How to Floss Properly: The Technique Most People Get Wrong

By Lovik Mirzaeian, DDS. Updated October 2026.

To floss properly, slide the floss between two teeth, wrap it in a C shape around one tooth, and gently move it up and down along the side of that tooth and just under the gumline. Then wrap it the other way and do the neighboring tooth. Most people skip the C shape and just snap the floss down and back up, which cleans almost nothing and irritates the gum.

I watch patients demonstrate their flossing all the time, and the up-and-down snap is by far the most common mistake. The good news is that the correct technique takes about a minute to learn and a couple of weeks to become automatic.

Why the Technique Matters

The point of flossing is not to pull food out from between teeth, although it does that. The point is to remove plaque from the two surfaces a toothbrush cannot reach: the sides of each tooth where it touches its neighbor, and the little pocket where the gum meets the tooth. Plaque in those spots is what causes cavities between teeth and gum inflammation, and it hardens into tartar within a day or two if left alone.

If the floss goes in and comes straight back out, it touches only the contact point. The sides of the teeth and the gum pocket are untouched. You could floss every day for a year that way and still have bleeding gums. If that sounds familiar, why do my gums bleed when I floss explains what the bleeding means and why it usually stops once flossing is done properly.

Step by Step With String Floss

Pull off about eighteen inches. That sounds like a lot, and it is, but you need fresh sections as you go. Wind most of it around one middle finger and a little around the other. Pinch a short span, about an inch, between your thumbs and index fingers. That short span is what gives you control.

Guide it between two teeth with a gentle side-to-side sawing motion. Do not force it straight down. When it pops through the contact, it should not slam into the gum.

Now the part everyone skips. Curve the floss around one tooth so it hugs the side like the letter C. Slide it gently down until you feel slight resistance under the gum, then move it up and down against that tooth two or three times. Then reverse the curve so it hugs the other tooth in the same gap, and repeat. That is one gap, two teeth.

Move to a clean section of floss and go to the next gap. Do not forget the back side of the last molar on each side. It has no neighbor, but it still has a side and a gum pocket.

Pressure

Gentle. You are wiping, not scrubbing. If you feel sharp pain or the floss cuts the gum, you are pushing too hard or snapping. Mild tenderness in the first week or two is normal if your gums are inflamed and will fade.

Brush First or Floss First?

There is some evidence that flossing before brushing lets the fluoride from toothpaste reach between the teeth better, and I lean that way. But the honest truth is that the order matters much less than doing both. Pick the order you will actually stick with.

Once a day is the goal. Nighttime is best, because plaque left overnight has hours of undisturbed time to do damage. If you only floss once, do it before bed.

Floss Picks vs String

Floss picks, the little plastic handles with a short strand of floss, are easier to use, especially for back teeth and for people with limited hand mobility. The drawback is that the same short piece of floss goes into every gap, so you carry plaque from one spot to the next, and the taut strand makes it harder to form a proper C shape.

My view: a floss pick used with the C-shape motion beats string floss that stays in the drawer. If picks are what get you flossing, use them, and rinse the strand between gaps when you can. If you can manage string, it does a slightly better job.

Water Flossers

A water flosser shoots a pulsing stream of water between the teeth and along the gumline. It is easy, feels good, and is very helpful for people with bridges, implants, or gum pockets that are hard to reach. It is also good at flushing out food debris.

What it does less well is physically scrape sticky plaque off a flat tooth surface. For most people I suggest a water flosser as an addition to string or picks, not a full replacement. If you genuinely will not use string, a water flosser used daily is far better than nothing. The American Dental Association has a short guide on interdental cleaners that covers the range of tools.

Tight Contacts and Other Problems

If floss shreds or gets stuck in one spot every time, tell me. That usually means a rough filling edge, a bit of tartar, or an early cavity between those teeth, and it is a useful clue. Waxed floss or a PTFE floss slides through tight contacts more easily than unwaxed.

If you have larger gaps between teeth, small interdental brushes may clean better than floss in those spots. If you have a bridge, you will need a floss threader or a floss with a stiff end to get under the false tooth. And if your gums have receded, a water flosser or interdental brush reaches the wider spaces well.

When to See a Dentist

If your gums keep bleeding after two or three weeks of proper daily flossing, if floss catches or shreds in the same place, or if you are not sure your technique is working, bring it up at your next routine exam. Our hygienists will happily watch you floss and correct it on the spot. It takes two minutes and it is one of the highest-value things we do. And if you are overdue for a cleaning, this post explains why that matters even for people who floss well.

Frequently Asked Questions

What is the correct way to floss?

Slide the floss gently between two teeth, curve it into a C shape around one tooth, and move it up and down along that tooth’s side and slightly under the gumline. Then curve it around the neighboring tooth and repeat. Use a clean section of floss for each gap.

Should you floss before or after brushing?

Either order works, and consistency matters far more than sequence. There is some evidence that flossing first helps toothpaste fluoride reach between the teeth, so that is a reasonable default. Flossing before bed is the most useful time of day.

Are floss picks as good as regular floss?

Floss picks are easier to use but harder to wrap into a proper C shape, and the same short strand goes into every gap. String floss does a slightly better job when used correctly. A floss pick used daily is still much better than string floss that stays in the drawer.

Can a water flosser replace flossing?

A water flosser is excellent at flushing debris and reaching around bridges, implants, and gum pockets, but it is less effective at scraping sticky plaque off tooth surfaces. For most people it works best as an addition to string floss or picks. If you will not use string, daily water flossing is far better than nothing.

Not Sure Your Flossing Is Working? Dr. Mirzaeian Can Help

A quick hands-on demonstration at your next cleaning can fix a technique problem that has been undermining your effort for years. Contact us to set up a consultation and we will make sure your home care is doing its job.

Lovik Mirzaeian, DDS has achieved extensive training in multidisciplinary dental treatments. His credentials include Dental Implants, Cosmetic Dentistry, Full Mouth Reconstruction, Endodontics, Oral Surgery, Orthodontics, and Sleep Sedation. Our office puts your comfort and smile first, and we are dedicated to giving you top-notch dental care. Get ready to show off your perfect smile!

Looking for a trusted family dentist in Clovis? Dr. Mirzaeian welcomes new patients of all ages.