pfmsAs we all know, we have a lot of new materials to pick from – and yet sometimes “old friends” are the best thing for us to remember.

Two of those old friends I am referring to are PFMs and full gold crowns.  While the use of PFMs and full gold crowns has decreased, there are still situations where PFMs are the restoration of choice. First let’s talk about PFMs. While blocking out dark preparations is certainly possible with high opacity eMax ingots, the input I have received from my lab is that there is still a chance of show-through with extremely dark preparations like those pictured.

When are PFMs the Best Choice?

Cases like this, while extreme and likely rare in most practices, are examples of cases in which PFMs can be your best choice. This is due to the fact that the metal coping will completely block out all the underlying discolored tooth structure and take it out of play. Of course, one of the big challenges when using PFMs, particularly in the esthetic zone, is that they require a technician who is used to working with them and can predictably deliver a highly esthetic result

The reason I say this is a challenge is with the increased popularity of all ceramics, the number of technicians able to predictably deliver highly esthetic PFM restorations that can match the esthetics of an all-ceramic crown has greatly decreased.  Another huge challenge is that while typically both a PFM and all-ceramic crowns require the same amount of reduction for an ideal result – at least if you ask the technicians I work with – the results with PFMs are more severely impacted by minor short comings of room for porcelain than all-ceramics.

The other “old friend” I would like to discuss is a full gold crown.  While they are also decreasing in popularity, perhaps even more so than PFMs, they are a great choice in heavy bruxers when esthetic demands allow. Sure, we have things like full contour zirconia and eMax that do very well, but the fact of the matter is they still can and do fracture on occasion while gold does not.  Sure, gold wears and your patients can even wear a hole though it over time but the simple fact is you can spot and deal with that easier than if your patient’s crowns fractures in half suddenly.

John R. Carson, DDS, PC, Spear Visiting Faculty and Contributing Author  www.johncarsondds.com



Comments

Commenter's Profile Image Larry Langer
November 19th, 2014
I'm totally on the same page. I still do mostly pfm's, especially when endo teeth are involved. This is because I am a fanatic about having a ferrule, which is not always possible without a bevel. Anterior cases I do 180. Degree butt joints. Also, if there is limited inter arch space, or concerns with bruxing, love to have lingual metal. I use hi noble met al on all these cases, I have found that some people have chronic inflammation from semi precious. eMax is a beautiful restoration, but they need to be bonded, and I wouldn't splint them. Not a big zirconia fan (esthetics and retention), so my go to is always PfM crowns. Have a great lab (Jason Kim) using creation feldspathic porcelain...crowns are beautiful! Larry
Commenter's Profile Image John Carson
November 20th, 2014
Thanks for comments Larry! I know lots of folks are still doing lots of PFMs as well, yet others don't use them at all. For myself the use of PFMs is pretty much reserved for cases like this where my ceramist feels it is need to assure that the prep color is taken completely out of play, on everything else we are typically using eMax or Zirconia, simply because eMax means we can limit the amount of veneering porcelain and minimize risk of chipping, as for Zirconia instead of metal, well that's simply due to the fact he (my ceramist) prefers to work with that which also works well for my patients since I have only ever used hi-nobel metal for PFMs and that drives costs higher so if my ceramist like zirconia more and I can pass savings along the patient it's a win-win.
Commenter's Profile Image John Carson
November 20th, 2014
I forgot to add that you can cement eMax with RMGI cements. While Ivoclar will tell you they prefer you bond it they will also tell you it does really well with RMGI cements.
Commenter's Profile Image Klara
December 7th, 2014
PFM's are great if you use porcelain margin in anterior cases.