The Best Way to Prep a CEREC

New users sometimes get confused as to how to prep a full crown for a CEREC restoration. Frankly, if you follow these simple rules, you can just prep as you have always prepped your crowns:

• Avoid undercuts in your preps
• Avoid knife edge or beveled margins

If you do those two things, then all you need to do is just prep like you normally would prep for an all-ceramic crown with 1 mm axial reduction and 1.5-2.0 mm of occlusal reduction.

But I think you will find that if you are using a CEREC, you can modify your preparation to save the most amount of tooth structure. The reason we have prepped the axial walls in the past was for retention and resistance form. We cemented metal ceramic crowns as those could not be bonded in place. The need therefore to have proper wall length was critical because you needed the wall length to maintain your restoration in place.

Fast forward to the adhesive bonding era and you could simply prep to conserve enamel but because you still had to send the case to the laboratory, some traditional retention and resistance form was still needed to keep the provisional in place.

Today, with CEREC and no provisionals, if the tooth allows it, the photo below is representative of my full crown preparation. If I don’t need to prep the lingual, I avoid it. If I don’t need to prep the walls, I avoid it. Because we are bonding our restoration on immediately and there is no provisional involved, there is no need to prep to keep the provisional in place. I can keep the maximum amount of tooth structure in place and be as conservative as possible.

If the prep looks a bit scary to you and you think your restoration will fall off, by all means continue to prep the way you have been prepping. But I promise you that this is easier to prep, easier to marginate and easier to finish and better for the tooth. Don’t forget the key with all CEREC preps – keep your margins “smooth as glass.” I will share in a future blog what I use to polish my margins and why it’s critical.

About Post Author

SAMEER PURI DDS

Sameer Puri, D.D.S. runs a successful private practice focusing on esthetic and reconstructive dentistry. His professional affiliations include the American Dental Association, the Academy of General Dentistry, the American Academy of Cosmetic Dentistry and the California Dental Association. A graduate of the University of Southern California, School of Dentistry and the Advanced Education in General Dentistry residency from the University of Tennessee, Dr. Puri serves as the Director of CAD CAM at the Scottsdale Center for Dentistry. He is also the founder of www.cerecdoctors.com a website dedicated to CEREC online education where clinicians can learn the ins and outs of CEREC dentistry from basic training to more advanced techniques such as anterior esthetics. The website has become the standard of CEREC training and is the largest online CEREC resource in the world. Patterson Dental found the content so valuable to the CEREC user, that they approved the website to be used with the CEREC Advanced Training Vouchers, the first time any educational medium outside of a standard training was approved to do so. Dr. Puri has been published in numerous professsional journals and magazines. His aesthetic techniques and results have been used in manufacturer brochures and advertisements. Dr. Puri is also a consultant to various manufacturers to help them improve their products and help develop new products for the dental industry. He is married to his wife of 14 years and is the father to two beautiful girls.

http://www.cerecdoctors.com