Electric Toothbrush - Ultrasonic Toothbrush

Ultrasonic Toothbrush

The newest development in this field are the ultrasonic toothbrushes, or simply sonic toothbrushes using ultrasonic waves to clear the teeth. In order for a toothbrush to be considered "ultrasonic", it has to emit a wave at a minium frequency of 20,000 hertz or 2,400,000 movements per minute. Typically ultrasonic toothbrushes approved by the FDA operate at a frequency of 1.6MHz, which translates to 192,000,000 movements per minute. Most ultrasonic toothbrushes have an additional sonic vibration ranging from 9,000 to 40,000 movements per minute. Any toothbrush operating at a frequency or vibration less than 2,400,000 movements per minute (20,000 hertz) is a "sonic" toothbrush. It is called sonic because its operating frequency, for example of 31,000 movements per minute, falls into the human hearing range of between roughly 20 hertz to about 20,000 hertz.