Abstract: In a dental apparatus, in which each of a number of instruments is controlled by a control circuit common to the instruments, which are connected with a common operator unit having a control member which is movable in planar directions out of a home position, auxiliary functions not related to the instrument operation may be carried out by means of the common operator unit by switching the apparatus to a second mode of operation, when all the instruments assume respective resting positions in an instrument carrier. Moreover, also auxiliary functions directly related to the instrument operation may be carried out by the common operator unit in a first mode of operation by actuating the control member thereof with a movement different from the instrument energizing movement. The movement for energizing such an auxiliary function may have another direction and/or a shorter duration than the instrument energizing movement.