Troubleshooting RPD Framework

[Flipperlady]

I have a framework the dentist sent back for redo becuase he couldn't get left side to seat He didn't adjust at all just said it wouldn't fit mouth (fit model well.)
Missing 6-11, interproximal rests between bi's. I really hate interproximal rests BTW. I adjusted quite a bit on clasps and rest areas and got partial down 99%. I've seen this before and of the opinion the teeth move just a bit between appointments and this kind of design is not forgiving at all. I'm tempted to tell the doc to let the pt. wear framework home for a day or two and see if it seats. The reason I squirming to remake is that this usually happens again between appointments.
Any comments or advice?

Thanks!

 

[rkm rdt]

If it fit the model well before, then why did you have to adjust it to seat 99%?

 

[Flipperlady]

Fit original model well, adjusted to new model. (Actually there were two new models

 

[araucaria]

Back to the beginninng - Impression.
If there was finger pressure over perforations at the premolar zone - it's possible that upon withdrawal fron the mouth the impression material pulled away from the tray slightly due to lack of retention to the tray. This leads to a model where the occlusal surfaces in this zone are lower/away from where they should be. The deformity of the teeth on the model can be very small indeed. The result is a frame that sits prematurely at this point and will rock or just not settle at all. Wherever a non perforated tray is used there can be areas of deformation that can't be seen. The areas of deformation imo occur more frequently in the incisor region, accross rugae, or at last molar zones. A big cause of deformation is removal of the impression prematurely from the mouth before full and proper setting reaction - this can be anywhere along the occlusion or palatal vault. All can look perfect - it can be a stressful journey to the solution.
Investigate Imp', Modelmaking, model prep for defects/damage.

 

[CYNOSURER]

I've always said: We can sometimes tell if we have a bad model but, we can never tell if we have a good one.

 

[Flipperlady]

Araucaria,

I think you are right. My problem is that my job is to try and help without making anyone look bad including myself I adjusted and took back yesterday. The office just called and said it fit well and to come pick it up.
I'm going to buy the doc a can of that green indicating spray ;-)
I wouldn't panic so much if I made my own frameworks, but I'm at the mercy of dentist and outsource lab (which is all American and registered in Texas BTW and if something goes wrong even though I just stuffed a box and mailed it, I look bad on either side.....


Michelle

 

[CYNOSURER]

So after adjusting to fit new model did you put it back on the original model to see where the problem was. And did you inspect that area under magnification for indications of abuse (chipped, scrapped, etc) by the partial lab?

 

[Flipperlady]

So after adjusting to fit new model did you put it back on the original model to see where the problem was. And did you inspect that area under magnification for indications of abuse (chipped, scrapped, etc) by the partial lab?

Hey Tim,

It's a possibility as I noticed the clasps have been a little too tight lately. I looked it over and saw one suspicious spot on second molar
All in all they do a pretty good job.I'll check the model better when I get it back on Monday, but seems it's going to work out so I'm happy for now.

Michelle

 

[araucaria]

I'm at the mercy of dentist and outsource lab and if something goes wrong (even though I just stuffed a box and mailed it),I look bad on either side.....

Michelle

Been there, got the T-shirt. Horrible being "pig-in-the-middle"
Gotta be real tough on the examination of the impression you receive. Be like CSI looking for clues. If all looks ok go ahead and make 2stage model with die stone quality model material. If you're paying good money for the frame - insist on silicone duplication and get a stone duplicate from it too for after-checks. Shouldn't have problems.
Over tightening of some clasps can cause seating problems. Too many clasps can cause seating problems. From what you've stated before it would seem most likely the difficulty started with the impression, however the surgeon will not deliberately let a defective impression leave the clinic for fabrication to begin. Any error is an "honest" error and the "Team" should communicate and work together to identify the root cause. Hope this may help, please let us know how the case develops and if a solution is found.