I came across this article yesterday:
http://www.materialise.com/en/press-releases/materialise-first-company-to-receive-fda-clearance-for-diagnostic-3d-printed
To save you the trouble, QUOTE:
" In August 2017, the FDA announced that software intended to create output files used for printing 3D patient-specific anatomical models which are used for diagnostic purposes, is a class II medical device and requires regulatory clearance. "
@Jory @Frew @Formlabs - Since a lot of us are using your printer, and your software, to generate supports and bases for our anatomical dental models, and are delivering occlusal splints to actual patients, can you please provide us with PreFormās FDA class II medical device documentation, so we can all be in compliance.
Thank you so much!!
-Kevin
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If your are using it to make actual custom parts- if THAT really ādiagnosticā? Seems to me that is ātreatmentā, not diagnosis.
I mean- the model you build you already know what the condition is you are building it to treat, right? You have already diagnosed, when you use the printer you are effecting treatment.
First off, I donāt really have a stake one way or the other. I just want to make sure we are all following the law, and treating our patients safely.
I would love to play devilās advocate though:
Letās say I take a mold of a patientās teeth and want to print it as a diagnostic model, which is very routine in dentistry - get a set of diagnostic models first, then define a treatment plan.
Or we can say that I took a mold to make an occlusal splint for a patient. Either way, the analogy will work
- In the most technical sense, is there any difference at all in the partās geometry when it is imported into a software as an OBJ vs an STL file?
- Are you sure? Would you bet your front teeth on it?
- When Preform says your file that you know for a fact is manifold and has no errors, actually has an error and needs to be ārepairedā on import, what repairs are actually being done, and would they affect the partās geometry or physical strength properties after it was printed? Small changes in 3D files can make HUGE differences in those properties.
- When you are finally ready to print, either a dental splint or an anatomical model, will the parts be accurate if they are oriented completely vertical? If not, Preform should not allow these orientations to be printed. An ill-fitting oral appliance that was directly fabricated, or indirectly fabricated based on an anatomical model, could do some serious damage to a patientās teeth and/or jaw/TMJ.
- Now that you are comfortable with your orientation, what about adding supports? That will certainly change the geometry of the original part. Depending on your experience level, you could end up with far too many supports that could adversely effect the outer detail of the part, or even worse, if supports made it to the fitting surface of the appliance (the intaglio), then it would make the actual fit of the part less accurate (no matter how you remove supports, you will be polishing areas of the parts that do not need adjustment, and are introducing inaccuracies to the final part. If a little nub is missed when post processing, and it happens to be on the biting surface of the part, I could foresee many cracked teeth.
- āBut I donāt use supports when printing my models and splintsā. My response would be, have you compensated for compression layers? Without supports are you absolutely positive every angle on your part is less than 19 degrees from level, or there are no overhangs greater than 1 mm? If you arenāt, would the print deform in those areas, but still possibly appear as if it was accurate, leading to more issues down the road? What if these models were being printed for fabrication of orthodontic aligners, the problem would be compounded by 20 or 30x.
I would guess that these are the types of things the FDA will be looking at, but Iām just speculating, and also playing devilās advocate 
Based upon the statement from Materialise, it doesnāt exclude regulation on software for therapeutic purposes. Simply says diagnostic requires regulation.
Any source document for the August 2017 FDA announcement? I searched but couldnāt find anything.
The basic definition for Software as a Medical Device does seem to apply to Preform though since it appears to be marketed towards making dental surgical guides. I would guess it is Category II based off of this framework: http://www.imdrf.org/docs/imdrf/final/technical/imdrf-tech-140918-samd-framework-risk-categorization-141013.pdf
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We are all having a mysteriously difficult time coming up with the sourceā¦
not sure about the ramificationsā¦ I mean, what could Formlabs possibly tell a regulatory body that would assuage the fear that some doofus using their machine doesnāt understand not to āscaleā the print?
ALL they can do is certify the dental resins as bioinert, and say what the TOLERANCE of the printer is regarding size.
If prefrom or the printer automatically scales the print to compensate for different resinās shrinkage ratesā¦ again, there will be a plus or minus tolerance that is NEVER gonna be zero.
For that matter- how does an oral scanner stack up in terms of aliasing a surface or true accuracy?
I mean if taking a physcial impression you can know what the spec sheet for the alginate or silicone is regarding shrinkageā¦ but then that is compounded by what you cast your pattern in and the actual final material- right? But the impression prints a molecule for molecule form- while the best oral scanner on earth is a gross approximation by comparison?
But NONE of this is diagnostic? It seems to me diagnostic refers to measuring and evaluating.
An xray is diagnostic. But a filling is NOT.
And software that is diagnostic would be like a system that tunes CAT data into imagesā¦ or that āreadsā images or slides or other materials for the purpose of detecting a tumor, or a cavity, thru algorithms.
If we are gonna rely on a program to detect cancer in images no radiologists even sees, then absolutely that software needs to be vetted and regulated.
