Federal health expert drop flossing from health guidelines • Hacker News Board

Re: Federal health expert drop flossing from health guidelines

#171

Post by fpgaminer » Wed, Aug 03, 2016, 7:29 PM UTC

hashkb wrote: post #141

Vexs wrote: post #131

Personal antecedent is that I never flossed for 18 years, and would always walk out of the dentist with a bleeding gum somewhere in my mouth, and my teeth would hurt drinking cold water, etc, but when I finally started flossing all those problems evaporated. Some mouths probably need it more than others, and it appears that mine is one of them. Is flossing the best option for inter-teeth cleaning? Maybe not. However,…

You floss after brushing? I always thought the reverse was the best practice. Of course... there has been zero science, so maybe the best is brush -> floss -> brush -> Listerine -> floss.

I am not a dentist, but based on my understanding (derived from reading commentaries by dentists) the "best" would be floss -> brush. Never mouth wash (except when recommended by your dentist for specific conditions).

That's derived from the idea that brushing is not about cleaning the teeth. It's about disrupting bio-films and depositing fluoride on the teeth. That's the reason why dentists recommend not rinsing your mouth after brushing. If brushing were about cleaning then clearly you would want to rinse to remove everything from your mouth. But since brushing is more about applying fluoride to your teeth, it makes more sense not to rinse as that would remove all the fluoride that you just worked to apply. (The recommendation is to brush, then take a teaspoon or two of water into your mouth to form a toothpaste slurry, swish around, then spit.)

I thus argue that flossing should come before brushing because flossing would remove the food from between your teeth, allowing fluoride to penetrate those areas.

And with regards to Listerine/mouth wash, the alcohol based stuff causes mouth cancer and hasn't shown any benefit to the reduction of cavities (I don't recall its effectiveness with respect to bad breath or gum disease). There is fluoride based mouthwash, which dentists do recommend to certain patients, but for most people there's no point since they're getting all the fluoride they need from the toothpaste. And of course there are mouth washes medicated for specific conditions, which again will be recommended by your dentist when needed.

Re: Federal health expert drop flossing from health guidelines

#172

Post by mikeash » Wed, Aug 03, 2016, 8:06 PM UTC

MicroBerto wrote: post #169

mikeash wrote: post #147

Earlier quoted context omitted.

Many chiropractors will also claim that they can directly observe the much lower incidence of cancer and heart disease in their patients, but that doesn't make it true.

Not relevant given that chiropractors are making money off said claims, and dentists are not. Dentists stand to make less money when their patients take care of their oral health with something that costs literally a penny per day.

People aren't automatically wrong just because they state something in their interest, nor are they right just because it's not. To me, the important difference between the two is that dentists can explain the basis of their recommendations in terms that make some sort of sense, whereas the mechanisms proposed by chiropractors are clearly nonsense.

Re: Federal health expert drop flossing from health guidelines

#173

Post by mcguire » Wed, Aug 03, 2016, 9:04 PM UTC

MicroBerto wrote: post #170

mcguire wrote: post #92

Earlier quoted context omitted.

I hate to do this, but...source?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3898367/ Gist is that tongue cleaning yields less bacteria (that's one major cause of bad breath), but they still recommend both brushing and tongue cleaning since the reduction of tongue bacteria didn't reduce plaque. I never claimed that it did though. Tongue scrapers are cheap and awesome. It's amazing what kind of disgusting stuff you'll scrape off that thing. I'll nea…

Thanks!

Re: Federal health expert drop flossing from health guidelines

#174

Post by pizza234 » Wed, Aug 03, 2016, 9:56 PM UTC

flukus wrote: post #7

pizza234 wrote: post #6

Earlier quoted context omitted.

Anecdote is not evidence. A few people are certainly "gifted" teeth-wise (I know another case), but not going to the dentist for 25 years would be disastrous if applied on large scale.

>Anecdote is not evidence. Well that's the problem, we don't have better evidence.

The sentence above was about considering the extreme case irrelevant.

Focusing on flossing itself, as person who started doing it regularly only as adult, I think that researching on how frequently one should floss (or not) is in a way like researching how frequently one should change underwear. It may make sense theoretically, but ultimately all it requires is just to pay attention.

