A toothbrush, comprising a battery, a source (117, 190) of visible therapeutic light with a wavelength in the range of 400nm to 500nm, electronics (110, 111) coupled to the battery and to the source of visible therapeutic light to supply electricity from the battery to the source of visible therapeutic light at current and voltage that causes the source of visible therapeutic light to emit light, the toothbrush including a handle and a distal end, the distal end including bristles on the distal end; wherein the source of visible therapeutic light is located at the distal end, or wherein the source of visible therapeutic light is installed in the handle, an aperture for emitting the light is located at the distal end and a light pipe installed at the distal end guides the light from the source of visible therapeutic light to the aperture, the electronics including a control circuit and a sensor or combination of sensors (210, 240, 248, 256, 280, 306, 314, 334) configured to determine whenever the distal end is outside the environment of the mouth and to permit activation of the source (117, 190) of visible therapeutic light only when the sensor or combination of sensors detect that the distal end of the device has been placed in the mouth, and wherein the control circuit is configured to activate the source (117, 190) of visible therapeutic light using a 0.5 to 5 second long ramp-up sequence that gradually increases the radiant power of the source of visible therapeutic light to allow ample time for the user to respond or trigger the eyes natural aversion reflex, such as blinking, if the light is too bright for the eyes, the source (117, 190) of visible therapeutic light thereby being an alarm that warns the user of the power status of the source of visible therapeutic light before the source of visible therapeutic light reaches full power. a battery, a source (117, 190) of visible therapeutic light with a wavelength in the range of 400nm to 500nm, electronics (110, 111) coupled to the battery and to the source of visible therapeutic light to supply electricity from the battery to the source of visible therapeutic light at current and voltage that causes the source of visible therapeutic light to emit light, the toothbrush including a handle and a distal end, the distal end including bristles on the distal end; wherein the source of visible therapeutic light is located at the distal end, or wherein the source of visible therapeutic light is installed in the handle, an aperture for emitting the light is located at the distal end and a light pipe installed at the distal end guides the light from the source of visible therapeutic light to the aperture, the electronics including a control circuit and a sensor or combination of sensors (210, 240, 248, 256, 280, 306, 314, 334) configured to determine whenever the distal end is outside the environment of the mouth and to permit activation of the source (117, 190) of visible therapeutic light only when the sensor or combination of sensors detect that the distal end of the device has been placed in the mouth, and wherein the control circuit is configured to activate the source (117, 190) of visible therapeutic light using a 0.5 to 5 second long ramp-up sequence that gradually increases the radiant power of the source of visible therapeutic light to allow ample time for the user to respond or trigger the eyes natural aversion reflex, such as blinking, if the light is too bright for the eyes, the source (117, 190) of visible therapeutic light thereby being an alarm that warns the user of the power status of the source of visible therapeutic light before the source of visible therapeutic light reaches full power.