A dental crown is often required for a tooth that is broken or is weakened by a large filling. A previously placed filling can threaten the strength of a tooth and can even act as a wedge which can encourage the tooth to break or fracture. A crown is a full-coverage restoration which acts as a cap or helmet and fully encircles the tooth or dental implant. A crown can be made of a cast metal material such as gold or of tooth-coloured porcelain which is preferred for cosmetic areas. The crown will be sealed or cemented onto the tooth using a dental cement and will remain inside the mouth. It can be flossed around and brushed like a normal tooth. A crown is an excellent long-term treatment option for a heavily restored tooth which improves both the strength and appearance of a tooth.