An interdental brush is reusable, but only up to a point. A good rinse under the tap after each use and somewhere airy to dry is all the cleaning it needs, and the bigger mistake most people make is keeping it after the bristles have flattened or the wire has started to bend. A tired brush slides through the gap without cleaning much, and a kinked wire can scratch the gum.
Rinsing takes ten seconds
When you finish cleaning between your teeth, hold the brush under running lukewarm water and turn it slowly so the water flushes out the plaque and food caught in the bristles. If something is stuck, run it gently between your fingertips. Try not to rub the brush against the sink, which can bend the wire. Very hot water can soften or distort some brushes, so lukewarm is enough.
Then flick off the excess water. The aim is a brush that is clean and as dry as you can get it before you put it down. If you are still learning the technique itself, our guide to using an interdental brush covers sizing and angles.
Let it dry in the open air
Bacteria grow more readily on a brush that stays damp in a closed space, so store it upright in a clean holder or cup where air can reach it, as you would a toothbrush. Keep it away from the toilet and from touching other people's brushes. Many interdental brushes come with a cap, which is handy for a handbag or travel kit, but put it on only once the brush has dried.
The same idea applies to other things you put in your mouth every day. Our guide to cleaning a retainer or night guard explains how to look after appliances.
Disinfecting is optional
For a brush that only you use, rinsing and drying is enough for everyday hygiene. Bleach, boiling water and strong cleaning products are unnecessary and can damage the bristles or loosen the wire. If you like, you can dip it in an antibacterial mouthwash now and then and rinse it with water afterwards, but this is a preference rather than a requirement.
Signs it is time for a new one
How long a brush lasts depends on how often you use it, how many gaps you clean and how tight they are, so check it each time you pick it up and follow the replacement advice on the packet. Replace it when:
- the bristles look flattened, splayed or sparse
- the wire is bent, kinked or wobbly where it meets the handle
- bristles are coming out
- you have been unwell and would rather start fresh
Never share an interdental brush, even within a family. Brushes are inexpensive, and a new one cleans far better than a worn one.
Bleeding while you get started
Some bleeding is common in the first days of cleaning between the teeth, because the gums there are often inflamed. It usually settles as the gums get healthier. If the bleeding has not settled after 3 to 4 days of regular, gentle cleaning, or if a gap suddenly feels different, have your gums checked by a dentist or oral health therapist (OHT). Our guide to bleeding gums explains the common causes.
Common questions
Is an interdental brush single use?
No. The same brush can be reused for a while if you rinse and dry it after each use, until the bristles or wire show wear.
Should I use a different brush for different gaps?
Often, yes. Gaps vary in size, and many people need two or more sizes. Your dentist or OHT can show you which size suits each area.
Would a water flosser be easier?
Some people find one easier, especially around bridges or braces. Our comparison of a water flosser versus floss and interdental brushes looks at the options.
If you are not sure which sizes to buy, or think you might be missing some gaps, bring your brushes to your next check-up and our team can check your technique. You can book through our general dentistry page or see our current deals page.
