Dental crowns are used to repair teeth which are so badly damaged or decayed that they require a solid encasement to hold the tooth together. Crowns can be made of metal or a tooth-colored ceramic. Tooth-colored crowns must be thicker than metal crowns to withstand bite stress, so the tooth needs to be reduced more for those. If only a portion of the tooth is damaged, it may be an option to cover only the damaged areas. A partial crown or onlay can be designed that covers enough of the damaged tooth, yet minimizes the amount of healthy tooth structure that needs to be removed. Advances in adhesive dentistry allow ceramic onlays and crowns to be bonded to teeth with less tooth removal than was once possible. Some crowns and onlays are now created with a computerized milling machine. ~ Dental professionals can license more videos for their websites at