BellGlass on Zr?

[Naomi]

Hi All,

I was asked yesterday if one can use BellGlass on a Zr framework. I have no idea what the answer to this might be. My immediate thoughts was what the interface between the two materials will be. Has anyone got any answer here, please?

 

[rkm rdt]

why?

 

[DMC]

You are trying to repair something?

 

[Naomi]

This guy only does plastics and BelleGlass. (This is a guy on the Cape flats...in Africa) He cannot do larger bridges because of the limitations of the material he is working with. He wants to know if he can use a zr framework and pack BelleGlass on it in order to manufacture larger bridges. He does not own a porcelain furnace. I need to advice if this is possible, but dont know myself. I have never heard of anyone using it like that.

 

[TheLabGuy]

I don't see why you can't as it's a long term temporary restoration. I do this with metal frameworks for large implant cases in the treatment phase all the time, making a metal large span, then opaquing and putting composite (sinfony) on it. This way the Dentist can add or take away to the composite easily, while still getting the metal structural support needed. As for definitive, there really isn't any studies with the current materials on the market that I know of for that...especially substituting zirconia for metal as you have described.

 

[paulg100]

i thought for long term, you would normally put retention beads or similar onto the metal frame, for the composite to adhere to.

There are also some bonding agents that are made to paint onto frames to facilitate bonding of other materials, maybe try looking into those.?

 

[user name]

It might be tricky, but I bet *** could design retention into the surface.

 

[paulg100]

OK coincidentally i just received this new book today:

http://www.quintpub.com/display_detail.php3?psku=J0622

go buy it, theres an article in there that shows how to do what your asking using aluminium oxide as a retention medium

Oh and a load of other superb articles in there as well, well worth the purchase.

 

[rkm rdt]

Why not full contour zirconia?

 

[sixonice]

ive seen some larger zirconia restorations with resin built only in the gingival portion of the bridge, obviously after porcelain application. they used the gc gradia material and it looked very nice. so basically, he had a zirconia frame, which he layered with e.max ceram, then used the gradia for the tissue areas that needed to be restored as well. as far as i know, the case is still working fine, but as another member mentioned, i couldn't except it any more than a nicer, long term temporary.

 

[trianglej]

I had worked with Belleglass on metal in the past, We would first have to put a tin oxide layer on the finished metal framework, then goes on the silane prep solution, followed by the opaque layer-light frozen prior to build up of composite resin, layered in stages with light cure(also known as the "green stage"). the tricky part would be the heat cure under pressure( the temps are not as high as a porcelain bake, but you would be subjecting the zirconia frame to a thermal stress change) . I don't see how you could get the opaque layer to chemically bond to a zirconia framework, it would all have to be dependent on mechanical retention like previously suggested with beads or mesh design.

 

[Naomi]

Thanks for all the info guys! I appreciate! I will provide him with a zr coping in order for him to do some testing himself. Seems like it's going to work out after all.

Paul, thanks for the tip about the book, I have ordered it! Cannot wait for it to arrive.

 

[paulg100]

NP, the quality of the photography and content in those QDT journals is awesome, ill bet you end up ordering some others once you have the 2011 edition

 

[Mark Jackson]

The only way that I know of to get a reliable bond of resin to zirconia is with an intermediate bonder such as Rocatec. Mechanical retention is a good idea as well, but that wont prevent percolation.

Milled alumina is etchable however, so you might want to think about that, FWIW

 

[trianglej]

Please keep us updated on how that works out!

 

[Naomi]

I dropped off a sample zr coping at this guy today. He said that according to his research, he has to cut mechanical retention into the coping. Just hope he stays away from the diamond disk!

Mark, i agree that Rocatec is probably best to ensure a good bond, but the unfortunate truth is that these guys uses minimum equipment. Chances are that he will cut mechanical retention into the zr coping, some way or another, and just put the Belleglass straight onto that. I dont really agree with stuff like this, but there is not that much you can do about it. Our market is very price sensitive and if that is what this guy can sell to his dentists, what can you say?

He promised to keep me posted on his experiment. Will share any info as soon as i receive it!

 

[thewhitelab]

The only other way possibly, is to ask the milling centre to line the zirconia for him it would then be possible to etch?