The (natural clinical) crown of a tooth is the portion of the tooth which is covered with tooth enamel and projects through the gums into the mouth. It is the part of the tooth you can see, as compared to the tooth root which is generally below the gumline. When a dentist mentions a “crown” as an option for repairing a tooth, they are talking about a prosthetic crown.
If a tooth has been extensively decayed, chipped or cracked, and cannot be restored to its proper shape, function and appearance another way, the dentist may recommend placement of a prosthetic crown.
Crowns are most often made in a laboratory by a skilled dental technician, and the process is very detailed. Use of computerized milling devices to make ceramic crowns is becoming more common, but they may not be appropriate in all applications.
The tooth is first prepared for a crown by removing any decay, and filling in any voids. It is then reduced in shape to a tapered stump, which the new crown will slip down over.
Crowns for baby (primary) teeth differ significantly from crowns for permanent teeth, from the shape of the prepared tooth stump, to the way the crowns are made and the materials they’re made of.