Researchers use light to coax stem cells to repair teeth (2014) | Hacker News Reader

Researchers use light to coax stem cells to repair teeth (2014)

seas.harvard.edu

239 pointsmad_dev83 comments

I hope this process becomes part of mainstream dental medicine. Our current dental technology feels backward compared to other fields of medicine

So true. In cases where teeth don't get out as easily as intended, they are sliced, hammered and broken out of your jaw - feels so medieval.

Uhm... do you now how bones get repaired? Only the easiest fractures are allowed to heal themselves. Everything worse than that looks like this: https://teachengineeringprod.blob.core.windows.net/content/c...

Orthopedic surgery is indeed a lot like wood working. Surgeons use saws and drills routinely in the operating room.

Knee replacement isn't much prettier. Here are some links to time stamped surgical highlights

sawing bone [5:55 mark] - https://youtu.be/bGOspdD25Dw?t=355

hammering [11:10 mark] - https://youtu.be/bGOspdD25Dw?t=671

Swinging a hammer like a baseball bat to remove a pin [entire video] - https://www.youtube.com/watch?v=MnBvpSU1Fcc

Dentistry is gruesome but so is surgery, in general.

Made a quick youtube search for latest surgery tech, all I saw was a sewing burning scissors. Cute tech but still barbaric to me. Artery is even more gruesome, plumber. I wish to see organ generation take off somehow.

If you're looking for some interesting surgery tech, check out this fairly simple concept for handling battlefield trauma situations.

https://www.youtube.com/watch?v=BBauDwhGlzg

End part is tough to watch. It's cute tech, and for that context very useful. In civil surgery I want the organic equivalent of this.

Upcoming tech is targeting the WNT pathway to rebuild cartilage.

And this is why I work in IT even though I like power tools

Ever look at how an ACL gets repaired?

Let me guess, (dead) donors?

Either that, or they can take a slice of your own patellar tendon and just graft that on where your ACL used to be.

There are other options inbound rapidly.

Osiris Therapeutics for example has something called Stravix, that they're targeting at tendon repair first. It'll be on the market in November -

"Stravix is a cryopreserved human placental tissue designed to address surgical needs for soft tissue repair"

"Stravix was developed as a pliable allograft cover with tensile strength that is ten times greater than amniotic membranes alone and designed to offer durability, elasticity, and conformability for surgical procedures. In addition, Stravix retains the properties inherent to the native fresh tissue as a result of Osiris’ proprietary cryopreservation process, BioSmart"

They have a bunch of products in the regeneration space. Cartiform for cartilage repair. Menvivo for meniscus repair. etc

Just went through the latter. Would have been so much nicer if there was a way to just regrow it. The attendant swelling in the knee causes the quad to shut down, and atrophy before you get to reactivating it, which precipitates a year-long process of physical therapy before you've got a full stable and strong leg again.

Kind of backward, but also one of the most successful fields of medicine.

Out of curiosity, how do you define success Vs other fields of medicine? It seems like something almost impossible to compare.

I think, most problems can be prevented with effort, and if they still happen, most of them can be fixed with some sort of intervention. Don't think you could say that about many other areas.

The ideal dental treatment would be a dental vaccine(against the mouth bacteria that destroys teeth and harms gums), letting future people not even being aware to dental issues(or maybe just use a monthly/weekly mouthwash). . there was even a startup aiming for that but it stopped due to fda and problems creating a trial.

Hopefully someone like Google finishes that up.

What was the name of the company?

Oragenics.

They are not the only effort. more info at on them and others at:

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

The science: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3708248/

This one seems promising and already has a product on the market:

http://www.curodont.com/en/

Description of their technology:

http://www.curodont.com/en/curolox-technology/

The technology looks beautiful, though I am unable to access the website. Thanks for sharing.

Eh?

Dentistry is one of the few fields of medicine that seems to know exactly how to fix whatever is ailing you and can do so at a cost that can be reasonably borne out-of-pocket without the clowncar of the insurance industry showing up.

