• Crowns are meant to protect the part of the tooth that is seen above the gum line. They are placed there to strengthen the tooth or to enhance its appearance or size. They are also used to secure a bridge or dental implant. There are a quite few different kinds of crowns available, each serving a specific purpose. Our Seattle dentist can advise you on whether or not you will need a crown depending on the type of treatment you are receiving. Often a temporary crown is put in place until the permanent crown is made. Crowns are made of different substances such as porcelain, porcelain fused to metal, metal or resin.