Disposable dental instrument

Abstract

A disposable dental instrument of the compressed air drive type is disclosed for use in performing dental procedures on a workpiece. The disposable dental instrument is constructed from two mating shells and a core. Each shell incorporates a mating surface and the shells are joined using various bonding methods to ensure a waterproof, high quality dental instrument. An elongated body has conduits penetrating a base at one end of the body. The conduits allow entry of a light beam, a pressurized water stream, and a compressed air stream into the body. The base includes attachment threads for securing the body to a source of the light beam, pressurized water stream, and compressed air stream. Pluralities of passageways are in communication with the conduits for conducting the light beam, the water stream, and the air stream through the body. A head at the opposite end of the body rotatably mounts a turbine shaft on bearing surfaces which inhibit vibration and noise. The turbine shaft includes a turbine impeller and a clamping hole for removable attachment of a dental bur to the shaft. The air stream drives the impeller at a high speed for rotating the bur about a rotational axis. An opening in the body adjacent to the head allows release of the light beam, the pressurized water stream, and a portion of the compressed air stream in a direction toward the distal end of the bur so that the bur, the light beam, the water stream, and the air stream may all converge on the workpiece.