Microrobots can brush and floss teeth in a proof-of-concept study | Hacker News Reader

Microrobots can brush and floss teeth in a proof-of-concept study

penntoday.upenn.edu

287 pointsgeox217 comments

I am really tired of the hijacking of concepts like "bot" or "robot" to mean "small magnetic particles which form a virtual scrubbing brush, and we make them move by rotating a magnetic field"

these are lumps of magnetite. they have no autonomous element, no programming, no decision logic, no ALU, no FPGA, no WiFi, no data, no analogue computer, nothing.

Its not smart dust: its dumb dust and a rotating magnet. Its not a bot.

Thanks for the explanation, as I was really wondering what the robotic aspect is in this.

I'd like to second this and just say, please leave these kind of posts on reddit. There's nothing of interest or relevance to technology here.

I come to this site for substantive links, not clickbait.

This is very interesting and has a lot of potential, especially for people who struggle to brush their teeth, but I think there's another future where brushing and flossing largely become obsolete. If we could develop a more effective mouthwash tailored to restoring each persons oral microbiome we could likely reduce the need for brushing and flossing and instead replace it with a daily mouth rinse that clears out food debris and selectively targets pathogenic bacteria while promoting healthy species.

I'm a bit biased, though, because this is something we're working towards building at my company down the road.

Wouldn't the mouthwash need abrasive particles as well? Part of why Listerine doesn't replace brushing and flossing is because it has a much smaller mechanical component in the washing process. The physical rubbing of bristles and wire through and around the teeth creates the physical abrasion that is necessary to remove large films of plaque.

I imagine without any sort of abrasive, the liquid would need to be dangerously strong to remove tougher plaque.

Yes. Talk to your dental hygienist and they will confirm this. Mine told me a story recently of when she was in school they were graded on how little plaque they had on their teeth. So her and all her friends did everything they could. New toothbrushes, flossing, the metal scrapers, and helping each other. No one removed everything and I guess that's the point of the lesson. Plaque builds up quickly and over time. What harms teeth and gums is far more than microbes.

But that also seems like where nanobots would come in. If you could have a mouth wash that had nanobots that would perform that abrasive scrubbing and then decay (and not leave byproducts) then it would help and could replace brushing and flossing. But definitely mouthwash is nowhere near the effectiveness of brushing nor flossing. Would be a cool future, but I suspect we're still a long way from that.

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Preventing plaque formation avoids the need to remove it.

Actually accomplishing that seems unlikely, but not impossible.

There has been work done is creating GM S. mutans that don't produce biofilms, and that would replace your native S. mutans. It could be done by just brushing your teeth with a toothbrush treated with the bacteria so it would cost pennies per treatment.

That’s a long way from actually replacing brushing and flossing.

For one thing, streptococcus sobrinus is more closely associated with cavity formation than streptococcus mutans. But more importantly these biofilms are a significant evolutionary advantage so this replacement is an unstable situation. Some positive benefits are likely, just don’t assume it can work alone.

Biofilms are an evolutionary advantage for the bacteria, not the host. Biofilms make the colony much, much harder to kill. How advantageous can it be to the host anyways, if 4 out of 5 dentists recommends obliterating it 2-3x a day?

This is trying to replace the bacteria population not the host.

It’s like trying to stop drug use by busting drug dealers. As long as the niche exists a city can’t stop and say we caught all the bad guys problem is solved.

That analogy doesn't hold - the niche is still being filled. A better equivalent would be the synthol drink from Star Trek - it's the same bacteria, but modified to remove the most problematic part.

It’s the same relationship:

We might call it the same species, but the relevant chararistic changed is detrimental to a [human] host but beneficial to the [bacteria] parasite.

We might call it the same species, but the relevant chararistic changed is detrimental to a [city] host but beneficial to the [drug dealer] parasite.

Consider if you removed all the wings on misquotes in a city. That would be useful on day 1, but not going to do anything a year from now. It’s the same species, but missing a very useful trait means it’s getting outcompeted.

> Consider if you removed all the wings on misquotes in a city.

That's not an accurate analogy for biofilms. Even if it was, I noted below that the mechanical action of brushing your teeth annihilates any biofilm (i.e. plaque) that has built up. That being the case, how do you explain the fact that people who brush their teeth are not suffering from infection from advantageous disease?

If you wipe out your gut flora, there are health serious implications. All evidence seems to point to the opposite case in your mouth.

I think you may have confused me with the other poster: https://news.ycombinator.com/item?id=32007812

Anyway brushing your teeth doesn't sterilize your mouth or even disrupt your mouth flora that much.

But brushing and flossing does do many things. It helps your spit/toothpaste to remineralize your teeth repairing microscopic damage, removes leftover buts of food, and generally makes your mouth noticeably less hospitable to bacteria alongside reducing biofilms.

As soon as you stop bushing things start getting worse, but that's why it's a daily activity.

I'm not confusing you for anyone - I explicitly said I was making the same point. You are arguing that genetically modifying mouth bacteria to not-form biofilms could be detrimental to health, and I pointing out that if that was true, we would already see those affects from daily brushing. You seem to agree that brushing removes biofilms, so I guess I don't understand your original hypothesis.

> modifying mouth bacteria to not-form biofilms could be detrimental to health

I said it would be detrimental to the bacteria’s health not the persons.

Not brushing would be bad for a persons health, and this would still be true after treatment with modified bacteria.

They may indirectly be an advantage for the host because if the bacteria aren't competitive they will get replaced by bacteria that are. The devil you know...

I hear you, but again - the strongly recommended medical advice is to brush your teeth twice a day to remove bacteria before they can form a biofilm, so if that was true, you would expect to see people who brush their teeth have worse problems from advantageous bacteria.

