I've also heard that early modern humans had fairly good teeth for their age despite the presumed lack of dental care, presumably also due to differences in their diet from us.

Either some leap of logic or information is missing there or you're drawing the wrong conclusion from your data

You know how dentists say "Hey, I can tell you drink a ton of soda, you need to stop"? I would get told this every time I'd go in for a cleaning, despite not drinking any soda and very little fruit juice/other sugary drinks for many years, 90%+ water only.

Fast forward 20-something years, and 2 of my daughters have had to undergo a dental rehab similar to mine at very young ages (though not quite as young as me), despite the stringent dental regimen my wife enforces to prevent this fate. There's no doubt that they got my bad teeth genes.

We're talking young kids here, ages 2-3 at the time of the operation (I was 18 mos. when I went down). They don't eat an inordinate amount of sugar, and as I stated above, my wife is very thorough with their dental hygiene. The water is fluoridated where we live. A lot of kids this age surely have much worse diets and much worse dental hygiene, but their teeth seem to be problem-free for many years.

Personally, I've had tons of fillings, 7-ish root canals, two teeth fully extracted because they were past saving, and several that badly need work and I'm not even 30 yet. Pretty much the only people living with worse teeth are opiate addicts.

I hope I win the lottery some day so I can get a mouth full of implants and be done with it. I hear the going rate for this is about $75,000.

A lot of people refuse to believe that genetics play any role, but that's absolutely not consistent with my experience, nor the opinion of most of the dentists I've had.

My parents enforced our dental care and we went to the dentist regularly when I was young. Always once a year checkup and twice a year cleaning and still I had regular dental issues.

In the second grade I can recall being brought out of class to a tooth-care specialist the school brings in to teach kids who seem uncared-for to brush their teeth. I brushed twice a day.

When I was fifteen I remember being yelled at by my dentist about how I don't look after my teeth because I had "16" cavities (the dentist, mind you, in my later years I realized was actually a bit of a hack -- all of his work fell out of my mouth and left me in terrible pain).

Around this time the dentist put me on regular fluoride mouth washes -- I went home with a bottle of some god-awful "cherry" flavoured stuff. I _still_ had repeated problems.

Fast forward to the present -- I've had one infected wisdom tooth, one infected molar -- both had to be removed. I have one half-decayed wisdom tooth that will be extracted soon. This fall I've had to have 4 fillings (some of them were put off for a while mind you).

The next year I am pending a root canal and a crown, and my dentist also has informed me that (at age 30) I require jaw surgery or I face the possibility of regular migraines due to molar wear.

I floss, brush, and use mouth wash daily. I don't eat much sugar. My parents actually raised us on a lot of raw vegetables (my mother grew, and I was raised in rural southern Ontario in Canada -- something of a agriculture belt).

The only neglect would be that my parents could not afford braces when I was young.

There has got to be some genetic aspect. Or does Hacker News as a consensus believe in shit luck?

I think I first heard about them on HN. BLIS and K12 are the keywords, if I remember correctly.

Here's an article that reviews the literature on diluted bleach rinsing: http://www.rdhmag.com/articles/print/volume-35/issue-6/colum...

It depends on the natural amount of fluorine in the water, if there's sufficient, then it's fine.

It's only in the relatively few areas where there is a deficiency that it's a problem.

And of course it also depends on diet.

Offsetting your claim are studies which show that where people exclusively drink rain water, there is a higher incidence of tooth decay.

I'm not one of those "fluoridation is a government plot to make everyone pliable" crazies. Just saying that it's far, far more important to BRUSH YOUR TEETH than to have a fluoridated water supply. Just seems to me like water fluoridation is just one of those crazy things Americans and places America has influenced do (such as using the customary measure system and circumcising their male children - sure if you dig deep enough you can justify it, but plenty of people get along just fine without it)

Cavities do not form without cariogenic bacteria, provided with a food supply of simple sugars. If you have such bacteria, there are several ways to inhibit cavity-formation, such as by chemically hardening bioapatite with fluoride ions, or by re-mineralizing tooth enamel.

Communities would be better served by mutans eradication efforts, even though they could cost far more than the $1/person-year that fluoridation costs.

If I had the cash and political backing, I would put mutans-specific bacteriophages and tricalcium phosphate in a municipal water supply. I'd then subsidize dental office visits for persons in the affected area, such that anyone desiring fluoride treatments can get them at no additional charge, and offer gratis chlorhexidine/xylitol mouth rinse after every visit.

Kill the S. mutans; end cavities.

I think the point is that fluoridation is often unnecessary because of the natural amount of fluoride in the water.

That's not really true in and of itself -- fluoridation won't fix damage done by bad hygiene or diet. As someone else mentioned, genetics and other factors all play a part too.