589979 A dental fluid delivery system for use with a dental drill is disclosed. The delivery system comprises a coolant water supply unit (51), a drive air line (52), a water line (53) and a coolant mist air controller (80). The coolant water supply unit (51) includes a controller (10) and a water container (11), the water controller (10) having a drive air inlet (43), a water inlet communicatively connected to the water container, a drive air outlet (46) and a water outlet (31). A first bore within the controller (10) permits passage of drive air from the air inlet (43) to the air outlet (46) and is controller with a knob (55). A second bore extending from the first bore permits drive air into the water container (11). A third bore extending from the water container (11) permits passage of liquid from the container (11) to the water outlet (31), and fourth and fifth bores separated by a flexible membrane selectively controls communication between the fourth bore and an exhaust vent. The drive air line (52) is connected to the drive air outlet (46) of the water supply unit (51) and the water line (53) is connected to the water outlet (31) of the water supply unit (51). The coolant mist air controller (80) connects to a dental drill (50), the mist air controller (80) having a drive air inlet (99), a drive air outlet, a water inlet (84), a water outlet, and a mist air outlet.:
