Unlike dental implants, a dental crown is used to cover or “cap” a damaged tooth. Besides strengthening a damaged tooth, a crown can be used to improve its appearance, shape or alignment. A crown can also be placed on top of an implant to provide a tooth-like shape and structure for function. Porcelain or lithium disilicate crowns can be matched to the color of your natural teeth. Other materials include gold and metal alloys, Zirconia, . These alloys are generally stronger than porcelain and may be recommended for back teeth. Porcelain bonded to a metal shell is often used because it is both strong and attractive.