A sensor-responsive toothbrush that can adjust its output or operation depending upon information received by one or more sensors incorporated in the toothbrush or as selected by a user. The information typically relates to certain conditions or the presence of particular substances or agents within or outside of the oral cavity. The sensor-responsive toothbrush also includes one or more responsive output components that provide a responsive output in response to the sensed information. A method of providing an oral care benefit, comprising steps of: activating a toothbrush comprising a sensor detecting a sensor input with the sensor and initiating a responsive output from the toothbrush in response to the sensor input.