The influence of taper on rotatory endodontic NiTi instruments related to torsion failure

Abstract

The aim of this work was to compare the angular deflection at failure and the maximum torque of NiTi rotatory instruments with the same size, same trademark and different tapers. The instruments were submitted to clockwise torsional mechanical tests. The values were submitted to statistical analisys and the results showed that the taper of helical shaft influenced the angular deflection and the maximum torque at failure. The angular deflection increased with the taper reduction, although the maximum torque at failure decreased with the taper reduction.