An electric toothbrush has an axially elongated body having a handle defining a hollow interior region for holding a motor disposed therein, a head comprising a static bristle holder plate having tufts of bristles disposed thereon and an oscillatory head bristle holder with other tufts of bristles disposed thereon. One end of the drive shaft is connected to the motor and an opposite end to a cam for directly driving the cam which has at least one lobe a portion of which cam is received in an oscillatory cavity for imparting a pushing force on the walls of the oscillatory cavity in response to rotation of the drive shaft for moving the oscillatory head bristle holder with a back and forth oscillatory motion. By eliminating the need for precision gearing, this direct drive arrangement simplifies and makes more efficient the translation of rotary motion into oscillatory motion.