Best way to orient dental splint for printing

Hello,

I am currently printing occlusal splints/nightguards with the NextDent Ortho resin, which are coming out great on Dental SG profile in Open Mode.

I just want to see if I can make it even better for myself. What would be the best way to orient this model so that any supports would be on the “sides” of the nightguard, and not where the teeth fit, or the opposite side where the opposing teeth would hit. I was kinda hoping for a vertical print.

Below is what I currently have set up, and its about the best I can get. Only 7-8 supports on the underside. Any advice would be appreciated!

FORM file: Google Drive: Sign-in

You’ve done a pretty great job with this as is. Printing vertical is feasible for smaller objects like rings, but doesn’t work as well for things with greater volume. There aren’t really any sizable constructive changes I could make. If you were going for ease of printing and stability, angling a bit more in the X axis would help, (45 degree angles work well) but it sounds like you’re looking to minimize supports and this should print perfectly well.

1 Like

Hello Yderkl,
I printed a splint with grey resin at 25 um, didn´t go well, did not fit. think the gravity made his job an was little bit longer than the dental model. attache pics
how was you experience with the ortho resin? you get the desire result? it cures well? do you use a post cure device?

Thanks Frew,

The main reason I ask is because the Prosthodontist Formlabs has been marketing with, Dr. Michael Scherer DMD, has a youtube video online of printing dental models completely vertical without supports:

How do you think he is able to get accurate dental models with the process outlined above? It seems like he is committing every cardinal Formlabs sin (print directly on build plate, totally vertical, AND no supports). And since he is kinda the dental spokesperson for Formlabs, I figured he knows what he’s doing. Just curious on your thoughts?

1 Like

I am getting excellent results with NextDent Ortho Clear, printed in Open Mode, with Dental SG resin profile @ 0.05mm resolution.

In fact, the final product has an EXCELLENT thermoplastic quality to it, so when I go to deliver the splint, I submerge it in very hot water for 10-15 seconds, and then insert intra-orally. The splint becomes flexible and slightly malleable, so they are fitting extremely well every time.

For post processing, I just follow the directions that come with the resin. It’s like a 10-20 minutes IPA soak and then 10-20 minute post cure.

Now if only I could find software to make the splints that doesn’t cost more than the printer itself!!

1 Like
  1. What software are you using currently to design your occlusal splints? 3shape? Exocad? Something else?

  2. What is your estimated cost per splint with the NextDent resin?

  3. If you have to heat it up to insert, that doesn’t seem like “great fit” to me, but a great final result with a work around :slight_smile:

  4. My Form2 is on the way, I’m super interested in Occlusal Guards with it. I am also a hobbyist developer of Blender. I may kick off a project to make an occlusal guard designer in Blender. What would your ideal cost for an occlusal guard software be?

Best,
Patrick

@PatrickMoore It is wonderful to see you here my friend! I e-mailed you awhile back after watching literally all of your youtube videos. I also have posted a few times on the Zoho discussion board (Kevin Yoder) for your software. You are a legend in my opinion!

  1. The splints that I have actually fabricated for patients were designed using 3shape, by my lab technician - I have just recently started to learn that software for myself. I cannot afford 3shape, so I had to work out a deal with my lab where I will print splints for him if he lets me use his scanner and software on Fridays.

I have also used your software, Open Dental CAD, in Blender, to fabricate some basic splints - essentially custom trays. But I ran into some problems with a particular python variable error at a certain point during design. Additionally, since (as far as I know) there is not articulator functionality in ODC as of yet, I cannot appropriately design the occlusion.

I have also used Meshmixer to get the same custom tray type of splint that I can get with ODC.

Lastly, I am currently learning OnShape to see if there is a viable way to replicate articulation, and then virtually “grind” in the ideal bilateral even contact on closure and anterior guidance during excursions (like the 3shape software does).

  1. 1 L of NextDent Clear Ortho is $294 (say $325 after shipping), I have found that most occlusal splints require 8-10 mL including supports, so if I can print 100 splints with 1 L of resin (1 L / 10 mL), then each splint would cost me $3.25 a splint. This does not take into account amortization of the Form2 or the 3Shape software.

  2. I hear you loud and clear! It just seems like there are so many potential sources of error in taking impressions, pouring up models, sometimes duplicating models, scanning them in, converting between softwares and then ultimately 3D printing with unique batches of resin, trays that have variable use, unique orientations, custom supports and post cure warpage/shrinkage, that any wiggle room I can have on final delivery is greatly appreciated by me and my patients :slight_smile:

  3. Brother, I have been waiting for this moment for quite some time (ie. a software that only focuses on splint design without paying for all the other stuff I would never use). Since I can almost design splints for free, and I am just lacking the occlusal design portion, I think a fair price would be $100-$1000? That doesn’t include the typical dental tax either. That would be up to you :slight_smile:

Looking forward to hear from you, and you are going to LOVE your Form2. I advise getting the Pro Service Plan as well!

-Kevin

I need to revisit this.

1 Like

Now that I watch that again, you pretty much have the whole workflow completed with ODC…

Mount on your virtual articulator --> open pin to 1-2mm space in the posterior --> block out undercuts on maxillary arch --> create shell of maxillary arch 1.5 - 2.5 mm offset thickness --> run excursion/protrusion script on mandible --> boolean with shell --> touch up.

I think the only thing different from 3shape is adding a flat U plane to the occlusal of the shell before the boolean with mandibular arch?

A flat u plane? Interesting, it’s kind of same concept as a wax rim…

I am gonna buy a 3D printer to our lab and are looking at Formlabs Form 2. I want to use NextDent Ortho Clear for making bite splints. On NextDents website they write that Ortho Clear only works with wavelengts 365-385 and the Form 2 uses 405.

