Fracture Resistance of K3 Nickel-Titanium Files Made from Different Thermal Treatments

Figure 3

SEM images of fractured surfaces of files after cyclic fatigue fracture test (a–f) and torsional fracture test (g–l). SEM images of lateral surface of unused files (m–o). (a, d, g, j, m) K3, (b, e, h, k, n) K3XF, and (c, f, i, l, o) K3H.

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