Ultimate Clean combines Oral-Bs perfect angle with innovative new bristles for the best Oral-B clean ever To remove up to 100% of plaque from day one. On Oral-Bs unique round brush head, the bristles are meticulously arranged to better surround each tooth for the best possible cleaning. Dentists recommend replacing the brush head every 3 months for better cleaning. From the #1 dentist recommended brand worldwide. Number of toothbrush heads included in this pack: 2 Designed exclusively for your Oral-B iO. Guaranteed compatibility.