Since the beginning of the Dr.Collins brand, our Perio Toothbrush has been our bestselling and highest reviewed product. With its tapered polyester bristles, the Perio Toothbrush has been providing a supersoft brushing experience that is unrivaled to this day. Now, Dr.Collins is proud to introduce the newest evolution of the bestselling Perio Toothbrush: Dr.Collins Perio Extreme Toothbrush! Compared to the original Perio Toothbrush, the Perio Extreme has 25% thinner bristles as well as a 25% increase in the total amount of bristles. This higher concentration of ultra-thin bristles means the Perio Extreme is even softer and gentler than the original Perio!