In-Line porcelain to metal bonding issues......HELP!!

[jackjabbour]

Ok so here is the situation, I've been a Ceramco 3 user for many years and recently switched to Ivoclar's In-Line porcelain. With my ceramco 3, I rarely had any issues with it. It was very easy to handle, decent color, etc.....BUT I have recently switched over to In-Line porcelain and here we go with the problems. The problem I am having is with the opaque bonding to my semi-precious alloy and precious alloy. At first I was getting bubbles like crazy....I talked with technical and a few labs I knew were using it and they gave me a few suggestions, and the bubbling was gone, but now I am having problems with the porcelain shearing off at the time of seating the crown. The docs are sending me pics of the crowns with at least half of the porcelain and opaque completely removed off of the crown...They are saying that during the seating of the crown, when the patient bites down the porcelain just shears right off the crown. The opaque and porcelain is coming right off the crown. The alloy is a hi palladium based alloy, even my hi-noble is a hi pd content due to the cost of it. I am using ivoclar's metals as well and it is definitely in the correct CTE range. I am using for SP-d-sign 59, and for Precious- Evolution lite.

So I am 99% sure that Im gonna change porcelains unless one of you kind people can help me out with this issue. Any help would be greatly appreciated, and many thanks to you if you reply.

Peace!

jack

 

[Gru]

Jack, seems very odd. I use InLine and have zero problems with it. Are you following the surface preparation/oxidation guidelines enclosed with the alloy exactly? The CTE of dsign 59 is on the high end but should still work. If so, is your porc. oven accurately calibrated? Firing sequences exactly correct? Did you note the odd little note in the InLine book on pg7 "cool to 800C" for the dsign 59? Are you stacking excessive thickness? It doesn't forgive quite as well as ceramco, but isn't too picky. Your info sounds like opaque debonding, and as far as I know that's usually CTE or surface prep/oxidation, or temps. Best of luck. Please let us know how it goes.

 

[lifelikedental]

I had a similar problem in the past.


I used Jensen Creation porcelain with Porson lite semi precious alloy from Dentsply for a long time with no problem.
They share the same CTE range of 14.1~14.3

When I tried Inline porcelain, it would literally sheer off of metal at insertion like u mentioned. Not even opaque was sticking to it.

I later found out that CTE of Inline was on the low side.
12.6~13.2

 

[CatamountRob]

Have you double checked the oxidation instructions for the alloys to make sure that you are following them exactly? Some alloys also require sandblasting after oxidation (W2 for example) to control the amount of oxide. If an alloy is over oxididized and the porcelain shears off all the way to the metal, you will likely see the oxide layer stuck to the ceramic piece that came off. If its under oxidized, there probably won't be any oxide on the ceramic and the metal where it came off will look clean. If it isn't a CTE issue, it is most likely an oxidation issue. I've been through this when we changed alloys and neglected to change the oxidation programs in the furnaces.

 

[Gru]

BTW the instructions with the alloys you use say to blast @ 5.2 bars. Pretty high pressure, but...

 

[CatamountRob]

Evolution Lite:
OXIDATION
Blast surface with 50-100 micron AL O at max. 5.2 bar/75 psi pressure before oxidation.
Subsequently, clean with ultrasonic or steam. Place the object on the firing tray and provide adequate support. Place the tray in a porcelain furnace set at a low temperature of 650C/1200F and increase the furnace temperature to 950C/1740F without vacuum with 5 min. hold time at top temperature.

IPS d.sign 59:
OXIDATION
Blast surface with 50-100 micron AL O at max. 5.2 bar/75 psi pressure before oxidation.
Subsequently, clean with ultrasonic or steam. Place the object on the firing tray and provide ade- quate support. Place the tray in a porcelain furnace set at a low temperature of 650C/1200F and increase the furnace temperature to 1010C/1850F without vacuum with 10 min. hold time at top temperature.

