Abstract: An improved apparatus for dispensing cleaning powder in an air stream to be directed onto the surface of teeth includes a fluid-tight chamber for containing a supply of cleaning powder and having an open space above the powder, with an elongated tube mounted in the chamber and having a bottom end adjacent the bottom of the chamber and an open top end above the powder supply in the chamber, and with openings in the tube permitting limited flow of powder into the tube by gravity. Air under pressure is directed into the bottom of the tube to entrain the powder and discharge it in an air-powder stream from the open top of the tube. An outlet in the sidewall of the chamber permits air and powder to flow out under pressure, and a movable deflection member deflects the stream of air and entrained powder from the open top of the tube above the powder supply and generally toward the outlet.