introduction: the aim of this study was to evaluate root canal anatomy of mandibular first molars (mfm) in a selected iranian population using clearing technique. methods and materials: a total of 150 extracted mfms were cleared. the root canal morphology (including the root numbers and root length) and the anatomy of the root canal system (including is the number and type of canals based on ve...

introduction: root canal preparation is an important process in endodontic therapy. nickel-titanium (niti) rotary file system can be used in single length technique (simultaneous technique) without early coronal enlargement, as well as in crown-down method. the purpose of this in vitro study was to compare single length with crown-down methods’ shaping ability using mtwo niti files . materials ...

INTRODUCTION This study evaluated the effects of 2 different kinematics rotary nickel-titanium (NiTi) systems, Twisted File (TF), a continuous rotation full-sequence system, and WaveOne (WO), a reciprocating single-file system, on transportation, curvature, and volumetric changes of curved root canals by using cone-beam computed tomography. METHODS Forty mesiobuccal canals of mandibular molar...

In this paper are determined the principal curvatures and principal curvature lines on canal surfaces which are the envelopes of families of spheres with variable radius and centers moving along a closed regular curve in R3. By means of a connection of the differential equations for these curvature lines and real Riccati equations, it is established that canal surfaces have at most two isolated...

In this paper are determined the principal curvatures and principal curvature lines on canal surfaces which are the envelopes of families of spheres with variable radius and centers moving along a closed regular curve in R. By means of a connection of the differential equations for these curvature lines and real Riccati equations, it is established that canal surfaces have at most two isolated ...

canal preparation generates a substantial amount of debris and smear layer (sl). the size and taper of the master apical file (maf) affects on penetration of irrigants and subsequently canal cleaning efficacy. the aim of this study was to evaluate the effect of maf size and taper on penetration of irrigants to the apical third of curved mesiobuccal (mb) canals of mandibular first molars.eighty-...

Introduction: The purpose of this in-vitro study was to compare shaping ability of NiTi rotary Mtwo and FlexMaster with stainless steel hand K-Flexofile in curved root canals of extracted teeth. Materials and Methods: Mesiobuccal canals of 45 mandibular molar teeth were balanced into three groups of 15 each, with respect to the Schneider angle, canal access angle, height, dis-tance and radiu...

introduction: the aim of this study was to compare digital and conventional radiography in determining the working length of dilacerated canals.methods: thirty nine human extracted single-rooted teeth with root curvature more than 35 degrees were included in this study. after access preparation, a file was inserted into the canal and advanced until the file tip was visualized at the foramen. wi...

INTRODUCTION The aim of this study was to compare the shaping ability of two single-file systems and conventional rotary instruments in severely curved root canals of extracted human molars. METHODS AND MATERIALS Mesiobuccal canals of 120 mandibular molars with angles of curvature ranging between 25(°) and 35(°) and radii of curvature from 5 to 9 mm, were divided into three groups (n=40). In ...

Cyclic fatigue of nickel-titanium, engine-driven instruments was studied by determining the effect of canal curvature and operating speed on the breakage of Lightspeed instruments. A new method of canal curvature evaluation that addressed both angle and abruptness of curvature was introduced. Canal curvature was simulated by constructing six curved stainless-steel guide tubes with angles of cur...