Abstract: An angle drive dental hand piece or prophy with a drive train including an essentially cylindrical spindle frictionally engaged by the turns of a spiral spring. The driving end of the spring which in turn rotates a tool holder carrying a dental tool such as a rubber scrubber. The drive spring is bent at an angle such as a right angle while being rotated and is of a diameter in relation to the housing bore through which it passes so that there is no engagement or consequent friction from any contact of the spring with the bore housing. Overload on the tool causes slippage between the spring and the spindle on which it is wound so that damage to the drive train components from overload is avoided.

Abstract: An automatic slide sleeving system in which a sleeve containing a plurality of pockets is moved past a rotatable member to which a vacuum is applied thereby drawing the sleeve along with the rotatable member to a position under a movable head where a second vacuum is applied pulling the pocket into an open condition and thereafter through an actuator mechanism, the slides which have been previously moved into position from a slide hopper by a shuttle are moved in to the open pockets by a tongue pusher after which the vacuums are removed and the rotatable member rotated thereby enabling the filled pockets on the sleeve to be collected.