Where fillings are utilized to just cover a small portion of a tooth, a crown (or cap) encases the entire visible portion of a tooth. In effect, the crown acts as the tooth's new outer surface.A dental crown is used when a tooth is decayed or broken to such an extent that fillings aren't able to repair the problem. The crown is able to provide a protective shell around the damaged or decayed tooth to strengthen it, as well as to improve the appearance of the tooth. They can also help restore a tooth to it's original shape, and are used commonly for teeth that have been broken. While crowns come in different materials, the most common crowns typically have some mixture of porcelain in them to give them a look and feel similar to a natural tooth.
How it's done: