Braun Oral B iO Ultimate Clean Replacement Brush Heads Black combines powerful, but gentle micro-vibrations with Oral-B's unique dentist-inspired round brush head design for a professional clean feeling every day. Ultimate clean refills help remove plaque, leaving teeth feeling clean and bright. Tufted bristles help clean hard-to-reach areas of the mouth. Dentists recommend changing your brush head every 3 months for best results.