School dental program prevents 80% of cavities with non-invasive treatment | Hacker News Reader

School dental program prevents 80% of cavities with non-invasive treatment

nyu.edu

205 pointsvoisin136 comments

My (dental hygienist) mother insisted that I get a sealant on my teeth when my permanent teeth came in, and to this day I’ve never had a cavity. Definitely doing the same for my kids.

I always wondered why the topic of sealants was always related to children and figured it was somehow only appropriate for teeth with an approaching end date. Are there any issues such as needing to reapply it every X years?

Never heard of dental sealants before this. But from a cursory search, you can only use it on clean teeth, so no fillings or cavities.

As you get older your teeth have worn smoother so the pits being filled are less serious. I did have a failed sealant result in a compositing of the surface of one of my teeth.

Some sealants contain BPA derivatives though. I'd rather have cavities than xenoestrogens messing up my hormonal system, so any non resin sealant is a great step forward

So what sealants are good/best ?

I am not qualified to say what is best, but glass ionomer cements (the ones without resin) do not contain plasticisers.

Surely exposure from composite resin falls off quickly over time and pales in comparison to our constant environmental exposure to plasticizers. Any data on this?

“Surely” seems a bit over-confident unless you’ve seen some research, but it does seem likely.

Surely it is worth it minimising every single source identified

No it's really not. It like saying you want to maximize the amount of money you have. You don't suddenly stop eating. Because the utility of eating supersedes the cost (in this case literal money) of buying food.

If the BPA derivative exposure in this sealant is low enough compared to usual daily exposure the benefit of having an effective sealant is too great to overlook. Let's say (for example)usual daily exposure is 1, the sealant adds 0.0000000000000001. Considering how devastating teeth problems can be this cost is a no brainer to pay.

Same here. My father was a dentist and insisted on sealant and maintained them until around 20. No cavities and almost 40.

During my bi-annual dentist visits they always mention the sealants on my teeth (maintained with the last touchup done when I was 16) and I'm sort of surprised they're largely intact. I'm 41 and haven't had a cavity since I was 13, on an adult tooth that I just missed my chance to get sealed before the cavity happened.

Eh, I had sealant when my adult teeth came in. I still had a few cavities. My teeth naturally have very deep pits and fissures. Apparently that has some bearing on the likelihood of cavities. I wonder if that also effects the success of sealant application.

I stopped getting cavities when I stopped rinsing all of the fluoride away after brushing my teeth. If you wish to rinse, do so after a few minutes. I told this to my dentist and he said he wished that was more common knowledge, yet he's never mentioned it to me. Go figure.

I stopped getting cavities when I started using fluoride-free toothpaste and filtered my water with reverse osmosis. But correlation is not causation and all, so it was probably due more to not eating sweets so much anymore, brushing and flossing properly and without fail twice a day, and maintaining a healthy immune system through sleep, exercise, and a good diet.

Fluoride is effective at remineralizing your enamel. Fluoride isn’t just for cavities.

What other uses does mineralized enamel have, aside from resisting attack by plaques? Honest question.

Plaque and tartar eat away at your enamel causing caries. Remineralizing is important to restore what has been taken away. So it’s not so much about resisting attack (I don’t believe fluoride fights bacteria) as much as reversing the attack.

You are much better off using nanohydroxyapatite for that, though; you can easily import such toothpastes from Japan via Amazon.

Source?

Not really a source, but this Dental Hygienist talks a bit about hydroxyapatite. Sounds like it could be of at least equal effectiveness. Though further studies are needed. https://youtu.be/kQAPEZaqwfY?t=63

Not OP but I have a family member who’s a specialized dentist who’s well regarded in the field and constantly harps on this kind of toothpaste over fluoride. I think fluoride is basically cheap and that’s all

Interesting. Hadn’t heard it it before, but at least according to this and it’s linked paper it’s roughly equivalent. What makes you say that you’re better off?

https://www.rdhmag.com/patient-care/article/14276225/nanohyd...

See also the bioactive glass compounds BioMin (fluoro calcium phosphosilicate) and NovaMin (calcium sodium phosphosilicate), which come in toothpastes that also include fluoride to cover all the bases.

https://ceramics.org/ceramic-tech-today/biomaterials/bioacti...

BioMin F is as effective as nanohydroxyapatite, and is less expensive than the Apagard nanohydroxyapatite toothpaste. (BioMin F is not yet available in the U.S. and needs to be imported.)

https://www.journalcra.com/sites/default/files/issue-pdf/317...

I use this stuff and I stopped getting cavities. Just one example obviously, but it was night and day better I think. It's a little pricey is all.

It's great for tooth sensitivity as well.

there is boka an American company. there are others as well, no reason to import from japan.

