A toothbrush barely reaches the sides of teeth. An interdental brush does: a short bristle cylinder on a thin wire. It is usually a better fit when the gaps are wide enough, or if you have bridges, crowns, or braces.
How to pick a size
The brush should go in with light resistance, without pain and without shoving the gum aside. Too thin and it barely cleans. Too thick and it cuts. A mixed-size pack beats one “universal” brush, because front and back gaps are not the same.
Brand colour codes help you remember your size. They are not a medical scale. If you are unsure, ask for a fitting at a hygiene visit. The hygienist sees the real spaces, not the picture on the box.
How to use it
- Rinse the brush with water.
- Insert it parallel to the gum, not with a vertical sawing motion.
- Make a few short in-and-out passes.
- Move to the next space. Back teeth often need a bent handle.
Replace the brush when the bristles splay or the wire bends. Do not keep the same wet brush for weeks. It loses shape fast.
Common mistakes
- forcing it through a gap that will not accept it;
- using it instead of fluoride toothpaste;
- cleaning only the front teeth;
- storing a dirty brush in a closed wet cup.
Floss is better in very tight contacts. A water flosser helps as an extra step. It does not replace mechanical cleaning of the tooth sides. If the gum swells or you see pus after using a brush, stop and book a dentist. That is not a sizing tweak.
Clean between teeth once a day, ideally in the evening before fluoride toothpaste, so the fluoride sits on cleaner enamel.
Educational material. Sources: ADA/MouthHealthy, NHS, Cochrane on interdental cleaning. AIoraly does not diagnose or fit brush sizes remotely.