Need Tips- Emax Contacts

[charles007]

I'm having problems getting good contacts with emax press, and even more so with multi unit crowns. Most of the time the contacts are extremely tight and even tighter with multi units.....
How do you wax to get better contacts, and how do you adjust after pressing ?
I have Accufilm 1 single sided.........Bausch Arti-Fol Metallic 12 micron and Almore Shimstock Foil 8 micron.........also use Renferts expensive Bi-V-Pins, metal sleeves.

 

[sixonice]

I'm having problems getting good contacts with emax press, and even more so with multi unit crowns. Most of the time the contacts are extremely tight and even tighter with multi units.....
How do you wax to get better contacts, and how do you adjust after pressing ?
I have Accufilm 1 single sided.........Bausch Arti-Fol Metallic 12 micron and Almore Shimstock Foil 8 micron.........also use Renferts expensive Bi-V-Pins, metal sleeves.

Here is the absolute best e.max adjusting/finishing/adjusting contacts rotary's on the planet. Using these Diagen wheels will make your life SO much easier for making adjustments or loosening a contact. XPdent - Sintered Diamond Diagens
What gets me is the fact that your not happy with the contacts after pressing? What you see (and feel and measure) in wax is what you get in lithium disilicate. It won't matter if they are a bit tight after pressing if you get yourself a set of the Diagen's. Yes, they are more expensive....but they should be because they work better than anything else by leaps and bounds. Just will have to trust me, I am sure other folks will back me on these - and they last a long time.

 

[charles007]

Thanks Sixonice, will you post the rotary's you use for your contacts, and your favorites for general emax -porcelain contouring.
Even with the Bi V pins, I'm getting movement in the waxing step, then catching hell in the finishing and layering- adjusting of contacts.....
My occlusion needs practically no adjustments.
Thanks

 

[rkm rdt]

Check your contacts on a solid model and with a microscope.

 

[TheLabGuy]

When it comes to E.max contacts, I don't do them like full cast gold. Usually with gold you'll add a little extra that way you have a nice contact by the time your done polishing. With e.max, I just wax up normally, nothing extra added before I invest. Then I devest, finish, smooth it up, steam clean and then stain and glaze it. At stain stage I'll take some of my e.max ceram A-0 incisal or A-0 dentin (if it's a dark shade) and add what I need for a contact. Then fire it under the stain cycle, then glaze cycle and use a white wheel to adjust where I want the contact, then a high shine wheel to put the high shine back on. Nothing to it really, it's simple and fast. I'll have to try some of those Sintered Diamonds 'sixonice' is talking about, sounds like they are good to go.

 

[charles007]

Check your contacts on a solid model and with a microscope.

Using a solid model to check my contacts is where my problems start, with only "ONE" of my accounts........other accounts, no problem ever.
I've heard of very lightly scraping the solid pour to insure the contacts are tight in the mouth.
I'm looking to learn how do you grind in contacts, techniques, what to feel for with certain brands of articulating paper etc. Trying to wax like a full gold crown gives me tight contacts. Waxing multi anteriors-post, creates more adjusting.
I don't have the years-"any" experience in making veneers as do many of you have. I'm getting more and more emax cases every week and beginning to hate to see them come into the lab.......

 

[charles007]

55 VIEWS so far, with only 3 Responses........

Maybe Travis should charge us to join this great dental lab forum.........or charge the lurkers a TOLL CHARGE.

 

[Al.]

55 VIEWS so far, with only 3 Responses........

Maybe Travis should charge us to join this great dental lab forum.........or charge the lurkers a TOLL CHARGE.

Hey Charles, Ive read this thread a couple of times but Im working my butt off to be able to be off tomorrow.
I will post my tech Sun night.

 

[charles007]

Thanks Al, I know you and all my buds will chime in when there free.......
Most of us are working 24 hours a day, or at least it seems that way.......Heck, I need to be in the lab right now......

 

[SiKBOY]

I always use solid models to check contacts with every job. Maybe try waxing the contacts just shy of each other, just so that you can see some sunlight come through. If you fit them on the solid model and they still come out tight, you know that the mixing ratio of your liquid to water needs to be adjusted.

Of if they are just shy, fix the contacts up with the glaze when glazing. Its a lot easier to rubber the glaze than grinding emax with the highspeed under irrigation.

 

[2thbob]

One thing you didnt specify...Is the Doctor saying the contacts are a problem, or just not easy for you to handle the product? If theyre good to you but the Doctor says theyre off but good on the model, Id look to bad expansion in youre die-stone, or a miss-match between die and base stone expansions. lly, use the same stone for both, and be strict with the powder/water ratios. The more units, the more pronounced that problem becomes. (pour a full arch with lots of pins with good low expansion die stone, and base it with a higher expansion stone and youll likely get a crack in your die stone.

 

[wwcanoer]

Another thought to add to 2thbob's comment. If it was just the doctor complaining, it could also be poor temporary technique with open contacts. Those adjacent teeth can move pretty quickly in some mouths!

My two cents worth on this Saturday afternoon.

Carol

 

[charles007]

Temps are the problem, I guess......Its only with one doctor, with full arch impressions.

I'm just looking for tips to improve, or maybe change my technique for grinding in contacts for emax and pfms, which I didn't say pfms before...... My emax contacts just creates more work for me than adjusting pfms contacts..........
I use flow stone for the bases, and Talladium's Tuff Rock, a low expansion die stone.....
I started using solid pour models to check contacts with Shimstock 8 mic. Making the contacts so tight the Shimstock will not pull thru at all ! Thats when I started getting more crowns back, to add contacts.
My only solution I can think of, is using the same stone for the bases and changing my technique slightly to be more consistent. Earlier this week I added to the mesial and distal using a solid pour and scraping the model on both MD.
Just looking for consistency to refine my technique....... please be very specific in giving your technique.

Thanks

 

[SiKBOY]

Hey Charles,
I use the working model as just that, Its meant to be worked on and not really for accuracy.
No matter what working model you use, there will always be flex in the pins, base, dies etc so there is no way that you can get accurate contacts unless its a solid model

I always leave my contacts until the last fire (making them shy during my builds) and make sure that the contacts are spot on, looking under a microscope to see if the margins are all closed.

If you are making the contacts so tight that you can't pull any articulating paper through on the working model, its going to be even tighter on a solid model. If your client is complaining that the contacts are open. The fault is on his end. Either his temps are way too big and too tight or something else is going askew.

You can only do what you can do with your models. Anything outside of that is not under your control.

 

[wwcanoer]

Charles,

It sounds like this is a relatively new problem, correct? I had a somewhat similar issue last spring that about drove me nuts! My crowns fit perfectly, contacts and occlusion, on both working and solid models. But once they got to the mouth, the doctor was complaining that the contacts were incredibly tight, and occlusion was way high. In a few cases, that I was able to get the crowns back to look on the models, contacts would be wide open, and he would have taken crowns out of occlusion by probably a good millimeter. Working with the assistants, I finally came to the conclusion that it was bad batch of impression material, because once it was all replaced things were back to normal.

So if this is a new issue, talk to the assistants and find out if something has changed at their end. This could be either impression material, temporary material or even a new assistant, depending on whether assistants in your state can make temporaries.

Carol