Humans May Be Able to Grow New Teeth Within Just 4 Years
102 points
6 hours ago
| 12 comments
| popularmechanics.com
| HN
throw4847285
3 hours ago
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Popular Mechanics is like Popular Science right? Extremely bullish on new technologies to the degree of taking one study and turning it into a breathless article about how we're 1 year away from flying cars?

Sorry for the cynicism, but I grew up subscribing to Popular Science and I gained a very jaundiced view of this kind of science/technology popularizing

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galkk
1 hour ago
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Unrelated to the growth topic, but related to teeth.

5 or something years ago I read here, on hn, about novamin/biomin and started to buy toothpaste with it.

Since that I had 0 cavities, even if my toothcare routine isn’t the best: most of the time I brush only in evening and when I had severe clinical depression episode I could go weeks without brushing.

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wakawaka28
50 minutes ago
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Do you eat much sugar? Soda or juice? These things make a huge difference. So does age. Young people get cavities easier than somewhat older people.
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abootstrapper
2 hours ago
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I’ve heard this for the last 20 years.
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Fraterkes
5 hours ago
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Confused a bit by the article: it mentions human trials began in september 2024, but also that the trials that might prove it working are yet to start?
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magicalhippo
5 hours ago
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I think it's just poorly written. If you go to the source[1] the trial period was planned from September 2024 to August 2025, and the submission says people are "undergoing" a trial. Perhaps it got delayed, or, more likely IMHO, the trial period is over and they're studying the data so haven't made reached a conclusion yet.

[1]: https://www.kitano-hp.or.jp/info/20240503

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MajesticHobo2
3 hours ago
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It’s a phase 1 clinical trial designed only to assess safety and determine the appropriate dosage. Future trials will focus on efficacy.
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valunord
1 hour ago
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Old news. They were doing this with ultrasound successfully 20 years ago. I know a guy who a tooth back with his own device.
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bumblehean
5 hours ago
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Aren't the shape/size/placement/etc. of human teeth fairly unique across different individuals? At least unique enough to use dental records to identify bodies.

I don't see if mentioned in TFA, but if new human teeth can be grown is it expected that the new ones will just grow in "correctly" to fit a person's mouth?

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throwup238
4 hours ago
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> At least unique enough to use dental records to identify bodies.

Yes but in comparative dental analysis they use ante-mortem dental records to compare with post-mortem remains. It's not like DNA where you can record it once and then use that to match samples decades later in a database. In order to have a high confidence in a match, recent x-rays and records of dental work like fillings, crowns, etc. work best.

And no it is not expected. It's one of the primary challenges with bringing these kinds of drugs to market, as hyperdontia is already relatively common among humans (I had an incisor growing at the roof of my mouth an inch behind my row of teeth). Most successful applications of these tooth regrowth drugs tend to place them near the root of missing teeth hoping that the cellular growth signaling mechanisms are still working.

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clickety_clack
5 hours ago
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Teeth wear quite a bit too, I wonder will new ones have to be pared down to fit.
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RomanPushkin
3 hours ago
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Don't need teeth yet (lol), but curious if anyone is aware of a similar/new ways to restore the enamel?
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petermcneeley
3 hours ago
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eulgro
3 hours ago
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TylerE
4 hours ago
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This is like fusion energy. It's been 4 years away since I've been a child.
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amelius
4 hours ago
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I personally regrew my teeth since I was a child. Granted, once.
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gambiting
3 hours ago
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Fun fact - all of your adult teeth were already there from the start, hiding under(inside?) the gums. We don't "grow" new teeth when the baby teeth fall out - the adult teeth were always there under them.
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rokob
1 hour ago
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This is not true. I’ve seen x-rays of a child’s mouth with clearly no adult teeth visible below the gums. Later I’ve seen X-rays of the same mouth with one or two adult teeth below the gums where baby teeth are about to fall out. The adult teeth are there underneath once the baby teeth fall out but they are not there “from the start”. That isn’t even to mention the size problem.
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dekhn
3 hours ago
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Did they get bigger as you were "Growing up"? Then we grow teeth, you're just being pedantic about whether they're brand new or not.
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Dylan16807
2 hours ago
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It's not pedantic in this context unless you already have a way to set up fresh seed teeth.
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tstrimple
1 hour ago
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It may be fun, but it's not a fact. At birth, you likely have all the tooth buds to grow your primary teeth and maybe your permanent molars. Premolar and canine buds typically form during the first year of life. Second molar buds form around age two. Third molar (wisdom teeth) buds don't begin developing until around age five to six and in some folks they don't grow at all.

I have a condition where my lower front permanent teeth never developed. We weren't sure if any of our kids would have the same issue so we discussed it with the dentist. They couldn't tell us if all the permanent teeth were present or developing because there hadn't been enough time for first xrays to show all of the permanent teeth buds growing. Even at age 3.

