Dental crowns are considered restorative when they improve oral health and function, such as when crowns are used as an artificial tooth over a dental implant. Crowns are also often used to repair teeth that have been damaged from grinding and clenching or some other kind of injury.     Crowns are considered cosmetic dentistry when the crown is used primarily to improve the appearance of your smile, such as covering an uneven or misshapen tooth. Like veneers, crowns require some of the tooth to be filed down, but crowns require more of the natural tooth to be removed before they can be placed.