
Don't rinse with water straight after toothbrushing - pierlu
https://www.nhs.uk/live-well/healthy-body/how-to-keep-your-teeth-clean/
======
f0ok
From "Potential fluoride toxicity from oral medicaments"
([https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5651468/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5651468/)):

"The beneficial role of fluoride for the maintenance of good oral health has
been known for many decades and strongly evidenced by scientific research.
However, it must be emphasized that tooth decay (dental caries) is not caused
by fluoride deficiency and fluoride supplementation will never reverse the
active or gross carious lesions. Since the level of safety of fluoride is low,
products that contain a high level of fluoride should be stored and used
according to the recommendation and should be monitored by a qualified dental
professional especially in children and pregnant women. In children, the
swallowing reflex is not very well developed and the fluoride containing
dental products are flavored hence increasing the possibility of a child to
consume an excessive dose of fluoride."

Maybe swallowing fluoride is not such a good idea?f

(Also, can someone compare toxicity levels of lead versus fluoride?)

~~~
crooked-v
Most toothpaste has about 1000 ppm of fluoride (0.1%), which isn't a "high
level" \- in fact, it means that one blob of it on a toothbrush has about the
same fluoride content as a large glass of fluoridated water.

"High level" in this case comes in with fluoride rinses or specialty
toothpaste, which can have 5000+ or 10000+ ppm of flouride.

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xenospn
So I'm supposed to leave the toothpaste in my mouth? For how long?

EDIT: I'd also like to point out that I have been rinsing my mouth after
brushing for the last 40 years, never used mouthwash, and never had a cavity.

~~~
rococode
I'm not sure if this is correct but when I was in college I noticed a couple
guys who just spit and didn't rinse at all. Like, ever. They just brush, spit
out some toothpaste, and then move on to the next step of their routine.

At the time it seemed kinda freaky to me since I always rinse the toothpaste
out when I finish brushing, but maybe they were doing it right... I can't get
over the feeling over toothpaste stuck in my mouth, though. Perhaps it's one
of those things that's hard to change once you establish a pattern in
childhood.

~~~
ianai
If it kills the bacteria on your mouth that’s got to hurt your gut too.

~~~
TheAdamAndChe
It's not about killing bacteria, its about leaving fluoride ions in a slightly
basic or at least nonacidic environment for long enough to convert
hydroxyapatite to fluorohydroxyapatite. This chemical reaction takes time, but
considerably strengthens your teeth against corrosion and prevents cavities.

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stygiansonic
Also from the article: " _It 's best to floss before brushing your teeth._"

~~~
zzleeper
Why? I would have thought it makes more sense to brush, then floss, then wash
at the end so the fluoride stays longer

~~~
jackewiehose
I always thought that flossing mostly moves the dirt from between your tooth
to another side. So I always brush after flossing.

(I also never thought about fluoride so of course I rinse after brushing and I
will continue to do so because otherwise it would be very uncomfortable)

~~~
whalabi
As far as I know a function of flossing is to disrupt bacteria in places that
your brush can't reach.

Presumably another is to dislodge food stuck there.

I can imagine that floss + rinse would accomplish both well enough, especially
if it's twice a day (but surely most people brush one a day)

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latortuga
I use a toothpaste for sensitive teeth due to some recessions (due to hard
brushing, don't push so hard kids!) The dentist and manufacturer of the
toothpaste both recommend you don't rinse post-brush to ensure the numbing
agent stays on your teeth.

~~~
climb_stealth
I can very much recommend an electric toothbrush against brushing too hard.
Depending on the model it lets you know when you push too hard. It has helped
me a lot.

Also, according to my dentist the receded gums don't grow back which is quite
scary.

~~~
mrsaint
Oh, but you can grow it back through a gun graft, and I had it done
successfully. Healthy gum tissue is removed from the roof of the mouth and
uses to build the gum back up where it has receded.

~~~
orev
And it is an extremely invasive and painful procedure that should be avoided
at all costs if you can. And if you don’t change your habits, you’ll have to
have it multiple times.

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staplung
Note that the rationale is that it washes out most of the lingering fluoride,
which is presumably more of a concern in the UK where the water isn't
fluorinated.

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asdff
In the US, drinking water supplemented with fluoride for this very reason, so
feel free to rinse out your dislodged food scraps after brushing and ignore
this advice from the NHS.

~~~
noname120
Do you have more information on this? I thought that fluoride was toxic and
thus shouldn't be swallowed. Are the quantities too small to harm you yet
sufficient to prevent the formation of caries?

~~~
crooked-v
Water fluoridation rates are well under dangerous levels - about 0.7 mg/L for
artificially fluoridated water, vs 2+ mg/L long-term to actually cause any
problems. Even that small amount helps with reducing tooth decay, as was shown
in the US in studies starting in the 50s comparing areas with naturally
fluoridated water with areas without it.

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gumby
Interesting advice. Also interesting that it used inches rather than metric.
Is that common?

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mdesq
That's why my dentist recommends a fluoride mouthwash after brushing.

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avocado4
My routine:

1\. Floss 2\. Waterpik (water + mouthwash) 3\. Electric brush, no rinsing

~~~
luckydata
waterpik should do the job of flossing already, you can probably skip step 1,
at least according to this study:

[https://www.ncbi.nlm.nih.gov/pubmed/24282867](https://www.ncbi.nlm.nih.gov/pubmed/24282867)

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gwilliams
This advice ought to be printed on every tube of toothpaste.

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kalium_xyz
>Don't rinse your mouth immediately after brushing, as it'll wash away the
concentrated fluoride in the remaining toothpaste.

That is the point.

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sillysaurusx
It's weird that we don't know what teeth were like before fluoride was
invented. The knowledge isn't directly accessible to everyday people. Sure, we
know some examples, but what about the averages? Was everyone's teeth just
completely screwed, all the time? How could evolution work that way? We need
our teeth to eat.

It's further complicated by the invention of processed sugar, which ruins
teeth. Before that, _presumably_ it wasn't quite as bad to live without
fluoride. But again, the knowledge seems kind of hard to find.

Anecdotally, I lucked out by not listening to a dentist when they said one of
my teeth had to come out. Still have it six years later, and it's fine.
Apparently it was a rather intense toothache that eventually went away.

~~~
crooked-v
> Was everyone's teeth just completely screwed, all the time?

Well, often, yes. See, for example, the history of pre-modern dentures, which
were common for people in only their 30s and 40s (George Washington's teeth
all fell out before he even reached 30!).

> How could evolution work that way?

Two reasons:

First, if you've had children, you're surplus material. Most people throughout
history who have had children have done so by the age of 30 or 40, and so
after that, their teeth just don't matter, evolution-wise.

Second, humans evolved in an environment with very limited access to sugar and
acidic foods. Sugar and acidic foods are the main cause of cavities, and have
been common since the invention of civilization and extremely common since the
advent of mass industrialization.

> Still have it six years later, and it's fine.

It's probably not fine. It's entirely possible to have teeth that are
apparently pain-free right up until they literally snap in half from deep
cavities.