I never noticed the bleeding and/or irritation of the gums (which dentists always mention) until I started flossing regularly.

Now I do feel a difference (as a matter of fact, I floss irregularly, depending on how the gums feel). Of course, I'm pretty sure I could survive without flossing at all.

This is in line with what dentists generally suggest. Given that flossing can be ultimately considered as simply extra cleaning, and that the presence (or not) of the effects can be easily observed, a couple of weeks of flossing should be enough for anybody to make a solid judgment more than any theory.

Re: Federal health expert drop flossing from health guidelines

#175

Post by nextos » Wed, Aug 03, 2016, 10:08 PM UTC

greggman wrote: post #132

nextos wrote: post #65

Earlier quoted context omitted.

There's a ton of evidence in the literature supporting that gum disease and cavities are, obviously, a bacterial issue. Flossing is an obvious way to disrupt pathogenic bacterial colonies by abrasion. I think irrigation is much better, as it reaches deep pockets below gums. But it doesn't replace flossing entirely. Those two, coupled with regular brushing of teeth, gum and tongue, plus oral probiotics should keep iss…

Where is this research that flossing is "an obvious way to disrupt pathogenic bacterial colonies by abrasion". Here's some research that claims flossing actually causes problems. "Dental flossing can produce bacteraemia in periodontally healthy and periodontally diseased individuals at a rate comparable with that caused by some dental treatments for which antibiotic prophylaxis is given to prevent IE." http://onlinel…

Thanks. This is a good point, which I agree on.

But in general, interdental flossing is very good against contact cavities [1]. Perhaps deep flossing is leading to bacteraemia. I have always found hard and awkward to perform deep flossing, and that's why I use oral irrigators instead. However, maybe irrigation also leads to bacteraemia. I've seen some references supporting that too.

[1] http://jdr.sagepub.com/content/56/6/574.short

Re: Federal health expert drop flossing from health guidelines

#176

Post by bytefactory » Wed, Aug 03, 2016, 10:55 PM UTC

fpgaminer wrote: post #171

hashkb wrote: post #141

Earlier quoted context omitted.

You floss after brushing? I always thought the reverse was the best practice. Of course... there has been zero science, so maybe the best is brush -> floss -> brush -> Listerine -> floss.

I am not a dentist, but based on my understanding (derived from reading commentaries by dentists) the "best" would be floss -> brush. Never mouth wash (except when recommended by your dentist for specific conditions). That's derived from the idea that brushing is not about cleaning the teeth. It's about disrupting bio-films and depositing fluoride on the teeth. That's the reason why dentists recommend not rinsing you…

Goddamn it, my dental hygienist told me to use mouthwash after brushing + flossing :(

Re: Federal health expert drop flossing from health guidelines

#177

Post by joshschreuder » Wed, Aug 03, 2016, 11:32 PM UTC

bytefactory wrote: post #176

fpgaminer wrote: post #171

Earlier quoted context omitted.

I am not a dentist, but based on my understanding (derived from reading commentaries by dentists) the "best" would be floss -> brush. Never mouth wash (except when recommended by your dentist for specific conditions). That's derived from the idea that brushing is not about cleaning the teeth. It's about disrupting bio-films and depositing fluoride on the teeth. That's the reason why dentists recommend not rinsing you…

Goddamn it, my dental hygienist told me to use mouthwash after brushing + flossing :(

I'd probably listen to someone with actual dental training over someone who opened their comment with "I am not a dentist" :)

Re: Federal health expert drop flossing from health guidelines

#178

Post by Mathnerd314 » Wed, Aug 03, 2016, 11:34 PM UTC

fpgaminer wrote: post #171

hashkb wrote: post #141

Earlier quoted context omitted.

You floss after brushing? I always thought the reverse was the best practice. Of course... there has been zero science, so maybe the best is brush -> floss -> brush -> Listerine -> floss.

