Patent ID: 8916009

Claim:
A method for manufacturing a nonlinear non-superelastic file formed of a material that includes nickel and titanium, the method comprising the steps of: providing a superelastic file having a shaft and a file axis; providing a fixture including a file groove being defined by one or more displacement members, the file groove configured for receiving the shaft; inserting at least a portion of the shaft into the fixture along the file groove, the portion of the shaft including a first portion of the shaft; contacting the first portion of the shaft with a first displacement member of the one or more displacement members such that the first portion of the shaft is displaced from the file axis thereby forming a first offset portion of the shaft; and heating the portion of the shaft while inserted in the fixture to a temperature from about 450° C. to about 550° C. for a time period from about 5 minutes to about 20 minutes to shape-set the portion of the shaft thereby forming a shape-set nonlinear file; cooling the portion of the shaft to form the shape-set nonlinear file and heating at least a portion of the cooled shape-set nonlinear file to a temperature from about 300° C. to about 600° C. for a period of time from about 20 minutes to about 120 minutes to alter the austenite finish temperature thereby forming a shape-set non-superelastic nonlinear file, and wherein the altered austenite finish temperature of the shape-set non-superelastic nonlinear file is from about 20° C. to about 40° C.