Fluid material dispensing syringe

Abstract

A dental syringe ( 10 ) has a needle ( 11 ) affixed to a carpule holder ( 12 ), which carpule holder ( 12 ) is affixed to a power drive unit ( 13 ). A harpoon ( 20 ) is provided to affix the drive unit to the carpule plunger ( 32 ). The harpoon ( 20 ) is made of stainless steel or other hard, corrosion resistant, sterilizable, material. Harpoon 20 has a unique barb geometry and hardened, knife-like, edges ( 21 ). The syringe ( 10 ) may operate to divide the delivery of anesthesia into two phases. According to the method, during the first about 10 seconds of the injection, anesthetic is delivered at an extremely slow rate to maximize patient comfort. The injection rate then automatically increases to the preprogrammed rate associated with the injection type selected.

1 . A system for administering an anesthetic into a patient, the system comprising: 
 a container storing an anesthetic;    a needle; and    means for delivering the anesthetic through the needle at a first predetermined rate for a first predetermined time of between about 30 and 240 seconds.    
   
   
       2 . The system for administering an anesthetic into a patient as in  claim 1 , wherein the means for delivering the anesthetic further comprises means for a user to select the second predetermined rate.