Perhaps, but how much of a difference does it really make? Your saliva remineralizes your enamel naturally. I've gone over 10 years without fluoride in my toothpaste or water and my teeth are in perfect condition, at least according to the dentist. So is the toxicity of fluoride worth some clearly minor and perhaps not even necessary improvement? I used large quantities of fluoride as a child, both in toothpaste and mouth washes, and still got 10 cavities.

Everyones teeth, diet etc are different. What works for you may not work for others.

Most people benefit significantly. That has been proven in study after study. The toxicity has not been, or it wouldn’t be widespread world wide. I’m glad your genetic makeup, diet, microbiome, etc is working out for you. That may or may not change with time.

The CDC says there’s a 25% reduction in cavities for children due to fluoride [1]. So it’s not like fluoride is only for cavity prevention, and perhaps your teeth would have been even worse without it.

[1] https://www.cdc.gov/fluoridation/index.html

I've gone through several studies and you are not representing the field fairly. There are many studies going both ways. It's far from a slam dunk consensus. Furthermore, there is absolutely no question that fluoride is toxic. It's just a question whether the amounts in water and toothpaste are enough to cause measurable negative effects.

Considering this, why don't we add things like B12, magnesium, and vitamin D to the water? They are all deficient in a large percentage of the population and cause severe problems, far worse than dental caries. The reason they are not is because it's not the business of the water supply to act as medicine for the general populace. It should come from individual products. You see fortified foods and vitamins, as well as fluoride toothpaste and mouth washes.

Could you cite your sources? I’m genuinely curious. There’s a lot of quackery out there on this since the tin foils love to accuse fluoride of somehow being a gov brain control method.

Of course fluoride is toxic at a certain level - so is water! The dose makes the poison. The question is if it’s a worthwhile trade off for society, and is it toxic at the levels used. It can’t be too toxic given the extremely large populations that have received it for decades without people dropping dead because of it. In fact life expectancy has only gone up since it’s introduction in 1945. Municipal water I believe is chlorinated as well, which in sufficient quantities is bad, but in small amounts is worth the trade off to kill the germs.

The US requires flour to be enriched with thiamin, riboflavin, niacin, folic acid, and iron. So there are other mandated ways to achieve vitamins in public health. My guess is water just isn’t an appropriate vector for those things for a variety of reasons, but that’s pure speculation. It’s an interesting question. On the other hand, I don’t believe you’ll naturally get fluoride anywhere else but injected into your water (or naturally occurring), so that’s probably a good deal why.

This is not a good faith argument to claim that fluoride and water are in the same class of substances when it comes to toxicity.

Also you are wrong that all flour in the US must be enriched. I have some unenriched flour on my shelf right now.

https://www.hsph.harvard.edu/news/features/fluoride-children...

The Harvard quoted study above looks at children in China in areas with high levels in groundwater .. high being of the order of 3-11 mg/litre.

The correlated 'damage' cited was of less than half an IQ point observed difference at the upper end of the high levels.

The fluoride doses used in water treatment (here in Australia) are at most 1 mg/litre.

The amounts with measurable cognitive deficits were less that the amounts added to drinking water in the US in several of the Chinese regions. It's in the study's data.

The study Developmental Fluoride Neurotoxicity: A Systematic Review and Meta-Analysis [1] (discussed in your link above) has data on drinking water in China.

It includes quotes relavant to the USofA:

    Such circumstances are difficult to find in many industrialized countries, because fluoride concentrations in community water are usually no higher than 1 mg/L, even when fluoride is added to water supplies as a public health measure to reduce tooth decay.

and

    In response to the recommendation of the NRC (2006), the U.S. Department of Health and Human Services (DHHS) and the U.S. EPA recently announced that DHHS is proposing to change the recommended level of fluoride in drinking water to 0.7 mg/L from the currently recommended range of 0.7–1.2 mg/L, and the U.S. EPA is reviewing the maximum amount of fluoride allowed in drinking water, which currently is set at 4.0 mg/L

Note that the U.S. EPA is reviewing the maximum amount of fluoride allowed in drinking water concerns levels naturally occuring and is not a recommendation to add fluoride to US drinking water in excess of 1 mg/litre.

I am unable to find data in that report that supports your assertion.

If you have data you wish to draw eyes to then please quote the numbers and link to the source.

[1] https://ehp.niehs.nih.gov/doi/10.1289/ehp.1104912

The problem is that it's an EPA recommended dosage, and not regulated nationwide, leading to a large variance in levels. "The fact that fluoridation of water is not regulated nationwide leads to a challenge for individuals interested in generating meaningful data for nationwide databases." [1] In the short list of measurements in the quoted paper, it ranged from almost nothing to 1.5 mg/L, and that's a very small sample. Borden County in Texas has levels above 5.5 mg/L in some areas [2]

[1] https://www.ars.usda.gov/ARSUserFiles/80400525/Articles/jfca...

