Thin , Faint white line in acrylic

[kimba]

Hi All,
had my trainee removable tech bring me a case they processed with 2 thin white lines in the acrylic. Near the palatal periphery on each side of a horse shoe style single central denture.
Its very faint, but there.
Any ideas
Thanks in advance. Sorry no photo as I had to get it fixed and out

 

[Sda36]

Hi All,
had my trainee removable tech bring me a case they processed with 2 thin white lines in the acrylic. Near the palatal periphery on each side of a horse shoe style single central denture.
Its very faint, but there.
Any ideas
Thanks in advance. Sorry no photo as I had to get it fixed and out

Perhaps too much separator used that migrated to that area under pressure and got incorporated?

 

[kimba]

Thanks Sda36,
I thought of that , it makes sense, but it doesnt trim out or seem like the acrylic was not bonded properly. I wondred whether ot was too dry when final packing?

 

[Doris A]

Thanks Sda36,
I thought of that , it makes sense, but it doesnt trim out or seem like the acrylic was not bonded properly. I wondred whether ot was too dry when final packing?

My first thought was separator too. But since you eliminated that, I think you figured it out. The last bit of acrylic added during trial packing was probably a little too dry on the edge and resulted in the lines.

 

[kimba]

Thanks for your reply Doris,
The lines where not quite onthe edge of the denture , about 2 -3 mm up from the foodline. This is why i put it out there, I am unsure if it was seporator or dry acylic. as neither quite makes sense . I think the line was right where some flasking stone overlapped the waxup. Does this make you change your opinion?

 

[JMN]

Thanks for your reply Doris,
The lines where not quite onthe edge of the denture , about 2 -3 mm up from the foodline. This is why i put it out there, I am unsure if it was seporator or dry acylic. as neither quite makes sense . I think the line was right where some flasking stone overlapped the waxup. Does this make you change your opinion?

I have had the pour over the waxup fracture and get a fin sticking up but it was the same color afte!r removing the fin and plaster that adhered to the fin and palate as those were white simply from no separator and they had stone stuck there.

 

[kimba]

Hi JMN,
I have had that as well , but this wasnt plaster in the acrylic

 

[Doris A]

Thanks for your reply Doris,
The lines where not quite onthe edge of the denture , about 2 -3 mm up from the foodline. This is why i put it out there, I am unsure if it was seporator or dry acylic. as neither quite makes sense . I think the line was right where some flasking stone overlapped the waxup. Does this make you change your opinion?

I’m still thinking dry acrylic. When trial packing, do you flatten the acrylic into a patty before you add it to the flask? The edge of the patty could’ve been dry and when pressed It created the lines. It was probably the last bit of acrylic added before closing the flask. Are they keeping a lid on the mixing cup during packing?

 

[sidesh0wb0b]

post a pic?

 

[JMN]

Hi JMN,
I have had that as well , but this wasnt plaster in the acrylic

My next shot would be to see if there was a time difference in packing vs the normal. Was there a phone call, a 'quick' emergency potty break, time spent looking for something, or just anything that would have left the last trial pack material in the jar/cup/mix vessel while the rest was sealed in the flask. It happens.

I think Doris is on the right track, you have a craze line from incomplete polymerization between two regions. Just figuring out why is the trick.

The other, but unlikely, scenario is that they had mixed more than one batch and got out of touch with which was which.

 

[Doris A]

My next shot would be to see if there was a time difference in packing vs the normal. Was there a phone call, a 'quick' emergency potty break, time spent looking for something, or just anything that would have left the last trial pack material in the jar/cup/mix vessel while the rest was sealed in the flask. It happens.

I think Doris is on the right track, you have a craze line from incomplete polymerization between two regions. Just figuring out why is the trick.

The other, but unlikely, scenario is that they had mixed more than one batch and got out of touch with which was which.

I just thought of another possibility. The person packing is a trainee, maybe they don't know not to reuse acrylic that's already been packed, as in flash. Maybe they needed a little more acrylic and they repacked the flash. That would cause what is being seen. Just a thought.

 

[kimba]

Thanks all for feedback.
Sorry sideshow I dont have a pic as I had to fix it and get it out.
Good thoughts Doris and Jmn. I am leaning toward drying out betwwen trial and final pack.
the most frustrating thing is the person involved doesnt seem to want to entertain the thought it was something they did.
Thanks for everyones feedback

 

[JMN]

[...]
the most frustrating thing is the person involved doesnt seem to want to entertain the thought it was something they did.
[...]

Gotta nip that in the bud like now, yesterday even. It's ALWAYS something we do. The material does nothing aside from age all by itself.

Dude, I hope you find out for sure, but not with it happening again

 

[kimba]

Thanks JMN , I agree wholeheartedly.
Its a mindset issue, whenever I have a problem my first thought is what did I do wrong.
I have seen many others who,s first thought is whts wrong with the material.
Its the old "the model just broke " syndrome

 

[FASTFNGR]

Hi All,
had my trainee removable tech bring me a case they processed with 2 thin white lines in the acrylic. Near the palatal periphery on each side of a horse shoe style single central denture.
Its very faint, but there.
Any ideas
Thanks in advance. Sorry no photo as I had to get it fixed and out

Porosity or acrylic mixed with tin foil substitute?

 

[JMN]

Thanks JMN , I agree wholeheartedly.
Its a mindset issue, whenever I have a problem my first thought is what did I do wrong.
I have seen many others who,s first thought is whts wrong with the material.
Its the old "the model just broke " syndrome

Rent Driving Mrs Daisy and tell them to watch it. Just the first 15 minutes. Then you can always tell them after that 'Moma, cars do not behave, they are behaved upon"

 

[Flipperlady]

Hi All,
had my trainee removable tech bring me a case they processed with 2 thin white lines in the acrylic. Near the palatal periphery on each side of a horse shoe style single central denture.
Its very faint, but there.
Any ideas
Thanks in advance. Sorry no photo as I had to get it fixed and out

It's the trial packing, you needed to add a bit more acrylic and do an extra trial pack or two.

 

[kimba]

Hi Flippercentral,
so you think its might be porosity? It didnt look like it to me , but have you see this thin line before ?

 

[Flipperlady]

Hi Flippercentral,
so you think its might be porosity? It didnt look like it to me , but have you see this thin line before ?

Of course it's always helpful to post a pic just to make sure,but based on what you're saying, I've seen the white line on palatal and ridge areas generally on cases that have deep vaults or thicker cases. I've learned to always go back and add pea sized pieces of acrylic to those areas and trial pack a few more times/let it sit under pressure for awhile before processing.

 

[kimba]

Thanks Flippercentral,
I wish I had taken a photo, but as I sais I had to get it out. It wasnt a thick area, just the palatal flange of a small horesshoe singe central denture.
I also add pea size acrcrlic on my final pack, as to whether this was done we will never know.
Thanks again for your feed back