A crown is a laboratory made restoration that covers all or the majority of an exposed tooth. Crowns provide additional strength to teeth and are often the best way to save teeth. In addition they can also be used to alter the shape, or colour or orientation of teeth.
A bridge is a series of crowns used to replace one or more missing teeth. It consists of an artificial tooth/teeth anchored to the natural teeth on each side of the gap.
Structure of crowns and bridges
A crown can be made of metal [usually gold], porcelain or porcelain veneered to the metal. Today there also new cutting edge technologies allowing us to fabricate crowns in “white gold” made from materials such as Alumina and Zirconium. These materials are similar to porcelain in appearance but are significantly stronger. Gold alloys are used for their strength, hardness and durability and are still very often recommended for use on especially 2nd molar teeth which generally have little aesthetic value but need to withstand the most extreme grinding an crushing forces.
All porcelain restorations are strong and can be made to match the shade of the surrounding natural teeth. The smooth surface of the porcelain makes it resistant to staining. The superior aesthetics and improved strength of the modern day ceramics make all porcelain crowns the natural choice for front teeth crowns in most circumstances.
Technique for crowns and bridges
Once the tooth is appropriately shaped an impression is made. This impression is sent to the dental laboratory where the technician will make a model that is an exact replica of the tooth in the mouth. It is on this model that the technician will fabricate the new crown. During the period of manufacture you will have a temporary crown fitted to the tooth. At the fitting appointment the temporary crown is removed and the after checking for accuracy of fit, colour and relationship to the adjacent and opposing teeth, the permanent crown is glued or bonded into place.