They did also make this claim:
> Dyson’s brushing action prevents stalling, keeping bristles in constant motion to remove more plaque vs. market leading premium electric toothbrushes in a laboratory test in brush-only variable mode in the hard to reach areas. [0]
Maybe one was an actual, independent though Dyson funded study and the other just their internal comparison to competitors? When I last upgraded my electric toothbrush, I read some studies looking into performance of Oral-B and co. and, to a layman, it seemed like most proper independent studies used manual as the base line.