Crowns can be entirely metal or ceramic, or porcelain fused to metal (PFM). Metals include gold alloy; other alloys, such as palladium; or a base-metal alloy, such as nickel or chromium. All-metal or PFM crowns are good choices for back teeth, because they are stronger. PFM and all-ceramic crowns look just like natural teeth.

A crown is a tooth-shaped cap which is placed over a tooth that is badly damaged or decayed. A crown is made to look like your tooth and is sometimes referred to as a 'cap.'