This is something that's in your mouth a lot and constantly exposed to saliva.
The Dimension 1200es mentioned doesn't appear to be specific to medical applications. The product page lists the only compatible thermoplastic being ABSplus-P430. The MSDS for that basically says the stuff is dangerous in molten form, and beyond that there's very little data. The same company makes "Dental and Bio-Compatible" materials for use with their other products, and these appear to have considerably more safety data.
>The aligner steps have been printed, in addition to a “riser” that I added in order to make sure the vacuum forming plastic (sourced from ebay) ...
As another commenter pointed out, the vacuum forming plastic is probably the primary concern because the 3D printer was just used to create the molds. The specific type of vacuum plastic isn't mentioned.
Regardless, very neat project.
The SDS for the retainer material in case anyone's interested:
The toxicology section is entirely devoid of data, but I doubt that means anything since the product is purpose-built for dental use in the first place. Safety Data Sheets are more oriented towards immediate and occupational hazards anyways.
Regardless: great job. I'm very impressed by this project -- I love seeing applications of 3d printing. Especially one like this turns an expensive (and slow!) medical procedure into something that can be done easily at home, or cheaply in the office of a trained professional.
So do we over at Additively (your post made me signup after just reading HN for a while). We publish showcases such as the commercial application of the posted aligners on our site - more curated showcases will be published soon.
Edit: That's the commercial 3d printing use case mentioned (Invisalign isn't the only one):
The animation definitely seems the most difficult (and subjective), but also the most cool! Body hacking via computed geometry!
Invisalign (align technology) uses almost the same workflow. Market cap $5.89B.
If you could move the workflow over to something based on WebGL / three.js - you could make this accessible to dentists in developing countries. Could be an awesome open source project.
I think "allowing" it to be used in the US would open yourself up to too much liability though :(
To answer your question, no, "crooked teeth" isn't in the usual list of stereotypes people have about Eastern Europeans.
Maybe amongst an older generation who'd have to go out their way to pay for straightening.
The first step of the process was actually removing two of my bottom teeth; the rest of my teeth have then been adjusted to fill the gaps. It's been a long process (almost two years in), and I'm sick of having these stupid plastic things in my mouth all of the time. But it's definitely been more useful than just for cosmetics (though that's a nice side benefit).
I'm going to send this to my dentist (who's cool enough to appreciate it).
She does that for everybody, along with a number of other practices that do her and (would) her profession great credit.
As to the DIY orthodontic device, this is what I've been waiting for. The day I need a 3D printer haven't quite come, but it's getting close.
I an still awaiting the day I go to the pirate bay, and under Physibles dowload a stl file.
Here's a funny story about dentistry.
I was a thumb sucker. I guess I was nervous? I don't know? I just know I couldn't stop sucking my thumb. It was a horrid habit, and even as a kid I knew it, but just couldn't kick it. I had one baby sitter(the Plumber next door) get so tired of looking at me suck my thumb, while he was watching The Rockford Files; he threatened to cut it off. Well, I inched towards to door quietly, and when I got my hands on the knob, I ran into Donna Oties house, and wouldn't leave her bed. I was 2, or 3? Never forgot that baby sitter. Looking back he was embarrassed, but I literally thought he was going to cut it off. Never quite trusted men since that incident. Even now I find myself trusting women, over men. I think that incident played with my psyche?
O.k. jump to first grade. I'm still sucking my thumb in private. I'm trying to hide it from my parents, but they would catch me. My mom took me to this dentist. His solution was to put two bright stainless bands on my two front incisors. The bands had pin sharp pieces of metal jutting towards my tongue. The theory went--when I put my thumb in my mouth--the needles would prick my thumb making it impossible to suck.
Well, the questions at school never ceased. When one kid found out through my little sister, the bands had tacks on the inside; the jokes were non-stop. I was a strong kid, so the jokes weren't too hurtful, but they still stung. One kid pushed me too far, and I hung him by his feet from the monkey bars. He never talked to me again.
