Dental crowns are caps that enclose a tooth or implant. Dental practitioners often recommend crowns as a means of supporting broken, weak or deformed teeth. Dental crowns can also be used to cover a severely worn or discolored tooth. They may also be used in combination with bridges to strengthen a number of teeth. As for the materials that make up the crowns, you have several possibilities, including ceramics and metal. Another option that is now available to some persons is a zirconium crown.