MODEL-LESS!!!!

[Smithwick0208]

As the digital impression work picks up, we are doing more and more model-less crowns. What kind of limitations are y'all putting on model-less cases? Max units? Bridges? Just trying to set a standard to limit the variables for failure.

 

[rkm rdt]

I would start with Lava Ultimate.

 

[eyeloveteeth]

why? we do mode-less zirlux, e.max, lava ultimate... i actually have this idea for model-less PFM that i want to try LOL

the only thing to be aware of so far that I see - if you have consecutive units, try not to glaze the contacts between the units...you will invariably create tightness that the doctor will then complain and grind and possibly open the contact...

instead just hand polish those areas since it won't be seen anyway.

 

[Smithwick0208]

We do Ultimate, Bruxzir, and EmaxCad now. My question is more on the lines of span. I haven't done too many over 2 units splinted. Mainly because of designing the case "perfect", without having to adjust embrasures, ridges, etc...

 

[Smithwick0208]

why? we do mode-less zirlux, e.max, lava ultimate... i actually have this idea for model-less PFM that i want to try LOL

the only thing to be aware of so far that I see - if you have consecutive units, try not to glaze the contacts between the units...you will invariably create tightness that the doctor will then complain and grind and possibly open the contact...

instead just hand polish those areas since it won't be seen anyway.

I'm curious of this idea of yours. I have been pondering on how to do it consistently. We print our anatomy and seal to the frameworks.

 

[rkm rdt]

I would be comfortable with 2 units or a 3 unit bridge at maximum.

After that I would prefer a model. If the patient requires more than 3 teeth then they can wait for it to be done properly.

 

[Smithwick0208]

the only thing to be aware of so far that I see - if you have consecutive units, try not to glaze the contacts between the units...you will invariably create tightness that the doctor will then complain and grind and possibly open the contact...

instead just hand polish those areas since it won't be seen anyway.

How big are you going with these? I have seen some 5 units BZ bridges with 1-2 pontics. I wouldn't think anything that big would be good on the anterior anyway, since embrasures don't always come out like designed.

 

[eyeloveteeth]

we aren't doing anything beyond 3 units - although i have done a few 6 unit model-less mandibular bridges - 1 had 4 pontics, with successful seats.


for a PFM - my idea was to take a plaster impression of a full contour milled in wax and to paint vasoline over the "die" - then just build to that mold - LOL ...it probably doesn't work, but in my mind i want to think it is possible.

Paint the inside of the plaster with lipstick and voila.


Or as i'm typing this...actually since stone expands, it should be able to slot inside without rubbing off any lipstick. -


NOW I DIDN'T SAY THIS WOULD SAVE TIME, just thinking lol.



Seem to me alot of labs are having a hard time doing pressed e.max model-less, but we have been relatively successful.


relative because we really haven't done enough to make a grandiose conclusion

 

[Smithwick0208]

What die would you be using if it was a model-less case? Are you printing/milling one from the digital impression file? We are milling out EmaxCAD for the model-less Emax cases. I have done about 5 or so pressed and luckily I didn't have any problems. As long as they can sprue to the lingual and not affect the cusp height, it should go pretty smoothly.

 

[eyeloveteeth]

yeah, you'd have to print the die - DP1200?? lol


print the die, print the coping, make an index/matrix of the crown on die - then build up crown, finish so it fits inside the matrix haha...


probably not very accurate, but i imagine weird cr@p all the time.

 

[Smithwick0208]

There is probably a way to do this somewhat accurately. I know GL was working on this a little over a year ago.

 

[eyeloveteeth]

who's GL? green latern? #wishfulthinking

 

[Smithwick0208]

ha ha Glidewell. I don't know if they ended up having success with it, but I know they were doing some testing.

 

[eyeloveteeth]

ha ha Glidewell. I don't know if they ended up having success with it, but I know they were doing some testing.

lol it seems i have a lot of ideas similar to Glidewell..... turns our my CT scanning idea was also thought of @ glidewell - and we ended up seeing the same vendor.


I bet with the adoption of a low shrinkage porcelain, this is totally do-able. Just have to figure out the correct process of splitting the "matrix" without jeopardizing too much in fit integrity

any one care to try? I'd do it, but I never have enough free time to do hands on stuff like that

 

[Smithwick0208]

lol it seems i have a lot of ideas similar to Glidewell..... turns our my CT scanning idea was also thought of @ glidewell - and we ended up seeing the same vendor.


I bet with the adoption of a low shrinkage porcelain, this is totally do-able. Just have to figure out the correct process of splitting the "matrix" without jeopardizing too much in fit integrity

any one care to try? I'd do it, but I never have enough free time to do hands on stuff like that

I feel ya. You have as much as they do tied up in R&D, you have plenty of ideas floating around. If I can get some time set aside, I'll mess around with some different techniques and see what happens.

 

[eyeloveteeth]

that new Ceramco procelain is very low in shrinkage right? I really think it has the potential to work,

 

[rkm rdt]

I think a nano composite is a better way to go.

The Dr is always tweeking contacts and occlusion with conventional techniques however with a direct composite addition ,they can add a contact quite easily if needed.

 

[eyeloveteeth]

yeah but then i can just mill a full contour lava ultimate.

I'm saying as a way to make a model-less unit for custom porcelain build up lol

 

[rkm rdt]

yeah but then i can just mill a full contour lava ultimate.

I'm saying as a way to make a model-less unit for custom porcelain build up lol

That's what I'm saying.

I want time to build up the porcelain and I still want a model as well.
The whole purpose of a layered restoration is for you to apply your artistic skills to the case. I don't see the advantage of restricting your ability to make it esthetic.

Monolithic makes more sense for modeless. LU seems like the best type of material for this.

 

[eyeloveteeth]

actually i would say the Crystal Ultra from DLMS is better than LU - but we were hypothesizing just in general of offering model-less for everything.


Of course personally, hand polished Full Contour Zirconia would be the easiest LOL - LU is weird and I dont like the way it looks.