When a tooth is broken down, has had multiple large fillings, or has had root canal therapy, we recommend coverage of the tooth with a crown. Dr. Isakson's opinion is that a crown is actually a preventive measure, that is, it prevents further breakdown and possible loss of the tooth. Placement of a crown requires reduction of the top and sides of the tooth. An impression of the area is then made so that the crown can be made to fit precisely. After the impression, a temporary crown is placed to protect the tooth while the new crown is being fabricated. A missing tooth is often replaced with an implant, however, a crown on either side of the gap may be used to hold a pontic, or false tooth, which replaces the missing tooth. This " bridge" functions very well and has a very natural appearance.