Technique is obviously incredibly important.
A lazy person with an electric toothbrush would be as good as a very diligent person with a manual one.
But if you take the same person and give them an electric toothbrush, chances are they’ll do a bit better than when they just had a manual one. As long as they don’t become lazier
Short answer; yes, they are [as per this study](https://www.dentalhealth.org/news/electric-toothbrushes-win-the-head-to-head-against-manual-in-record-breaking-new-study).
That said, a poor electric-toothbrush user will be worse off than a great manual toothbrush user. But for a specific individual, putting in the same effort, they will get a better clean with an electric toothbrush than a manual one.
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