How did you do a workaround for this? I can see that you are getting good results with the splints.

Thanks in advance,

Pia

Pia,

Very good question, and unfortunately I do not have the answer you are looking for. Here is some more information that they gave me.



Obvious Preface: I am not qualified to properly interpret these slides.

But It seems like this resin has two photoinitiators, and it appears as if “Photoinitiator 1 / Yellow” is indeed, photosensitive at 405 nm. “Photoinitiator 2 / Clear” appears as if it would never begin to polymerize with a 405 nm laser. Maybe the highest wavelength it is photosensitive at is 375-380 nm, and even then, it is just barely photosensitive.

In the documentation they give you with your purchase, the recommended post-cure wavelength is 315-400 nm, which is a slightly broader spectrum then the “365-385 nm” listed on their site, albeit, it is referring to post curing and not actual printing.

My best guess would be that, at least one of the two photoiniators is getting catalyzed by the 405 nm laser (apparently enough to physically create a properly bonded model). Probably ideally, multiple wavelengths or a spectrum of wavelengths emitted at once would achieve the most photoiniation, and the least amount of complications during printing. I am also guessing that with my CureBox from @pmcgarr which post cures at both 365/405 nm, I might be polymerizing that other photoinitiator so the final product would be similar to a splint printed with DLP.

Additionally, I was doing a little research, and I noticed that the company that actually makes the NextDent resin (Vertex Dental B.V.), sells it as a private label as well. When I dug a little deeper, I saw that the product name “NextDent Clear Ortho” was synonymous with Formlabs upcoming splint material, “Dental LT Clear.”

Again, I am no expert on these things, but it seems to me, that as far as the FDA is concerned, they are the same product. Following that logic, if Formlabs is releasing their “Dental LT Clear” aka “NextDent Ortho Clear” that has been tested by Formlabs with their own machines and quality control, then theoretically we don’t have to worry about the specific mechanisms of photoinitation, as they feel it is curing properly. Might be a stretch, but that’s all I got so far! :slight_smile:

What do you think?

1 Like

Thanks a lot for your explanations! I really feel satisfied with my choice of printer and resin, then :wink:

I would advise to print the splints always either flat or at an angle of max 45 degrees, depending on the undercuts. Just make sure you have as least overhanging sides on the inside of the splint as possible. Also I think the sheets show you why the Ortho Clear resin should not work on 405 nm printers. The resin is probably very unstable with 405 nm lightsources.

Yes, but it does. And some of their resins are different (namely Gingiva Mask and Custom Tray), so I’m not sure which resins these graphs represent to be honest.

What do you mean by unstable? Every print I have every done in NextDent Ortho Clear came out flawlessly. The final products also seem to have the ideal mechanical properties as well.

1 Like

It appears the formlabs printer went beyond their own expactations. the sheets show that it has a UV-initiator in it and no daylight initiator and that, that is the reason it is clear (as I interpretret it ). Perhaps it still has some reactivity at 405 and is the laser powerfull enough to cure the resin.

If it is designed for 385 nm it probably has no blocker for 405 in it which should make it unstable (theoretically), but again perhaps the laser system is better at this than dlp systems.

1 Like

Spokesperson does not equal “knows what he is doing”, but that isn’t necessarily bad unless we make the assumption, … which we know not to do. I am just happy to see others benefitting from the FL printers, and helping FL continue to push the envelope.

I would like to be able to print the NextDent ortho resin on my F1+ instead of fiddling with the F2. I have 3Shape Ortho and Dental Premium, but would like to avoid paying extra for Appliance designer. I have heard of labs using the dental suite to make basic ‘splints’, like implant guides, but my design (NLA) is much more sophisticated. I wish there was a limited trial license (limited to a few cases, not time on the clock). It is great to hear that your OrthoResin splint fit well. I was considering getting the B9 Core 530 and putting it in open mode to get the accuracy, but your experience is very encouraging. Would love to stick with FL (except for print time, of course).

I post process with a vacuum curing unit that gives me the most beautiful surfaces. I have a commercial one by ESPE in the NorCal office, but am building one using a pyrex bottom, which acrylic lid, and 1 stage vacuum pump (shining nail salon fluorescents in through the glass). The ESPE unit is also glass chamber with surrounding UV bulbs. Formlabs was interested in the process a few years ago when developing their curing station, but they needed a bigger chamber.

1 Like

Do we know if FL is doing the wise thing of licensing the NextDent FDA resins and then optimizing the parameters for the 2 FL printers?

Years ago, before FL1+ changed everything in the 3D printing world, I was negotiating with DWS about their resins and how they decided which order to release them in. They told me that the amount of manpower they used to optimize so many parameters for each resin was the limiting factor. I realize that it is a little easier now, but there are so many factors. It is amazing how well things turn out, as it is (I mean for dental, where accuracy is so important). I bought the F!+ over the B9 Creator based on the vagueness of calibrating the B9 (which is solved with the Core?). I felt that, despite the larger laser spot size, FL was able to get greater repeatability. Now I know that is not entirely true (for any resin-based printer) because tank aging (as well as other factors) will result in slight undercuring, and consequently dimensionally smaller models or bigger holes. That might work out for splint designs?

1 Like

Thanks for all help. Print with NextDent Ortho Clear works just fine, but I have a slight color problem. The splints turns out to be yellow and not really clear when I have them ready and postcured. Any suggestions to avoid this?

Try a fresh build plate and a fresh vat. When dealing with biocompatibility, it is necessary to keep everything separate from your normal resins and printing. Do you think there is any chance the ortho clear might be slightly contaminated by a different resin left behind somewhere inconspicuous? Just thinking out loud…