Going model less.

[rkm rdt]

Now that we are receiving more IOS each day, I would like to know your thoughts on going model less.

I see the benefits to the lab but what advantage does it give to the dr and patient other than saving a few dollars? I am not against it but I have a hard time working without a safety net too.

Is this a wise direction so early on in the IOS game?
...or do I just suck at cad design?

 

[2thm8kr]

I don't think you suck at CAD design. It is very hard to give up models and live/think in the virtual world.
I am working in that direction. I am up to about three abutting (posterior) units, single or splinted and getting consistent results.
The next time I get a quadrant of crowns or a four unit posterior bridge I am going to give it a go.
The benefit to me are less expense as you said, but also getting work through the lab a little quicker because I am not waiting for
the models to ship to me, over time that increases my productivity by getting a few more units out each week. It is weird having a case pan
with just a RX and a crown rolling around in the bottom.

 

[TheLabGuy]

I'm not sure I would jump in with both feet if it was me. I'd take the cautionary trek on this journey. At first, have the Doc send a traditional impression along with scan...do that a few times to make sure the scan and the impression crowns are exact with the digital models you are producing. Then I would do quite a few of digital models and crowns and verify a couple things...1. that you're not adjusting anything (i.e. adding a contact, adjusting occlusion, etc...) from the crowns via the digital models. 2. That the Doc is dropping them straight in, no or very slight adjustments. Once you have that track record with them, then I would feel comfortable...I'd have to build up my confidence before making that leap to no models. I guess it really depends in the end on how fast you get to #1 and #2...then again, maybe you're already there.

 

[2thm8kr]

I'm not sure I would jump in with both feet if it was me. I'd take the cautionary trek on this journey. At first, have the Doc send a traditional impression along with scan...do that a few times to make sure the scan and the impression crowns are exact with the digital models you are producing. Then I would do quite a few of digital models and crowns and verify a couple things...1. that you're not adjusting anything (i.e. adding a contact, adjusting occlusion, etc...) from the crowns via the digital models. 2. That the Doc is dropping them straight in, no or very slight adjustments. Once you have that track record with them, then I would feel comfortable...I'd have to build up my confidence before making that leap to no models. I guess it really depends in the end on how fast you get to #1 and #2...then again, maybe you're already there.

Solid advice! That is pretty close to the technique that I have been using. When I first started trying model less, I had a doc that I work closely with take a small impression of the area after the scans. I would design the crowns and mill then I try them on the models to compare the virtual design to reality. After dialing in my settings, we started trying single posteriors without models. I would go to the office during the seating appointment and see if any adjustments were made.
We would discuss the fit and any adjustments and I would go back and look at the design files and compare notes and take a screen shot of the contact strength for future reference. It really is no different than working out your stone model technique to eliminate the variables and get more accurate models. I am finding that the scans are way more accurate than any stone model. We do have an occasional stinker now and then, but no more so than with traditional techniques.

 

[TheLabGuy]

Solid advice! That is pretty close to the technique that I have been using. When I first started trying model less, I had a doc that I work closely with take a small impression of the area after the scans. I would design the crowns and mill then I try them on the models to compare the virtual design to reality. After dialing in my settings, we started trying single posteriors without models. I would go to the office during the seating appointment and see if any adjustments were made.
We would discuss the fit and any adjustments and I would go back and look at the design files and compare notes and take a screen shot of the contact strength for future reference. It really is no different than working out your stone model technique to eliminate the variables and get more accurate models. I am finding that the scans are way more accurate than any stone model. We do have an occasional stinker now and then, but no more so than with traditional techniques.

That's awesome right there!!! As our industry progresses (as it should) this is my current protocol (what I posted). A back story on this...is that I almost loss a phenomenal client because I jumped right into the digital models from the scans I was getting. Heck, I was even getting around Itero and making my own digital models, that shlt backfired big time. Very rare (has only happened twice) that I have had to send a refund check out to a Doc, but I did to this one. The models (several of them) were all way off...looked awesome on the screen. Heck, I was all jazzed up, slapped some sexy ceramics on them and then I got that dreaded call So that left a bad taste in my mouth per say and I'm probably much more cautious when it comes to just 'jumping' in per say as it pertains to the virtual world. To finish the story, the Doc was really surprised that I wrote a check out (around a few thousand I think) and sent it that I was able to salvage the relationship. Still though, I'm not one for tucking my tail between my legs and that sucked, so my advice and your protocol 2thm8kr is something most folks should take to heart. Hope that helps.

