Electric toothbrush and toothpaste. Toothpaste being added from a tube (right) to the head of an electric toothbrush. Electric toothbrushes have a motor that vibrates and turns the toothbrush head to help clean the teeth. Regular brushing of teeth helps to prevent tooth decay by removing scraps of food and bacterial plaque that can accumulate on the teeth. Toothpaste contains abrasive substances that help clean the teeth. Some toothpastes also contain fluoride, as this also helps to prevent tooth decay.