I'd say that it's a huge success!

I don't remember where, but I saw dentistry compared to carpentry and the metaphor really stuck.

Take out the old thing, glue in a new thing, spackle, etc.

Hell, dentists even occasionally use brute force to get things to line up better (<-that's an inapt description of braces).

Thats only true if you have simple issues, I've had a molar silently split into 4 pieces (likely) because of a non-perfect filling (one of the only two I have/had). Apart from the non-fix of removing the tooth, there was a tremendous amount of 'umm's and 'maybe's from a competent dentist, and the attempt at root filling and gluing the tooth together ultimately failed.

So now I'm stuck with a molar less, or filing down perfectly healthy teeth to make a bridge, or an implant which might not work because the bone was affected by the previous broken tooth - and molar implants can be problematic in any case - or so I've been told.

Dentistry might not be a dark art anymore, but we appear to be much better at fixing broken bones than broken teeth.

》 Dentistry might not be a dark art anymore, but we appear to be much better at fixing broken bones than broken teeth.

I don't think we are. I'd like to see a real study on this but I would think many more sugeries on bone end with complications that are life altering than dental surgeries, even despite their significantly more intrusive nature (although dental surgeries do always carry risk of nerve damage which can be debilitating).

As a matter of scale, I bet there is a lot more patients for dental work than broken bones requiring surgery. Dentists also see many more patients since the work requires far less time, so I'd imagine these two factors meant they had much more data and practice to work with.

It seems most of the fixing is done by removing old parts and putting on prostheses. When a root is inflamed they just take it out. No antibiotics or whatever. There is not much they can do when your gums recede.

This is definitely an area where I expect to see a lot of progress one day. It looks very hard though.

Last time I saw a dentist I needed 10k worth of work. My current plan involves a trip to Mexico or maybe just dying from blood poisoning.

Several acquaintances of mine living in first world countries resort to going back to their 3rd world countries of origin when serious dental work is needed. So much that it has become a trend and a very common piece of advice.

If this is not a sign of the health care system failing, I do not know what is.

I have been looking for a good dental vacation, any advice?

I had a fantastic experience in Costa Rica. I researched on WhatClinic, TripAdvisor discussions, and various blogs where people talked about their experiences, then contacted a couple places to get a feel for what they were like. I ended up going with one of the most expensive ones there, but it was still a better deal than what my little sister paid for her root canals and crowns after insurance here in the US (she has great benefits as a teacher) - and of course, there was no annual benefit cap to contend with.

I'd definitely recommend going during their rainy season, since hotels and flights are cheaper and you'll spend a ton of time at their office and in your hotel room anyway. If your work won't be too painful and you can afford it, plan the trip to be longer than you actually need so you can build in a little more fun time. Most of the better places have coordinators who are happy to help you figure out where to stay and how best to schedule the trip.

You can send your xrays down ahead of time to get a rough estimate of what's needed, but they'll do a new evaluation when you get there. In my case, they told me that some of what my US-based dentists had recommended was completely unnecessary (and that the treatment plans had likely been more about making money). I needed a few root canals and crowns, but not as many as was recommended here in the US. Similarly, the CR dentist said there was no reason I couldn't keep my 2 remaining wisdom teeth.

I'd recommend staying really, really close to the office you choose. Traffic is pretty awful and the driving down there can be a little scary to those of us who are used to orderly driving. I stayed at the Radisson and went to Meza Dental and it was no more than 5 minutes back and forth, even during rush hour. When your face is numb and you're miserable after a long day at the dentist, that's really nice.

The only thing I think I would have done differently is to pack more of my own food, as hotel food started to get really old and food there can be surprisingly expensive, even at the local Walmart. The hotel employees repeatedly advised against going out after dark (about 5:30-6pm in June) without a large group or local guide, so I ate a lot of room service (which, weirdly enough, was the same price as walking to the hotel restaurants to eat).

On the other hand, this is also a sign of a better functioning market than the rest of health care.

