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Abrasive effect of a rotating electrical toothbrush on dentin.

The Rota-dent brush has been compared to conventional manual toothbrushes as to the abrasive effect on the dentin. Thirty-two teeth were embedded in epoxyresin. The test blocks were ground and polished, thereafter brushed with Jordan Soft, Jordan Blå Kjerne, Wisdom Plaque Master (hard) and three different Rota-dent brushes, Standardpoint, Hollow-cup and Longpoint. The brushing experiment was made in a test chamber filled with distilled water. After the brushing, the profiles of the brushtracks on the blocks were measured. On all the blocks, small tracks appeared which were not measurable. Conventional toothbrushes and Rota-Dent brushes used without dentifrice gave minimal abrasion on the dentin.