You are here:

Dentistry/PFM and cerec crown


Dr. Mike wrote at 2012-01-28 04:01:18
I disagree with your answer about a cerec crown not being as good.  I agree, hold is the best. The problem with a PFMis that there is a strong gold core with a weak feldspar hoc porcelain on top witha flexural strength of only about 90MPa. So you see a fair amount of crowns break off their porcelain as it sheers from the gold coping. If you loose a contact or occlusal contact, you need to replace the whole crown. The new EMAX crowns that can be done with the Bluecam have a flexural strength of about 400 MPa. Hence , they are less likely to break. The anatomy is fantastic and the marginal fit equals that of a lab. Remember, when you take an impression, there is error involved with the pvs, stone, casting.... An optical scan has no distortion..

andy wrote at 2013-07-16 02:16:29
Dr. Carl Misch is the authority in this field. This doctor is just living in 1900s and telling everyone the same answer.

Win wrote at 2014-01-12 17:13:56
Yes but Emax are not biologically inert, read the entire article that they quote from by Brackett, Wataha, and others.  I'm not sure cell damage is worth the risk in the short term and potentially who knows in the long term? Studies have only been in the short term. And the article says that they are NOT not biologically inert. Not biologically inert and not non-cytotoxic as Ivodent would have us believe. See below. Incidentally you may have to search for the article with a less biased engine than Google as it just takes you to the Ivodent excerpt that conveniently leaves out all the damning conclusions. Interesting Google!

"SIGNIFICANCE: Our results suggest that lithium disilicates are not biologically inert, and that many have a similar cytotoxicity dynamic regardless of small differences in composition or processing."

In vitro cytotoxic response to lithium disilicate dental ceramics.

2008: Martha G Brackett; Petra E Lockwood; Regina L W Messer; Jill E Lewis; Serge Bouillaguet; John C Wataha

Dental materials : official publication of the Academy of Dental Materials 2008;24(4):450-6.


All Answers

Answers by Expert:

Ask Experts


Zev Kaufman, D.D.S.


I can answer any question from simple routine dentistry to very complex dentistry with emphasis on reconstructive, cosmetic, and implant dentistry. My expertise is in co-ordination of very complex treatment plans with other dental specialists or as a one-man-team, since I have extensive training in Prosthodontics, Surgical Implantology, and orthodontics.


Over a decade in private practice of Surgical Implantology and Prosthodontics. Founder and owner of Prosthodontics & Implant Surgery of Manhattan, PC. Clinical Assistant Professor at the Post-Graduate Department of Periodontics & Implant Dentistry at New York University College of Dentistry. Lecture weekly since 1999 on advanced Implant Prosthodontics at New York University College of Dentistry Post-Graduate Program in Periodontics & Implant Dentistry. Former clinical assistant professor of Dental Radiology at the NYU College of Dentistry. Former clinical and lecture faculty at Lincoln Hospital, Dental residency program. Former clinical and lecture faculty at St. Barnabas Hospital (Bronx, NY) dental residency program. Lecture nationally on Prosthodontics and Implant Dentistry.

Memeber of the American College of Prosthodontics. Memeber of the Acacdemy of Osseointegration. Member or the Omikron Kappa Upsilon (OKU) Honors Dental Society. Member of the American Dental Education Association.

Graduated with Honors from New York University College of Dentistry. Post-Graduate training and certificate in the specialty of Prosthodontics. Post-Graduate training and ceritificate in Surgical and Prosthetic Implant Dentistry. Honors-program in Comprehensive and Applied Practice Management. Honors-program in Orthodontics.

Awards and Honors
NYU Cervice award to the community. OKU honor society. National Dean's List. National Who's Who.

©2017 All rights reserved.