ULTRASONIC TOOTHBRUSHES, WHICH USE ULTRASONIC WAVES TO CLEAN THE TEETH

The newest developments in this field are ultrasonic toothbrushes, which use ultrasonic waves to clean the teeth. In order for a toothbrush to be considered “ultrasonic” it has to emit a wave at a minimum frequency of 20,000 hertz or 2,400,000 movements per minute.

The newest developments in this field are ultrasonic toothbrushes, which use ultrasonic waves to clean the teeth. In order for a toothbrush to be considered “ultrasonic” it has to emit a wave at a minimum frequency of 20,000 hertz or 2,400,000 movements per minute. Typically, ultrasonic toothbrushes approved by the U.S. Food and Drug Administration (FDA) operate at a frequency of 1.6 MHz, 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 31,000 movements per minute, is within the human hearing range of between roughly 20 hertz to about 20,000 hertz. The first ultrasonic toothbrush, first called the Ultima and later the Ultrasonex, was patented in the USA in 1992, the same year the FDA gave it approval for daily home use. Initially, the Ultima worked only on ultrasound, but a few years later, a motor was added to give the Ultrasonex brush additional sonic vibration. Today, most ultrasonic toothbrushes work simultaneously in the ultrasonic mode together with sonic.