[2] https://www.beg.utexas.edu/files/content/beg/research/TCEQ_s...

You still have not supported the claim made above that:

> The amounts with measurable cognitive deficits were less that the amounts added to drinking water in the US ...

Your first link ( [1] ) cites a source in Springfield as the maximal value seen (in that report) of 1.5 mg / litre (with no mention of whether that's due to added fluoride or a result of natural fluoride in the groundwater).

Your second link ( [2] ) is about an untreated groundwater source that serves 150 people with:

    Fluoride has been detected between 4 milligrams per liter (mg/L) and 5.57 mg/L from July 2002 to March 2007, which exceeds the maximum contaminant level (MCL) of 4 mg/L as well as the Secondary MCL of 2 mg/L set by the USEPA.

and is titled as a DRAFT FEASIBILITY REPORT looking at the costs of treatment with (for example) :

    Centralized treatment alternatives for arsenic and fluoride removal have been developed and were considered for this report; ...

To summarise; you have claimed but not demonstrated that intentional treatment in the USofA has added fluoride to reach levels that (are assumed | correlated ) caused IQ losses of less than half a point in China.

Your link clearly do not support this, Borden County is untreated and the intent is to look at reducing the high fluoride levels.

You should re-read the study I linked:

"The average loss in IQ was reported as a standardized weighted mean difference of 0.45, which would be approximately equivalent to seven IQ points for commonly used IQ scores with a standard deviation of 15."

Seven points IQ difference.

Also, if you bother to look at the data in the linked paper, many of the regions with measurable deficits were in the 0.5 to 2 mg/L range, well within typical treatment levels in the US.

Fair point re: IQ - I misread that.

> Also, if you bother to look at the data in the linked paper, ...

Excuse me? Mind the shade please.

> many of the regions with measurable deficits were in the 0.5 to 2 mg/L range

Exactly how many of the 27 studies listed actually had "high" fluoride values in that range?

If you bother to look at the data you might concede it's not "many" by a long shot.

More to the point, in those few studies with low fluoride levels how much was IQ correlated to fall?

The meta study findings were:

    Findings from our meta-analyses of 27 studies published over 22 years suggest an inverse association between high fluoride exposure and children’s intelligence. Children who lived in areas with high fluoride exposure had lower IQ scores than those who lived in low-exposure or control areas.

Note Well: "than those who lived in low-exposure or control areas."

It's a meta study.

It looked at studies with low levels of fluoride AND at studies with high levels of fluoride.

It determined that high levels of fluorine are not good (and that many of the studies had other issues such as lead, arsenic, iodine that had to be dealt with).

I’m not implying they’re in the same class, I’m saying that the level used is implicitly important in saying whether or not something is toxic. To me it’s not a good faith argument to assume otherwise.

You’re right I was wrong about enrichment [1] - I didn’t know that. It is wide spread, however.

The study you cited seemed to be from areas of naturally occurring high levels. So I guess I should further qualify my statement - I am to mean that it’s non-toxic at the levels used in municipal water and in toothpaste. I thought you were saying there were studies suggesting otherwise at the levels used, which the CDC disagrees with [2]. I’m now rereading your comment where you talk about the levels used so you did address that. Apologies for not better latching onto that. But it did make it sound like these levels in use were potentially toxic, which has been very widely studied across many countries over decades with increasing life expectancy and dental improvements, so it would be very unexpected if so.

It seems that there isn’t a federal requirement for fluoride in municipal water - perhaps there are areas that don’t.

[1] https://www.fda.gov/media/94563/download

[2] https://www.cdc.gov/fluoridation/faqs/community-water-fluori...

To claim that dose is the only factor involved is bad faith, or at least overly simplistic. For example, radiation and lead are cumulative. There is no minimum safe dose. Can you say definitively that there is no damage or cumulative effect from regular small dosages of fluoride?

Did you look at the study? The naturally occurring levels are below levels added to water in the US in many of the regions studied.

In any case you should be able to see that I'm not coming at this from some conspiracy nutjob angle but from sourced studies and reasonable thought processes.

My point is not that you are wrong. It's that, even if you are right, it's not some obvious open and shut case.

The various soaps that toothpaste is made of are not so great to leave on your mouth. If it can cause canker sores and various skin conditions in some people.

Instead just get a fluoride rinse, they're not expensive and considerably better for you than soap.

All of these posts have me wondering how commonplace cavities actually are. I stopped getting cavities in my preteen years, about 35 years ago. The only change I made was actually brushing my teeth regularly, which very young me always tried to avoid despite my parents' best efforts.