I still had these bands on my teeth in third grade, but I had grinded down the sharp points with my dad's Sears file. I could still suck my thumb, but I knew I needed to stop.
I talked my parents into taking the bands off. I can still see my mother, "But _____, you are going to be buck toothed!"
My father was on my side, and we got them off. Actually, my father bent the pins up a bit so I would be more comfortable eating. He did this early on. I think he knew the anti-thumb sucking pins were wrong, but you didn't want to upset mom back then?
I finally got the pins off in fourth grade. It felt good!
I noticed one lingering side effect of the device; I couldn't smile naturally. Yes, if something was really amusing I would smile, but my hand instinctively went over my mouth. To this day, I can't smile. I can try to smile, but it just comes out looking fake. I'm middle aged now, and I have maybe 10 pictures of myself. I got through high school without my picture being taken. I got through middle shool without my picture taken. My college girlfriend had a picture of me, but she literally had come to tears in order for that Polaroid shot. The DMV, and Costco has my picture--that's it. All these years, I managed to duck, or avoid the camera. Crazy huh?
I was recommended a dentist in town, I showed up to a nice office full of nice people, they looked at my tooth and said they might be able to save it. So far, it was a pretty good experience.
Then it got weird. They took me to a room with a business person who would discuss my "payment options and treatment plan". I got this weird pushy salesman vibe, where they said it would be between ~$900 - ~$1,700 to salvage the tooth. I asked if we could just do an extraction but they only responded with "Oh you don't want to do that!" (playfully) but legitimately not saying it was an option.
So being uninformed and kind of surprised I just went along with it. She had me sign some paper saying I accepted the treatment plan (another red flag) and said she would "waive" my fees for that day (since you know, I'll be back tomorrow with 10x the fees).
Then, the next day I show up for my procedure, and the tooth is cracked too far down for them to salvage it, so the dentist decides he is going to do an extraction.
Ended up with just a $200 bill, and boy was a excited.
They of course tried to set up some kind of maintenance plan where I come in every quarter for checkups, but I declined.
Overall it just feels weird to have such a sales focus feel with something more medical related, and I didn't appreciate being steered away from all of my options, they could have just set me up with an extraction from the beginning. It's my mouth, why can't I decide if I'd save $2,000 to lose a molar.
> I asked if we could just do an extraction but they only responded with "Oh you don't want to do that!" (playfully) but legitimately not saying it was an option.
I think dentists are culturally and by training pre-disposed to keeping your real teeth in your mouth. I've asked different dentists why and they get a hand-wavy, but they all say it's better if your real teeth are in there. This even happened in a scenario where I wanted a tooth removed and an implant put in - they would have made more money saying yes to me, but they pushed me towards other options.
I'm starting to get old, and I have realised that the trick is to keep all your body parts together until everything gives up at once :-)
It's like a shady auto mechanic for people who don't know anything about cars. You go in for an oil change, and they of course identify all sorts of optional repairs, making them sound super scary. "I'm not saying this small oil pan gasket leak will leave you by the side of the road, but you don't want to get behind on preventative maintenance!" Same tactic.
The icing on the cake is when, fast forward a few months, my insurance company sends me notice that they won't cover the visit because the dentist wrote the work up as "orthodontic prep" instead of "standard cleaning" so I need to contact them to get it corrected... and on and on...
I remember when you could go to the dentist, get a cleaning, be out of there in 45 minutes and be down about $100.
Last fall I finally went in for a cleaning after several years of putting it off. At one point I asked the dentist about teeth whitening and he told me that they can do it, but the over-the-counter whitening strips work fine and I should save my money.
Refreshing to hear an answer like that.
I'm going to agree and disagree with this one.
I went a few times to a "dental spa" a couple years ago which was trying to sell me a "night guard" for $900, claiming I was grinding my teeth at night. Their prices for other stuff were pretty high too.
