If you want to avoid tooth infections, the #1 thing you can do is stop eating sugary food / drinking alcohol or sugar water; for a more complete caveman approach, cut back on other starchy foods like rice, bread, and pasta. The #2 thing you can do is occasionally visit the dentist for a checkup or whenever your teeth give you trouble. The #3 thing you can do is occasionally apply topical fluoride (it’s not clear what difference there is between drinking fluoridated water, brushing weekly, brushing daily, ...). Getting a nutritious diet is also probably important.

Our modern culture taboos anything less than brushing multiple times per day, but it’s not clear how reliable the evidence is supporting this as a blanket requirement (the studies I’ve seen had many other confounding variables, but admittedly I did not do an exhaustive literature review), and most of the tooth infections probably result from other causes.

There are people with perfect teeth who brush rarely, and people with frequent caries who brush religiously after every meal. On average, hunter–gatherers have better teeth than people in agricultural societies, including modern ones. They don’t have access to oral surgery, so when things go bad they can go very bad. But that’s not really related to brushing.

> Our modern culture taboos anything less than brushing multiple times per day, but it’s not clear how reliable the evidence is supporting this as a blanket requirement (the studies I’ve seen had many other confounding variables, but admittedly I did not do an exhaustive literature review), and most of the tooth infections probably result from other causes.

I've heard so much conflicting information on this... Off the top of my head:

* Brushing too often - such as three times a day - speeds up erosion

* Or, that only happens if you brush too hard

* Or, that brushing too hard doesn't affect the teeth, that that's just confusion with it affecting the gums

* Or, that it has nothing to do with duration or hardness, but rather, how soon after eating that you brush (something about the extra saliva for food causing a slight weakness that takes an hour or so to go back to normal)

* Or, that leaving food residue in the mouth for any duration - such as that hour in the last case - causes saliva and bacteria buildup that speeds up erosion

My dentist the other day said "oh you're right handed."

I said "how did you know?"

She said "because that makes it easier to brush the left side of your mouth. Which is why your gums are really eroded on that side, and perfect on the right side."

She could just say that to every patient and she'd be right most of the time ;-)

I just water floss now. I don't think any amount of brushing can come near the ability to clean teeth like pressurized water...

One of the most important things is to get the appropriate toothbrush, ie. one that says "soft". Not "hard" or even "medium", because while those feel like they would be more effective, they are much too harsh on the gums even the enamel, over time. They also force you to apply a lot of pressure if you want to clean between the teeth, adding to the damage.

A soft toothbrush using in small circular motions is best. And for the love of all that is holy, floss!

The trick is that it doesn't really get worse after a couple of days.

If you stop brushing your teeth for a week, that's about the final state (unless you eat lots of sugary things which actually break your teeth).

Same thing for showering. At some point you stop getting stinkier.

Anecdotal, but I drink a beer in bed after brushing my teeth. No cavities in 39 years. I figure there is no sugar in the beer.

You have one heck of smart mom.

But the argument is kind of stupid. It would have made a little sense if she said something like "Cave men didn't ate candy bars" or something like that..