Abstract: Apparatus for use in operating a dental drill is disclosed in which the air, water and light for the hand-held drill member are each delivered from an associated supply source, all of which are adapted to be located at a position remote from the working end of the drill and are coupled to the drill through a conduit cable, and in which control means for the selective energization of the light supply source is located within easy reach of the operator to permit turn-on and/or turn-off of the light supply source through simple fingertip control provided within a remote control unit which is totally electrically isolated from the high voltage present in the light supply source to protect both the operator and the patient from shock or injury. The light supply source may be automatically energized merely by lifting the instrument containing the dental fiber optics.The light unit may be independent of the dental drill to permit a wide variety of uses independently of its use with the dental drill.