I'm sure my consumption of things like refined sugars has gone steadily down in that time, but not as part of a conscious effort. Being a kid in the 80s meant you ate a ton of crap :)

They're still pretty common, at least in the people I hang out in. You're very lucky you've not had any cavities since preteen. I've done allot to change my diet to strip out all sugars, refined carbs, acidic foods / drinks etc. But still get cavities.

It's a journey, sometimes a long one, to get to a spot with good oral heath. In my case, I had poor heath education. I didn't know what I didn't know. Like visiting the dentist is not equal to visiting a dental hygienist. Up until a few weeks ago, I had no clue what a dental hygienist was or if I should visit one. My dentist never recommended one, so I thought it wasn't needed. But I recently booked an apt with a dental hygienist at another practice, it was 100% needed.

From my understanding, a dental hygienist is more preventative work (and cleaning), while dentist is more the surgeon who does the fixing after an issue has occurred.

I learnt a tonne in my first ever dental hygienist visit. Basic things I wasn't doing for my oral heath. Like flossing... I never done it for years cos I thought it wasn't that big of a deal and cos I thought my teeth were to crammed together, but I learnt (and she showed me) that you can 100% floss my teeth and you defo should!

I wish some basic oral heath was taught in school, and that dental (at least 6 months/yearly checkups were free/govt funded), it's so important, and so expensive these days, even for a checkup.

It's especially tricky when you want to learn so much while at the dentist/hygienist, but know it's costing you $$$ so don't maybe ask everything. Personally the Teeth Talk Girl YouTube channel has helped me so much and gave me the courage to go back to the dentist (after not going for ~5 years).

I highly recommend the channel if you want to learn more on what good oral heath is. https://www.youtube.com/@TeethTalk

I was prescribed a high fluoride mouthwash, after a tooth implant, told not to rinse.It seems there are high fluoride toothpaste that is a bit expensive.

I never got sealants but did get fluoride treatment and brushing twice a day as a kid. I never had a cavity either and even as an adult I can maybe count the number of cavities I had on one hand. (And I brushed my teeth maybe once a day, don't judge me.) Honestly my diet played a huge role here, but the sealants, fluoride, and twice daily brushing just give you so much more protection than you could expect from brushing alone.

I don't floss, brush once per day and have never heard of sealant, and I also have zero cavities. n = 1

It boils down to your dentist, too. Some will leap to drilling and filling every little speck they can find (and charge you for it), while others will monitor them and see if they progress.

Having been to both types, I’d say I strongly prefer the latter.

The former makes me irrationally angry. Once you have fillings, it's apparently rather easy for more cavities to form right alongside them. As a teen, I had a dentist who drilled out every speck in a majority of my adult teeth. Since then, every cavity I've had for the rest of my adult life has been a cavity that formed adjacent to one of those fillings.

That's weird, I was terrible at brushing my teeth as a teenager and have 4 or 5 mercury fillings from then, once I started being a bet more hygeine conscious in college I've not had a cavity since and that was 20 years ago.

I had the latter kind growing up. Moved away, and went to a dentist with a fancy name and close to my office. Huge mistake. I’ve lost track of how many they drilled. My mouth hasn’t been the same since.

I have a new dentist now who’s much like my previous one. My advice to anyone with a new dentist - if your new dentist suggests a bunch of new fillings when your track record differs dramatically, get a second opinion!

Yup, sadly many of them (in greater Los Angeles area) tend to over "find" cavities so they can put money in their pocket. This is not ethical, but I've had different dentists do this and I simply left for another dentist.

Some people have harder teeth genetically. Probably also diet matters. And habits that alter salivation.

Yeah this, everyones teeth are different. And we all have different enamel thickness etc. And diet definitely plays a role.

Also, it's not inherently bad to brush once a day, IF you're doing a crazy effective job. It's recommended to brush twice a day because most people don't do a good job, so best to disturb the plaque twice a day before it hardens into tartar (which only the dentist can clear). Plaque usually hardens within 48 hours.

But always best to talk to your dentist / dental hygienist about what's best for you teeth, as everyones teeth (diet etc) is different.

Yep. I've had maybe 2 cavities in all of my life, from teeth where sealant dislodged. Didn't need teeth alignment until well into middle age.

I stopped getting cavities once I started brushing twice (or at least before bed) and flossing. Yeah that’s all it took.

Same. I'm 38 and have never had a cavity or filling.

Sounds interesting, if you don't have caries in visible parts of your teeth!

I did a quick search and it's apparently also an effective treatment for adults:

"According to an umbrella review, application of 38% SDF prevented root caries in adults with success rates 72% higher than a placebo treatment. The same review reported a prevented fraction for successful root caries arrest, between 100% and 725% higher as compared to a placebo treatment.21 Moreover, application of 38% SDF in combination with oral health education was found to be the most effective method for preventing root caries in adults."[0]

[0] https://www.ada.org/resources/research/science-and-research-...