My current dentist pushed me hard to get an electric toothbrush, either from her office or elsewhere. They even gave me a sample brushhead and let me try it out in their office, using some purple pills to show how much cleaner the electric toothbrush made my teeth. Her price actually wasn't that bad compared to Target/Walmart, but I ended up getting a nice Oral-B on Amazon on Black Friday. Guess what? The dentist was right! Now my teeth constantly feel like I just got a polishing at the dentist. I got another Oral-B for my wife on Amazon (it was only $30-35), and she loves it.
Seriously, get an electric toothbrush; it makes a huge difference. You don't need to waste time getting a full polishing when you use one of these daily.
But as for the night guard, my current dentist hasn't tried to sell me one of those. And they recommend twice-a-year visits, which is what my insurance pays for.
It sounds like you need to find a new dentist.
I remembered my own dentist complaining about some swollen gums in my mouth and wanted to surgically treat it because it had gotten too bad. I just told him to deep clean in and lets see in a 6 months. I started regularly flossing and using mouthwash during this time. By 6 months he was surprised that it all recovered with a little cleaning.
Anyway, I took my mother from that place to my own dentist, have them clean her teeth properly and now 10 years later all her teeth are still there any have no pain.
In summary, I don't had trust in most dentists to do what is right for you.
My mom went to the dentist for (the beginnings of) a tooth infection and they tried to sell her a mouth guard that probably cost $1000 or so. There was no evidence at all that she was grinding her teeth.
But they're not without their commercial incentives either. And the waiting times can go into weeks for non-urgent work. Still, the costs are negligible in comparison. We perhaps pay in other ways...
Last time I went to my dentist it was because of a cracked filling (old amalgam), not in any pain, just a bit sensitive so not urgent, waited about four days.
Dentist declared that a crown was necessary but they didn't have a slot just then so would it be alright if I came back after lunch to have it fitted. The crown is manufactured on site using three d imaging and a fancy milling machine.
I don't know how I feel about this post. I don't know if I can consider it a diy project when he has access to equipment beyond the reach of most ppl. if I had access to an orthodontist lab and build my own retainer using their equipment is that considered diy?
Everything else could be pretty easily sourced. Shapeways can 3d print with very good resolution. You can buy a vacuum forming machine from Ebay for 100 bucks for exactly this purpose, or make one yourself with a heat gun, wood, and a shop vac (there's tutorials on youtube).
Still, I've wondered if I'm missing out by not getting custom inserts. It sounds like (at least in your case) there was no major difference?
There's also Superfeet. They're not custom, but there's many options.
Anti-vaxxers are idiots and it is obvious that vaccines don't cause autism (original study was a fraud). The health benefit of vaccines is as undeniable as the lack of correlation to autism.
That said, dental amalgum is a chunk of mercury in your mouth. FDA says it is safe for people over 6yrs old, but I personally will stay away from it for any future dental work.
Amalgam is just plain obsolete, regardless of how safe it may or may not be. So why anyone still uses it, I have no idea; I can only guess they're cheaper than the resin fillings, so they're used for low-income patients, or by shitty (or old-timer) dentists trying to improve their bottom line.
If I have to get more... It'll be resin. The amalgam ones I've got have lasted a long time though, and I don't seem to have any new holes now that I've quit drinking so much soda every day :)
Anyway, the future is promising and the issues could be solved taking into account all the factors.
This doesn't mean that every dentist really cares about this issue but you should search for a professional who cares about this.
Straighter Teeth by Mail - https://news.ycombinator.com/item?id=8998267
Also from a while back:
Invisalign and 3D Printing - https://news.ycombinator.com/item?id=6373936
I went with smilecareclub. They're pretty hands-off but it gets the job done and is a good value
Thanks for the link. It allowed me learn of even cheaper options.
My grandfather used to make dentures, and that casting in the 4th photo looks exactly like the impressions my GF would make. They also used these hinges so they could mate the upper to the lower, so they could adjust any collisions that occurred while opening and closing the mouth.
The rest was just reading freely available docs on how to make castings.
