A three-axis acceleration sensor is mounted to a body of an electric toothbrush. A CPU detects the three-dimensional attitude of the body based on an output from the acceleration sensor and, based on the attitude of the toothbrush, estimates which portion is being brushed. Then, the CPU performs control for switching between operation modes (such as the rotational direction of a motor and the frequency of vibration of the brush) according to the estimated portion being brushed.
