The term "crown" is used to describe the portion of your tooth that extends above the gumline - in other words, the portion of the tooth that can be seen in a healthy mouth. It is also used more colloquially to describe the dental procedure of having a prosthetic "crown" placed over a decayed, chipped, cracked, or otherwise damaged tooth.
With this dental procedure code, the prosthetic crown fitted over the tooth is made entirely of either porcelain or ceramic. A crown constructed of either of these materials yields positive cosmetic results, with porcelain creating a more natural look than the "heavier" look of full ceramic. For this reason, an all porcelain crown is typically used to repair decay on teeth within the "smile-zone," whereas a fully ceramic crown is most often used in the rear of the mouth.
Use of this type of crown is often prescribed when the removal of a lesser portion of the healthy tooth area is desired, as well as when allergies to certain metals may exist.
To prepare for this type of crown, a dentist will first remove any decayed or weakened areas of the tooth, and reduce its overall shape to accommodate the crown. A mold of your bite will then be made, so the custom crown can be fabricated off-site at a dental lab. If desired, a temporary crown can be fitted until the custom crown is completed.