A dental crown is placed over a tooth when a large cavity threatens the health of a tooth, or it has become badly damaged or decayed. The dental crown, also known as a cap, is a tooth-shaped cover placed directly over a tooth. Crowns have many purposes, but their main role is to help restore a tooth’s functionality and appearance. If a tooth is weak from decay, a crown is commonly placed on top of the tooth to protect it from breaking. In cases where a tooth is already cracked, the dental crown holds the pieces together. The crown can also help repair the broken tooth. In cases where there is not a lot of tooth left, but there is a lot of filling, the crown can be used to cover and support it. They’re also used to hold a dental bridge in place, to cover severely discolored teeth, and to cover a dental implant.