A dental handpiece has a powerhead assembly connected to a hollow handle portion including a tube supplying air under pressure, a water tube and an exhaust tube, a holding sleeve held to the hollow handle portion and a rotatably and detachable connecting means. The tube supplying air under pressure is...http://www.google.fr/patents/US4490113?utm_source=gb-gplus-shareBrevet US4490113 - Dental handpiece
