CM Wire and M-Wire instruments have increased austenite transformation temperatures.
The Af of CM Wire, M-Wire, twisted file, and conventional super-elastic NiTi wire are approximately
55°C, 50°C, 17°C, and 16°C-31°C, respectively [24-27]. The conventional super-elastic NiTi file has
an austenite structure [24-29], whereas NiTi file with thermal processing are in the martensite condition
at body temperature [24,26,27,30]. In addition, the critical stress for martensite reorientation of CM Wires
is 128 MPa-251 MPa at room temperature and 37°C, which is much lower than the critical stress for stress-induced
martensite transformation of the super-elastic wires (490 MPa -582 MPa) [24]. However, the maximum strain of CM
Wires before fracture (58.4%-84.7%) is much higher than that of the super-elastic wires (16.7%-27.5%). These results
indicate the superior flexibility of CM Wire compared with conventional superelastic NiTi wire.
