Exocad crown occlusal problems with intra oral scans (Will mail top shelf Scotch if you can help me)

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Hi all, I'm at my wits end and have exhausted all of my mental ability and effort troubleshooting bite scan inaccuracy through intra oral scan cases we get from our clients. I would be more than happy to send a high end bottle of scotch or your preferred drink of choice if you can solve this once and for all for me. Yes, I'm that desperate for help.

I use exocad, and I have been unable to design a crown with any reliability regarding the occlusal accuracy if it is from an intraorally scanned case. Two different clients I work with use the 3M TruDef scanner. When I finish margin marking and load the exo. case file into exocad after margin marking, nearly every time the Trudef bitescan aligns the jaw scans in a way where they intersect each other significantly. I would say on average the occlusal plane of the jaw scans are intersecting about .4mm, and in some cases almost as much as 1mm or even more. Exocad recommends cutting away the scan inaccuracy, which if I proceed to do, will just gouge out the antagonist scan, which I highly doubt is accurate. Otherwise my only other choice is to leave the jaw scan unaltered, and do my best to reposition the antagonist so it has even contact everywhere. Obviously this is taking a guess at the patients centric bite, but it seems much more likely to be accurate than cutting out the opposing. I'd say the most common occlusion problem is the crown is too tall and the dr has to spend significant time grinding it down, in some cases much of the anatomy is lost. Of course, this is not how it is designed, and when I mill and test it on the 3d printed model, it is perfectly represented as it is in the CAD. When the Dr. puts it in the mouth, margins and proximal fit are usually perfect, but occlusion is almost always high.

I've been fighting this for two years, have tried many different solutions with no consistent accuracy, to the point where one of the dentists has stopped sending me digital cases and is sending them to a digital specialty lab, and I guess the lab has been getting great results. So obviously they have a reliable workflow, and I have not figured it out. I have self taught myself full arch hybrid cases with perfect seating results, but I can't figure this out...dental cad is bitch slapping me right now. Can anyone give me advice on how they use exocad to ensure close to accurate bite relationships so your crown occlusion is close to perfect at seating? Do you let Exocad cut away scan accuracies as recommended by Exocad? Are there any other details to consider? I do not have this problem when I scan cases in on my desktop scanner and design the crown, and my margins and proximal contacts are usually perfect. Just occlusion....just the goddamn intra-orally scanned occlusion. I really appreciate you all here, great forum and lab techs. Thank you so much for reading. And I'm very serious about the Scotch offer.

-Matt
 
ps2thtec

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Hi all, I'm at my wits end and have exhausted all of my mental ability and effort troubleshooting bite scan inaccuracy through intra oral scan cases we get from our clients. I would be more than happy to send a high end bottle of scotch or your preferred drink of choice if you can solve this once and for all for me. Yes, I'm that desperate for help.

I use exocad, and I have been unable to design a crown with any reliability regarding the occlusal accuracy if it is from an intraorally scanned case. Two different clients I work with use the 3M TruDef scanner. When I finish margin marking and load the exo. case file into exocad after margin marking, nearly every time the Trudef bitescan aligns the jaw scans in a way where they intersect each other significantly. I would say on average the occlusal plane of the jaw scans are intersecting about .4mm, and in some cases almost as much as 1mm or even more. Exocad recommends cutting away the scan inaccuracy, which if I proceed to do, will just gouge out the antagonist scan, which I highly doubt is accurate. Otherwise my only other choice is to leave the jaw scan unaltered, and do my best to reposition the antagonist so it has even contact everywhere. Obviously this is taking a guess at the patients centric bite, but it seems much more likely to be accurate than cutting out the opposing. I'd say the most common occlusion problem is the crown is too tall and the dr has to spend significant time grinding it down, in some cases much of the anatomy is lost. Of course, this is not how it is designed, and when I mill and test it on the 3d printed model, it is perfectly represented as it is in the CAD. When the Dr. puts it in the mouth, margins and proximal fit are usually perfect, but occlusion is almost always high.

