zirconia horseshoe fell and broke

G

grantoz

Well-Known Member
Full Member
Messages
1,983
Reaction score
366
I would be more surprised if it didnt break i think you should do a course and stop giving zirconia a bad name.
 
P

privityli

Member
Full Member
Messages
14
Reaction score
0
I cant believe nobody has mentioned your zirconia.. what brand is it? Looks generic...?


Orr.. just dont drop it.. haha It only passes the hammer test, not the drop test
 

Attachments

  • IMG_20150914_094908.jpg
    IMG_20150914_094908.jpg
    107.3 KB · Views: 99
  • IMG_20150914_094952.jpg
    IMG_20150914_094952.jpg
    103.3 KB · Views: 88
JKraver

JKraver

Well-Known Member
Full Member
Messages
3,422
Reaction score
451
The joints are very undersized as well, even with out taking a 2d cross section I can assure you its not in spec.

I have hit many singles with a hammer AKA glidewell and thrown small bridges and watched them bounce. I just tried dropping full arch hybrid from 4 feet onto concrete that had HUGE joints and well it fractured all to hell!! hahhaahahhaahah. Go figure, I just wished I filmed it as my staff thought it was a real case in production and that I went nuts. Boy I laughed my ass off

Sorry your bridge broke beef those joints up

I bet you could hear the silence as the maniacal laugh permeates the lab.
 
Affinity

Affinity

Well-Known Member
Donator
Full Member
Messages
6,918
Reaction score
1,062
Ive never heard of upcera zirconia.. maybe its just the same as the other rebranded zirconia pucks or maybe its crap.. it looks like youre trying to do hi end implant work, *giroform model, why not use a zirkonzahn prettau or something with a track record for a roundhouse implant bridge? I mean, it will cost you far more to mill this 2-3x in cheap zr.. but the connectors look like the main issue here. This is the biggest advantage to zr bridgework..thick connectors and no hitting black metal when you cut into them.. just leave them as thick as possible..
 
JKraver

JKraver

Well-Known Member
Full Member
Messages
3,422
Reaction score
451
Ive never heard of upcera zirconia.. maybe its just the same as the other rebranded zirconia pucks or maybe its crap.. it looks like youre trying to do hi end implant work, *giroform model, why not use a zirkonzahn prettau or something with a track record for a roundhouse implant bridge? I mean, it will cost you far more to mill this 2-3x in cheap zr.. but the connectors look like the main issue here. This is the biggest advantage to zr bridgework..thick connectors and no hitting black metal when you cut into them.. just leave them as thick as possible..
I am pretty sure he is in Greece that may be why the Zir is a weird brand.
 
JKraver

JKraver

Well-Known Member
Full Member
Messages
3,422
Reaction score
451
ya... thought I saw a phi and a pi then looked again. not greek.
 
Affinity

Affinity

Well-Known Member
Donator
Full Member
Messages
6,918
Reaction score
1,062
Ok, he may be in ukraine, but that is either chinese or japanese on the disk.. My uneducated guess would be japanese by the looks of the characters... If its FDA approved, wheres the identceram..?

Not pointing fingers at your zirconia.. but maybe youll get better results with a pricier disk.. and thicker connectors...?
 
Affinity

Affinity

Well-Known Member
Donator
Full Member
Messages
6,918
Reaction score
1,062
oh man, my uneducated guess was wrong, a quick 'upcera zirconia' search yielded "upcera shenzen" .. Probly use ground dog and children bones for filler.. just sayin..
 
lcmlabforum

lcmlabforum

Well-Known Member
Full Member
Messages
1,476
Reaction score
160
I happen to read Chinese and will tell you it is Simplified Chinese (typically meaning Mainland) and ShenZen would be in the PRC.
On another note, maybe that is a good test for big cases then - everyone try to drop it and see if it cracks before it passes QC . . .
:p
LCM
 
lcmlabforum

lcmlabforum

Well-Known Member
Full Member
Messages
1,476
Reaction score
160
From what is written, it seems like this is a high translucency version blank, and 'all natural' . . .
Maybe my translation is not that hot . . .
LCM
 
idusdental

idusdental

Member
Full Member
Messages
14
Reaction score
0
I happen to read Chinese and will tell you it is Simplified Chinese (typically meaning Mainland) and ShenZen would be in the PRC.
On another note, maybe that is a good test for big cases then - everyone try to drop it and see if it cracks before it passes QC . . .
:p
LCM
[Bump] Howdy? =)
 
Techy

Techy

Active Member
Full Member
Messages
183
Reaction score
8
I would almost bet any zirconia (any brand, 600-1500mpa) thick or not,,,would have a similar result when dropped.
Its Zirconia!
Sorry this happened, but it will happen.
 
R

richgreen

Member
Full Member
Messages
18
Reaction score
0
In your photo you show a flat full arch sintering connector. Was this the actual connector? If so it is possible that stresses were created during sinter firing because although the connector is not thick, it is really wide. It may be helpful to note that while zirconia shrinks during sintering, it is because the grains agglomerate and close the voids between grains. Then when we heat up to 1500C, or there about, the zirconia expands. Then when we cool it to room temp and it shrinks again. lots of potential stress build up. Even if total shrinkage is 1% from hot to room temp, any bridge could be 100mm around the arch and 40mm across. That's relates to 1mm of movement around the arch and .4 across.
The shrinking of that lingual puck of zirconia, because it would cool slower, could place stress at the thinnest points. Not enough to fracture the bridge during firing but with the addition of energy (the bridge striking the concrete) could trigger a stress release that shows up as breakage. Just food for thought. Oh, and yeah that really sucks.
 

Similar threads

H
Replies
19
Views
986
GG - J
GG - J
S
Replies
17
Views
1K
technician
technician
GhostFake
Replies
14
Views
356
Car 54
Car 54
Top Bottom