For sure, I don't think it would replace as much as supplement. And obviously your mouth flora can change based on any number of factors, so it might have to be something like a special toothpaste since it likely wouldn't be a one-time treatment.

Plus, I would imagine it would be a hell of a lot cheaper than nanobots once the bacteria strains are developed and tested.

A keto diet without sugar or starch should prevent most plaque formation, shouldn't it?

No, a balanced keto diet might be moderately better than a normal diet in terms of plaque, but even wild cats living on a nearly 100% meat diet still get dental plaque.

reminded - our cat was flossing his teeth using the corn broom that we had. He would press the broom with his paw and would byte a fiber close to the broom root and would move his head away so that the fiber would be flossing the teeth, and he would repeat it multiple times flossing different teeth. Still had perfect teeth at 13 when the cancer took him.

This doesn't sound possible. A big component of oral hygiene is removing the relatively large chunks of food that are hiding invisibly between your teeth. If you leave them there, they will rot and smell bad and cause other issues like infections. You need a physical object like the bristles of a tooth brush and/or floss to physically dislodge the bits of food. That's why every culture developed some way to clean their teeth.

GP did say "replace" but they also said "reduce" so I'm thinking they meant replace the majority of brushing, but probably not all of it. If they had an effective way of removing lettuce from teeth chemically, I'd be afraid of side effects.

Yes, thank you for catching this. As the comment above pointed out there will still be a need for removing larger food particles and hard to reach areas, but ideally with the addition of the mouthwash/intervention I'm mentioning we could drastically reduce the incidence of oral disease.

It doesn't seem far-fetched to imagine a chewing-gum-like substance which achieves this.

Like a dishwasher but for teeth?

Some people rarely brush their teeth and never get cavities. Some people brush thrice daily and floss and still get cavities and need root canals.

The working theory is we could all be in the first group with the right bacteria in our mouth.

That's it exactly. Some beneficial species play an active role in suppressing the pathogenic species (those that release acid or cause gum disease) and have other benefits including helping us break down dietary nitrate into nitric oxide, which is critical for heart/brain health.

My company tests/researches the oral microbiome and we're starting to discover the signatures of what puts people in one group vs. the other, with hopes of helping develop more personalized approaches down the road, but for now helping people understand what will work best for them.

Here's my company for anyone who is interested in learning more: https://www.bristlehealth.com/

What's preventing you from shipping to Canada, and any plans to expand outside the US in the future?

This is very cool.

What’s your take on xytiol gums? Think they’re effective in changing our oral microdiome for the better?

I'm also curious about this, but unfortunately I think that's where it will end for me in practice. Even if xylitol is effective, it seems the xylitol you'll get in any products (at least in the US) is going to be industrial byproduct from sketchy unregulated sources, just with greenwashed packaging. If there is a gum or rinse out there that is transparent and credible about their source of xylitol, and it's a source you can trust with your health, I'd love to try it out.

(I admit that you can probably say the same thing about any toothpaste you can buy in the US. But those have at least some additional benefits from regulation.)

The initial data on xylitol looks promising for reducing cavities! Particularly for stimulating saliva production (dry mouth is a large contributor to cavities risk) and as a sugar substitute that cavity-causing species can't digest into acid. I'm excited to see more research come out and compare it with our data.

Could it also be about the level of salivation in general, since saliva also helps kill some bacteria and keep the mouth cleaner (relatively)?

Definitely! Saliva is our best natural defense against cavities (and harmful bacteria), so we always recommend people who have struggled with cavities or dry mouth to consider options for increasing their saliva production, like chewing sugar-free or xylitol gum.

Those two groups are likely differentiated on diet. For starters, diet can overload your mouth with complex and simple sugars, but diet can also determine the bacterial makeup of your mouth.

No idea where it eventually led, but I read about work done back in the 80s to vaccinate against the bacteria that cause tooth decay. That suggests that some people might have natural immunity to them.

It's also pretty likely that there is variation in enamel formation and hardness (driven by genetic differences).

I was referring to something more along the lines of what the above comment mentions (rebalancing with beneficial bacteria), but there are companies working on something like a dishwasher for teeth, one example is below:

https://freshhealth.com/

Do you have much hope that dentists would cooperate in studying this, possibly disrupting the drill-fill-bill model that supplies their income?

Why not just continue the work that's already been done in developing GM strains of S. mutans that don't produce biofilms?

We think this work is fascinating, but S. mutans isn’t the only species in the oral cavity capable of developing biofilms (nor is it the only cavity-causing species). I think this could be a great first step, but we’re currently more focused on how to cultivate our healthy species than bioengineer alternatives (a question of competencies and priorities)

What is your company? And have you identified anything you could recommend to help “cultivate our healthy species”?

My company is Bristle (bristlehealth.com), and we've found several things that look to cultivate healthy species so far.

Hygiene plays a huge role (of course), but outside of that diet plays a large role. Cheese/dairy has been found to reduce cavity incidence, high fiber vegetables stimulate saliva production and neutralize acid, and a nitrate rich diet has been shown to increase levels of beneficial bacteria (called nitrate reducing species) that help us produce nitric oxide [2].

There's some exciting research on probiotics [3] as potential interventions as well, particularly if used with a proper hygiene regimen.

[1]https://www.bristlehealth.com/post/how-our-diets-can-affect-...

[2]https://pubmed.ncbi.nlm.nih.gov/33742692/

[3]https://www.bristlehealth.com/post/a-guide-to-oral-probiotic...

Interesting. Could you share a bit more, without revealing stuff that you don't want to share in public?

ProTip: I went from rarely flossing to basically every day with "this one weird trick": I now floss my teeth in the shower. I like staying in the shower a little longer, so the 2 minutes went from chore to luxury. And the amount of food I remove on a daily basis is astonishing!

