In this study, curved maxillary molar root canals were instrumented with RaCe rotary system to evaluate: 1. the occurrence of canal transportation using a radiographic platform; 2. the action of the instruments on the dentin walls, centering ability and canal enlargement by analysis of digital images; and the percentage of regular dentin surfaces and debris within the canal by histological anal...

OBJECTIVES Glide path preparation is recommended to reduce torsional failure of nickel-titanium (NiTi) rotary instruments and to prevent root canal transportation. This study evaluated whether the repetitive insertions of G-files to the working length maintain the apical size as well as provide sufficient lumen as a glide path for subsequent instrumentation. MATERIALS AND METHODS The G-file s...

Asymmetric cell division plays an indispensable role during corticogenesis for producing new neurons while maintaining a self-renewing pool of apical progenitors. The cellular and molecular determinants favouring asymmetric division are not completely understood. Here, we identify a novel mechanism for generating cellular asymmetry through the active transportation and local translation of Cycl...

Aim: the aim of this study was to investigate the shaping ability of thermomechanically treated files manufactured by twisting (Twisted files) and compare it to conventional rotary system (K3, Sybron Endo, Orange, CA) in S-shaped canals, including formation of ledges, zipping, elbow, outer widening, danger zone, perforation and file deformation. Materials & Methods: Forty S-Shaped canals in res...

BACKGROUND Root canal shaping without any procedural error is of the utmost preference. Therefore, the purpose of this study was to use micro-computed tomography to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files. MATERIAL AND METHODS Sixty extracted upper second premolars were selected and were divided into 2 groups of 30. Be...

CONTEXT AND AIMS The purpose of this study was to compare and evaluate the shaping ability of ProTaper (PT) and Self-Adjusting File (SAF) system using cone-beam computed tomography (CBCT) to assess their performance in oval-shaped root canals. MATERIALS AND METHODS Sixty-two mandibular premolars with single oval canals were divided into two experimental groups (n = 31) according to the system...

objective: knowledge about the internal anatomy of the root canal and apical foramen is a critical prerequisite for root canal therapy and is necessary for the success of endodontic treatment. this study aimed to determine the distance of apical foramen from the anatomical apex and apical constriction, evaluate the deviation of apical foramen from the anatomical apex and specify the most common...