An electric toothbrush, motorized toothbrush, or battery-powered toothbrush is a toothbrush that makes rapid automatic bristle motions, either back-and-forth oscillation or rotation-oscillation, in order to clean teeth. Motions at sonic speeds or below are made by a motor. In the case of ultrasonic toothbrushes, ultrasonic motions are produced by a piezoelectric crystal. A modern electric toothbrush is usually powered by a rechargeable battery charged through inductive charging when the brush sits in the charging base between uses.
A typical electric toothbrush
A Motodent electric toothbrush. A patent for this toothbrush was filed in 1937.
Electric toothbrush
A toothbrush is an oral hygiene tool used to clean the teeth, gums, and tongue. It consists of a head of tightly clustered bristles, atop of which toothpaste can be applied, mounted on a handle which facilitates the cleaning of hard-to-reach areas of the mouth. They should be used in conjunction with something to clean between the teeth where the bristles of the toothbrush cannot reach - for example floss, tape or interdental brushes.
Three plastic toothbrushes
The horsehair toothbrush was said to have been used by Napoleon Bonaparte (1769–1821)
'Indexo' finger toothbrush, New York, United States, 1901–1919. It is made entirely of rubber, which has been shaped to fit over the index finger.
A photo from 1899 showing the use of a toothbrush.