Peter Gardell Time after time we have patients walk into the office with old PFMs that are a little lacking in the esthetic department. It is remarkable how thin some of these restorations have been made. The lab tech really displayed some skill to fit spacer, metal, opaque and porcelain all within .7 mm. Funny thing is when they have to be remade we cut them off and are still afraid to prep more. This locks us into creating a restoration with questionable esthetics and strength. One of the principles of esthetic dentistry is we need a certain thickness for our ceramic. If you cheat on thickness, be prepared to suffer the consequences.
When working with these old restorations I like to use the tip Dr. Mark Fleming talked about in a recent blog use the 330 bur to gauge the depth. This bur saves me excessive wear and tear on a Meisinger Router Bur, cuts faster through the metal, both precious and non-precious metals. I want to save on both time and money!
My method is to quickly slice to establish the depth, pry the two halves apart and proceed to refine the prep properly.
The other issue with these replacement crowns is making sure you refine the prep to remove the bevel that many of these restorations have. CEREC technology can be very precise with its milling but unless you are using a hybrid material such as Lava Ultimate you will be disappointed with the chipping that can result.
Don’t take anything for granted. A patient walks in your office with an ugly PFM I can guarantee that it is under prepared.
Commit to success for your restoration. Prep it like you own it because, in essence, you do.
Prep for excellence!
