Interdental Brushes: How to Choose, Use Correctly, and Who Really Needs Them

What Are Interdental Brushes and Why Do You Need Them

Interdental brushes are small, specialized brushes designed to clean the spaces between teeth — areas that a regular toothbrush simply cannot reach. In short, interdental brushes are an essential tool for thorough daily oral hygiene. They remove plaque and food debris from the spots where cavities and gum inflammation most commonly begin.

Interestingly, even specialized single-tufted toothbrushes clean only about 60–70% of tooth surfaces, leaving interdental contact areas untouched. Interdental brushes handle plaque buildup in those areas effectively.

Used regularly, interdental brushes help to:

• Remove plaque, including between teeth
• Thoroughly clean out food remnants
• Effectively prevent tooth decay
• Monitor gum health and prevent gingivitis and periodontitis
• Improve breath freshness overall

GOOD TO KNOW: In professional terminology, these brushes are also referred to as “dental brushes” or “interdental brushes” (from the Latin inter — between, dens — tooth).

It is important to understand that interdental brushes are one part of a comprehensive approach to dental and gum health — which also includes proper brushing technique, regular toothbrush replacement, gentle gum care, and individually selected hygiene products.

Who Especially Needs Interdental Brushes

Interdental brushes are not just a tool for people with braces, as many tend to think. Although when orthodontic appliances are present, an interdental brush for braces is particularly essential — it cleans around brackets and wires far better than a regular toothbrush.

Interdental brushes are also highly beneficial for people who have:

• Any orthodontic appliances (braces, retainers, etc.)
• Crowded teeth or noticeable gaps between teeth
• Crowns, bridges, or dental implants

There are also symptoms that indicate insufficient interdental hygiene. When these are present, dentists typically recommend a consultation and the introduction of interdental brushes into the daily routine:

• Food frequently getting stuck between teeth
• Increased sensitivity of the gums or teeth
• Frequent gum irritation or bleeding

In these situations, interdental brushes move from being an optional addition to a necessary part of daily care.

How to Choose the Shape and Size of an Interdental Brush

Choosing the correct brush size is key to safe and effective use. Interdental brushes must match the size of the gaps between your teeth. A brush that is too small will fail to clean thoroughly, while one that is too large may injure the gums.

Available Brush Shapes

The main shape options are:

• Cylindrical — universal brushes suited to even, uniform gaps between teeth
• Conical — better suited when the width between teeth varies
• Angled — designed to improve access to the back molars

All of these shapes are commonly used with complex dental appliances such as braces, retainers, implants, and bridges.

How to Tell You Have the Right Size

Use the following criteria as a guide:

• The brush fits snugly into the gap, but without pain
• No excessive force is needed to clean
• No scratching or sharp discomfort during use
• The brush does not get stuck or bend immediately upon insertion
• The bristles make contact with the tooth surfaces rather than floating freely in the gap

RECOMMENDATION: If you are unsure about choosing the right size on your own, consult your dentist or orthodontist for personalized guidance.

How to Use an Interdental Brush Correctly

Knowing the proper technique is just as important as having the right brush. Incorrect use can injure the gums and reduce the effectiveness of the cleaning.

Step-by-Step Technique Without Gum Trauma

The process is straightforward:

1. Start with a clean interdental brush
2. Gently insert it into the interdental space
3. Make 2–3 smooth back-and-forth strokes
4. Rinse the brush with water
5. Move on to the next gap

KEY RULE: Never force the brush. Use gentle, controlled movements throughout.

Common Mistakes to Avoid

The most frequent errors include:

• Using a brush that is too large for the gap
• Trying to force the brush through with pressure
• Making sharp or aggressive movements
• Continuing to use a damaged or bent brush
• Ignoring persistent bleeding that does not resolve

REMEMBER: Even the highest-quality interdental brushes are only effective when used with a gentle, correct technique.

What Is Better: an Interdental Brush, Floss, or a Water Flosser?

The key point here is that these tools are not interchangeable — they complement one another, together forming the ideal approach to daily interdental cleaning.

• Interdental brush — the best option for visible gaps between teeth and for cleaning around orthodontic appliances
• Dental floss — better suited for very tight contacts between teeth where a brush cannot fit
• Water flosser (irrigator) — a supplementary tool for gum massage and flushing out food particles from interdental spaces

In most cases, combining two or more of these tools delivers significantly more thorough cleaning than using any single one alone.

Why Gums May Bleed and When to See a Dentist

Mild bleeding during the first few days of using an interdental brush is a normal reaction — and actually a sign that the gums were already inflamed and plaque had accumulated in those areas. The gums gradually adjust to the new cleaning routine, and this initial sensitivity typically subsides within a few days of consistent use.

That said, certain symptoms should not be ignored. See a dentist if:

• Bleeding does not stop after 5–7 days
• You experience pain or swelling of the gums
• An unpleasant odor from the mouth develops

In these cases, no brush — however small or gentle — will resolve the problem without professional treatment. A dentist can rule out inflammatory gum disease and help you select the right brush size for your specific situation.

Frequently Asked Questions

How often should I use interdental brushes? Once a day is sufficient — ideally in the evening, after brushing your teeth.

Are interdental brushes suitable for use with braces? Absolutely. They are one of the most effective supplementary hygiene tools available for people with orthodontic appliances.

How do I know if I have chosen the right size? The brush should slide into the interdental space without pain, sit snugly against the teeth, and not bend immediately on insertion. When in doubt, your dentist can help you determine the correct size at your next appointment.

Can I replace an interdental brush with dental floss? It is generally not recommended. Floss is designed for very tight contacts between teeth, while interdental brushes are better suited to wider gaps and areas around orthodontic appliances — they serve different purposes.

Why do my gums bleed after using an interdental brush? Bleeding is most often caused by gum inflammation or using a brush that is too large for the gap.

How often should I replace my toothbrush and my interdental brush? A regular toothbrush should be replaced every 3–4 months. Interdental brushes wear out faster — replace them as soon as they begin to bend, typically after 1–2 weeks of use.

Written by Vitalina Zubrii, Pediatric Dentist & Restorative Dentist