Crowns are used when a tooth is no longer strong enough to function without breaking. This could be due to heavy restoration, weakening through Root Canal Therapy or large breaks in a tooth due to an accident.
Crowns are also useful in cosmetic dentistry when teeth are discoloured, malformed or wrongly positioned.
The making of a crown requires two appointments, normally two weeks apart. Usually at the first appointment an impression is taken of your existing tooth, this is to enable a temporary to be made. Any defective tooth or filling is then removed and the tooth is re-shaped to create a foundation for a crown.
Another impression is then taken to enable the lab to construct a replica of the tooth preparation in order to fabricate the crown. A temporary crown is created in the surgery and placed over the base both to protect the tooth and for cosmetics.
At the second appointment the crown that has been lab fabricated to match the foundations in your mouth and the shade of your other teeth will be fitted. During the gap between appointments you may be required to visit the lab to ensure an exact shade match. As long as the fit, colour and shape are all up to standard then the crown will be bonded with the appropriate cement.
Materials used in restorations involving lab fabrication –
Inlays, onlays, crowns, veneers, bridges
Porcelain bonded to metal
Composite / Acrylic
There are many factors that determine the choice of material used – some are the position, cosmetic requirement, strength of bite and personal preference.