Interdental Cleaning Guide: Floss, Interdental Brushes and Water Flossers Compared

Brushing cleans only some of the surfaces of your teeth. The tight spaces between them, where decay and gum disease often begin, need a different tool. That job is called interdental cleaning, and it is the step in a daily routine most people skip. This guide compares the main options, string floss, interdental brushes, floss picks and water flossers, and explains who each one suits, how to use it, and how to buy genuine products. It is part of our wider daily oral hygiene guide.

Why cleaning between teeth matters

Plaque is a sticky film of bacteria that builds up on every tooth surface. A toothbrush reaches the front, back and chewing surfaces, but its bristles cannot get into the narrow spaces between neighbouring teeth. Left alone, plaque there can cause cavities between teeth and inflame the gums, which is the first stage of gum disease. Health organisations such as the NHS and the American Dental Association recommend cleaning between your teeth once a day, in addition to brushing twice a day with a fluoride toothpaste.

Most people do not do it. The usual reasons are that string floss feels awkward, takes time, or makes gums bleed. The good news is that you do not have to use floss. Several tools do the same job, and the best one is the one you will actually use every day.

The main options at a glance

String floss

Floss is a thin thread, waxed or unwaxed, that you slide between teeth and curve around each tooth in a C shape. It is the oldest and cheapest option, and it works well for teeth that touch closely. Waxed floss slides more easily, unwaxed floss is thinner, and flat dental tape suits wider spaces. Technique matters more than the type. Never snap floss down onto the gum, and use a fresh section for each gap. Our step-by-step article on how to floss correctly covers the movements in detail.

Choose floss if your teeth are tightly spaced and you are comfortable with the technique.

Interdental brushes

These small brushes have a thin wire core and tiny bristles, and they come in colour-coded sizes. You slide the brush gently into the space and move it in and out. Many people find them quicker and easier than floss, and they can be more effective where the gap is large enough, because they clean the whole width of the space instead of a thin line. The key is a snug fit: too small and they clean poorly, too large and they hurt the gums. A dentist or hygienist can measure your gaps, and you may need different sizes for different areas. Replace a brush when the bristles bend or fray.

Choose interdental brushes if you have visible gaps, gum recession, bridges, or braces.

Floss picks and soft picks

A floss pick is a small plastic handle with a short length of floss stretched across it. It is easy to hold and reaches back teeth without putting fingers in your mouth. A soft pick, or interdental stick, has rubbery bristles on a plastic or wooden core, and suits wider gaps. Both are convenient and good for travel. Their drawbacks are that you have less control over the angle, and a pick does not wrap around a tooth the way floss does. If you use a floss pick, use a fresh section or a new pick for each gap, so you do not move bacteria around.

Choose picks if convenience is what keeps you cleaning between your teeth, since a pick used daily beats floss left in a drawer.

Water flossers

A water flosser sends a pulsing jet of water between your teeth and along the gumline. It is easy for people with braces, implants, bridges or limited hand movement, and gentle for many users. There are countertop models with large reservoirs and cordless models that are portable. Water flossers are widely accepted as a valid way to clean between teeth, and some dentists recommend combining them with floss or interdental brushes. They cost more than other options and need regular cleaning. Our water flosser guide explains the types, how to use one, and how to check whether a model has the ADA Seal.

Choose a water flosser if string floss is hard for you, or you have braces or dental work that is awkward to clean.

How to choose

1. Look at your gaps. Tight contacts suit floss, and visible gaps suit interdental brushes.
2. Think about your hands. If you have arthritis, a tremor or limited grip, picks, interdental brushes with handles or a water flosser are usually easier.
3. Consider your dental work. Braces, bridges and implants often need a brush or water flosser.
4. Be honest about habits. Pick the option that you will use daily.
5. Ask your dentist or hygienist. They can show you the right tool and size for your mouth.

