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 said 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.

Abstract: A mechanism is disclosed for controlling capacity in a communication system, based on zones in which subscribers are located. When a subscriber seeks to establish a communication session among multiple subscribers, a determination is made as to whether more than a threshold number of the subscribers are located in a common zone. If so, the excess subscribers in that zone are excluded from participating in the session.

Abstract: A mechanism is disclosed for controlling capacity in a communication system, based on zones in which subscribers are located. When a subscriber seeks to establish a communication session among multiple subscribers, a determination is made as to whether more than a threshold number of the subscribers are located in a common zone. If so, the excess subscribers in that zone are excluded from participating in the session.