength zerconia material, a ceramic like material milled to detailed specifications. The length of time between the two visits is usually three weeks.
In the second visit the temporary is removed, and the permanent crown is adjusted and cemented in place.
With proper care, a good quality crown could last up to eight years or longer. It is very important to floss in the area of the crown to avoid excess plaque or collection of debris around the restoration.
Certain behaviors such as jaw clenching or bruxism (teeth grinding) may shorten the life of some crowns. Moreover, eating brittle foods, ice or hard candy can compromise the adhesion of the crown, or even damage the crown.