I am not a dentist, but based on my understanding (derived from reading commentaries by dentists) the "best" would be floss -> brush. Never mouth wash (except when recommended by your dentist for specific conditions). That's derived from the idea that brushing is not about cleaning the teeth. It's about disrupting bio-films and depositing fluoride on the teeth. That's the reason why dentists recommend not rinsing you…

My understanding is that, although possible, if the cancer risk does exist, it's very small; here's an article placing it at 3-4 cases per 1,000,000: http://aaem.pl/fulltxt.php?ICID=1011054 (They cite a 2012 meta-analysis which showed no statistically significant effect of mouthwash) Here's a recent large-sample statistical study: https://healthcare.utah.edu/huntsmancancerinstitute/research... They find an 1.15 odds ratio of cancer for mouthwash users, but in the non-smoking non-alcohol-drinking cohort this effect goes the opposite direction (OR 0.83); statistics is hard and there isn't high-quality data to give a real conclusion. But since the overall incidence of oral cancer is roughly 1 in 10000 (http://www.nidcr.nih.gov/DataStatistics/FindDataByTopic/Oral...) I wouldn't be too worried; all these show is that the effect is tiny. (Of course, if you only remember the big headline from ten years ago with a tiny sample size...)

There's a clear line of research showing benefits in mouthwash: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4948552/ It's true that the fluoride in mouthwash does little, and there are some stupid mouthwashes that don't have any real ingredients, but essential oil mouthwashes (like Listerine) and several others (as mentioned in the review) have been shown to have significant gum benefits.

There's also some interesting research with tetrapotassium pyrophosphate and tartar buildup: http://periogen.com/periogen-studies.html Although I expect these studies are manufacturer-funded and thus overstate the effect, it seems pretty hard to deny that it helps.

Note: I'm not a dentist either, but I read this book my dentist recommended: https://amzn.com/B009LPLMRU. It's well-referenced for everything except water fluoridation and her conflict of interest (xylitol products).

Re: Federal health expert drop flossing from health guidelines

#179

Post by kristianp » Thu, Aug 04, 2016, 1:04 AM UTC

mattkrause wrote: post #157

vonmoltke wrote: post #125

A better discussion about the lack of evidence for flossing: https://www.sciencebasedmedicine.org/may-the-floss-be-with-y... Basically, yes, flossing helps, but self-flossing really doesn't do anything more than just brushing daily. I'm a little disappointed at the number of comments here along the lines of, "Well, it's obvious! Why do we need to study it?" That's a very unscientific attitude.

I had the opposite reaction: how on earth has no one looked into this!? But if you dig into it, it's horrifying how little "evidence" goes into treating a lot of common medical conditions. For another trivial example, the stuff in Sudafed PE (phenylephrine) http://www.sciencedirect.com/science/article/pii/S1081120610... is much worse than the psuedophedrine it replaced. I wish the NIH (and other funding agencies) wou…

What are the phases in this study? There's no explanation of the phases in the abstract:

"Phase 1 results showed a difference between phenylephrine and placebo that was 64% of the difference between pseudoephedrine and placebo, substantially greater than the 17% difference observed for all phases. "

Edit: Phase 1 may mean "Testing of drug on healthy volunteers for dose-ranging", from wikipedia:

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

Here's the paper:

http://www.vcc.at/documents/get/47/A%20Placebo-Controlled%20...

Re: Federal health expert drop flossing from health guidelines

#180

Post by deelowe » Thu, Aug 04, 2016, 1:56 AM UTC

mikeash wrote: post #146

robbiep wrote: post #98

Earlier quoted context omitted.

Your argument is a slippery slope for the acceptance of every kind of pseudoscience. How do we know something is 'obviously' good for you without research? NOTHING Is so cut and dry that you can make that statement. For example: organic food. Obviously, must be amazing for you. Got two great buzzwords in it: organic and food. Therefore, amazing for you. Does the research bear this out? Similarly, homeopathy, reiki, p…

Has anyone done the research on the health benefits of rubbing broken glass in your eyes twice a day? Somehow I doubt it. Would you say that we know nothing about it? Personally, I am quite happy to accept based purely on common sense and intuition that this is unlikely to be healthy. Research is just another tool. It happens to be a really good one, and when research contradicts common sense and intuition, research…

> health benefits of rubbing broken glass in your eyes twice a day?

I'm sure there are plenty of medical journals documenting the effects of getting abrasive substances in your eyes.