Incidence of Dentinal Defects During Root Canal Preparation Using a Single File Preparation System (An in Vitro Study

Abstract

Summary and Conclusion NiTi instruments are used in rotational motion and rotational force is applied to root canal walls. These NiTi instruments increase the risk of dentinal defects in root dentine especially in the apical portion of the root. These dentinal defects are in the form of craze lines, incomplete cracks, and complete cracks. They act as areas of stress concentrations and crack initiation. There is a specific torque limit (close to the limit of elasticity) be set for each instrument size and type. Thus, the manufacturers recommend different torque settings for different file sizes. The aim of the present study was to detect the dentinal damage caused by two different single file rotating systems with two different torque settings. Sixty mandibular first molars were collected, degree of curvatures were calculated for each tooth and evenly distributed among different groups. The access cavity and coronal flaring by Neoniti C1 was done. They were prepared by One Shape file system in all mesiobuccal canals and Neoniti A1 in all mesiolingual canals.