Cerec Crowns are another type of crown that allows the doctor to prep and place the crown in the same visit. Through photography, 3d computer technologies, and what is called a CAD/CAM. The doctor is able to take 3d pictures of the tooth and design on the computer exactly how they want the crown to look. After the crown is designed on the computer, the crown is milled in the office by a milling machine. The crown is made from a solid block of porcelain. The end result is a top quality crown with the convenience of a single visit.