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piskov
4 hours ago
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Let’s hope teeth won’t grow in places they shouldn’t.
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kevin_thibedeau
2 hours ago
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Let me introduce you to the teratoma:

https://en.wikipedia.org/wiki/Teratoma

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wellthisisgreat
4 hours ago
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a haircut made of teeth though, hmm
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krater23
3 hours ago
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We all shoult fear the vagina dentata.
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msuniverse2026
4 hours ago
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Scientists regrowing everything except hair. Fuck my life.
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derektank
2 hours ago
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Phase 2 trials on PP405 just completed. They’ll probably begin phase 3 trials sometime next year if you’re looking to enroll.

https://clinicaltrials.gov/study/NCT06393452

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cebert
3 hours ago
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I am hoping for advancements in cartilage growth. I underwent microfracture surgery in my knee and will eventually need a replacement unless we make progress in this field. I would prefer to avoid knee replacement if possible because I enjoy being active. I am hopeful we’re getting close.
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esseph
3 hours ago
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Anecdotal, but I was going in for carpal tunnel work and ran into an older gentleman, probably early 70s, that had just gone through a knee replacement a week earlier. He was walking around on it and said he wasn't really in any pain.

I was amazed.

YMMV.

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cebert
2 hours ago
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I have heard great things about knee replacements. Unfortunately, I’m relatively young (late 30s). If I were to get a replacement now, I’d likely need another one when I’m older. Additionally, I imagine getting an artificial knee replacement would make you no longer a candidate for lab-grown replacements. There is an option already where they can grow your cartilage in a lab, but it’s quite expensive, and my insurance will not cover it.
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xenospn
4 hours ago
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And limbs.
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piskov
4 hours ago
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I would say every tissue: no bones, no organs, eyes, ears, nerves, skin.

Like what can they grow?

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kylecazar
3 hours ago
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Well, I'm personally hoping stem cells pull through for corneal tissue regrowth. I've got significant scarring in one eye. I'd rather not get a donor (cadaver) cornea sewn on if it's avoidable but we'll see.

I think they're making progress.

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janice1999
3 hours ago
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The liver is an exception here - you can grow back a lot of it.
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drdeca
59 minutes ago
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Eh? They can grow skin cultures that are good enough to help burn victims. Not, like, with all the pores and follicles being there, but it is skin…
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zaken
4 hours ago
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finasteride + minoxidil
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janice1999
3 hours ago
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Just keep your mental health in mind - there's growing concern that the link between finasteride and depression has been underestimated [0].

[0] https://www.psychiatrist.com/jcp/analytical-review-depressio...

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b3ing
56 minutes ago
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Finasteride can make you have man-boobs, it’s a known side effect
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piskov
4 hours ago
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Once the follicle is closed/gone, it’s gone.

Minoxidil won’t help grow hair on a patch of bold skin. After that only hair transplantation

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dpark
59 minutes ago
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This isn’t the whole story. Many people have follicles that are dormant. Many people have success regrowing hair on bald spots with minoxidil and/or finasteride.

If you look like Sir Patrick Stewart, yeah, that’s not growing back. A bald spot might fill in with medical treatment though.

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socalgal2
4 hours ago
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I'm sure you're correct. That said, I saw a friend who went bald at 28 get all of his hair back from Minoxidil + finasteride. Maybe his folicles weren't closed/gone but he was bald and a year later, was not.

Apparently there's also now-a-days, Micro-needling, Stem Cell Therapy, Platelet-Rich Plasma, and others. No idea how effective they actually are

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hsuduebc2
4 hours ago
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Well he even had alopecia or he got hair transplant. There is sadly no other option.
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dpark
55 minutes ago
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What does that mean? Alopecia is the general term for hair loss.
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simmerup
4 hours ago
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If you don't have sides that is
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m3kw9
4 hours ago
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Growth rate and how you don’t mess it up before it matures are problems
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zingababba
5 hours ago
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I've been taking vitamin k2 mk4 at 45mg a day for over a year now. My teeth feel gr8. Now I need to get some of this stuff to have super human chompers.
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epicureanideal
5 hours ago
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What changes in your subjective sensation of your teeth with K2?
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giardini
3 hours ago
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This guy's been downvoted badly but he's right - vitamin k2 make your teeth into "superteeth".

I started K2 about 10 years ago. Next dental checkup (about a year too late) the dental tech said my teeth appeared recently-cleaned. This has continued since then. No cavities, little cleaning required other than regular brushing, flossing and taking k2.

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resoluteteeth
37 minutes ago
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IIRC plaque is mineralized by saliva in the same way as tooth enamel, so something that changes saliva in a way that prevents tartar from forming might be reducing the amount of calcium in your saliva in a way that could potentially ultimately not be good for your teeth.
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terribleperson
3 hours ago
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Why mk4 over mk7?
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