Crowns and bridges in dentistry are used to repair or replace teeth in which excessive damage or decay has occurred. Crowns and bridges are typically fabricated using the indirect method because they require significant amounts of heat and processing that cannot be performed inside the mouth. The indirect method is done outside the mouth by a dental technician in a dental lab.
Impressions are taken of the existing teeth using an elastic material which, when removed, retains the shape and form of the dental structure. From this negative mold, a cast can be made, also known as a positive. This positive cast is then used in the dental lab to create the crown or bridge that will eventually be fitted to the patient’s teeth. In order to fit the dental restoration, a significant amount of material must be removed from the existing tooth or teeth.
There are several types of dental crowns and bridges depending on the situation and application:
PORCELAIN-FUSED-TO-METAL CROWNS
When a tooth will remain visible, porcelain-fuse-to-metal crowns are the preferred method. These crowns use a metal shell onto which is fused a porcelain finish, giving a more natural appearance. The metal provides the strength required while a partial veneer covers part of the crown, providing a more aesthetically natural appearance.
FULL GOLD CROWNS
FGC, or full gold crown, is a type of dental restoration that uses an indirect method of fabrication to fully cap a tooth. A gold alloy material is typically used consisting of gold and a blend of other materials such as platinum, palladium, silver, copper and tin.
IMPLANT SUPPORTED CROWN
In extreme cases, a special implant can be fitted which is then capped with an artificial tooth – the crown. This method completely replaces the old tooth with artificial material and is, in fact, one of the few medical applications in which the boundary between the inside and the outside of the body is permanently crossed.
DENTAL BRIDGE
A bridge is a special type of dental restoration that involves artificially manufacturing replacement teeth to literally bridge the gap between remaining teeth. If one or more teeth are missing or excessively damaged to the point that they must be removed, a bridge can be manufactured in a dental lab that will then be bonded in place to maintain the integrity of the patient’s mouth.
