Irrigant flow beyond the insertion depth of an ultrasonically oscillating file in straight and curved root canals: visualization and cleaning efficacy.

Introduction: The purpose of this study was to evaluate the influence of the insertion depth of an ultrasonically oscillating file on the ability to remove dentin debris from simulated canal irregularities in an extracted tooth model of a straight root canal and its influence on the flow of irrigant in both straight and curved canals.

Methods: A tooth model with artificial depressions in 1 canal wall at 0.5, 2, 4, and 6 mm from the working length was used.