Porcelain Crowns are all white, therefore best for cosmetic reasons.
Crowns usually are made with metal and porcelain, but this may appear as a dark line along the gums. However, porcelain and zirconia have no metal so they are all white and therefore they are the best crowns for cosmetic reasons. A crown completely encircles or covers a tooth or dental implant. Crowns are often needed when a large cavity have been filled and only a small part of the tooth remains. In order to protect the remaining tooth structure from breaking or to save a tooth that has already broken, a crown can be placed on the tooth. They are also used to improve the appearance of teeth and also to correct the alignment, shape and size of teeth. They are typically bonded to the tooth using a dental cement.