Braces, implants, bridges and gaps

• Braces. Floss threaders, orthodontic floss, interdental brushes and water flossers help you clean around brackets and wires.
• Implants and bridges. These need careful cleaning under and around them. Interdental brushes sized for the space and water flossers are common choices, and your dentist can advise on the right method.
• Receding gums and larger gaps. Interdental brushes usually clean these better than floss.
• Children. Once teeth touch, an adult will usually need to help with floss or a pick.

Fitting it into your routine

Do it once a day, at the time you are most likely to remember. Many people clean between their teeth at night, then brush. Others prefer to do it before brushing so the fluoride toothpaste reaches the spaces. The order is less important than doing it regularly. Keep your tool next to your toothbrush where you will see it. If your gums bleed when you start, keep going gently. Bleeding from inflamed gums often settles within one to two weeks of daily cleaning. If it does not, or your gums are painful, swollen or receding, see a dentist.

Common mistakes

• Snapping floss down between teeth, which can cut the gum.
• Using the wrong brush size, which either cleans poorly or hurts.
• Skipping the back teeth, where plaque builds up most.
• Reusing a dirty section of floss from gap to gap.
• Relying on mouthwash alone. Rinsing does not remove plaque from between teeth.
• Stopping when gums bleed, when they most need cleaning.

A simple first-week plan

If you have never made interdental cleaning a habit, a gradual start helps. Pick one tool and one time of day, and keep it the same for the first week.

1. Days 1 to 3. Clean between your back teeth on one side only. Be gentle and go slowly. Some tenderness and light bleeding are common at the start.
2. Days 4 to 7. Add the other side, then the front teeth. Check the sizes of your interdental brushes and swap any that feel too tight or too loose.
3. After one week. Aim to clean every gap once a day. Most people find the whole routine takes about two minutes.
4. After two weeks. Gums that were bleeding should look and feel firmer. If they do not, mention it to your dentist.

Interdental cleaning for children and older adults

Children need help with interdental cleaning until they have the dexterity to manage it, and a floss pick is often the simplest way for an adult to help. Older adults may have more gaps, receding gums, bridges or dentures, which make interdental brushes and water flossers especially useful. For anyone with limited hand strength, handles, holders and cordless devices reduce strain. If you care for someone else, ask a dental professional to show you the safest technique for their mouth.

What to remember

Good interdental cleaning does not depend on one special product. It depends on a tool that fits your gaps, a gentle technique and a daily habit. Choose the option that suits your teeth and hands, check the exact product on the ADA list if you want extra reassurance, and keep brushing twice a day with fluoride toothpaste. Regular interdental cleaning is one of the simplest ways to protect your gums, and a few minutes a day is enough.

Buying genuine products

Look for the brand’s own website first, then established pharmacies and retailers. Check the exact product against the ADA’s list, as explained in our ADA Seal guide. The Seal covers some floss, interdental cleaners and water flossers, though not every product. Be wary of very cheap branded items sold by unknown sellers, particularly replacement tips for water flossers. We do not list prices because they differ between countries and change often. You can compare tools and other categories on our dental products page.

Quick answers

Which is best, floss or interdental brushes?

Neither is best for everyone. Floss suits tight contacts, and brushes suit larger gaps. The best option is the one that fits your teeth and that you will use daily.

Can a water flosser replace floss?

It is a valid way to clean between teeth, especially with braces or dental work. Some dentists suggest combining methods, so ask your own dentist.

How often should I clean between my teeth?

Once a day is the standard recommendation, in addition to brushing twice a day.

Keep learning

• How to floss correctly
• Water flossers explained
• Checking the ADA Seal
• Daily oral hygiene guide

Sources

• NHS, How to keep your teeth clean
• American Dental Association, Daily routine
• US National Institute of Dental and Craniofacial Research, Oral hygiene
• Waterpik, Buying guide (manufacturer information)

This guide is general information and does not replace advice from your dentist. See our Disclaimer and Editorial Policy.