Your toothbrush is worn-out!

What people said

error503 · 2023-05 · Recommendation

Probably depends on which body you are using. In mine it both flashes a tiny LED and does an extra little buzz-buzz buzz-buzz signal with the ultrasonics when you turn it on (or off, can't recall which) when the head has 'expired'. Continues to work fine, though. You might be interested in this YouTube video from Applied Science with electron micrographs of 'new' and 'worn' toothbrush bristles - there is a very marked invisible change that happens: [VIDEO]

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mrob · 2025-04 · Reference

Something else you could send: >Does dentifrice use help to remove plaque? A systematic review [LINK] "The cumulative evidence for this systematic review demonstrates that there is moderate certainty that toothbrushing with a dentifrice does not provide an added effect for the mechanical removal of dental plaque." I also don't use toothpaste. However, I do replace my toothbrush regularly (every 3 months, which I believe most dentists recommend). Toothbrushes have microscopic texturing to help them clean, which wears out with use. Here's a video showing it under an electron microscope: [VIDEO] A fresh toothbrush cleans noticeably better than a worn one. I think this is much more important than buying fancy expensive toothbrushes. Even the cheapest toothbrushes clean well when they're fresh, and the expensive ones wear out just the same.

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plausibility · 2024-11 · Reference

The usual problem with toothbrush bristles is they become microscopically worn down, so they don't scrape off plaque as effectively. Even if you can't see the problem, it might not be working as well as a fresh head will. You can find electron microscope scans of fresh toothbrushes and worn ones in this[0] Applied Science YouTube video. [0]: [VIDEO]

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