Crowns, also known as caps, are attached to an existing tooth. Made from porcelain, certain types of metals and other materials, they are custom-fit to your mouth. Usually a crown is needed after extensive repair work has been done, such as a root canal, after a large cavity has been filled or if a tooth cracks or breaks.
Bridges are like crowns, except that they cover and replace more than one tooth. Dental bridges are used to permanently fill in a space where multiple teeth are missing. The teeth on either side of the gap are prepped to serve as anchors for the false tooth that will be placed in the gap. The bridge spans all of the teeth and is permanently attached to your mouth.