Abstract: An endodontic irrigating instrument comprises a handpiece having an internal liquid passage therethrough extending from a liquid inlet formed in the proximal end of the handpiece to a liquid ejection nozzle provided at the distal end. The handpiece incorporates a suction or vacuum pump of the airjet or ejector type which comprises an air nozzle connected by a passage with an air inlet formed also in the proximal end of the handpiece. The vacuum chamber of the suction pump is connected by a separate internal passage in the handpiece with an aspiration needle provided adjacent to the liquid ejection nozzle. The proximal end of the handpiece is designed to be fitted with a coupling joint attached to a multiple-channel flexible hose which is conventionally used to supply compressed air and pressurized water from a dental unit to conventional air-driven dental turbine tools. Thus, the endodontic irrigating instrument can be used interchangeably with existing turbine tools.