JohnWilson
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A great way we found is to fabricate a screw retained denture set-up for the dr. to try in and the patient to approve before proceeding
Just curious,Screw retained to what substructure? Triad?..or do you just do a wax tryin with the uclas and denture teeth in the wax?[/QUOTE]
I have done this technique many times.
After having the master model mounted ...
1) I make a verification jig for our master model out of the uclas/pattern resin that I will be using in a later step. I index the occ with wax for a bite registration on my articulator
2) AFTER the model has been verified and the bite has been double checked I choose the cheapest PMMA denture teeth I can find and do an anatomical set up including any gingival contours that will be replicated when the definitive restoration is fabricated.
3) After approval I make a matrix and remove the wax up from the cast, I then screw on analogs to the UCLA's block out the access hole with putty and make a model out of low expansion die stone. I then flask and boil out the case and eliminate the denture teeth from the flask and pack pattern resin in a cold flask.
3) I devest and remove soft tissue from master model and check for pattern passivity. Once I have the pattern passive (sometimes you may have to section and relute) I make plunge cuts to a uniform reduction of 2.5mm to the entire pattern. This is verified with the matrix I made in step 3.
4) I again recheck the pattern for a passive fit as sometimes when you grind on pattern resin it will heat up and distort if your not careful.
5) Now I take up to .5mm of wax and cover the entire frame prior to investing. This smooths out any rough spots in the resin and allows for an easier burn out of all that plastic as it creates less stress on the mold.
6) Sprue, invest, burnout at a very slow rate staging at least 2 times. Cast and devest. EDIT I forgot to add that you should NOT blast the UCLA interface you should leave the investment there and strip the remaining investment with a chemicle devester,
Now the moment of truth, check to see if you have a frame that is passive. Now this doesn't mean that when you screw both ends of the frame to your master model that it seats It means that when you take one screw any where on the model and screw that down and the frame does not move then you have it passive. If not disk and laser-weld till it is.
Now all of this work you have a perfectly supported frame that is guaranteed to fit in the mouth if the client took the time to verify the jig properly in the first place.
This definitely takes more time than waxing but I like the control I have using the resin instead.
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