Crowns (Caps) and Bridges
In dentistry, crowns (caps) and bridges refer to the restoration of natural teeth that have been damaged, decayed or lost. A crown can be made to restore an individual tooth damaged by decay or fracture back to its original form and function, while a bridge is used to replace one or more missing teeth. These restorations are cemented onto the teeth and are referred to as “fixed” dentistry as opposed to a restoration of missing teeth with a removable appliance or partial denture.
Both procedures require the use of a local anesthetic preparing the teeth: They are pain free! With a crown, only the damaged tooth is being prepared.
With a bridge, the adjacent teeth must be prepared in a certain way. A badly decayed or broken tooth may require that the tooth needs a build-up or sub filling before the crown can be fabricated. In our office, we never use mercury fillings as build up materials as commonly seen. With a fixed bridge, the prosthesis will span the area of a missing tooth while the two or more adjacent supporting teeth – called abutments – will hold the replaced tooth in its place to fill the gap.
It is an easy and very predictable procedure. I have done thousands of three unit bridges replacing one missing tooth only (see picture) or up to ten unit bridges. Crowns and bridges can be made of several materials. Full gold crowns are normally done on the very last teeth in the mouth where strength is most important and appearance is less important. While cheaper non-precious metals and lower quality alloys are available, I use “very high noble gold” as a substructure under the existing porcelain crowns.
The picture above shows 3 types of crowns
Left : All porcelain crown, no metal inside. The most esthetic solution.
Middle : Porcelain fused to gold. Very biocompatible. No grey margin around the gum line.
Right : Porcelain fused to metal inside, grey metal will show grey margin around the gum line after a few years.
Porcelain is layered and fired in a ceramic oven at over 2000 degrees, till the desired shape and size is achieved. Most of my crowns are porcelain crowns, since esthetics is of the outmost importance for most of my patients. The key to success is not only a talented dentist but also an excellent dental laboratory with an artistry dental technician.