I've been fighting this for two years, have tried many different solutions with no consistent accuracy, to the point where one of the dentists has stopped sending me digital cases and is sending them to a digital specialty lab, and I guess the lab has been getting great results. So obviously they have a reliable workflow, and I have not figured it out. I have self taught myself full arch hybrid cases with perfect seating results, but I can't figure this out...dental cad is bitch slapping me right now. Can anyone give me advice on how they use exocad to ensure close to accurate bite relationships so your crown occlusion is close to perfect at seating? Do you let Exocad cut away scan accuracies as recommended by Exocad? Are there any other details to consider? I do not have this problem when I scan cases in on my desktop scanner and design the crown, and my margins and proximal contacts are usually perfect. Just occlusion....just the goddamn intra-orally scanned occlusion. I really appreciate you all here, great forum and lab techs. Thank you so much for reading. And I'm very serious about the Scotch offer.

-Matt

Hello miltonic, Check these pics and see if this is similar to your issue.


299C0946-4E15-4938-818D-E5360384B38D.jpeg 8E43E72B-A28C-449A-B3B5-0B60C8E83019.jpeg 9D46F922-5C9A-455C-AEF5-10326AE001B9.jpeg
 
Sda36

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Hello miltonic, Check these pics and see if this is similar to your issue.


View attachment 38092 View attachment 38093 View attachment 38094
I think he's discussing upon entering set up articulator settings once in Start Articulator in expert mode-tools. Wish I could help more here, virtual articulator can be murky for sure. Need to set which teeth to include in function selection. Choose all anteriors and in only quadrant, choose any distal teeth to help with lateral guidance. I ask my IOS clients to scan in at least both canines, max. and mand. Just try to figure out which teeth "May" be affecting guidence on a given case and select them.

Also, a good while back, 2thmkr 🙂 suggested going to antagonist in expert mode, I usually go after performing articulator functions and right click to bring a menu. Select correct to antagonist, you'll get a warning, choose ignore. I step Down .1mm ×3-4 times usually to allow for glazing materials. You will see intrusion into opposing model for sure and if you don't, something is really off the rails.

My understanding with IOS is that when bite scans are recorded, it's imperative to ask the patient to swallow, this puts the arches into minor compression, fully interdigitated as best can be. Sometimes there are also artifacts on scans that can show up as considerable bite intrusions but must be evaluated per case ie tripod posts on printed models.

Hope this helps in some way.
 
ps2thtec

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I think there are two issues presented. The first is to repair Max. Intersection, as my first pic. Usually I see the #, .2.... or .1...., and first pic is 2.402.
I always choose Repair, and proceed as normal. But with a big repair #, I found recently that I do not repair, but go to Expert, and pull up from white bar menu ”Orient”. Set a path position. Go back to Wizzard. Then the destroyed opposing issue is no more.
[Thanks 2th & CW]
The other issue presented is high occlusion. With all cases, I do a Correct to Antagonist step. Find in Expert, try click on models to find menu, and gennerally click down 3 times together a green color. Finish design and I cut antagonist to .15. That solves my high occlusion problems most times. I all run all cases through Vitual Articulator to help remove high spots in excusion.
At least thats my work flow......
 
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CoolHandLuke

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you have 4 tools available as of the Galway release.

1. in expert mode, right click your scan and select Correct Jaw Scan Relation
2. in expert mode, right click your Antagonist and select Correct Antagonist
3. in expert mode, right click either scan and select Model Alignment (this assumes you have a bite scan that you can verify)
4. in Expert mode, click Tools, select Articulator. during the articulator setup it will detect intrusions; you should have minimal intrusions from the previous 3 options if you have aligned the data correctly. you will finish aligning the scans to the articulator and this message appears


articulator setup.png

once you click don't modify scan data it will immediately want to know how you'd prefer to handle the overclosed bite - by opening the models along the Z, or by opening the pin. it is my opinion that opening the pin is better. opening with the pin will open the models until no intrusions are found, so rearticulating using the first TWO methods by creating some small intrusions in the correct areas, aligning using pt's wear facets, all the usual tricks of doing it by hand are integral to fixing your bites by opening the pin. then again if you press Cancel here, you will hold on to your alignment and keep the bite as fixed, so if you get good you will be able to keep your newly fixed bite.

