By supplying a dentist's unit with joint made supports in the shape of arms (5, 7, 13), as carriers of respectively a bracket table (9) and a lamp (16), built in actuators can be programmed for adjustment of the supports. Furthermore, signal transmitters in the shape of light transmitters (17) can be mounted to the underside of the bracket table (9) and the lamp (16) for visual display of desired data for the treatment, in form of the patient's condition or instrumental data for display (19) onto the patient (21).