The Order Nobody Told You Mattered

Ask a room of people whether they floss before or after brushing and most will look puzzled, because it hasn’t occurred to them that it’s a question.

It is, and one dentist answering publicly explained their own order and the reason for it:

I do floss before brushing so that the bristles of the brush can clear away debris which has been loosened by the floss. r/AskReddit

That’s the argument in one sentence, and it’s a good one.

Why first makes sense

Flossing dislodges. It breaks up plaque on the flat sides where two teeth touch and pushes debris out of the gap.

If that happens after brushing, the loosened material is sitting in the mouth at the end of the routine, and the usual reflex is to rinse it away — which also rinses away the fluoride film that was the point of brushing.

If it happens first, the brush sweeps that material out, and more importantly the toothpaste reaches surfaces that were blocked a minute earlier. Fluoride works by contact, and it can’t contact what it can’t get to.

So the order isn’t about tidiness. It’s about which surfaces the active ingredient ends up touching.

The same dentist on how little most people actually do

Worth quoting because it recalibrates what “good enough” means:

Most people don’t floss at all and brush for about 30 seconds if they honestly time it. r/AskReddit

Thirty seconds against a recommended two minutes. And a warning that arrives in the same breath, which matters more than the order ever will:

More pressure is not a substitute for the length of brushing time. Hard brushing is bad for gums. r/AskReddit

Time, not force. People who feel they’re not doing enough almost always press harder rather than brush longer, and pressing harder is the one adjustment that actively causes damage.

Water flossers, honestly

This comes up in every thread, and the honest answer is neither of the two answers people want:

I always say it’s better than nothing, but not really a substitute for flossing. Plaque is very sticky and the waterpik removes the loose debris, sure, but not the plaque. r/AskReddit

That’s the distinction. Debris rinses. Plaque adheres. A jet of water is very good at the first and only partly good at the second, because plaque is a film stuck to a surface rather than a crumb sitting in a gap.

Which does not make it useless — far from it. For anyone with braces, bridges, implants or a bonded retainer, a water flosser reaches places string cannot. And for anyone who will not use floss, the comparison isn’t floss versus water. It’s water versus nothing.

Somebody in another thread described switching and being surprised:

It does. After using it for of week or so, I used the normal floss again, and almost nothing! r/LifeProTips

The mouthwash confusion is the expensive one

Order matters far more here, and almost everyone has it backwards because the bottle tells them to:

Unless the mouthwash says to be used last, which mine always have. I buy mouthwash with fluoride. r/AskReddit

Reasonable, and it’s what the label says. The problem is arithmetic: toothpaste typically carries around 1450 ppm of fluoride, and mouthwash often carries 100 to 225.

Rinsing with mouthwash after brushing swaps a strong dose for a weak one, and washes the strong one down the drain.

The same person came back and corrected themselves, which is the most useful thing in the whole thread:

I wanted to edit this to clarify that further downthread I was corrected, as some toothpaste brands do say to leave the toothpaste on your teeth so it works better. r/AskReddit

If you like mouthwash, use it at another time of day. Not chasing your toothbrush.

The order that follows from all of this

Floss. However you’ll actually do it — string, picks, interdental brushes, water.

Brush two minutes, gently, soft bristles. Time it once to find out what two minutes actually feels like, because almost nobody’s estimate is right.

Spit. Don’t rinse.

Nothing to eat or drink for about half an hour.

Mouthwash at a different time, if at all.

The short version

The order is worth getting right, and it’s worth almost nothing compared to doing it at all.

Floss first so the brush can clear what came loose, and so the fluoride reaches what the floss just opened up. Then leave it alone.