open articulator.png
 
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3 shape
I’d prefer a 55 gallon drum of crown royal special reserve
 
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First off, thanks for your responses everyone, I really appreciate you sharing your techniques with me. I had a chance to read all the responses here, and I'm attempting to apply them on a current case right now. I'm responding to each of your responses, you can find your name below where I respond to you all personally. I will post pics to show you how I'm trying to apply my current case to your techniques. I definitely have questions.

ps2thtec: The pics you posted are correct, that is what I'm referring to and I will post a pic of my current case. In my screenshot, the max intrusion for this case is .313mm. Ok, so I looked at your pic, and see you have a max intrusion of 2.4mm!!! When you click repair, it cuts away the all the antagonist tooth and creates huge wear facets. I guess this is one of my main questions, how can this be accurate to do this? The patients teeth don't look like that cut away , how can we confidently alter the teeth like that when they arent cut away like that in real life? The logic part of my brain does not agree with this at all, can you help me with the rationalization of this being an accurate thing to do? In your 2nd response, you said if the intrusion is significant then you go to expert mode and click orient, then 'set a path position'. I have seen the orient from time to time but was not able to see this option in expert mode so I'm not sure what I need to do to bring that up, do I need to be at the beginning of the wizard and have certain jaw scans selected in order to see that option? I have been using 'Correct Antagonist' myself recently, but 've been trying to manually orient the antagonist so I get all dark blue marks (very light occlusion),that line up with visible wear facets. Do you do this? or just alter height only? And you said you prefer to have the occlusion showing to be moderate with green intensity, which is like .4mm of occlusal interference right? Wouldn't it be better to show blue for minimal interference? Just trying to understand your workflow better, thank you for sharing so far.

Sda36: I followed your workflow, loaded virtual articulator, selected which teeth to function in articulation, then corrected the antagonist and dropped it down two times and have green intensity intrusion. I'll post pics to show you. It seems you are in agreement with ps2thtec, in that you are accepting an intrusion of approximately .4mm through the occlusal plane as acceptable to design your restoration to. I'm having a hard time understanding why this is accurate but now two of you are saying the same thing so I'm not understanding the logic that seems to be working for you both. If you have the jaw scans aligned with each other so that they are intersecting through the occlusal plane of each other by .4mm, and design the tooth to this plane, when you go to put it in the mouth, it would be out of occlusal contact by .4mm because the teeth wouldn't be able to occlude/pass through each other in real life, right? I get what you are saying about making space for your glaze, but why couldn't I just try to articulate the bite with minimal intrusion (blue),that is balanced and lines up with wear facets, then design the crown to this and then cut the crown like.1-.2 mm max for glaze, and check contacts on a finished printed model? Are the IO scans distorted to begin with, so the intrusion is accurate? My contention with IO scans are that they use a single side bite scan to line up the jaws with no cross arch error checking, and the bitescan is often not able to accurately line up the jaws accurately and this is where the jaw intersect occurs. But is there also warping or distortion of the jaw scans that is causing this intersection? Is 'repair' an accurate solution, say for anything that is .4mm or less, not counting obvious artifacts? I'm making the assumption that the jaw scans are accurate but the bite scan placement of them is off. Is this correct? Or in your experience can jaw scans be distorted? If so, what can we possibly trust to be accurate?

CoolHandLuke: I followed your articulator steps, first attemping to correct antagonist in order to see if I could hand articulate better, but I actually was not able to hand articulate better than how the scan came in, even though there is a .311 mm intrusion. I tend to not like using the IO bite scans within Exocad to align jaws, it doesn't seem to give a better alignment than what 3M aligns on it's end when the case gets loaded in. So that said, I started up Articulator and in this case I still have the same amount of intrusion (.311 mm) that I started out the case with since I couldn't improve the antagonist manually. I aligned the occlusal plane as best I could in the articulator, then selected 'Don't modify Data', then selected 'open pin' and the bite is now open in the anterior in the articulator. I started the articulator and it recorded excursions, then closed the bite back to original placement. At this point I'm back to where I started with the original bite. What am I missing here? Do I design to this and cut away intrusions now? Or leave the intrusions and design restoration to this, print the model and final bite check after glaze on printed models?

