01/06/2026
If floss has an unpleasant smell after cleaning between certain teeth, it’s usually a sign that food debris, plaque, or bacteria have been trapped in that area.
The spaces between teeth can be difficult to clean with brushing alone, which is why flossing helps remove build-up that may otherwise remain unnoticed. When bacteria break down trapped food particles, it can create an odour.
This can sometimes happen more often in areas where:
• food tends to get stuck
• gums are inflamed
• plaque has built up
• or cleaning is more difficult due to tight spacing or dental work
Consistent flossing and good oral hygiene can help reduce this over time. If the smell persists regularly in the same area, it may be worth having it checked professionally.