Interesting. Thank you!

Btw why aren't dental sealants a good treatment for adults ?

I asked my dentist last year. She told me that old teeths have microfisures and to seal she would have to first remove too much of the teeths to clean out these fisures before sealing.

Maybe your dentist can tell you more.

My teeth naturally have deep pits and fissures. I had sealant and still got some cavities. I wonder if that affected its success.

Depends a bit on the person but I had new sealants placed when I was 25.

My brother is a dentist and he says the main drawback of SDF is that it looks bad. It indeed stops the decay but turns the tooth (or part of the tooth) black.

It doesn't stain healthy enamel, but it does permanently stain parts with cavitation: https://www.sproutpediatricdentistry.com/blog/pediatric-dent....

!! I wouldn’t mind

Yes it works, but the part they don’t mention is that the treatment is black as black gets. You have to be very careful about where it goes, or it can affect the self-confidence or the kids, and possibly exacerbate bullying.

There's a case report [0] where they were able to reverse the staining with a potassium idiode treatment, might be a potential solution in the future.

[0] https://meridian.allenpress.com/operative-dentistry/article-...

Poor Dental health has been linked to heart attacks. Also root canal is like pathway for bacteria to enter blood stream and cause life long source of inflammation. Potential benefits to humanity woud be so big. Even if it stained teeth would be worth it.

> The study included 2,998 children in kindergarten through third grade at 47 New York City schools. The schools—which serve a racially diverse group of students, most of whom are from low-income families—were randomized to receive either the simple or complex treatment.

Was this selection because some low-income families need this kind of treatment more than affluent ones? Or represent a diversity of racial backgrounds against which the treatment can be better tested?

Was it a factor that they were cheap subjects? Or maybe unlikely to know any lawyers?

As a kid, our (modest, Catholic) grade school participated in a lengthy toothpaste study. The incentive, AFAIK, was you got free toothpaste for your family (and I seem to recall some free toothbrushes).

As an adult now, aware of some history and societal dynamics, if I ever have kids, and they came home with an experiment subject consent form, one of the questions on my mind would be "Are the children of the wealthy and connected also in this subject cohort?"

I am sure there is some study somewhere that samples rich people rather than others.

I don't know anything about this study, but am a lifelong NYC resident whose kids have gone through the public school system and who also has been directly involved as a "parent leader" in some DOE programs. With some confidence I posit the answers to the questions are a) very much yes b) yes c) n/a d) no.

NYC DOE is an incredible organization that serves both the extremely wealthy and the extremely needy. There are schools where the majority of families are millionaires and the quality of the education and attention is competitive with $50k/year private schools. But there is much, much more pervasive need.

Some estimates put 1/10 of the total attending population as homeless. 70% of the attending population are on some form of financial assistance.

The range of services the DOE offers are astonishing. For various reasons they do NOT include anything that constitutes medical care, but they will regularly run studies that involve making medical resources available or provide some medical intervention. The needs in some areas are so great. As an efficient deliverer of in person services, there is no better organization than the DOE.

It is very likely that most of the students in this study have never been- and never would otherwise be- to a dentist. They very likely get 1-2 meals a day from their school year round. They in many cases spend more waking hours in their school than at home. High poverty classrooms can be chaotic, but they often are much less chaotic than whatever home is.

Consent was collected, to be sure- DOE is extremely careful about this. DOE legal is extremely aggressive because they are often sued- mostly by students of means but also by advocacy organizations, of which there are many.

Very likely NYU was offered the option of where to do the study. They could have picked the Upper East Side or Tribeca- wealthy neighborhoods where kids will regularly attend boutique dental practices- but then what would they learn? The kids there are already getting sealants and so forth.

Second us. One of the most amazing things about New York is that it has a functioning school system unlike places on the West Coast.

Stuy, ps101, bx science are some of the best schools in the country

This is a bit of a silly take in my opinion. This bit, "The schools—which serve a racially diverse group of students, most of whom are from low-income families", sounds just like editorializing to me.

That is, it was just a test in NY public schools, not like they specifically sought out low income or underperforming schools, it's just that public schools in NYC have a much higher rate of low income families.

I don’t think it’s editorializing, there are plenty of school systems, public and private, that don’t fit this mold. My HS class had maybe 20 of 250 students whose families’ weren’t firmly middle class or above with a good 50 who came from the rich feeder school who were “new Mercedes for 16th birthday rich.” Realizing my family was lower-middle class was a bit of a shell shock for 13 year old me.

There's a long history of unethical research on people who are not well-equipped to do their own cost/benefit analysis, nevermind the famous cases where people were not even asked if they wanted to take part.