Can you all explain your experience with the accuracy of these bite scans? Does repair give you the best results? I used to do repair but I was all over the board with accuracy, Somtimes it was perfect, sometimes open bite. Sometimes too heavy. So I stopped using repair. I started manually adjusting anagonist, but with quadrant scan it is difficult to know for sure. I had better results, but still too many problems, usually too heavy bite. Can you comment on my case, what you see and how you'd approach it? Just leave it as is and repair scans, or don't repair? Then after crown is designed, just cut away .1mm intersect to allow for glaze? Ultimately, I'd like to gain understanding of why a process works rather than just memorizing steps and accpeting it on faith. If you repair, why is that accurate? Is it because the scan data is truly inaccurate? Because repair will give a signifcantly different occusal relationship, than not to repair. Thanks for everyone's responses so far, please help me understand your reasoning better!

Gratefully,

Matt

Also apologies, I took screen shots of my case and can't see how to attach them to this thread, it seems I can only insert URL address and not upload the images directly...
 
Doris A

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First off, thanks for your responses everyone, I really appreciate you sharing your techniques with me. I had a chance to read all the responses here, and I'm attempting to apply them on a current case right now. I'm responding to each of your responses, you can find your name below where I respond to you all personally. I will post pics to show you how I'm trying to apply my current case to your techniques. I definitely have questions.

ps2thtec: The pics you posted are correct, that is what I'm referring to and I will post a pic of my current case. In my screenshot, the max intrusion for this case is .313mm. Ok, so I looked at your pic, and see you have a max intrusion of 2.4mm!!! When you click repair, it cuts away the all the antagonist tooth and creates huge wear facets. I guess this is one of my main questions, how can this be accurate to do this? The patients teeth don't look like that cut away , how can we confidently alter the teeth like that when they arent cut away like that in real life? The logic part of my brain does not agree with this at all, can you help me with the rationalization of this being an accurate thing to do? In your 2nd response, you said if the intrusion is significant then you go to expert mode and click orient, then 'set a path position'. I have seen the orient from time to time but was not able to see this option in expert mode so I'm not sure what I need to do to bring that up, do I need to be at the beginning of the wizard and have certain jaw scans selected in order to see that option? I have been using 'Correct Antagonist' myself recently, but 've been trying to manually orient the antagonist so I get all dark blue marks (very light occlusion),that line up with visible wear facets. Do you do this? or just alter height only? And you said you prefer to have the occlusion showing to be moderate with green intensity, which is like .4mm of occlusal interference right? Wouldn't it be better to show blue for minimal interference? Just trying to understand your workflow better, thank you for sharing so far.

Sda36: I followed your workflow, loaded virtual articulator, selected which teeth to function in articulation, then corrected the antagonist and dropped it down two times and have green intensity intrusion. I'll post pics to show you. It seems you are in agreement with ps2thtec, in that you are accepting an intrusion of approximately .4mm through the occlusal plane as acceptable to design your restoration to. I'm having a hard time understanding why this is accurate but now two of you are saying the same thing so I'm not understanding the logic that seems to be working for you both. If you have the jaw scans aligned with each other so that they are intersecting through the occlusal plane of each other by .4mm, and design the tooth to this plane, when you go to put it in the mouth, it would be out of occlusal contact by .4mm because the teeth wouldn't be able to occlude/pass through each other in real life, right? I get what you are saying about making space for your glaze, but why couldn't I just try to articulate the bite with minimal intrusion (blue),that is balanced and lines up with wear facets, then design the crown to this and then cut the crown like.1-.2 mm max for glaze, and check contacts on a finished printed model? Are the IO scans distorted to begin with, so the intrusion is accurate? My contention with IO scans are that they use a single side bite scan to line up the jaws with no cross arch error checking, and the bitescan is often not able to accurately line up the jaws accurately and this is where the jaw intersect occurs. But is there also warping or distortion of the jaw scans that is causing this intersection? Is 'repair' an accurate solution, say for anything that is .4mm or less, not counting obvious artifacts? I'm making the assumption that the jaw scans are accurate but the bite scan placement of them is off. Is this correct? Or in your experience can jaw scans be distorted? If so, what can we possibly trust to be accurate?

