Does your office do the new computer-designed, one appointment CEREC crowns?
Computer-aided design and manufacture (CAD/CAM) of dental crowns is an impressive technological advance. Once an image of a prepared, properly shaped tooth is captured with a specialized digital camera called a scanner, a computer guided milling machine can take a block of ceramic material and grind it into the shape needed to form a crown that fits the prepared tooth. Dental CAD/CAM systems can be purchased for in-office use by a dentist so that the crown is made right where the patient is seated, or they can be purchased by commercial dental laboratories, whose many dentist-customers can have CAD/CAM crowns made for their patients, but with a delay in getting the crown to the patient for delivery from the lab.
Not surprisingly, CAD/CAM systems are very expensive to purchase. It is well known when a dentist purchases such a system how many crowns he will need to produce each month to pay for the system. This creates potential ethical dilemmas, in our view. The first is the case of a tooth that is borderline as to whether it needs a crown. Will the dentist be more likely to recommend a crown than not if he's making payments on a CAD/CAM system? The second is the removal of treatment options for the patient. If a crown could be made with a different material that would be better for the tooth but it is not a material the CAD/CAM system can mill, will the patient be offered the different material or the CAD/CAM crown?
We do not do enough crowns per month in our office to consider purchasing a CAD/CAM system. Our dental laboratory (Chapman Dental Laboratory, University Place, WA) does have a CAD/CAM system, however. Matthew Chapman advises, "What is most important is the amount of data the CAD software is providing the CAM software and the number of axes (Ed.: plural of axis, not a wood chopping implement) the burs can move in and the number of burs used in the milling process. Our Weiland mill and 3Shape scanner and design software is superior to the CEREC (Ed.: the leading in-office system) on many levels" (personal communication, 1/25/2016).