 

[NicelyMKV]

I was very excited at first. After working with several different printed models I realized there were inaccuracies in the models. Some large and some small.

My accounts often mention how there is virtually zero adjustments on my work. One of the things I pride my lab on. I've always worked very hard on interproximals contacts and occlusal contacts( I do not just drop them out a me). The virtual articulator sin these cad systems are phenomenal..... But not 100% accurate. They are no where near the range of movement I get by hand on articulated models. There again, I'm not going to just drop everything out a mile to eliminate all possible lateral interferences. I also see inaccuracies in the mounts on some cases when scanned in. We have tested this quite a bit. I will stick a bite under my microscope with a hot glue gun. Scan it in and the system snaps the scans to the articulated scan. Open it up to design and see minute space between the occlusal contacts. We have started manually checking and closing the bites on some cases within the cad software. So, in my opinion, it's not accurate enough yet. But, that's just me

One more thing.... When I glaze fcz, emax or anything else monolithic, there is a chance of a slightly thicker layer interproximals or on the occlusion sometimes. Just the way it is. Seems to me like the only sure thing is to leave interproximals super tight and occlusion a way out of you go modeless..... That's exactly the opposite of why my doctors use me, and the exact opposite of how I want to do business.... Just my two cents.

Jason

 

[rkm rdt]

I agree with the slow approach to this. The last thing you want is to do is feed into any lingering doubts about digital that our friends at Sirona have created.

I want my digital models to be as accurate as the mouth so maybe there is room for improvement in that area as well.

I'm looking at this from different perspectives and you guys are spot on when it comes to dialing in everything.That is the advantage of digital for sure.You have measurable results.
My biggest challenge seems to be in changing the mindset of certain clients.I have been fortunate to work with two drs that are now all in.

We are making everything with models from Argen and are having good results. However I still need to tweek contacts , especially with implant cases.
I am encouraging the drs to "improve" the adjacent contacts to reduce the embrassures when scanning.

Perhaps the guided surgery software will help with better implant placement because right now ,I find it's a free for all when it comes to angulation and site placement. Path of insertions are a nightmare and this is where I find I need to tweek most of my contacts. Yes I'm talking monolithic screw retained here.

I was having issues with open bites from the models. Argen tech support advised me that I need to utilize the optimize occlusion feature and 2D cross section window. I've noticed that even though you may get what appears to be an ideal centric, scanning the bite registration can open the teeth slightly if the dr retracts the cheek too much. ***( shameless plug)*** check out Trios Study Club on FB for more on this.

Here's another angle that I have considered. I think there is a wow factor in delivering a digital model. Every patient that I have met during scanning has asked me if the teeth are 3D printed . They love it when they see their name printed on the side. This is a huge marketing advantage for the dentist as well if you print the clinic name too.

 

[2thm8kr]

I was very excited at first. After working with several different printed models I realized there were inaccuracies in the models. Some large and some small.

My accounts often mention how there is virtually zero adjustments on my work. One of the things I pride my lab on. I've always worked very hard on interproximals contacts and occlusal contacts( I do not just drop them out a me). The virtual articulator sin these cad systems are phenomenal..... But not 100% accurate. They are no where near the range of movement I get by hand on articulated models. There again, I'm not going to just drop everything out a mile to eliminate all possible lateral interferences. I also see inaccuracies in the mounts on some cases when scanned in. We have tested this quite a bit. I will stick a bite under my microscope with a hot glue gun. Scan it in and the system snaps the scans to the articulated scan. Open it up to design and see minute space between the occlusal contacts. We have started manually checking and closing the bites on some cases within the cad software. So, in my opinion, it's not accurate enough yet. But, that's just me

One more thing.... When I glaze fcz, emax or anything else monolithic, there is a chance of a slightly thicker layer interproximals or on the occlusion sometimes. Just the way it is. Seems to me like the only sure thing is to leave interproximals super tight and occlusion a way out of you go modeless..... That's exactly the opposite of why my doctors use me, and the exact opposite of how I want to do business.... Just my two cents.

Jason

I don't trust the virtual articulators completely yet. I would not (at this time) do a large case especially if it involved a cuspid with out models. The bite registrations from intra oral scans record the bite with the ligaments in compression so there is no need to equilibrate like a stone model. There are a few basic principles I use for single posteriors that I call 'forensic evidence' whether using stone or virtual models. To explain this I will need to take a bunch of screen shots and I don't have time for that now, but I will post at another time. When you get your settings dialed in the occlusion is most times spot on and when checked in the mouth with articulation ribbon it holds when tugged with forceps. NO reason to leave them infra occluded. Not every one is absolutely perfect and I attribute this to the movement of the teeth or abrasion of the temps. If you can deliver the crown in a shorter amount of time there is less chance of inaccuracies.