 

[jackjabbour]

WOW! thank you all for responding!!

Ok the only thing I haven't done is check and calibrate my ovens. I am following the correct firing programs for each alloy, but one thing I do differntly is sandblast the oxide layer off after oxidizing because when my alloy would come out of the oven, it looked like a piece of charcoal??? So when I switched to Inline and started having bubbles, I assumed the oxide layer was too thick which was causing the bubbles so I started to sandblast after oxide firing and bubbles were gone......but now the porcelain and opaque are coming off???

I guess Im going to have to calibrate all my ovens. What do you think about the dark oxide layer tho?? should I continue to sandblast it off, or maybe I should wait to see what it looks like after I calibrate my oven? If I calibrate and the alloy doesn't seem to have as dark as an oxide layer as it did before, I will not sandblast it off, since thats what the alloy manufacturer recommends anyway!

So thanks for your help guys, its really appreciated! BEST of luck to all of you!!

jack

 

[CatamountRob]

Neither of the alloys you mentioned is supposed to be sandblasted after oxidation. You aren't getting a chemical bond because you don't have any oxide left.

 

[Gru]

CatamountRob is right. You need some oxidation to get a bond. If the porcelain that is popping off does not have oxide on the metal side of the opaque (still attached to the porcelain that popped off) then you do not have too much oxide.

 

[charles007]

Jack, your problem is solved, thanks to Rob....Basic Porcelain 101 class...

By the way Jack, Rob just took you to school :wave:

 

[charles007]

Another frequent problem with opaques, drying paste opaque to fast, which blistering appears, using to high of a low temp, and over firing opaque to a glazed appearence, then losing your bond..

 

[Toast]

All good advise. I'm using inline with ivoclar's Spartan alloy with no issues except for dark oxide layer due to the Cu content. I fount this tool in Ivoclar's website thought it might help. The info tab has some good links for proper technique and trouble shooting.
Peace of Mind Configurator

 

[jackjabbour]

thanks!!

 

[bonded]

maybe the oven need to be clean with carbon block ???

 

[charles007]

maybe the oven need to be clean with carbon block ???

Welcome aboard bonded

Carbon blocks are not used anymore !! that's old school Newbie... and problem was solved...... older thread

 

[Hary]

4 things 1 sandblast 2 ultrasonic and not steam 3 oxidation 4 hot plate for the opac
you will minimise most of your problem.

 

[Polarmolar]

Is there a reason you do not hot steam? I have told that's usually the way to go lately but was never really given a good reason.

 

[Hary]

Is there a reason you do not hot steam? I have told that's usually the way to go lately but was never really given a good reason.

Hi, the reason is that in the steamer there are some impurity build up on the walls of your steamer from inside and withe hi presure from the nosel your aplying on your crown some onwanted impurity that can cause pour oxydation surface.

 

[Edy]

4 things 1 sandblast 2 ultrasonic and not steam 3 oxidation 4 hot plate for the opac
you will minimise most of your problem.

Hi , let's see, I am using inline for 7 months now, I use sandblast then steam , had no problems so far , only sometimes I get a yellowish color on the first opaque ,it's like some areas with yellow and some are ok on the same crown .
The question I wanted to ask u is why do u think I am having the yellowish color ? Maybe because I over heat the metal while I melt it in the casting process? Or because I never use an oxidation before opaques ?
Oh and what u ment by a hot plate. Why does that helps with anything ? And in the ultrasonic what u put if u don't steam ? Just water?

Thanks

Edy

 

[NathanNever]

I do not use inline, but I can give my word of advice, maybe granted. I do my casting in an inert atmosphere, treated with metal cutters tungsten carbide cutting fine cross. 50 microns Al2O3 abrasive blasting, steam ,vacuum degassing 950C 5 minutes, re-sanding, steam, oxidation in air 950. If I needed, I do an oxide reduction. Logically, if the opaque fired at 980C, the whole process gets up to 30C.