The invention relates to a device for the controlled supply of compressed air to at least one pneumatically operated dental instrument (5, 5′, 5″, 5′″) from a supply and control unit (2), in which a dental instrument (5, 5′, 5″, 5′″) is connected by a supply hose (4, 4′, 4″, 4′″) for supplying compressed air with a valve mechanism (6) provided in the supply and control unit (2), the valve mechanism (6) having a plurality of pneumatic sliding valve units (9, 9′, 9″, 9′″). The pneumatic sliding valve units (9, 9′, 9″, 9′″) of the valve mechanism (6) are accommodated in at least one valve body (10) and the valve body (10) has a plurality of control connections (12, 12′, 12″, 12′″), whereby each pneumatic sliding valve unit (9, 9′, 9″, 9′″) corresponds to a control input (12, 12′, 12″, 12′″) and pressurization of a control input (12, 12′, 12″, 12′″) with switching compressed air opens the corresponding sliding valve unit (9″) and locks the additional, closed sliding valve units (9, 9′, 9′″).