CoolHandLuke: I followed your articulator steps, first attemping to correct antagonist in order to see if I could hand articulate better, but I actually was not able to hand articulate better than how the scan came in, even though there is a .311 mm intrusion. I tend to not like using the IO bite scans within Exocad to align jaws, it doesn't seem to give a better alignment than what 3M aligns on it's end when the case gets loaded in. So that said, I started up Articulator and in this case I still have the same amount of intrusion (.311 mm) that I started out the case with since I couldn't improve the antagonist manually. I aligned the occlusal plane as best I could in the articulator, then selected 'Don't modify Data', then selected 'open pin' and the bite is now open in the anterior in the articulator. I started the articulator and it recorded excursions, then closed the bite back to original placement. At this point I'm back to where I started with the original bite. What am I missing here? Do I design to this and cut away intrusions now? Or leave the intrusions and design restoration to this, print the model and final bite check after glaze on printed models?

Can you all explain your experience with the accuracy of these bite scans? Does repair give you the best results? I used to do repair but I was all over the board with accuracy, Somtimes it was perfect, sometimes open bite. Sometimes too heavy. So I stopped using repair. I started manually adjusting anagonist, but with quadrant scan it is difficult to know for sure. I had better results, but still too many problems, usually too heavy bite. Can you comment on my case, what you see and how you'd approach it? Just leave it as is and repair scans, or don't repair? Then after crown is designed, just cut away .1mm intersect to allow for glaze? Ultimately, I'd like to gain understanding of why a process works rather than just memorizing steps and accpeting it on faith. If you repair, why is that accurate? Is it because the scan data is truly inaccurate? Because repair will give a signifcantly different occusal relationship, than not to repair. Thanks for everyone's responses so far, please help me understand your reasoning better!

Gratefully,

Matt

Also apologies, I took screen shots of my case and can't see how to attach them to this thread, it seems I can only insert URL address and not upload the images directly...
You can't post pictures until you have at least 5 posts.
 
CoolHandLuke

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Matt, it may help you to make models first, and scan them the way they hand articulate, i suspect if you are unable to save the new relationship that this may be your only recourse. mention to your doctors to scan more data - half arches were invented to save impression material, theres no excuse for poor bites with digital scans and half arches make alignment less accurate.

to directly address your concerns, you are right, these intrusions are NOT accurate, and the software was not designed to let you get away with a bad bite. it always lets you know that in fact the articulation of the scans IS wrong, because it shows intrusions. 3shape doesnt show any of this unless you specifically look for it, letting you go through life dead eyed and lazy.

you are supposed to be able to see and account for this.

the fact that you are having such trouble speaks to the quality of your exocad training, moreover speaks to the training given to your docs that they send them no matter what the screen shows. a poor scan forces you to start in poor conditions, just like a poor impression, and i thought the name of the game of digital was MORE accuracy not MORE lazyness.

your exocad should also come with about 36 different Sample cases for you to use to play with the different tools. i suggest you to play with some of their implant/bridge cases to get a feel for re-articulation because truly some of them are scanned wrong on purpose to give you this opportunity. case ending in -024 should be an anterior implant case with a wrong bite. try playing with this, the adjusting of antagonist is fairly easy and straightforward and should give you a feel for digital hand articulation.
 
Affinity

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Never had luck getting accurate occlusion in CAD. Especially in exocad. Having to manipulate 3D models accurately is like chasing your tail..
 
