Root canal treatment tool and method for manufacturing the same

Abstract

The present invention relates to a root canal treatment tool that is formed in a shape of a rod and has a work portion formed in a predetermined length from a tip and a shank formed in a manner continuous with the work portion. The work portion has a shape memory characteristic in a range of a predetermined length from the tip and a superelastic characteristic in a remaining portion.

1 . (canceled)  
     
     
         2 . A method for manufacturing a root canal treatment tool, the method comprising the steps of: 
 subjecting a portion of a wire, provided with a superelastic characteristic by a first memory heat treatment, to a working of removing metal; and    subjecting a part in a certain length from a tip of the wire, of the portion to be provided with the working of removing metal to a second heat treatment to provide the part with a shape memory characteristic.    
     
     
         3 . The method for manufacturing a root canal treatment tool according to  claim 2 , wherein the step of subjecting the portion to a second heat treatment is performed by heat-protecting a portion not to be subjected to the second heat treatment by a cooling agent, and heating the portion to be subjected to the second heat treatment by predetermined means.  
     
     
         4 . A method for manufacturing a root canal treatment tool, the method comprising the steps of: 
 subjecting a portion of a wire, in a certain length from a tip of the wire, provided with a superelastic characteristic by a first memory heat treatment, to a second heat treatment to provide the portion of the wire with a shape memory characteristic; and    subjecting the portion of the wire having the shape memory characteristic, and a portion of the wire that is continuous with the portion having the shape memory characteristic and which has the superelastic characteristic, to working of removing metal.    
     
     
         5 . The method for manufacturing a root canal treatment tool according to  claim 4 , wherein the step of subjecting the portion to a second heat treatment is performed by heat-protecting a portion not to be subjected again to heat treatment by a cooling agent and heating the portion to be subjected to the second heat treatment by predetermined means.