An adjustable bristle toothbrush apparatus which provides pneumatic bristle exposed length pressure adjustment. The mechanisms include providing an indication with a response to an operation of an interface that an alternative interface is available. An output value by control unit set in the dead-zone range is compared with a detected value to detect a failure of the control valve. Finally, the pigment coating is solidified, affixing the reoriented particles or flakes in a non-parallel position to the surface of the pigment coating to produce an image such as a three dimensional-like image on the surface of the coating.