Dry Mouth impressions

denturist-student

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I have a Dr who uses hydrocast, and before he sends it to me he does a microseal wash inside the hydrocast.
Thanks. I have only seen it used on a Turbyfill video....He used it as a preliminary impression and then cut it back and used hydrocast over top of it. He also takes his impressions using preliminary casts on a reline jig so as not to loose the occlusion. Seems like a good idea to me. I did this once and the impressions came out outstandingly accurate but I subsitituted Tempo for hydrocast.
 
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I have a Dr who uses hydrocast, and before he sends it to me he does a microseal wash inside the hydrocast.
Is there any sort of precautions you use for hydrocast? I would likely use wonderfill as a base and do an upright cast much like boxing and beading.
 
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You are making way too much work for yourself. Seriously. You shouldn't have to go through all of this misery dude. PVS is the worst impression material for final impressions on gingival tissue. It's great for dentition but for tissue duplication you're better off with a polyether material like Impregum F. In my 25 years of making dentures, PVS has always resulted in poor retention. It folds over, traps air. Many others will disaggree, but for completely edentulous mucosal duplication PVS is pure garbage. My suggestion is to chuck the current denture and start over. Use the previous denture to take the final in Impregum, pour up, trim and mount without seperating the denture from the casting. Make an occlusal matrix of the old denture using Zeta putty, and set up on that. Try in... yadda yadda... flask it.... pack it.... IMPORTANT: Let case stand for at least a half hour in the clamp before processing. Bench cool... then you know what to do after that. It's okay to chuck a case and start over once in a while if it's not working out. If you still have a fit issue. Don't be afraid to let it settle in for at least 20 minutes. It it still drops, then use your Tokyamo. THIN apllicaton. Read the directions. AGAIN... THIN APPLICATION. If you get folding of the material then you most likely have relieved the denture or bored it out too much and you're short on resin. THIN the application. Works every time.
Thanks for the advise...I use both Tokuyama products routinely. The tokuyama soft medium for lower relines direct and the hard for upper relines. But you cannot use it on people with undercuts. I had one clamp on and it was really difficult to get it out. But the man is satisfied today still uses that relined denture quite well.
 
Doris A

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Is there any sort of precautions you use for hydrocast? I would likely use wonderfill as a base and do an upright cast much like boxing and beading.
That's exactly how you want to pour the model. The only precaution is you need to make sure before the model is poured that you keep your impression right side up, don't let the borders sit on the counter, that will distort the hydrocast.
 
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Thanks. I have only seen it used on a Turbyfill video....He used it as a preliminary impression and then cut it back and used hydrocast over top of it. He also takes his impressions using preliminary casts on a reline jig so as not to loose the occlusion. Seems like a good idea to me. I did this once and the impressions came out outstandingly accurate but I subsitituted Tempo for hydrocast.
Turbyfill only uses microseal on the lower ridge to act as a stop because hydrocast flows for 24 hours.
And yes you should use a reline jig for the preliminary impression. With all of the problems you're having with this patient I think hydrocast will be your best option, let her wear it for a few days and refresh it as needed.
 
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Turbyfill only uses microseal on the lower ridge to act as a stop because hydrocast flows for 24 hours.
And yes you should use a reline jig for the preliminary impression. With all of the problems you're having with this patient I think hydrocast will be your best option, let her wear it for a few days and refresh it as needed.
Thanks a lot for your advise and I will let you know how things turn out.
 
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Thanks for the advise...I use both Tokuyama products routinely. The tokuyama soft medium for lower relines direct and the hard for upper relines. But you cannot use it on people with undercuts. I had one clamp on and it was really difficult to get it out. But the man is satisfied today still uses that relined denture quite well.

Actually you can use it with undercuts (the trick is to remove the denture at the right moment while it's still slightly flexible and soft). It's not a problem, including partials. It helps if one follows directions.
 
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Actually you can use it with undercuts (the trick is to remove the denture at the right moment while it's still slightly flexible and soft). It's not a problem, including partials. It helps if one follows directions.
Yes I have had some experience with undercuts on upper arch with Tokoyama. But in that case I waited too long. Poor fellow yelped when I removed it as it slid over the bulbous tuberosities....I then cut it back a bit so he could put it in and out without too much problem...I felt really badly. That was about 6 months ago and I recenlty heard he was doing quite well with them now. .....take care and keep well....
 
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Firstly, I would like to see the pattern when you disclose the fit of the intaglio with something like PIP,
or even the GC Fit Checker.
My suspicion is the post dam is too deep at the midline where there is less displaceable soft tissue.
Recheck after each adjustment until you have even layer every where when the denture is static.
Then I will like to examine the pattern of the fit check when you have the patient perform all the
border molding movements.
Cheers!
LCM
 
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Firstly, I would like to see the pattern when you disclose the fit of the intaglio with something like PIP,
or even the GC Fit Checker.
My suspicion is the post dam is too deep at the midline where there is less displaceable soft tissue.
Recheck after each adjustment until you have even layer every where when the denture is static.
Then I will like to examine the pattern of the fit check when you have the patient perform all the
border molding movements.
Cheers!
LCM
Thanks for the advise. I recall during the final impressions that the lady said it was a bit loose but I had suction. Suction is there when impression is taken but looses it after it is withdrawn and reinserted. It was loose post processing. Then I tried a Tempo tc for a functional. She did not like the taste and went back to old dentures. Then I tried again with pvs and got suction consistently. But I am thinking it is a flow problem because it is bunching up in the palate and on the crests of the upper. Too thick there. I am going back and trying with extra light wash after bordermolding with heavy or regular and when holes are drilled in the palate to relieve pressure. Usually I will use a light body for wash and I think ti just needs an extra light. Problem being mobile I need to take it back to lab every time to regrind it all out. My little rotary nail file is only good for minor adjustments. When it bunches up on the palate it will never really fit afterward because bite is compromised and the front teeth are pushed forward a bit..... So I am either going back to extra light body or trying a Hydrocast functional. Clinical problem for sure. I like to use custom trays for final impressions. Some use bite rims with a stable light cured baseplate but I am not sure that works all the time..I will try that if I can and only if monoplane occlusion is prescribed. Anyways thanks again for the advise.....take care and keep well...I agree with you that pip should establish the fit quite well...perhaps I am just getting frustrated with it.
 
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Problem solved. Drilled three relief holes in the palate near the front. Now stays in place after processing. Must have been a slight amount of tissue rebound. That is why I usually do not let the patient bite on the appliance when a reline is taking place. Too much pressure builds up and slightly distorts the tissue.Also got rid of the lower quality pvs and use only Virtual....which seems to flow much better. Also a closed mouth impression appears to work much better....Thanks to all for the input.
 
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Problem solved. Drilled three relief holes in the palate near the front. Now stays in place after processing. Must have been a slight amount of tissue rebound. That is why I usually do not let the patient bite on the appliance when a reline is taking place. Too much pressure builds up and slightly distorts the tissue.Also got rid of the lower quality pvs and use only Virtual....which seems to flow much better. Also a closed mouth impression appears to work much better....Thanks to all for the input.
Thanks for the update. Hydraulic pressure buildup can cause al sorts of oddness. But never would have thought of it here. Interesting thoughts happen now.

Will you be using relief holes for all future cases, or just when it goes pear shaped?
 
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