A crown is basically a cap that is placed over what is left of a tooth. In most cases, a crown is used to fill an opening between teeth where a tooth has been severely damaged, broken, or lost. Temporary crowns may be made of almost any material, but more than likely they will be manufactured using a composite resin. Permanent crowns are normally made of a high grade, dental porcelain that is designed to last for several years without cracking, chipping, staining or breaking. Crowns normally take the same shape and color of the teeth they are replacing in the mouth.