You can actually get a good estimate on the cost of dental work, before it's completed, so you can compare prices. It seems like many procedures have a basic standard, so I would expect similar results from dentists of similar experience with similar facilities. Many dental procedures may be somewhat postponed, so you can shop around, and possibly plan a trip to a different locale. There are no import/export duties or other means of enforcing market segmentation.

I'm not surprised that dental procedures in the US are more expensive -- skilled labor is more expensive, some procedures take several hour and require the dentist, maybe a second dentist, and one or two assistants.

> resort to going back to their 3rd world countries of origin when serious dental work is needed

They also probably wouldn't have to spend money on hotels and have their family to help them with everything, so it's even cheaper

I guess a lot of people are scared to do this because they can't evaluate quality/get good referrals, and of course you're going to get the "low cost clinics" as well as the high level ones.

But in the end the quality of care in 3rd world countries is usually good, especially in major centers

That's a pretty rare and extreme example you're using though. 1% of dental patients need to or do spend more than $2,000 in a given year on dental work. The average person spends less than $500 per year out of pocket on total dental care.

I had a $12k quote in California, $9k in rural southern Illinois...and I ended up going to Costa Rica and getting it done at a fantastic office (clean, modern, upscale, English-speaking, and very friendly) for just a bit over $3k. I got in on Saturday, did a city tour on Sunday, dental work Monday/Tuesday, rainforest excursion Wednesday, final dental work and adjustments Thursday/Friday, flew home on Saturday. Hotel + airfare + food + tours came out to about $1200-1300, and the dental office drove me to and from the airport and all dental appointments.

Perhaps the best and most unexpected thing about it was that the dentist only worked on my teeth during each appointment - none of the patient-hopping my dentists here in the US always did.

Best decision I've made in a while.

How did you find it?

I did research on WhatClinic, TripAdvisor, and a number of random blog posts people made about their experiences abroad. I found several that sounded good, talked to all of them, and went with the one that just felt right.

The dentists there had been trained at UCLA, and their coordinator was a Johns Hopkins alumni, so I felt really comfortable with both their level of education and their command of English (to minimize potential for misunderstandings, since my Spanish is barely enough to understand telenovelas).

> patient-hopping my dentists here in the US always did

Wow, is it a regular thing?

Every time I've ever had work done here in the US, they would do something on my teeth, then switch rooms and work on someone else for a bit, then come back, etc. Sometimes they'd have a hygienist doing something else, but other times I'd just be sitting there waiting. It seems fairly common.

Years ago I switched to brushing with baking soda and salt, and my teeth have basically stopped degenerating. Bar soap is good too, for removing acid-producing bacteria, but I don't like the aftertaste of some soaps.

Gerard Judd is the chemist who recommends brushing with bar soap [1]. It's cheap, readily available, and works better than anything else. And when combined with a second round of brushing with baking soda, my teeth stay squeaky-clean for longer than any toothpaste I've ever used.

[1] http://www.fixyourteeth.org/

Just yesterday my brother & his wife were commenting on how good my 8-year old dog's teeth are. They've never been professionally cleaned. When she was a puppy, we fed her raw chicken with bones. When she got to be full sized this was too expensive, so she now she eats dog food. I think the main reason she has such good teeth now is because she had adequate calcium and other nutrients when her teeth were forming.

Does your veterinarian not recommend having her teeth professionally cleaned?

Humans who have perfectly healthy and well taken care of teeth still go to the dentist, and for dogs it is no different. You should still be getting her once a year!

There are more issues than not which could be happening that are not visible to the untrained eye.

She got her puppy vaccinations, but didn't go to the vet for a very long time after that - it wasn't in my budget, and wasn't necessary. My dad needed a dog, so he takes care of her now, and I'm sure he'd have her teeth cleaned if the new vet had recommended it.

Dogs have a much shorter lifespan so tooth decay is normally only really a problem if they eat processed foods.