In elementary school in the 80s in upstate New York we had some sort of tooth treatment provided in the classroom, and it seemed like sort of a big deal at the time. Until recently I thought it was just a national program, until my wife told me she never had anything like it growing up in Rhode Island. Anecdotally I've had pretty good teeth my whole life and as far as I know, my friends from school have as well. Let's just say my wife is presently losing at Redneck Life (where the final score is number of teeth you still have at the conclusion of the game). :)

its certainly not this treatment, since my treatment was like 30+ years ago, but it was a treatment

If you read Weston Price's Nutrition and Physical Degeneration you will see that many tribes have PERFECT teeth without even flossing.

Tooth decay is purely caused by diet.

Certain grains also cause it, not only sugar.

Rice for example is very bad for teeth (90% of people damaged teeth, acidic starch is what they assume), while potatoes are much less harmful (~10% if I remember correctly, since potato starch is alkaline).

Sodas (anything with low ph) is terrible for the teeths as it seems.

So it's also not "just carbs", but there are other factors.

So "painting teeth" with dubious chemicals is moronic since the problem is the food. If the food destroys your teeth so much, think what it does on the inside of you which you cannot see.

Eg check out this study: TOOTH DECAY IN RELATION TO DIET AND GENERAL HEALTH NILS P. LARSEN, M.D

You still need this stuff while people's diets change, though - diets generally have a good amount of cultural, religious, and family ties and it takes time.

Then there is the entire issue of trying to change the diets of poor people at a time when places (like the US) aren't even making sure the folks at the bottom can get enough calories and nutrients nor are we making sure diabetics and others have a diet fit for them, let alone trying to make sure folks aren't eating badly for their teeth.

And I'm sure I'm not considering things like changing the crops being planted and things like that.

But we have this stuff, perhaps. It isn't moronic considering we probably aren't going to change diets suddenly.

Yeah but maybe unwinding 10,000 years of agriculture isn't very feasible.

Price didn't believe that carbs or grains caused tooth decay: he prescribed freshly ground grains for the diet.

Price's book is compelling evidence that something in modern societies causes tooth decay, which is unnatural.

Price's hypothesis was that it was caused by the change to the modern diet and its lack of nutrients. So white flour bad, freshly ground whole grain good. Refined sugar, which Americans still eat ~80 pounds of a year creates a nutritional deficit that is hard to over come since the rest of our diet is not nutrient dense.

I don't believe in rice causing bad teeth either. I live in Asia and almost all of my grandparents and great-grandparents have good teeth, and we only eat rice here. The ones who have bad teeth are, unsurprisingly, heavy smokers or drinkers.

After I had been on an all meat diet for a year I went to the dentist for a cleaning and the dentist called someone over to show them my gums, which were apparently unusually healthy.

> So "painting teeth" with dubious chemicals is moronic since the problem is the food.

This is a pretty bold claim to make -- given the reality of American diets, do you think there's a better option? Especially in healthcare (and especially with $$$ American healthcare) you have to balance the perfect solution with meeting people where they are.

It's also easy to say when you have the money to buy grass fed beef and other high quality food sources which I suspect most HN peeps have the income for. It's a lot like saying "let them eat cake if they're starving"

Potatoes are not alkaline. Potatoes and rice are close in ph and on the acidic to neutral side. The average pH of baked potatoes is around 6.0 to 7.0, while the average pH of cooked rice is around 6.0 to 6.5.

(7 is neutral, and values above 7 move toward alkalinity.)

> If the food destroys your teeth so much, think what it does on the inside of you which you cannot see.

I was with you until this point. The stomach is highly acidic. The natural next step food takes in our bodies is into an environment that would destroy our teeth. It does not necessarily follow that food which damages our teeth is bad for the rest of us. If anything, your potato/rice examples would suggest that the opposite is true.

I agree tooth decay is largely a result of our diet, but that doesn't mean we have to change our diet to reverse/prevent tooth decay. I have a garbage diet and still manage to keep my teeth okay. I'm not in a rush to overhaul how I interact with food.

> So "painting teeth" with dubious chemicals is moronic since the problem is the food.

Moronic! Why do this simple intervention when we could simply get everyone to completely change their diets, removing every staple food their family has been cooking with for generations? Obviously the latter is much more practical.

Sounds awesome. I’ve never heard of this before, but from some quick googling it looks like there are some pediatric dentists around who already offer it.

Are there other important new preventive measures to know about?

Titlegore

> Silver diamine fluoride, as well as sealants, protected against cavities

"kept 50% of cavities from worsening when children were seen two years later."

Wait, they let kids run around for two years with untreated cavities?

This has been "known" for 30 years. It needs to be mandatory.

