Dental syringe for painless injections - with simultaneous penetration of needle and ejection of anaesthetic liq

摘要

Dental syringe, for painless injections, has a striker, operated by a spring, which on hitting a small tilting component, pivoting on an axis, pushes the curved, double-pointed needle through the orifice of the casing; at the same time the tilting component exerts pressure on a small rubber capsule which covers the end of a carriage contg. an anaesthetic liq. The small quantity of liq. reaching the end of the needle renders the penetration of the needle into the organic tissues quite painless; the injection is then continued, as with an ordinary syringe, by pushing the piston to inject the liq. contd. in the cartridge.