The power toothbrush includes a handle (12) and a brushhead (18) having a conductive electrode sensing element (25) therein. The toothbrush includes a driver assembly (14) for the brushhead and a sensor system (28) for measuring the capacitance between the sensing element on/in the brushhead and an electronics ground (27) in the handle of the toothbrush. A microprocessor/controller (26) is programmed to determine whether the measured capacitance is above a threshold value which indicates that the toothbrush is near or within the mouth of the user. The microprocessor actuates the driver assembly for operation of the toothbrush when the capacitance value is above the threshold value.