I started using those floss picks with the handles. I resisted the idea for ages since it seemed wasteful but I really hate wrapping the floss around my fingers. The picks make it so much easier, you can get them made of non petrochemical plastics (PLA) as well making them slightly less bad for the environment.

I also switched to the picks with handles as part of that change. I used to do the "tie floss into a loop" trick, but it was kind of a pain in the butt to do that. So part of lowering the barrier was going with picks. I also hate the waste, but figure it's worth it for the tooth longevity.

Your comment reminded me of https://www.youtube.com/watch?v=NMQTg4Y0YT0

I get the comedy but now I'm wondering why he ordered a pair of chinos if he doesn't plan to get out of the shower.

Same. It is a way to incorporate it into the daily routine.

Also, I tie my floss into a big loop. I can tension it with my whole hand while still using individual fingers to get it where I need it.

Takes practice to get a quick easy knot that doesn't slip, but now it is like tying shoelaces - automatic and quick.

I honestly think "floss loops" is the next "sliced bread".

This is actually genius, I'm gonna start doing this as well. Thank you for the great idea.

You can brush your teeth in the shower too.

Done and done! That's another part of that plan, I floss and then brush.

Isn't the science on flossing not showing any benefit?

Edit: looked it up. No solid scientific evidence flossing helps.

Bro, you don't need a paper to demonstrate the benefit of flossing.

Just get right in there at the back with some decent floss (Oral B Satin Tape is good), and taste the rotten, disgusting food you remove. That's what the people around you are smelling every day when you exhale.

Don't be an ass, don't imply my breath smells. Be better than that.

If you don't floss, I can promise you that your breath smells.

Maybe not bad, but people notice it if you're in close quarters.

Have you done a scientific review, or just talking out of your ass?

You need a scientific study to know that rotting food smells bad?

Sure:

> Our study confirmed that use of dental floss was associated with lower odds of having oral malodor after controlling for other factors. This agrees with the findings reported recently by AlSadhan [15] who demonstrated statistically significant relationship between self-reported halitosis and use of dental floss. Faveri et al.[32] evaluated the effect of interdental flossing on oral malodor and found that there was a significantly lower concentration of sulfur compounds after using dental floss.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5727733/

> You need a scientific study to know that rotting food smells bad?

Stop behaving like a jerk, please. Be better than that here on HN. That's just a straw man. If you remove all food by normal brushing (which most scientific evidence points towards), your argument doesn't even make sense. As there is no food left.

Excuse me? I'm being a jerk?

I guess we can just leave it there then.

Have a nice day :)

Talking out of their ass. It is a simple fact of life some folks never floss and basically don't brush while smelling equally minty to folks that floss and brush twice per day. The easiest way to figure out this is true is thinking about how few people floss (you can ask your dentist, most people don't) and how many people have bad smelling breath (easy to smell when you're in public transport).

There is surprisingly little peer reviewed data on flossing, but we ran our own study on how flossing impacts the oral microbiome (surveying our users) and found that flossing incidence is correlated with reduced levels of gum disease, bad breath, and cavities related bacterial species:

https://www.bristlehealth.com/post/bristle-research-the-effe...

That's what I thought. Then I tried not flossing, and my gums got unhealthy and started bleeding a lot in like two weeks. My teeth aren't unusual; I wouldn't expect to be that much of an outlier; so not sure what was going on in those studies that I also had heard about.

I don't know about scientific evidence, but I do know that personally, for my teeth, when I went from infrequent flossing to frequent: My dental visit time went down, he spent less time scraping off plaque, and my gum pocket readings went down from 2-4 to 1-3. I also know that basically every day I'm pulling an amazing amount of food out from between my teeth, which if I didn't floss would sit there and build up plaque.

Only floss the teeth you want to keep

I find it strange that there is so little innovation in the field of everyday tooth care. Particularly the inefficiency of brushing one tooth at a time. I like the idea of https://blizzbrush.com/, has anyone tried it? It's a bit suspicious that the single-pack is "sold out", but the 5 and 10-packs are not.

I think it's because incumbents in the space have played a huge role in preventing adoption of new technologies that actually prevent disease. Dentists make money not from preventing disease, but from performing procedures when disease has already progressed to the point of no return.

Cavities and gum disease are bacterial infections that are completely preventable. I feel the need to plug what we've been building at https://www.bristlehealth.com/. We've built an at-home test that leverages the microbes in the mouth to detect disease, and provide actionable and personalized recommendations that can reduce your risk of gum disease, cavities and persistent bad breath.

> Dentists make money not from preventing disease, but from performing procedures when disease has already progressed to the point of no return.

I find that hard to believe as dentists wouldn't be the group of people I'd imagine developing those new ideas and products. How would that work?

Nobody wants to go to the dentist until it’s too late, because it’s so expensive nor covered by health insurance.

Even if it’s not intentional, dentists aren’t R&D specialists. They’re a service, at a premium price, whose livelihood depends on people going for treatments.

What lever do they have to prevent new products from being developed that help people take care of their teeth?

They don’t have one. There is no lever. This is conspiracy theory nonsense, but even if there was a lever they wouldn’t need to pull it.

I move in social circles with a lot of people from the dental care industry and I can tell you that no one is worried about running out of treatment opportunities.

I’ve met hundreds of dentists over the last 18 years and they all spend their days asking patients to brush and floss. It’s a simple thing, it's pretty cheap, and prevents almost all oral diseases regardless of diet or genetics. It's easier than changing your diet. It's a LOT easier than changing your mouth biome. It's practically a miracle cure when done regularly with decent technique.

And… the vast majority of people simply don’t brush and floss like they should. I'd guess that the group that does is about the same size as those who actually get enough exercise, which is about 23.2% in America[1]. People consume mind-boggling amounts of refined sugars and generally don’t take care of their teeth.