 

[CoolHandLuke]

yes, often optimizing the bite will close it, but not always. especially on tiny scans.

its easy to go model-free, you just need to keep continuous lines of communication open. have the doc call ahead of the case, call in the middle of design to ask a question (that the majority of the time you know the answer to),and call as it is going out the door.

in a month this doc will take any advice you give to heart; we've noticed that we get the best results with a full half arch to fully optimize occlusion so take a bigger scan. OK will do. we notice a lot of your shades using the trios get quite dark, can you send the patient to shade match at the lab. sure no problem.

 

[RJS8669]

Been working with a Tru-Def account doing this. its funny - we went through the dialing-in process and she was pretty happy, then we had a crown on #18 that required a fair bit of adjustment and now she's telling me to take everything further out of occlusion. Personally, I think this is a mistake, but the lady helps pay my bills. Unfortunately, there are a million reasons why one crown might be high and another perfect, and not all of them are under our control. Sometimes I ponder that a large part of going model-less is setting realistic expectations for the client...

 

[rkm rdt]

There are days in this profession when the phrase " realisitic expectations" induces snot bubbles.

 

[RJS8669]

I am currently between laughing and crying - its my daily state of mind....

 

[rkm rdt]

RJ8669

 

[rkm rdt]

never mind

 

[CoolHandLuke]

don't try to link dropbox images. its not going to go well.

 

[PDC]

I'm not sure I would jump in with both feet if it was me. I'd take the cautionary trek on this journey. At first, have the Doc send a traditional impression along with scan...do that a few times to make sure the scan and the impression crowns are exact with the digital models you are producing. Then I would do quite a few of digital models and crowns and verify a couple things...1. that you're not adjusting anything (i.e. adding a contact, adjusting occlusion, etc...) from the crowns via the digital models. 2. That the Doc is dropping them straight in, no or very slight adjustments. Once you have that track record with them, then I would feel comfortable...I'd have to build up my confidence before making that leap to no models. I guess it really depends in the end on how fast you get to #1 and #2...then again, maybe you're already there.

This is a good idea Rob. The problem I've been having lately with Itero is their digital bite scans don't match what I get on the physical models. The virtual bite may be open slightly but it will be closed on the articulated milled models. So what happens is even though my settings are creating a .3 clearances on the occlusal of the crown, it ends up being high.

I don't know what the heck is happening. I just sent some photos to Itero support with explanations of this. Maybe I should manually close the virtual bite and do the occlusal adjustment. Maybe I'll just make a coping because that's probably what it will look like after all that adjustment.

 

[TheLabGuy]

This is a good idea Rob. The problem I've been having lately with Itero is their digital bite scans don't match what I get on the physical models. The virtual bite may be open slightly but it will be closed on the articulated milled models. So what happens is even though my settings are creating a .3 clearances on the occlusal of the crown, it ends up being high.

I don't know what the heck is happening. I just sent some photos to Itero support with explanations of this. Maybe I should manually close the virtual bite and do the occlusal adjustment. Maybe I'll just make a coping because that's probably what it will look like after all that adjustment.

Not sure about Itero, I use to have the system back in the day at another lab. I hated those milled models, and the fees were ridiculous, but that was many moons ago. I would like to add to my previous comment and give a shout out to those Canadian Trios members here. We have had incredible accuracy and consistency with the trios chairside scanner. I'm so anal, I don't even have 3shape anything in my lab, but we have a couple docs that have trios and even using a outside lab to do the model design, and printing, still very consistent. I'm almost to the point, and I can't believe I'm going to say this, where I get the 3Shape communicate for our lab. It's been so accurate, I wouldn't have a problem going modelless on those trios clients. Or maybe, that opens up the door to get a printer and start printing some models yourself.

 

[2thm8kr]

I can't believe I'm going to say this, where I get the 3Shape communicate for our lab.

Perish the thought.

 

[TheLabGuy]

Perish the thought.

reason being?

 

[2thm8kr]

reason being?

Next thing you know you'll be eating esrom cheese.
Seriously, is there really a reason to purchase communicate? I understand if you want the client to have the ease of just click and send, but it is really easy to bypass.