to the remaining instruments 1 conventionally on off means 7 are installed between the first and second branches 9 and 11 as in fig1 such means 7 are pedal controlled for the most part and operated directly by the user of the apparatus generally in conjunction with similar means 7a controlling the air circuit 16 with the exception of the water line 6a to the chip blower 10 the lines 6b branching to each of the various instruments 1 are controlled by relative on off means 5b which open at the moment when the instrument is taken up for use more exactly such means take the form of solenoid valves 5b located in the instrument holder t of the apparatus which excite only when the handpieces are removed from the holder and therefore remain closed as long as the relative instrument is not in use in the case of the chip blower 10 on the other hand on off means 5a are embodied typically as mechanically operated valves located downstream of the handpiece and manipulated by the user thus with the exception of the chip blower 10 each instrument 1 comprises two different sets of on off means 5b and 7 controlling the relative fluid circuits of which the means 5b located farthest downstream along the flow direction are activated automatically on taking up the handpiece and the means 7 upstream activated manually or in effect by depressing a pedal apparatus according to the present invention is provided with a reservoir 2 containing a supply of physiological medical healing or other solution dispensed by way of a relative supply line 3 into the main water circuit 8 the solution pipeline 3 and water supply.