There is no sinister cabal keeping people in cavities and gum disease because, it’s simply not needed.

[1]https://www.cdc.gov/nchs/fastats/exercise.htm

The lever is the lack of funding and motivation brought about by the previous factors. It’s not an individual choice, rather a medical industry wide systemic issue.

This seems a pretty likely reason, especially when you see this sort of thing even for regular medicine: https://www.cnbc.com/2018/04/11/goldman-asks-is-curing-patie...

Dental is so much more profit oriented that it would be actually insane to think they're devoting R&D towards something like preventative medicine.

If you are in the US, like me, you might not be aware of Novamin toothpastes. They are available in other countries. It is my understanding that it can enclose dentin tubules exposed by enamel loss.

This article provides some background:

https://medium.com/@ravenstine/the-curious-history-of-novami...

I was considering this recently based on a thread from last week:

https://news.ycombinator.com/item?id=31954800

Do you have a reliable source to purchase? I've no interest in purchasing via Amazon, wouldn't feel comfortable trusting the content.

I've had bad teeth since adulthood, partly due to a medication changing the pH of my saliva, and partly due to a Pepsi addiction.

I swear by the Novamin tooth paste, my life has gone from always having small aches and icing in my teeth to my teeth hardly being a factor anymore.

CPP-ACFP (a.k.a. Recaldent) is better than Novamin, at least according to one study:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6006878/

I have, after years of deliberatng, decided to use an electric toothbrush. Its been 2 years and I want to know what I should be expecting. Maybe I am sleepy when I a brushing so I don't notice but asking still.

Novamin sounds interesting. Its available here on amazon so I might splurge on it but again, what I am to expect out of it as opposed to regular Colgate ?

For me it removed that icy feeling.

been doing nano-hydroxyapatite for the same reason. I use stannous fluoride based toothpaste in the morning and nhdpa at night before bed.

Isn’t Biomin the same thing

There is quite some innovation, but consumers are slow to adopt IMO.

Last year, my dentist warned me I have quite severe receded gums. This was due to me pushing my toothbrush too hard.

So, after doing some research I bought an ultrasonic toothbrush. These have a static head (it does not oscillate/rotate) which emits ultrasonic waves to clean your teeth. Same principle of an ultrasonic parts cleaner. The head is still a traditional brush, though very soft. The brush is used to transfer the sound waves, you do not use it to 'scrub' your teeth. There is not friction involved.

From my experience, I can highly recommend an ultrasonic toothbrush. It takes some time to get used to, but personally, I will never go back to a traditional 'friction' type brush (manual or electric).

The model I have is the Silkin' ToothWave. Prices have come down significantly since I bought mine (I paid >€200 IIRC, now they are ~€90).

Note that some vendors sell traditional 'friction type' oscillating electronic toothbrushes with ultrasonic as a feature. In my opinion, these do not offer much benefit, it is better to go for a fully ultrasonic model.

Where do you get them for 90? I only see them at 190 in Germany.

https://www.idealo.de/preisvergleich/ProductCategory/3233.ht...

You can get it here for 99 euro in the Netherlands: https://www.bol.com/nl/nl/p/silk-n-toothwave-elektrische-tan...

https://silkn.eu/toothwave

This site has them for 250 euro. I assume that's the cheapest for a US customer that is ordering?

Oh, they don't ship to the US. How do US customers buy this?

They have a US page here: https://silkn.com/products/toothwave-1

I see thanks. How do they compare with the much cheaper phillips sonicare toothbrushes is the question.

Interesting. I've also had success using a Sonicare but always moving from the gums to the tooth (instead of along the gumline as the manual suggests).

Are these ultrasonic toothbrushes actually using ultrasonic waves? I have an expensive sonicare toothbrush and a cheap noname $10 "sonic" toothbrush from the supermarket and can't really tell the difference between both. Both feel like a standard toothbrush with a phone vibrating motor put inside.

FYI, at least one review of multiple studies have shown that ultrasonic tooth brushes are no better than sonic toothbrushes.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7175112/

Looks like 250 EUR on their website?

Looks like that pricing has not been updated for a while. I paid something like 200 euros, that was about a year ago. Most online retailers in my country now list them for less than 100 euros.

Weird. In Dutch (https://silkn.nl/toothwave-black) it’s €119.

In English (both EU and GB), French, Spanish, and German ( e.g. https://silkn.eu/toothwave-black) it’s €249.

Huh, interesting!

How often do you change brush heads? They are quite expensive at $15/piece.

I have used it for about a year now, and haven't need to change them yet. It comes with 2 brushes in the box, and I'm still using the first brush, it is not showing any signs of wear.

The main thing is that you do not need to brush with any friction. You just move the brush gently over your teeth, so they barely wear.

For me this is also why I like it. With traditional hand brushes, I'd wear them out in 3 months or so. In hindsight this was a clear indicator that I was pushing way to hard on them.

Is this different technology? I have one of these but haven't used it in years.

https://techcrunch.com/2010/07/09/solar-powered-toothbrush/

I'm not sure if I am comfortable with the idea of sending ultrasonic waves into the brain every day ...

This isn't a totally crazy concern: focused ultrasound (fUS) can be used to modulate brain activity non-invasively (or even make therapeutic lesions).

However, a toothbrush is almost certainly not going to do that. The skull's impedance is way too high for the dinky transducer in your toothbrush and even if it weren't, you need to do all sorts of clever corrections to focus the ultrasound on a particular spot.

Maybe it prevents Alzheimer’s?

This sponge you put in your mouth made me think for the first time about how much bacteria is potentially on a normal toothbrush.

I'm betting this product is even less hygienic since it's a sponge instead of only bristles.

Why not leave your toothbrush in hydrogen peroxide overnight?

