Hydrocolloid Problems

[CShof]

I am now just a few weeks away from opening my lab. Up until this point someone else has always handled the hydrocolloid and I've run into a problem I need some help with. Bought a used CMP hydrocolloid machine.

http://www.cmpindustry.com/DuplicatorsSalesSheet 05.pdf It's the one pictured on the left.

I found a good deal for hydrocolloid online and I'm wondering if I'm going to regret it. Its called dupli-rite. I chopped it up, poured it in and started the melt down cycle. It melted and cooled perfectly. I poured a little out and it was nice solid blue. Next day the blades slide out of place and the machine stops mixing. It wasn't more than 15 minutes as I was checking it periodically. Figured out the people I bought the machine from put the coupler between the motor and the blades in upside down, I fixed the problem and have had no problems since. But now I pour a little out and it looks more like its clear with blue specs in it. Should I remelt?

Here is my real problem. I pour hydrocolloid in a duplicating flask to make a duplicate. It solidifies just fine and I pull out the model, no problems. Now I go to pour a new the duplicate and once again everything seems fine. I give it plenty of time to cure(overnight once) but then when I go to pull it out the stone is still semi wet. Its like the hydrocolloid is giving water to the stone and not letting it cure. Is it my hyrdocolloid? Do I need to remelt? What else should I do?

 

[CloudPeakDL]

Are you cooling the flask after you pour? You may need a cooling tray.
You need to remove the cast as soon as it's set up 20 -30 mins, letting it set longer will allow the moisture to seep in and etch the cast.

 

[Denturetech]

Every time I have ever used Hydrocolloid the cast allways comes out alittle wet. I dont see what the problem is. Hydrocolloid has water in it. Maybe dupe with Alginate if you are affraid of a wet model.

 

[CShof]

The model isnt just wet, its mushy wet and will not fully harden. The entire outer layer that touches the hydrocolloid will just wipe away when you touch it due to this mushy wetness. It leaves all models completely useless with no detail what so ever. You know how when you get a repair and pour a model but you didn't get all the denture adhesive out? Right in that spot where that adhesive is, the model doesn't cure properly and you're left with this mushy porous area on your model. That's what the entire model is like.

With the weather I have ice cold water. I've tried water cooling only, bench cooling only and bench cooling followed by water cooling. All three yield the same results. I've tried pulling out the model as soon as it sets, I've given it over an hour and I've tried leaving it overnight. Still the same results. I know this isn't rocket science and I've been pouring duplicates for years with no problems, this can't be this difficult.

I remelted and the mixture still looks like its clear with blue splotches instead of a pure blue color. I've poured another model and I am currently waiting for it to set to see if the remelt had any effect.

 

[Denturetech]

What stone are u using?Maybe the stone is old. Maybe its the stone and Dup dont mesh well for some reason.Change to Polyflex Dup all ways have good results from that.

 

[CloudPeakDL]

I would call the company that makes your material, they should have someone who can troubleshoot for you and let you know if the spots are normal. It sounds like a chemical reaction between the dup material and stone, Borax will do that but can't imagine you have borax in your dup material. Are you rinsing the mold before you pour the stone?

 

[CShof]

Remelt had no effect. I was using Modern Materials labstone on the first several tries. Now I'm using cheaper plaster until I figure out whats going on. Both do the same thing. The stone and plaster both set up well in outside of the hydrocolloid, it has to be the dup material. In the past we've always used Polyflex, that'll teach me for trying something new.

As though I haven't already learned my lesson, has anyone tried the Echo duplicating material from Fricke? It looks like a fairly good deal at $60 2/gal.
Fricke Dental -

 

[Clear Precision Dental]

I also make sure to lightly blow air in the hydrocolloid before pouring the duplicate. This helps identify and remove any of those little tags or flaps that sometime remain behind after removing the original cast. Alginate can be slightly wet when pouring and the water displaces, but it is not the same with reversible hydrocolloid. Residual water jacks with the water/powder ratio with reversible hydrocolloid and creates that slime/ chalky layer. Try a little air!

 

[CShof]

Thanks for the advice. I tried blowing air to remove water. On my last attempt I blew it out then let it sit for another 15 minutes to dry out some more just in case. I feel like I've tried everything. I've ordered some Polyflex, that should reveal whether its the duplicating material or operator malfunction.

 

[CShof]

Problem solved, thank you Polyflex!

 

[TheLabGuy]

Now I'm curious what's in that previous hydrocolloid material that it would dissolve a gypsum product? Any idea?

 

[JohnWilson]

Was this material specific for gypsom products or made for refractory material? Sometimes the two do not share the same properties.

 

[DDDental]

Definitely so. There are two types of reverse hydrocoloids, water based and oil based. The second one is used for ethyl silica investments vitalium like investments for refractory models. They CAN NOT be used for gypsum product. Stay with Polyflex and you should be fine. Also try GC DupliCoLoid, works perfect for me.

 

[sth]

tried alum solution ?

when i used to pour dupes in agar - 10 years back, we filled them with a 2% solution of alum,let thm stand for 2 minutes,poured the alum sol back into it's container ready for re-use,flushed them out under the cold tap and poured them up.
they would only get a chalky surface if we let them stand too long after initial set.
just my 2% worth ...

 

[kcdt]

when i used to pour dupes in agar - 10 years back, we filled them with a 2% solution of alum,let thm stand for 2 minutes,poured the alum sol back into it's container ready for re-use,flushed them out under the cold tap and poured them up.
they would only get a chalky surface if we let them stand too long after initial set.
just my 2% worth ...

Potasium sulfate 2% fixing solution.

 

[Brian]

The problem has been solved, however thought I would share what I use..

I have been using the WiroGel from Bego... Melt @ 205f and pour @ 130f...

I have a pyrex dish I set the flask in and into the deep sink with a steady cold stream of water... The model comes out so nice I actually write duplicate on the model to keep the two from getting confused..

I have used Dentsply and Dupli Coe and always got a little frayed at the insical edge of the teeth..

Just chiming in...

 

[ManolisChalkias]

I have the same problem with Premeco line of Merz Dentals. I will try Polyflex or Wirogel. Thank you guys...

 

[Doris A]

I've used both Polyflex and Wirogel. I think Wirogel is better.

 

[Alan JDL]

I've used both Polyflex and Wirogel. I think Wirogel is better.

Same, we use wirogel every day with excellent results.

 

[Wade Bognuda]

If you ever switch to silicone you'll never go back. A little pricey, but worth it. JMHO.