CEREC uses CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) technology, incorporating a camera, computer and milling machine in one instrument. Dr. Duboff uses a special camera to take an accurate picture of the damaged tooth. This optical impression is transferred and displayed on a color computer screen, where he uses CAD technology to design the restoration. Then CAM takes over and automatically creates the restoration while the patient is still in the dental chair. Finally he bonds the new restoration to the tooth. The whole process usually takes about one hour.