Good idea, it's just I never thought twice about the cleanliness of a toothbrush. I guess it's been ingrained in me to think it's normal to run a toothbrush under water to "clean" it.

I remember a myth busters episode where they demonstrated that toothbrushes left in open air will easily get fecal matter on the brush hairs due to aerosolized poop from when you flush an open lid toilet. Definitely a great conversation ice-breaker.

   After confirming that a toilet flush does emit an aerosol spray, Adam builds a rack to hold 44 toothbrushes at various distances from the toilet in the shop, as well as two controls kept in the office. Each day, Adam and Jamie exposed the brushes to toothpaste and rinsed with distilled water, with brushing with a pair kept right above the toilet bowl. Fecal coliforms were indeed found on all the test brushes, including the control ones, but none at a level high enough to be dangerous. A microbiologist from UCSF confirmed that such coliforms were impossible to completely avoid, and that there was no significant difference in the number of bacteria based on where the toothbrushes were placed in respect to the toilet bowl. This surprising result prompts the narrator to proclaim "Some myths are best left unanswered!"

Since the controls were kept in his office... it does seem like it's impossible to avoid fecal coliform bacteria.

If that's the case, I'm going to convince myself that I'm doing my immune system some good exposing it to such horrors in minute quantities..

Are toilets in the bathroom common in your country ? Here, in France, they are a separate room - which also helps with multiple simultaneous uses.

I've never seen a bathroom without a toilet in it in France. Is it regional? Or could it be a matter of the types of lodgings like flats v.s homes?

I've seen the splitinh in actual house in the Netherlands and Belgium so maybe some Northern France houses also split?

They're common in North America, maybe because having bigger houses and therefore having multiple bathrooms is also more common.

It's considered luxury in the united states to have the toilet enclosed in a smaller room inside the bathroom. Most American cities are expensive enough per sqft that it's certainly not standard to have a larger bathroom capable of enclosed toilets.

Even growing up in a lower cost of living area, I would associate a master bathroom with an enclosed toilet room as a luxury or wealthy amenity.

Good to know. I've always wondered why my bathroom has a separate little closet-sized room with a toilet. I always thought it was worse because you can't wash your hands until after you've touched the flusher handle and the door knob. Of course any reasonable person with two hands will use separate hands, but it's just weird to me.

Additionally, there was a towel rack in that room. I took it down because, again, it makes no sense. Why would anyone need a towel in the toilet room?

It has bacteria that was already in your mouth right? Unless the bacteria multiplies and grows outside of your mouth I don’t think it’s much of an issue.

It isn't but some people want things 100% germ free so they'll jump through hoops to sanitize. I wash my hands, rinse the head of the brush, and use a peas sized bit of toothpaste, brush a couple minutes. Twice a day. Electric toothbrushes are too complicated and annoying. Toss after three months. You can also use a stannous fluoride based tooth paste as well as it has germ fighting capabilities over and above regular fluoride based toothpaste if that's your jam. I use boka which is a nano-hydroxyapatite based toothpaste like is commonly used in japan. No cavities in the past decade and hygenist always complements me on making her job easy. I use stannous fluoride in the mornings and n-hdap at night before I go to bed.

You are supposed to change the brush every few months precisely for this reason.

I thought it was because the hairs on the brush get 'blunt' from erosion on your teeth. The 'applied science' guy had an electron microscope capture of new and old toothbrushes and it was the differences between needle sharp edges and worn out clubs.

I got one of those little spritzers, like for putting perfume or febreeze in, filled it with 3% h2o2, and spritz my electric brush every day after I rinse it, cause it was getting a little grody in the crevices. Works great, dirt cheap.

Do you refresh the H2O2 every day?

I don't do it personally, I would if I was paranoid about germs.

My wife uses those denture cleaner pills. They work amazingly well.

The point of brushing your teeth isn't sterilizing them. The point of brushing your teeth is to reduce the number of nutrients for bacteria to feed on, and to physically disrupt their environment - like running a lawnmower over an anthill.

Isn't there something about changing the ph balance?

For me the "unbreakable" floss string combined with a floss pick in this particular product: https://www.amazon.com/DenTek-Triple-Clean-Floss-Picks/dp/B0... was a massive innovation that finally allowed me to regularly floss easily at the age of ~30.

Prior to that I couldn't handle the floss string well, and all other floss picks (even nearly identical ones from the exact same brand) just snap apart between my very closely-spaced teeth.

Totally agree there's too little innovation in this field.

I hadn't heard of the Buzz Brush and it's fascinating to me, although it does look half-baked and too indie at the moment for me to trust it with my dental health.

Also it's too expensive to try as a throwaway test.

Any other cool innovative products that replace standard brushing?

Not that replace standard brushing, but I worked with a company in Denmark called Novozymes. They produce enzymes for a variety of applications including dental care. They have a set of enzymes that they license to Unilever for a toothpaste called Zendium, which has some market share in Northern Europe. The enzymes break down microfilm that develops on teeth, making brushing more effective. There was RCT done on it I believe, I read the paper years ago, can't seem to find it now though.

Any concern those enzymes would get swallowed and break down membranes in the digestive tract?

Seeing as they pass through the acid in your stomach (and will denature there, which is the point of your stomach) you must be primarily worried about any of the bits before that. These enzymes are made to go in your mouth. If they dissolved the tissues in there they wouldn't be appropriate for that, so this is not a concern.

Based on the video, I wouldn't implicitly trust the brush to have enough precision to hit the small chunks of food at the gumline.

Not buying it. That would only work if it were firmer because as it is now I'm extremely doubtful your teeth will magically fall into those grooves when the sponge has so little structure. On top of that it seems hard to clean, A toothbrush is open and has short bristles and often after rinsing it I'll look and still find debris where I need to clean again and deliberately get pieces out.