But on a serious note, I had braces, after the were remove a wire was placed behind my teeth to keep them in place. It didn't stick to one of my ceramic teeth I had from an accident in my youth. The wire was removed and after some months my front two teeth were as far apart as ever. Ok, the overbite didn't return but things will move back at least to some degree over time.
As mentioned before, I myself would never just put any plastic material in my mouth with all the bad things known about plasticisers, bpa/bps, etc.
Had two teeth done for under $500 10 years ago.
It's a stop gap until braces are an option financially.
There is not really much tech required. You can simply cut apart the gypsum model tooth by tooth and align it perfectly with wax and add space for you gum. Finally create a mold and use medical grade silicone to make the tooth straightener.
Silicone also allows for more movement and gives you control of upper and lower teeth in relation to each other.
While this is not rocket science there are considerations about jaw alignment that would be difficult for the amature to get right the first time around in any but simple misalignments.
Not sure what I would do if we didn't have a dental school.
When I go there I am always surprised to find people who actually have insurance who still go there despite all the hassle.
First, teeth and their movement is more complicated than it might first seem. You have to think about the entire masticatory apparatus, for example:
• There's more root than crown, how does the root move in relation to the tooth? Root resorption is a common problem in orthodontic treatment.
• Is there / will there be enough bone surrounding the tooth to support the intended movement?
• How will the patient's occlusion (how the teeth fit together) be affected? Part of the Invisalign process is to take a bite registration that shows the upper and lower teeth in relation to each other. This is important, and ignoring it can potentially lead to other complications:
- stress fractures
- supraeruption of opposite tooth
- TMJ pain
• Does the patient display any parafunctional habits that will affect the new tooth positions? For example, do they grind, clench, or have abnormal chewing patterns?
• Many Invisalign techniques require the placement of anchors, holds, and various other structures attached to the teeth themselves. They allow for more complex movement than the insert itself would be able to provide.
• Adjustments are often required mid-treatment. Not everybody’s anatomy and biology is exactly the same, so you have to adjust accordingly.
Now, does every general dentist take this into account 100% of the time? No, but they’re at least trained to recognize these situations and compensate for them.
That said, many simple patients don’t require any more thought than the OP put in. It’s a good thing he looked in a text book and realized that there’s a limit to how much you should try to move a tooth at each step before you’re likely to run into problems. And if you do run into problems — do you think a professional is going to come anywhere near your case?
A few issues I have with his technique:
• Unless he poured his stone model immediately after taking the impression, it’s likely there was a decent loss in accuracy. Alginate is very dimensionally precise, but only for about 30 minutes. The material that most dentists use, PVS, is dimensionally stable for much, much longer (not to mention digital “impressions”).
• Vertical resolution of the 3D print does matter. You might be moving teeth in only two dimensions, you’re applying it over three dimensions.
Again, I think it is awesome that someone gave this a shot, and did a fairly good job as well. I’m all for driving the cost of these types of treatments down, as well as promoting a more hacky/open approach to various treatments. Just know there’s more than meets the eye.
* I decided to go back to tech, there’s too little collaboration in dentistry for me to make a career out of it.
The article says:
"Biofilms have been found to be involved in a wide variety of microbial infections in the body, by one estimate 80% of all infections"
I own one and love it.
One more thing: my hygienist said I didn't have to use the waterpik every day, that it's fine to use it just a few times a week. So I'm trying to use it every other day now. I don't know the pros and cons of using it every day. Are there any long term studies which show that the waterpik is in no way harmful? I don't think so.
PS I didn't floss as a kid, so unfortunately I have tons of dental fillings. I started flossing as an adult, and I'm sure it helped a lot. I still floss once a day.
I'm happy to leave it as a piece on my portfolio :)
I guess this would work better with those with gaps or very mildly crowded teeth.
Often crowded teeth result in pulling teeth to make room.
He might be able to come up with a better or cheaper method then the currently industry standard though ...
I thought about the possibility of DIY Invisalign. My ortho basically did this once and gave me trays that he made in-office.
Obligatory: "orthodontists hate him"
Drinking is not a problem though.