A toothbrush includes a housing having a handle and a toothbrush head, a pump having a pump chamber and a pump impeller or pump gear arranged in the pump chamber, and a motor driving the impeller or pump gear. An input port and an output port are connected to the chamber, the impeller causing a flow of a working fluid through the output port when the impeller is driven by the motor and the working fluid is supplied through the input port. The pump chamber has a circumferential wall defining a transverse cross section, the output port being connected to the pump chamber through the circumferential wall.