In grad school, one of my friends worked for a US medical device manufacturer. They had several dental innovations that they did not bother to market in the US because the regulation to get approval out weighed what they felt the market offered. They made their profits in other countries and were happy with that.

Have you seen how much it costs to get crowns or implants? There’s zero incentive for innovation, people keep bringing their money.

You could say this about almost every job. I like to think that the entire population isn't trying to actively sabotage things to generate more work. I certainly don't go seeding bugs or complex situations in to software to create more demand for my job.

It’s not about sabotage. Just that there’s no incentive to invent a new generation of dental hygiene products.

I would like to think that most dentists like their patients to have healthy, cared for teeth and that they play in important role in it. I would not like to think that most of them actually work to our detriment so that they can do more expensive, painful procedures on our mouths and teeth. That’s a pretty cynical outlook I’d need to see evidence for.

I’d like to think that, but my dentist makes about $170/year from me having healthy teeth. They make $1500/crown (in addition to the $170 for cleaning).

I’ve been to three dentists this year. I find it interesting that one said I had an emergency and needed a crown right away (a year ago), one said they’d watch the tooth, and one said nothing.

Cynically, I don’t like agency issues where experts make lots of money off their advice and it’s difficult to double check.

I had a dentist for several years and everything was normal just clean and go. A new hygenist shows up and suddently "You have severe plaque below the gum line we need to do a deep cleaning (root scaling/planing)" so they do that and it's almost $500, next time rolls around and she says it again and dentist concurs. I had been brushing and flossing diligently (probably too much) since the last time and just looking at my teeth saw nearly no plaque. I left and said I'd call them back to schedule. I go to a new dentist the following week and they say I have lovely teeth and it looks like I've been taking great care of them, then I tell the dentist what the previous one had said and he's like "listen, I'm not going to bad mouth anyone, but your teeth look great, they just need a typical cleaning that you came in for". That's when I knew something was really wrong with the other place, so it happens. I know my story is anecdotal. Personally I think my old dentist got rid of her previous hygenist that wouldn't agree to hornswoggle patients and they tried to get me to do expensive treatments.

Both myself and my partner had similar experiences at the dentist. They found work that needed to be done, we got second opinions, and were told something completely different.

I stopped trusting dentists since then. If I can feel or see a problem (in the mirror or in xrays), then sure, I'll get it fixed. But, if my teeth feel perfectly fine, I'm not going to rush into getting them drilled out.

I had four different opinions in the last two years:

- It gets inflamed because other teeth keep pushing on the gums. You need to get them pulled

- I don’t know why, let’s just apply antibiotics for the 10th time

- It’s a cavity, let’s wait till it grows

- Use these tiny between-teeth brushes for your gums

The last one actually helped.

All you need to do is visit the dentistry reddit sub and look at threads like this: https://www.reddit.com/r/Dentistry/comments/vnv25a/how_is_he.... They all operate on "production" because billing is top priority.

I don’t doubt that money is their highest priority, as that is the case for most people when it comes to their job. But the implication that they are sabotaging our teeth or giving bad advice in order to be able to bill us for bigger procedures down the line is a much bigger claim.

It happens. From https://www.theatlantic.com/magazine/archive/2019/05/the-tro... :

> Year after year, Lund had performed certain procedures at extraordinarily high rates. Whereas a typical dentist might perform root canals on previously crowned teeth in only 3 to 7 percent of cases, Lund was performing them in 90 percent of cases. As Zeidler later alleged in court documents, Lund had performed invasive, costly, and seemingly unnecessary procedures on dozens and dozens of patients, some of whom he had been seeing for decades. Terry Mitchell and Joyce Cordi were far from alone. In fact, they had not even endured the worst of it.

Of course it happens. I didn’t say, “it never happens.” I’m saying most dentists don’t behave that way.

They don't have to sabotage people, all they have to do is nothing - in terms of researching new better ways to prevent issues - and they're already set.

No incentive to innovate is very different from sabotaging. I’m sorry you see it this way.

Generally, I would agree that most dentists want their patients to have healthy teeth. In my dentists they seem relatively thorough and consistent in what they observe with my teeth as far as health and function. And they are pretty specific with preventative measures that don't make them money (recommendations on possible problem areas to make sure to focus on for flossing brushing) and some that do (mouth guard to prevent grinding).

HOWEVER, all of the dentists that I have had push cosmetic procedures really hard. Teeth whitening, alignment (cosmetic only), caps (cosmetic only).

A close friend of mine is a dental hygienist. He once worked for a dentist in Ketchum, ID who had all the hygienists on a commission structure. Basically he was told to “sell” procedures that were virtually not necessary. Some of his coworkers were making $250k/yr as hygenists… Needless to say, he couldn’t stomach it and left the practice. He’s worked for many dentists and he ultimately left the field because the majority of clinics he worked for tended to be a business first and look after your best interests second.

You’d be surprised but dentists care about making money to provide for the family. Just as most of us who work. They don’t sabotage anything, there’s no master plan. They just come in, see your cavity, make a 300$ filling or 1000$ crown. Rinse and repeat. Then they clock out and go home.

So who’s actually going to actively work on creating new groundbreaking dental products? What would the incentive be?

My daily tooth care consists of 3 steps:

1. Clean between teeth by using an interdental brush

2. Clean between teeth by using a water flosser

3. Clean teeth surface by using an electric brush.

I am not sure how would the sponge replace these 3 steps.

I remember some articles about good bacteria outcompeting bad bacteria in the mouth and preventing cavities. Seems like it probably didn't pan out.

Nah it did, the problem is you have to take a pill every day and they cost way too much for that sort of frequent usage. Like $60 per 20 pills kind of price, which is hard to justify without hard proven evidence of actual benefit.