The veterinary business has a huge problem with dishonest upselling and recommending unnecessary treatments. "A vet recommends X" doesn't care the same kind of weight as "a doctor recommends X", and won't until the veterinary profession gets real ethics standards imposed.

You really should not feed chicken bones to a day. The fragments can be very sharp and cause medical problems.

http://www.vetblog.net/2013/07/dog.swallowed.chicken.bone.pr...

http://keepthetailwagging.com/dont-panic-when-a-dog-eats-a-c...

That only applies to cooked chicken bones, not raw ones.

She did fine with the bones when she was a puppy. In theory, raw chicken bones shatter less than cooked chicken bones.

As I said elsewhere, she now eats regular dog food. When I'm visiting, I'll cut the cartilage off the end of a cooked chicken bone and give that to her. Sometimes she still helps herself to whatever bones she finds, and she hasn't had any problems.

Size might be a factor - she is about 75 pounds.

My dad's previous dog ate corn cobs. After years of this, a corn cob got stuck in his throat, leading to a big vet bill, so our dogs don't get corn cobs anymore.

This is a misconception largely born from thanksgiving and christmas time warnings. The issue is cooked bones from anything, not just poultry. Cooked cattle or pig or goat or sheep or lizard or whatever all post the exact same hazard. In much searching, I was not able to find any credible evidence that raw bones pose a threat.

Chickens don’t have bones anymore - they grow so fast that there is not time for the bones to mineralise. My brother and I used to always break the wishbone with each other whenever we had a roast chicken when we were kids. I tried about a year ago to do this with my kids and it was impossible.

Every chicken I've ever cooked, including the one last night had bones. We're talking bones that take a lot of force to break.

They have pseudo-bones (basically just cartilage with minor mineralisation). These “bones” are nothing like they were like 40 years ago. This cartilage is of course tough, but try cracking a wishbone of a modern meat chicken - it just bends rather than snaps.

Interestingly the growth rate of modern meat chickens is limited to bone mineralisation rate. If you breed a chicken with faster growth rates (which you can do) they end up with broken legs as the bone can’t support the weight of the bird [1].

1. http://japr.oxfordjournals.org/content/16/1/138.full.pdf

Raw chicken bones are "chewy" and not brittle. Its cooked/dried bones that you shouldn't feed to dogs.

Cavities are formed when sugar reacts with bacteria in the mouth. Normal dog food has very little sugar in it, especially if you avoid feeding your dog human food. (This is why your dog prefers human food. It's generally full of tasty sugar.)

Most dogs do have calculus in their mouth even if there is not active decay. There is also subgingival calculus (below the gum line, not visible to the human eye). Taking your dog to annual vet visits is important because they can help diagnose dental issues.

>Cavities are formed when sugar reacts with bacteria in the mouth. Normal dog food has very little sugar in it, especially if you avoid feeding your dog human food

Lots of dog foods contains sugars, and even more contain a ton of more complex carbs, which the bacteria do still feed on. This is why species appropriate raw fed dogs don't have calculus, they don't eat carbs.

> Cavities are formed when sugar reacts with bacteria in the mouth.

The link provided argues otherwise:

"Bacteria cannot damage the enamel (calcium hydroxy phosphate). There is no such thing as decay of the enamel since bacteria require carbon and hydrogen to live. Billions of human and animal remains show teeth and bones are resistant to earth-bound organisms."

and

"acids alone eat the enamel..."

- http://www.fixyourteeth.org/Gerard-Judd/summary-teeth.htm

And the bacteria eat sugar and produce acid. That whole site is a load of nonsense

Do you have good sources against his general claims? Should I try out bar soap? I'd really like to get to the bottom of this.

After I read your comment, it occurred to me to read about bacterial films. This is the Wikipedia article: https://en.m.wikipedia.org/wiki/Biofilm

If you don't mind spending a few dollars, flavored tooth soaps are carried by most natural food stores.

You didn't correctly read what I wrote.

This some time cube level nonsense.

I'm pretty sure it's a prank to get gullible people to try brushing their teeth with bar soap.

cube level?