And take vitamin K2 for your teeth (and bones and arteries).

Is there any company working on "cloning" or growing teeth? That way we don't have to worry about cavities or root canal any longer? When I was a kid, I was sure we'd have this tech by now. How hard is it to grow teeth?

Good oral hygiene is all that is needed, and (in the UK, at least) we've been mostly failing at this basic level of common sense prevention for eternity.

I guess it's the same for dieting, people looking for magic solutions when the simple answer is to eat less.

Between people looking for magic solutions and other people deriding the masses for being lazy... yeah, not much room left in the field for learning and growth.

I do agree there is something to pushing for a bit more hygiene for things. That said, I also think there is something to be said for looking at the items holistically. To wit, I'm not brushing my pet's teeth every night, and I have yet to ever have one that needed intervention due to cavities. Especially not in mid life. I know some folks that have, of course. So, it isn't like it is completely unheard of in the animal kingdom. I'm curious why it is so different for us, though. Would love to see a good treatment of that topic.

I'm sure you already know that your pets don't consume much sugar and that's the main reason they don't get cavities?

Maybe humans will, eventually, evolve to a state where our teeth renew themselves naturally, without intervention? Who knows?

I mean, you aren't wrong. They also eat a lot of really hard to chew things that scrape at their teeth and gums. And, I'm sure, breeding selected for pets that don't have massive teeth problems.

That is, I get it, very complex topic. You can see other similar "patterns" that are of little help in the animal kingdom. See a "fat" animal, and it is almost certainly one that doesn't eat meat as a primary nutrient source. Similarly, lean animals are typically predators. Would be a fallacy to think you have to be a meat eater to be lean, though.

The topic that has been intriguing to me lately, is the link between mouth breathing and poor oral health. So many topics that we don't know nearly as much about as we want individually. Much less all mixed up together.

Pets get other stuff though. My understanding for cats at least is there's a heavy genetic component. I have two brother cats and one has bad teeth [1] and one has good teeth. But they eat the same and get their teeth brushed the same.

[1] As in, he lost one and needed his teeth cleaned by age 7 (not old). That said, I didn't get into a habit of brushing their teeth until they were several years old, and both of their teeth are excellent now (vet doesn't see either of them as needing a cleaning in the foreseeable future). So dental hygiene is helpful even for cats!

7 is fairly old for cats, I thought? Not ancient old, but well past early life.

I fully agree on it having a hefty genetic component. Pure breed?

My cat is 14 and has never had a cavity and she pretty much just eats high quality dried food along with a bit of canned food every day. Not pure bred, she's a mutt.

Wasn't my intent on that. I was thinking in comparison to elementary school kids. Also just curious, all told.

My expectation would be that mutts have healthier teeth. And general health. That said, that expectation isn't strong enough that counter would shock me.

I'd say it's neither old nor young. I believe it's like the 30s/40s of cats.

My cats are also pretty healthy otherwise - they're even older now and the vet always says she'd believe it if I said they were 5 by their muscle tone etc.

This is what I intended "fairly old" to be. The framing of the article was about grade school kids, so I really just meant well above that age. :D

haha that's fair

I think the gist of all this is "brush your teeth"!

Allot of what most people consume isn't great for teeth. Like coffee (and some teas).

Other animals don't eat nearly as much sugary food, or food of a sort that tends to get stuck in your mouth (non-processed food like corn on the cob can do so, but even that's a product of domestication and not so widely eaten by other animals - our dog loves it, but canine teeth are spaced further apart and shaped in such a way it's less likely for bits to get lodged between them. Also I gather dogs at least have much more powerful anti-bacterial agents in their saliva.)

The food that gets the most stuck in my teeth is meat. Pretty much period. Close second will be stringy vegetables.

Which is to say, you aren't really wrong. But it is clearly more nuanced. I put a longer response to another post. I am not trying to find a single answer here. If we are lucky and there is one, I'm all for it. But, in general, I am very skeptical of many of these simplistic answers.

Meat and stringy stuff gets stuck between teeth, not to teeth. It's the stuff that sticks to the teeth, provides cover and environment for bacteria to grow is (a big part of) the problem. The things that are actually stringy are usually easy to remove. Things that stick to the surface - less so.

The thing that typically gets stuck to teeth even with a good diet are minerals found in saliva.

As someone that doesn't have any cavities, I'm well aware of many of the subtle points. I also am well aware of just how scatter shot so much advice is... And how dominant genetics can be in this.

Celery in my case.

I'd hazard that cooked meat is more likely to have that issue than raw meat. And as another poster pointed out, it's possibly more relevant what food sticks to the outer surface of your teeth, though I'm pretty sure any source of food around your teeth that bacteria can grow on is likely to lead to cavities.

