The present invention relates to a rotary toothbrush as an improvement for the conventional toothbrush. Each reaction vessel has a receptacle portion having an emitting area from which light can emanate. The lamp includes a thermal handling system having a heat sink and a thermal core made of a thermally conductive material to dissipate the heat generated by the solid state light emitting sources to a point outside the lamp. In a direction perpendicular to a direction to connect the first and second semiconductor regions, the fourth semiconductor region has a width smaller than that of the semiconductor substrate sandwiched between the first semiconductor region and the second semiconductor region. The element is secured to the membrane by sealing after the device is applied to the neck and the element forced to urge the membrane against the neck.