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Matt, it may help you to make models first, and scan them the way they hand articulate, i suspect if you are unable to save the new relationship that this may be your only recourse. mention to your doctors to scan more data - half arches were invented to save impression material, theres no excuse for poor bites with digital scans and half arches make alignment less accurate.

to directly address your concerns, you are right, these intrusions are NOT accurate, and the software was not designed to let you get away with a bad bite. it always lets you know that in fact the articulation of the scans IS wrong, because it shows intrusions. 3shape doesnt show any of this unless you specifically look for it, letting you go through life dead eyed and lazy.

you are supposed to be able to see and account for this.

the fact that you are having such trouble speaks to the quality of your exocad training, moreover speaks to the training given to your docs that they send them no matter what the screen shows. a poor scan forces you to start in poor conditions, just like a poor impression, and i thought the name of the game of digital was MORE accuracy not MORE lazyness.

your exocad should also come with about 36 different Sample cases for you to use to play with the different tools. i suggest you to play with some of their implant/bridge cases to get a feel for re-articulation because truly some of them are scanned wrong on purpose to give you this opportunity. case ending in -024 should be an anterior implant case with a wrong bite. try playing with this, the adjusting of antagonist is fairly easy and straightforward and should give you a feel for digital hand articulation.
Hi Luke, thanks for sticking with me. I won't argue with you that maybe I'm totally missing something. I want to assure you that I do have a lot of experience with hand articulation, and feel very confident in my ability to find centric with the 'Correct Antagonist' feature, I was in removables with my dad's lab for years and made about 2000+ bite splints, and hundreds of dentures and I had to trust in my hand articulation usually more than the bites that the Dr's sent, and my articulation was dead on probably 95-98% of the time. I work with a master ceramist, who has 4 years of cad experience on Dental Wings, and he is running into the same problem with that CAD software as well regarding these intraoral scans. We are both just stumped at how to fix this with either Exocad or Wings. We deliberated printing the models first and rescanning them in, but not only is this a lot of extra work, it is adding in potential distortion of printing an introral scan, then rescanning again. Our results have gotten better since we started manually repositioning the bite rather than just trusting what came in from the IO scanner. But we are still having problems. One of the dentists has been sending most of the IO cases now to a lab that specializes in digital model-less restorations, and they are able to take these files and get accurate results at seating for occlusion without even using a model to test proximal or occlusal contacts...they obviously have a dialed in reliable workflow to pull this off. I don't know what software, or settings they are using to be able to have their techs realign the bite and design to such accuracy, because when I get these scans the bites are always off and I have not found the magic formula.

Would you mind explaining a little more about opening the pin strategy? I'm not totally understanding how the process is correcting the bite. Lets say I digitally re-articulate the bite as best I can with 'Correct Antagonist'. After that I open Articulator. It will detect remaining intrusions. I open the pin to remove all intrusions....then what? this is where I'm lost. Do I save the jaw relationship to this new open pin position? what am I doing next to adjust? Thanks for helping me this far.
 
ps2thtec

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There’s a lot there Matt, let me try to hit on some.....
- As in my 2nd pic/ 3D data editor, when I see the pink intersection and huge # I do not do Repair. Hit Expert and white menu strip (hidden on bottom of screen) has Orient. After setting an occlusal view, OK ,and go back to Wizzard. The 3d editor will not be there anymore. Just continue your steps. I usually do my Correct Antagonist step while still in
Wizard// Place Model Tooth. Like I previously mentioned, in the Adjust toAntagonist step I use .15, because if I would use a much higher # such as .24 my anatomy would be more wiped out. Most times bites are not shifted, just need to correct the height.
With IOS I find it to be a crap shoot. I can do what I do on all my cases the same and still end up with a crown I need to adjust more than I would like to. ( I don t have faith in it but “the Pt loves it Compared to a real impression”) So as for accuracy all I hear is how great the crowns fit. We can only do with the information given. We do our best and they love.
-The mouth is a dynamic place and teeth are always mobile. I make crowns Slightly out of occlusion. My theory is, the patient bites down, and clinches, and compresses the ligaments of the teeth. That is something we cannot replicate on models in our hand.
- On rare occasions there will a case in 3D Editor with No Bad intrusions detected.(no repair ).
Have also seen bite fine on screen from file,but off when I have the model in my hand.
It’s an imperfect world and we do our best.
 