Time Cube: http://timecube.2enp.com/

Are you telling me you don't enjoy the taste of Irish Spring??

Be careful with baking soda. It is abrasive to emanel. Use sparingly and allow emanel to regenerate.

Straight baking soda is actually the least abrasive option on the lists. Here's a link: http://www.sheltondentistry.com/patient-information/toothpas...

If one is concerned about rubbing their teeth away, baking soda and salt will rapidly dissolve in the saliva.

(2014)

Any updates on this since then?

If you like this, you should really read about another new technology which regrows dental tissue using sound: http://www.colgate.com/en/us/oc/oral-health/cosmetic-dentist...

This is kinda old. But I was surprised to know that such an advancement in stem-cell research has been made.

Sigh, I hope more comes of it. This is the first time I've ever heard of it.

What kind of regulations does a treatment like this have coming it's way?

We've "cured" cavities quite a few times via fighting the primary cavity causing bacteria S. Mutans with techniques ranging from phages, to a vaccine, to introducing a crippled version of the bacteria in a semi-sterilized mouth. Wondered what happened to all of those options?

Probably gone to Cuba with the cure for lung cancer.

[1] suggests that it's a combination of it being at least mildly hard, and there being insufficient fiscal incentive to develop it.

It seems several vendors have realized solutions in varying stages of human trials, without getting to the "commercial" stage (yet):

- "CaroRx" is entirely not mentioned on the owning company's products list [2]

- The list of authors on the antibiotic study from the Chinese Academy of Sciences don't seem to have published any other studies on this since the 2013 one [3]

- Oragenics seems to have just gotten a patent on a new form of their one-off replacement bacteria [4], but that's not nearly the same thing as human trial approval

- The US military's gum for mitigating issues with dental neglect that happen in combat seems to currently be attempting to get licensed to non-military vendors for civilian use. [5] [6]

[1] - https://en.wikipedia.org/wiki/Caries_vaccine

[2] - www.planetbiotechnology.com/products.html

[3] - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3708248/

[4] - http://www.oragenics.com/news-media/press-releases/detail/35...

[5] - http://www.newyorker.com/tech/elements/zero-dark-cavity

[6] - http://techlinkcenter.org/summaries/antimicrobial-peptide-an...

Where can I sign up for participation in medical trials on this?

Any news on gum disease?

First the article says: "drill holes in their molars, treat the tooth pulp that contains adult dental stem cells with low-dose laser treatments, applied temporary caps"

Then it says: "Dave and his team have added an innovative, noninvasive and remarkably simple but powerful tool"

Yeah, okay, if you read Wiktionary it defines "noninvasive" as "not requiring an incision". So by that strict definition it's true. Drilling holes is totally different than "an incision". Right?

I realize that this has "a host of applications", some of which truly are noninvasive. It's just that this particular application was anything but noninvasive, IMO.

Seems you skimmed the article.

The first part you quoted was explaining the prior art done by the lead author -- giving rodents (not humans) damaged tooth.

The innovative procedure on humans will use lasers to trigger restoration of the damaged teeth.

Seems you skimmed the article.

I did not skim the article. Show me where it clearly says that they have an "innovative procedure" that noninvasively triggers human dentin stem cells.

They alluded to other noninvasive uses, but this wasn't one of them.

I assumed the drilling was to simulate tooth decay and to remove something to be grown back as a trial, did I read it incorrectly?

did I read it incorrectly?

The way I interpreted it, they drilled into teeth from the top in order to reach the "adult dental stem cells" (see item #3 here which is dentin: https://en.wikipedia.org/wiki/Human_tooth#/media/File:Cross_...). The dentin stem cells are probably contained within the dentin?

They wanted to stimulate the dentin stem cells with the laser light, but there is no way to reach dentin without drilling through the outer tooth enamel. They're not simulating tooth decay, they simply need to get to the dentin.

Their conclusion was that this laser treatment "triggered the enhanced dentin formation".

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