"Other animals"

Most other animals (at least mammals with teeth) don't live as long. Many do suffer from dental issues if untreated. For example, horses may live into their 30s in domestic settings, which include dental care. Wild horses typically live 15-20 years. If they survive other perils, one of the causes of their earlier death can be starvation or malnourishment due to not being able to chew their food.

Yeah. I tried hinting at that in my first post. Pets will have teeth issues as they get older. Much of that comes from nutrition learning, though.

Humans seem particularly prone to midlife tooth issues. With the obvious caveat that humans also are prone to ignorance dominating the things we believe. :)

Sure, but humans often have issues with cavities well before even reaching adulthood.

I think this is a pretty reductive take, both for dental and dieting.

There are a lot of reasons a person might not be able to take care of themselves very well, and we should certainly try to make it easier for them, rather than just dismissing it as a solved problem and a moral failing of anyone who runs into issues.

Good oral hygiene is only fixing one reason for needing replacement teeth. Artificial replacement remains subpar and causes gradual erosion in the jaw that will catch up with people who have accidents early in life.

Can’t just clone them. Gotta grow them in your mouth with stem cells.

So why can’t we do that yet?

Maybe it’s an economic curse. Wealthy people tend to have good teeth. Sure, here and there a cavity. But the bulk of the market for new teeth is probably poor.

Teeth aren’t exactly the top priority but stem cell research could regenerate vital organs. It’s very much an area of active research. It’s just hard.

Only because they tend to have much more aggressive parents about teeth health, going to the dentist, etc. it has nothing to do with being rich, even the lowest 10% in income can afford toothpaste and a toothbrush which you can probably get for free. The problem is that it's low on the list of priorities.

Even if it was invented it would be super expensive.

I've always half-wondered if wisdom teeth could be saved. Either for re-insertion. Or as the source for the required stem cells for regrowth.

I mean, evolutionarily, the late appearance of those teeth were probably to replace broken molars?

If you get 95% of your calories from hunting you will spend a lot of time chewing tough pieces of meat. Kids who grow up chewing meat and gnawing on bones develop larger and wider jaws (and more attractive faces) and they have space for wisdom teeth.

They often get broken up on removal, from the videos I've watched. So not sure how useful that would be

It seems like I've been hearing for the last 40 years that tooth-re-growing tech was just around the corner, and in five years none of us would have to worry about dental problems anymore.

Still waiting.

Soon I'm going to have to break down and buy a toothbrush.

It’s clearly not a simple process with very particular behaviors, but i agree, based on current knowledge of teeth it seems like this should be in reach for humanity.

Seems like we've been able to grow human teeth in mice and other lab animals for over a decade. How far away can we be from trials in actual humans? I'd sign up without hesitation, even if there were substantial risks.

two things..

1. that flaccid teeth meme

2. sharks teeth

i would be comfortable with having a fresh set of teeth every other year or 3 or 5 years later. It would mean i could be a little bit more lazy and/or not have to "SUFFER". i hate that, the teeth are the worst

There has been some work, nothing commercialized yet that I've heard of:

https://www.nextbigfuture.com/2018/02/dentists-may-soon-comp...

https://www.engadget.com/2016-07-03-regenerative-tooth-filli...

https://www.nottingham.ac.uk/news/pressreleases/2016/july/fi...

https://soylentnews.org/article.pl?sid=16/07/28/0228219

I've seen a report on PubMed about a successful growth of a new replacement tooth from stem cells in a rabbit as well, can't find the link at the moment. This seems to be a summary of a lot of different research on regrowing teeth, and it states up front that only regrowing enamel seems to be on the near horizon:

https://dentalfreak.com/teeth-regeneration-and-regrowth-curr...

It seems SDF was approved for kids 7 or so years ago in the US:

https://soylentnews.org/article.pl?sid=16/07/18/0057230

SDF is used on the very old a lot also (much easier to use for those with Alzheimer's for example). You can ask for it but not a lot of US dentists have experience applying it or keep it in stock. Some dentists will adamantly refuse to apply it, probably because it reduces their profit since if it stops decay there is no filling needed, though it could also be because it can cause staining in unpredictable places (anywhere with decay, and the gums also) that takes months or years to disappear. In general it would seem the dental profession has no reason to welcome a cure for tooth decay and every reason to delay one. It would not put them them entirely out of business, but it certainly would reduce business.

There have been some other interesting developments in dentistry:

https://munewsarchives.missouri.edu/news-releases/2011/1220-...

https://nanovabio.com/

https://www.sciencedaily.com/releases/2012/01/120104115106.h...

https://www.nytimes.com/2016/08/30/upshot/surprisingly-littl...

The sterilizing cold plasma torch is already being used in some surgeries I believe.

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