Clinically proven: Removes plaque 10 times better than the brush heads of the best-selling private label in Germany (12-week average plaque removal, Nielsen Trade Panel L12M). The original brush heads from Oral-B are designed with X-shaped bristles that clean areas that regular bristles cannot reach. The green indicator bristles gradually turn yellow depending on individual usage, indicating the optimal time to replace the brush head - for 100% cleaning power.