digital inaccuracies

[drock]

Hi all,

I have received both trios and planmeca scan files from two different Drs, and produced the crowns digitally and printed our own models. Both resulted in poorly fitted crowns, of course the crowns fit fairly good on the printed models but in the mouth the Drs couldn't seat them in. I not sure where to go from here or how to resolve the problem.
I have the stratasys Eden 260vs printer and we're using 3 shape. Does anyone have a lot of success with this workflow and any ideas on how to improve the accuracy here. Is this a I/O scanning problem or are the parameters of our 3shape software off somewhere?

 

[rkm rdt]

Your parameters are off.
My Trios drs send me love letters.

 

[zero_zero]

My Trios drs send me love letters.

Too much information...

 

[rkm rdt]

Too much information...

They smell like mouthwash too.

....anyway digital is accurate.

 

[CoolHandLuke]

so accurate in fact, some here disregard the model stage completely for single and full contour work.

if its a question of not seating then one of several things may be happening.

1. you didnt add compensation for undercuts, so the units literally will not sit down in the patient because the margin is narrower than the prep.

2. the spacer is not enough. doc puts more cement than necessary and the unit as a result sits high and has open margins.

3. your margins are placed too high in 3shape.

4. doc did not use tissue cord and margins are overhanged with tissue.

5. someone tried to smooth out a hole in the scan and reduced the die. poor resulting fit.

its very easy to screw up, but when you know whats going on, its a walk in the park.

9/10 cases for me dont need models.

eden260v, and 3shape here as well.

 

[cadfan]

Your parameters are off.
My Trios drs send me love letters.

with lipstick and perfume on ??? maybe another reason.

 

[rkm rdt]

with lipstick and perfume on ??? maybe another reason.

Sorry, I haven't transitioned to exocad just yet

 

[CoolHandLuke]

don't assume you arent making novice mistakes either. i just got through YET ANOTHER free end bridge that i didn't get the bite right in the scan.

i know what i should be doing to fix it - but i keep somehow not doing it.

10 years working with 3shape and im still making idiot mistakes with bites.

 

[Sevan P]

I never had to change any parameters on my trios files. Only the inlays were tight. Loosened the spacer a bit and it was fixed. I did scan a printed model in once and it was tight in the mouth with the same setting as my digital files are done with. But that's is why you never scan a printed model in. A good way to see what is wrong is have the dr do a pvs impression and a trios scan of the same case like a single crown. Design on the trios file and cut then see if it fits the poured model, this is how u got my inlays to fit.

Sent from my SM-G920V using Tapatalk

 

[rkm rdt]

don't assume you arent making novice mistakes either. i just got through YET ANOTHER free end bridge that i didn't get the bite right in the scan.

i know what i should be doing to fix it - but i keep somehow not doing it.

10 years working with 3shape and im still making idiot mistakes with bites.

It takes most tech and dentists 10 years just to realize that they will never completely understand occlusion in the life of their careers.

 

[CoolHandLuke]

i dunno how true that is, but i fear for the safety of my job and my continued existence in this career if i can't get it right.

 

[rkm rdt]

i dunno how true that is, but i fear for the safety of my job and my continued existence in this career if i can't get it right.

Get your hands on a hanau articulator and get the denture guys to show you how to set up denture teeth. Learn in wax.

 

[CoolHandLuke]

why do i need to learn that? i just have to fix the model room's poor articulations before i scan, and then scan the right bite instead of assume the plaster room has any clue what they are doing.

 

[zero_zero]

Screw-ups do happen time to time, from misaligned scanbodies to bites etc.

 

[Gru]

Your parameters are off.
My Trios drs send me love letters.

Your mother is a dentist?

 

[JohnWilson]

I think the telling statement is "fit fairly good on the printed model"

IF ITS NOT FITTING BANG ON PERFECT IN THE LAB.... YADA YADA YADA