The aim of this work was to show the management of severe curvatures done with the new generation of rotating files through a safe and predictable protocol.
Three clinical cases were described. A safe protocol was explained using the latest generation of rotating files for the shaping of the anatomy of complex root canals. All the cases presented 90°, 45° curvatures and/or double curvatures.
The instrumentation of canals increased their surface area and volume. All the cases with 90° and 45° curvatures were optimally shaped.
With the help of rotating files in the martensitic alloy, it is possible to work safely, while avoiding the risk of file separation, even in root canals with severe curvatures, thus achieving success even in complex clinical cases.
Keywords: Endodontics, Curvatures, Modern Ni-Ti files, Shaping, HyFlex, Cyclic fatigue.