But the From 2 is more analogus to a Davis Root Tip Teaser, Or a Hu Friedy scalerā¦ its a tool used to treat that, in the hands of a clutz, no regulation can make more steady.
Or am I way off the mark?
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Therapeutic devices are most definitely regulated by the FDA. The two you mentioned have to go through FDA clearance of some sort.
Dentists are relying on Preform to accurately transform a STL file to print data, and also relying on the printer hardware/firmware to generate an accurate physical representation of the STL file. The program that takes a scan and creates a STL file is most definitely regulated by the FDA. Not sure how Preform would get around that. Now sure how the printers themselves would get around that too thoughā¦
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I donāt think there is any getting around it.
NO 3D software, anywhere on earth can promise perfect accuracy- there will always be a rounding error as to pointsā position in space.
While a scanner might capture a million points on a surface- that is almost no information when compared to what a dental impression captures about a surface.
But both are subject to operator error that the makers of the materials and devices simply can not quantify.
An oral scanner would be diagnostic and it would be subject to certification to verify that it adequately can do its job without tranferring infections from one patient to anotherā¦ but where is the antiseptic protocol for the Form 2? it never goes anywhere near the patient or any potentially contaminated part of the patient. it doesnāt have to prove that it has a disposable bioguard.
you print a surgical guide- that guide meets the patient- but is disposed of and never sees the printer again.
no Printer manufacturer can provide absolute data on output, either.
They canāt even tell you an exact figure for how far off they averageā¦ all they can do is approximate the tolerance for given resins at given operating temperatures.
But a dentist who defeats the machines automation to run third party resins at setting he or she comes up with is gonna get entirely different resultsā¦
so again, What could the government possibly medically certify about a Form 2 or its software that isnāt clearly stated in the specs of the machine?
They can verify the RESIN as safe, and I suppose they can verify that the LT Tank and platform and wiper arm do not contaminate the resin part in any wayā¦ Hu Friedy can verify that their explorers are made out of surgical steelā¦ but beyond thatā¦ what? Nothing the government can verify will make the guy holding the thing less likely to puncture your gums with it.
i guess I just donāt get it.
there is no way that a Form 2 or its software qualify as ādiagnosticā and if they donāt then what does a regulation affecting diagnostic devices have to do with it?
Iām not sure bioinert is the same as biocompatible. I donāt know if any biocompatible 3D resins are technically bioinert. If a biocompatible resin is not printed or processed exactly as the resin manufacturer has indicated, itās entirely possible - and probably even very probable - that the part is in fact not biocompatible at all. There could be an enormous amount of photoiniators that did not react, therefore creating residual and leaking monomers from the part. Even if you made the case that the scaffold of the part printed, so post-curing would eliminate the residual monomers, it better be with the correct UV spectrum, or you will still end up with a non-compliant part.
For example, FormCure only emits 405nm, and all of the NextDent resins have dual photoiniators that polymerize in the spectrum from 300nm-550nm. Iām not sure it would ever be possible to get a truly safe/biocompatible part with that set up - and many are doing just that and even delivering to patients!
Iāve always felt like this feels too āwild westyā right nowā¦A lot of confounding variablesā¦ maybe the FDA is feeling the same way?
If I was making dental guides as a service for dental offices (therefore I am a medical device manufacturer), I would not be able to get away with what Dentists are doing in their offices today. That is the short answer.
Yoderkiās second post is spot on in terms of the potential issues with the system. They coincide largely with the FDAās guidance on 3D printing medical devices also. https://www.fda.gov/downloads/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocuments/UCM499809.pdf
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Nope. Get ready for some bullshit. As I understand it, dental labs actually have no regulations, or things to comply to. True story, I can set up a lab in my garage right now, get an LLC as a āmanufacturerā not medical devices, and smoke cigarettes all day and not wash my hands and fabricate crown and bridge. All I need is an Rx from a dentist. Dentists are the ones ultimately responsible for infection control and proper fit so the liability falls on them. Even if it went to court, I have some protection with my LLC. Not joking. Now, the good labs will comply to a standard that they themselves have created, but itās not legally required in any way.
edit: upon re-reading, I feel like there are some bold claims. I want to re-iterate āas I understand it,ā yet still about 90-95% sure
edit 2: and to be totally fair, the labs I talk to hate it and are trying to push legislation to change it. To ensure safety, it costs money. Labs have to pay premium prices for the well known and well researched name brand materials, and they are losing business to shitty labs that donāt care and get their inventory from cheaper shady places.
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The reality is that any physician can write a prescription for anything - that is a power that they have. They can write a prescription for an implant made from balsa wood and cyanide and if someone will make it for them they can put it in.
That said, many hospitals have requirements in place (that are ultimately coming from their insurance providers) that prohibit a lot of the cowboy stuff. Dentistry, being mostly operated out of private practices, has less of a check system in place. It used to be a common approach to early clinical data with a new medical device, but that door is pretty much shut these days (as well it probably should be).
In terms of software, Preform is not being marketed as software to create dental implants, guides, etc. If they start marketing it as such the FDA will come knocking. If some dental labs use it as a tool, that is their choice.
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