Fluid spray system for dental handpiece

Abstract

A dental handpiece having an improved water/air spray system including a pair of substantially parallel tubes, one for water and the other for chip air, extending through the handle of the handpiece and terminating in a nozzle chamber of oval cross section. The tubes are generally cylindrical but are partially deformed at their distal ends, such deformation constituting a flattening of adjacent wall portions of the respective tubes. Such adjacent wall portions are disposed in contiguous relation and are cut away for a limited distance at the discharge end of the tube assembly to define the unitary nozzle chamber. The chamber has an oval discharge orifice for directing an elliptical spray pattern towards the tip of the dental bur. At the opposite end of the handpiece, the handle is equipped with a plug terminating in an external end face. Tubular extensions project from that end face for conveying air to the drive air and chip air passages. An open channel formed in the end face of the plug communicates with annular recesses disposed about such extensions, and each extension is provided with a lateral aperture communicating with the surrounding recess. The open side of the channel and the ends of the recesses are sealed by a sealing member when the handpiece is in operation.