Most electric toothbrushes are no better for your teeth and gums than the traditional type powered only by elbow grease, researchers have found.

Scientists from the Universities of Birmingham, Edinburgh, Manchester and Sheffield found that only one type of electric toothbrush produced better results despite being many times more expensive.

People are certainly fooling themselves, with the majority of brushes at least, if they think they are more effective Professor Bill Shaw

They found that brushes with a rotation-oscillation action are more effective at reducing potentially harmful plaque from the surface of the teeth.

However, the long-term effect on dental health may still only be borderline.

There was some good news for fans of electric toothbrushes - they are no worse than the manual variety, and there is little evidence they will cause more injuries to the gum.

Delusions

Professor Bill Shaw, of the University Dental Hospital in Manchester, who led the study, said: "People are certainly fooling themselves, with the majority of brushes at least, if they think they are more effective."

The research was coordinated by the Cochrane Oral Health Group, an independent group of experts who examined results from 29 clinical trials of electric toothbrushes involving 2,500 people.

The brushes were split into five types, depending on the action of their heads:

• side-to-side
• circular
• ultra-sonic vibration
• rotation-oscillation in which a circular head spins back and forth in quick bursts
• counter oscillation, in which tufts of bristles rotate in different directions simultaneously

Only the rotation-oscillation brushes out-performed manual brushing.

They removed around 7% more plaque and led to 17% less gum disease than manual brushes.

Fluoride toothpaste

The researchers found that the best way to avoid tooth and gum disease was to use fluoride toothpaste. This cut the number of cavities in children aged five to 16 by 24% over three years.

Dr Gordon Watkins, of the British Dental Association, said: "Which toothbrush you use is a matter of choice. Some feel more comfortable with a manual toothbrush, others with an electric one.

"The most important thing is that, whatever brush you use, you use it properly, getting into the nooks and crannies and just under the gum line."

Chris Potts, of Boots the Chemist, said: "Electric toothbrushes tend to help people who are not as good at cleaning teeth and as a result have had oral hygiene problems."