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hattmalltoday at 5:28 PM8 repliesview on HN

So shouldn't this really be something that could be opened sourced. I think I've seen a few write ups of people that did their own, but seems like a highly functional implementation could be democratized.


Replies

ivan_gammeltoday at 6:06 PM

It is definitely not that simple for a number of reasons. Yes, aligners and retainers in theory may be printed on some commercially available hardware. At your own risk, because you will be printing a medical device and you will need:

1. A treatment plan: simulated movement of teeth at every step, taking into account all forces. That’s specialized software or external lab service.

2. Precision. You put too much pressure at the wrong angle and you will need a surgery to fix the damage, because the tooth root moved in wrong direction.

3. Plastic. You cannot use ordinary 3D printer ink. You need a plastic that can survive the chemical environment in your mouth, maintain the pressure, and you probably want it to look good (no discoloration etc).

4. Finish: Align Tech, Straumann etc do not stop after 3D printing, there are few other steps involved to make sure there’s no sharp edges etc.

5. Maybe you will need attachments (to focus pressure in the right direction on certain teeth) or wires.

Align Tech is Apple of clear aligners, but now competition exists, producing aligners at scale is commercially more efficient, considering all the risks and required qualifications, and of course the best materials for aligners are patented and not sold OTC to everyone.

Disclosure: I worked at Align 10 years ago and later was CTO of European DTC competitor.

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afavourtoday at 5:57 PM

I did Invisalign a few years ago. Manufacturing the retainers is surely only a small part of the puzzle.

They used a specialized sort of 3D camera on a stick to get an incredibly accurate model of my mouth, any open source solution would need an equivalent. And you’d also need open source code from somewhere to work out which teeth need to move where and at what stage in the treatment.

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kube-systemtoday at 6:15 PM

Orthodontics is simply “making a retainer” the same way orthopedics is simply “putting screws in a leg”.

The difficult part is not the manufacturing, but knowing how to do it properly so you don’t harm the patient.

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Legend2440today at 5:43 PM

Certainly it's not impossible to DIY, but it's more difficult than just popping some aligners on your 3d printer.

Manufacturing them requires a resin printer and a vacuforming setup, but that's still the easy part. It's a whole system with a dental 3D scanner, software for rearranging your mouth, and attachment points that have to be epoxied onto (and later removed from) your teeth by a dentist.

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plommetoday at 6:28 PM

A point I didn’t see sibling comments make is that the dentist often has to file between teeth for them to sit and align correctly. They did so several times in my case. I would not want to do that to myself!

sithadmintoday at 6:56 PM

It’s been tried, with some success. Pretty sure I’ve seen a post here on HN from someone that DIy’d it end to end.

But it’s also something that’s not responsible to shortcut. Shifting teeth around too fast can result in permanent root damage and even loss of teeth. There was a whole cottage industry in the US for a while focused on under cutting Invisalign with a reverse-engineered product, but they often moved on accelerated treatment timelines that caused a not-insignificant amount of harm to patients, and cut corners on intake (DIY at home mold kits) that also contributed to problems. Pretty sure all of the companies doing this are basically dead now.

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adrrtoday at 6:08 PM

Need expensive printers and you need CAD software that can correctly move the teeth. Also not all it can be done by software, sometimes you need to blank out certain teeth that dentist will make the call.