How did you get this price? Can I get them somewhere? $3 per day to never have teeth issues again is an absolute bargain.

I think I saw it on amazon a few years back? It's possible there wasn't enough demand to keep selling it, but I've also no idea what it was called anymore.

I want something that I can use in the office (i.e., without easy access to a sink).

idk, I think the 1 pack means that people are wiling to try it but have not decided as a mass if they want to continue use. It doesnt mean its a bad product

It’s just an over regulated industry where it’s too expensive to try new things.

Dentistry exists all over the world...

Capitalism only creates innovations where there is potential for expanding profits. Permanently fixing teeth is infinitely less profitable than keeping them in a constant state of disrepair.

This looks like a really bad dropshipping site...

Especially considering the fact they've imported reviews from elsewhere, like AliExpress (even has the same name format, C**e).

If you're young, don't laugh.

Once I turned 40 my dental hygienists really spent a lot of time educating me on how to properly brush my teeth. It really requires delicate care. (Remember, most of our ancestors didn't live to be old enough to need delicate dental hygiene.)

If something like this works, it'll be wonderful. Carefully cleaning my teeth when I'm half asleep is not fun.

>Remember, most of our ancestors didn't live to be old enough to need delicate dental hygiene.)

Really low historical life expectancy figures are mostly due to extremely high infant and childhood mortality as well as higher mortality in childbirth. It's not like adults were elderly at 40.

Yep, if you lived til 16 you could easily and not surprisingly live to 60, after that it goes down hill pretty fast for most people without modern medicine...They didn't have a lot of retirement plans back then unless you were lucky enough to have some kids that wanted to keep grandpa around.

If it makes you feel better most people don't brush their teeth correctly (supposed to hold toothbrush at a 45 degree angle along the tooth/gum line). I think there's another future where brushing and flossing largely become obsolete. If we could develop a more effective mouthwash tailored to restoring each persons oral microbiome we could likely reduce the need for brushing and flossing (and instead replace it with a daily rinse). A lot easier than half asleep brushing!

I turned 40 a few years ago and finally moved over to an electric toothbrush and my dentist has noticed improvements.

Ultimately an electric is similar to a human but I like that it's consistent. Consistent pressure on my teeth and consistent time in each quadrant as well.

> most of our ancestors didn't live to be old enough to need delicate dental hygiene

They also didn't consume so much tooth-destroying garbage as we do.

I think we consume 10-20 times as much sugar as people even 100 years ago. It's pretty crazy, although white bread isn't great for your teeth either since it's only one step away from sugar.

Then again, medieval bread that was cut with sand wasn't any better for teeth either.

As a health care worker this would be great for very fragile or palliative clients where brushing effectively just isn’t possible. Fragile clients will often do a poor job or if you help them they don’t always tolerate how hard and long you need to brush to be effective. Not to even mention flossing. And with palliative patients they can often be bed bound and unconscious to you can’t really get in with a toothbrush and water and brush properly. Instead they get a small piece of foam attached to a stick basically and you rub it around their mouth and get any big chunks out. Very poor effectiveness. For me good mouth care for the palliative clients would be really nice to see.

I don't recall where this story is from, but I've read it somewhere.

It's a story about a guy who invents shaving microbots, which you apply in your face, who do all the work. Iirc they were on a gel, though ultimately that doesn't matter. At some point they supposedly deactivate themselves for some reason I've forgotten, to prevent them from doing harm in case they enter the body.

The end of the story is that the inventor, who kept using his microbots, eventually died of unknown cause. The autopsy showed that he had pneumoconiosis/silicosis, aka a dry, dusty lung.

Because he kept inhaling them. Microdroplets of liquid, containing microbots.

I believe this story isn't far fetched. Imagine you have thousands of these teeth brushing bots in your mouth. If you have some on the back of your throat, you will eventually have them in your lungs. All it takes to accumulate enough of them to cause issues is repeated use and time.

I guess this is the first step to nanosites[1] from "Diamond Age" by Neal Stephenson.

[1] https://en.gyaanipedia.com/wiki/Nanosite

I’ve been waiting, since reading that book, for nanobots that brush my teeth, trim my hair, shave, etc so I wake up every morning and not need to do this stuff.

This is really neat. But I remain skeptical

> In both instances, a catalytic reaction drives the nanoparticles to produce antimicrobials that kill harmful oral bacteria on site.

So, what happens if I swallow this stuff that I'm putting in my mouth?

Nothing that isn't already happening. There is magnetite in many foods already. Often as inexpensive iron fortification.

Also, your cells are more robust to external reactive oxygen than bacteria.

The catalysis occurs when hydrogen peroxide is "activated" by the magnetite to produce singlet oxygen, which then goes on to damage biofilms and bacterial walls. Your epithelial cells are basically expendable.

Internal ROS isn't good, but that isn't the case here.

Nanomachines, son! They brush my teeth in response to mastication.

Don't masticate with your mouth open

So as an aside; Ciliac Disease is caused by the body falsely thinking [this was that] and attacking its own internals...

SO...

Lets assume that you add these and then they get ingested (which ALWAYS happens in brushing teeth) --> long term "micro-biome-biotics" affect on gut biome)

Gut biomes are the most important health aspect for nutrition we should be plugging AI into...

This seems like it will result in not-good outcomes.... Imagine programming "toothpaste" such that the bots that ARE ingested devour/destroy/attack/plant-payloads on cells in the system...

---

Future Bio-Cyber-Nutrition attacks:

A powder that is applied to a food substance that survives heat, cooking ; results in the bio-breakdown or attack of the individual.

Level III: A recon biometrix that can be ingested and give the gut bio of a target.... in order to create a specific attack vector.

Levvel IV: an agent who can determine dietary habits

Level VI: Spore attributed to specific diets.

