Oral-B Pro-Expert Pro-Flex Toothbrush Medium features individual Pro-Flex sides as well as crisscross bristles which adapt to your mouth. These combine to confer the ultimate cleansing experience, removing up to 90% of plaque accumulated at the back. All in all, you're likely to achieve a satisfying outcome, as this remains as delicate as ever when touching your teeth/gums. According to tests, its daily use removes up to 34% more plaque along the gum line than toothbrushes with conventional bristles.