Sent: Wednesday, December 28, 2005 12:47 AM
Subject: [roots] a crown prep.....
Thatís it...Radiosurg was used on the gums - Craig
Great photo! That one jumped out at me :)
I'll show Cliff - Phyllis
Since he is an endo guy..remind him that a crown prep is where you
grind the tooth down so that you can put a cap on the tooth!......
KIDDING!!!!! - Craig
Nice prep. I tend to be a bit more aggressive the older I get. Guy
Nice prep Craig and yes Guy, the more you use a scope for restorative
the more conservative your preps become. This was gold right Craig?
I have been doing these for about 4 years now and the lab handles the
minimal reduction just fine and the crowns come out looking awesome.....
I have talked to the lab and they don't see it as a problem....IE:
they have not asked for more reduction.....
Again, the crowns look awesome in the mouth... craig.....
Dude, you are just going to have to take my word for it that they
don't come out bulky or over contoured.....
If you can empathize with my lack of energy towards the cause and accept
this VERY VERY similar case in it's place, it would please me greatly....
It is an upper first premolar prepped the same way as the one I just
showed. The right photo is the before photo to the lab and the left
photo with the bloody gums is the final restoration. I have xrays for
the case, but they are not digitized at this time. Can you accept my
word that the case is not over bulked or over contoured?
The preps work my friend. They work.............
And the blood is real in the photo.... :-)!...Craig
Ah, letís qualify that. Mark and I have NOT advocated a feather edge
on any all ceramic restoration including wolceram for some time now.
Apparently glidewell heard us, as they are no longer recommending it
either. Shoulder it or deep chamfer it, but get some bulk at the
margins - gary
No ceramic material currently on the market is as strong as cast metal.
None. Not all ceramic on the market currently has the tensile strength
of metal. None. Wolceram is one of the strongest of the ceramic
materials, but taking it to a knife edge finish leaves to little
material and there have been some issues with fracture under load
(flexure). We will not allow anyone in our current scanner beta
testing, for instance, use anything less than a deep chamfer on an all
ceramic unit. I have been using wolceram for about 3 years now, and
it is a great material. But Iíve never sent my lab anything less
than a full chamfer, and most of the time a full shoulder of
1-11/2 mm thickness. The other issues are plain and simple aesthetics.
You handicap your lab man severely with a knife edge finish, as the
only way he can do the case is to overcontour the ceramic, potentially
leading to perio issues. Glidewell in the u.s. for a short time had
the exclusive on wolceram, and advocated anything will fly. They are
also the largest lab in the world. Although the material as greg
mentioned is still listed on the website as being doable with any
finish line, privately they are saying something else - gary