---

Cyber warfare is not just computers ; its protein folding...

When we were "folding proteins" for health.... Health can be - OR + <-- When we use the term "for health" ... it is ofr hte '-' <-- We are designing proteins to kill. Not heal. UNLESS you're Thiel.

I wonder if in the future this could be used to help care for people in long term hospital stays who are unable to brush/floss, or people who require at home care. Very interesting idea but I think it will take a long time for the general public to adopt this tech.

Can anyone recommend an electric toothbrush? I have always used a regular manual one, but lots of people including a dentist have recommended an electric one. Wanna see what the hype is about.

I've used regular $10-$25 electric tooth brush for a decade and assumed they're good enough.

I've gotten Phillips Sonicare for holiday, and understanding that this is anecdotal evidence, I am shocked at its increased ability to dislodge food from the crevices. I could swear that sometimes the vibration it puts on the tooth, dislodges food from places it's not yet directly touching, just through the vibration through the tooth, which never happened with cheaper electric brushes. Overall, my teeth feel far cleaner afterwards, kinda like after the dental hygienist is done. So it gets my support, expensive as it may be.

> Phillips Sonicare

Which of them? There are many models, right?

I got a higher-end one as a present like a decade ago, I believe it was the Philips HX 6932/34 FlexCare.

Has a whole bunch of programs, most of which I didn't use, some I've come to like and wouldn't want to miss anymore; Extra white is for when you want to get them really polished, and gum care when you want to go to town with some gum message.

Getting the brush heads can be a bit of a running cost, original ones can be pricey, cheaper alternative "off-brand" brushes exist. But I'm not sure I want my gums brushed by something that alleges to be of some kind of material out of China.

Love the little UV box they can be bundled with; Usually will UV clean the brush head while showering, and when I get out to of the shower I have a freshly disinfected brush to toothbrush with.

Last year it started acting up, randomly turning on when not in use, until it didn't really work anymore.

Got myself the Philips Sonicare HX6850/57 ProtectiveClean 5100 as replacement. Not as high-end as the last one, sadly it also feels like it in build quality, but has all the programs I want and has been working fine so far.

It appears to me that they they are all "basically good enough" and very different to the $10-$25 electric brushes. My wife has fancy, I have basic model, and honestly we can't really tell the difference.

I don't really find value in timers, beeps, bluetooth, etc.

Most of them operate the same way when you consider just the vibrating on the tooth part. They differentiate the models with extra features like timers and Bluetooth or NFC brush heads and whatnot

The cheapest model is already most of the way there, though the higher end models do clean at twice the frequency so those might be somewhat better.

Philips Sonicare is the way to go. Lot of different options, but they're all great.

Philips sonicare + Waterpik flosser. Sensodyne Repair&Protect (has NOVAMIN that restores the teeth)

Maybe NOVAMIN doesn't do much: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7068624/

It's been awhile, but back when I tried one I didn't care for the Sonicare. Simply it made my hand numb.

Haha yeah it takes a week or two to get fully used to it, I know a few people who just couldn't stomach it.

Oral-B Pro 1000, don't even look at the more "premium" versions, all it has is extra bells-and-whistles like bluetooth that really don't anything to its basic function.

The oral-b ones are very good. Sonicare's have big reliability issues in my experience.

The cheap Oral B one is fine in my book. I've gone through a couple (battery slows down over the years). Honestly the no1 feature of an electric toothbrush is the timer (30s x4).

I'm looking forward to the day when we have bio-engineered slugs that feed off the left over food in our mouths while we sleep. If their trails can strengthen enamel all the better!

Thanks, but I rather not choke on slugs in my sleep.

Don't get too excited. It's

>> ... a proof-of-concept study...

This was envisioned in a science fiction story or novel decades ago, but I can’t remember where I saw it! It might have been a novel by Robert Heilein. It was just mentioned in passing in the story, but since that time I’ve wondered if it will ever be realized; I thought it might take the form of a small robot about the size of a June bug that would slowly crawl around in one’s mouth while we were asleep.

Wait so, what do these microrobots actually look like? Are they just small black bristles that you put in your mouth?

Iron nanoparticles controlled by a magnetic field it seems like.

The thing I'm curious about though is, how do they remove all the iron particles afterward? Would I just get a month's dose of iron each time this thing brushes my teeth?

Suck on a big bar magnet!

Really, that would do. Better still would be an electro magnetic retainer. Then the particles cloud be captured and returned to a container.

I doubt iron nano particles would be reusable, but you wouldn't want them down the sink as they would likely be nucleation points for rust

Is anyone familiar with the health consequences of inhaling or otherwise ingesting nano iron?

More magnets?

Yeah, the name is really misleading, if I’m understanding the tech correctly.

Wait, news on actual irl Drexlerian nano?

> may one day..

oh, nevermind. Microbots "may one day" do shit, not "can".

I swear it amazes me sometimes how advanced dental care technology continues to push in the US.

Wasn't there a Professor in Florida I think that introduced a new plasmid to the bacteria normally in our mouth and proved to prevent tooth decay? I've tried to look for it, but haven't been able to find it again.

Key feature is swallowing the dentic as harmless. Risk management is the priority.

This is probably one of the worst visual representation I've ever seen.

ffs, that's about time. I can brush my teeth just fine, I just hate doing it and I felt like this field had been lacking advances like this for a very very long time.

"What ever you do, _never_ swallow the Dentic"

... "dentifrice"?

It's a quote from Farscape... unlike other shows, they were _very_ intouch bathroom habits in space. ;)

No thanks on putting nano-particles in my mouth.

Take my money…

Pro Tip: Buy a professional dental pick. I bought one on Amazon for around $35 about 10 years ago. I use it every day. It works great.

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