Abstract: An apparatus (20, 30) operative from a first liquid pressure only and configured to generate and selectively direct a stream of first liquid or a third liquid is disclosed. Since no electrical power is used, the apparatus can be safely operated in any moist environments (e.g. a shower). In preferred embodiments, the apparatus is configured to operate in series with a showerhead (22) and a sink tap (32) for dental irrigation. Either water or dental solution which is comprised of water mixed with dental concentrate, can be independently selected. A mixer valve (48) controls the concentration of the irrigating solution. A handheld syringe (40) contains all other controls necessary for operation.

Abstract: An oral irrigating liquid dispenser (20) is disclosed which operates from a liquid pressure source (22) to dispense two liquids (54, 72) from an orifice (26). A valve member (24) moves to different positions to couple the source respectively to a piston face (64A), a conduit (60) and an outlet port (71). Flow control valves (80, 89) are provided to control flow from the orifice. Since no electrical power is involved the dispenser may safely be used in the presence of liquids and electrical grounds.