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CoolHandLuke

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Hi Luke, thanks for sticking with me. I won't argue with you that maybe I'm totally missing something. I want to assure you that I do have a lot of experience with hand articulation, and feel very confident in my ability to find centric with the 'Correct Antagonist' feature, I was in removables with my dad's lab for years and made about 2000+ bite splints, and hundreds of dentures and I had to trust in my hand articulation usually more than the bites that the Dr's sent, and my articulation was dead on probably 95-98% of the time. I work with a master ceramist, who has 4 years of cad experience on Dental Wings, and he is running into the same problem with that CAD software as well regarding these intraoral scans. We are both just stumped at how to fix this with either Exocad or Wings. We deliberated printing the models first and rescanning them in, but not only is this a lot of extra work, it is adding in potential distortion of printing an introral scan, then rescanning again. Our results have gotten better since we started manually repositioning the bite rather than just trusting what came in from the IO scanner. But we are still having problems. One of the dentists has been sending most of the IO cases now to a lab that specializes in digital model-less restorations, and they are able to take these files and get accurate results at seating for occlusion without even using a model to test proximal or occlusal contacts...they obviously have a dialed in reliable workflow to pull this off. I don't know what software, or settings they are using to be able to have their techs realign the bite and design to such accuracy, because when I get these scans the bites are always off and I have not found the magic formula.

Would you mind explaining a little more about opening the pin strategy? I'm not totally understanding how the process is correcting the bite. Lets say I digitally re-articulate the bite as best I can with 'Correct Antagonist'. After that I open Articulator. It will detect remaining intrusions. I open the pin to remove all intrusions....then what? this is where I'm lost. Do I save the jaw relationship to this new open pin position? what am I doing next to adjust? Thanks for helping me this far.
you'll want to use Correct antagonist and create overclosing in a uniform way, along the wear facets that exist, and then let the Articulator open those intrusions. if they are uniform, the act of opening should bring the scans to the correct bite. if the intrusions are not uniform, the bite will appear very open.

exocad's approach to this is either to give you a truly vertical opening by shifting everything along the Z or by using the theoretical patient approximation of the articulator hinge to open the jaws, which is why i suggested this to begin with.

however what you can then do is save the new relationship by exporting the scene as one stl or object file before proceeding with any design; once done, you can use this as the bite scan instead, and when aligned with the bite scan, it doesnt matter what the articulator does, they will spring back to the same spot everytime.

you can also use 3rd party software like blender, meshmixer, meshlab, etc, to re-orient and realign data. that lab's skill with mesh work probably stems from some years of familiarity with the digital space so i'm not sure what tools they'd use because everyone's bag of tricks varies; i've given you what i'd do in exocad. this is usually good enough to create jaw relationships with better centric relation and when push comes to shove there's always your software support who should be experienced enough to help you no matter what the problem is. over the years the go-to-answer for any product question of "what do i buy" has always culminated in "the product with the best support" usually for exactly these reasons.
 
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These are great responses, thank you ps2thtec and CoolHandLuke. It sounds like there is no perfect solution for what we have to work with Exocad but there are some really helpful tips here that might make my overall approximations come out better. You guys want to split the bottle? :) Send me your home address in private message and I'll send something your way. Really appreciate your insights.

-Matt
 
Gru

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Ha! This is the first thread since I joined dln that stayed on track! Who knew all it would take was the offer of a little booze! Congrats, Matt, you’ve accomplished something thought heretofore impossible! And maybe even will find a solution too! I’ll be glad to help if the Wizards here can’t, but they’re likely better than me! Cheers! Beer
 
CoolHandLuke

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Matt if you stick around and spark/participate in discussion that'll be payment enough. i try to be as helpful as possible these days, because its actually more enjoyable than posting memes or whatever.
 
ps2thtec

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These are great responses, thank you ps2thtec and CoolHandLuke. It sounds like there is no perfect solution for what we have to work with Exocad but there are some really helpful tips here that might make my overall approximations come out better. You guys want to split the bottle? :) Send me your home address in private message and I'll send something your way. Really appreciate your insights.

-Matt

hey Matt, I think it’s more like there’s no perfect solution when you work with ios.😉
I’d really like to know if any of the “tricks ” actually work to solve issues youre having.
I agree with Cool hand, that we just want to help out here, and have a little fun yucking it up from time to time. I’ve gotten lots of answers here myself , and basically plagerize what I’ve learned to help others. All good!
 

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