K
king v12
New Member
- Messages
- 1
- Reaction score
- 0
after firing lots of cracks on 8to 12 unit bridges
Mainly due to greater shrinkage than 'conventional' ceramics, which leads to tears. But not to cracks.d.sign in general tends to be a bit of a finicky porcelain
That I do on bigger cases. Easier to control volume and placement of the different layers. You can even stain onto the first dentin layer to characterize an incisal edge, for example.Layered firing is a must from what I have seen,
Very true. I have fired d.Sign countless times on full arch bridges. As long as the framework is 'clean and solid', ie no bubbles coming up from underneath, you can fire d.Sign several times.With a large bridge I am sure multiple firings are standard.
Good technique. What I do is what you mention below. At the same time, I brush glazing liquid over the opaqued frame and then sprinkle shoulder powder on it. Or dip the frame into the powder... ;-) So, I do my normal opaque firings and then I do the above mentioned.I sprinkle shoulder power on the last opaque coat before firing.
Most of the time, I use a darker deep dentin, which helps the esthetics of the final bridge. Under pontics, I sometimes mix MM light into the DD, to get a bonier appearance.I use shoulder powder to fill under pontics and in the interproximals. This helps keep the porcelain from pulling so much when layering the dentine.
Try glaze cycle under vacuum, release @ 25° below high tempI still use d.Sign porcelain, even on full arges. And even on CoCr. frames. But d.Sign 84 is a Pd base alloy, which are not my favorite alloys to deal with...
Mainly due to greater shrinkage than 'conventional' ceramics, which leads to tears. But not to cracks.
That I do on bigger cases. Easier to control volume and placement of the different layers. You can even stain onto the first dentin layer to characterize an incisal edge, for example.
Very true. I have fired d.Sign countless times on full arch bridges. As long as the framework is 'clean and solid', ie no bubbles coming up from underneath, you can fire d.Sign several times.
Good technique. What I do is what you mention below. At the same time, I brush glazing liquid over the opaqued frame and then sprinkle shoulder powder on it. Or dip the frame into the powder... ;-) So, I do my normal opaque firings and then I do the above mentioned.
Most of the time, I use a darker deep dentin, which helps the esthetics of the final bridge. Under pontics, I sometimes mix MM light into the DD, to get a bonier appearance.
To circle back to the OP question. I don't have an answer to your issue. But considering PD base alloy, I have a strong feeling of a framework with issues. Do you slow cool? Your cracks may be a sign of bubbles coming up, too.