introduction: this study aimed to perform a rigorous sample standardization and also evaluate the preparation of mesiobuccal (mb) root canals of maxillary molars with severe curvatures using two single-file engine-driven systems (waveone with reciprocating motion and oneshape with rotary movement), using micro-computed tomography (micro-ct). methods and materials: ten mb roots with single canal...

INTRODUCTION The purpose of this study was to examine the lifespan of one nickel-titanium (NiTi) rotary file when used in reciprocating motion and to compare the time required for its preparation of a curved root canal using both reciprocating and continuous motion. METHODS One hundred twenty curved canals from 60 extracted maxillary and mandibular molars were selected for measuring the mean ...

INTRODUCTION New designs and alloys and different motions have been introduced to increase the cyclic fatigue (CF) resistance of nickel-titanium (NiTi) files. The aim of this study was to compare the CF resistance of K3 (SybronEndo, Orange, CA), K3XF (SybronEndo), and TF (SybronEndo) files under continuous rotation and reciprocating motion. METHODS A total of 210 files (30-tip diameter, 0.06 ...

AIM To compare cyclic fatigue resistance of two geometrically similar nickel-titanium instruments, used in conditions similar to clinical use in reciprocating and continuous rotary motion. METHODOLOGY Four groups of eighteen instruments each, Reciproc(®) files sizes ISO 25 and 40 (R25 and R40) and Mtwo(®) files sizes ISO 25 and 40 (M25 and M40), were tested in reciprocating and continuous rot...

We consider a system of two coupled Brownian particles fluctuating between two states. The fluctuations are produced by both equilibrium thermal and external nonthermal noise, the transition rates depending on the interparticle distance. An externally induced modulation of the transition rates acts on the internal degree of freedom (the interparticle distance) and generates reciprocating motion...

INTRODUCTION The introduction of nickel-titanium (NiTi) files into clinical practice has improved the quality of canal shaping, but increasing the curvature of the root canal (or the diameter of the master instrument that prepares the full working length) could result in more transportation, straightening, and aberration of the canal. Nickel-titanium instruments are significantly safer and have...

AIM The aim of the present study was to compare the resistance to cyclic fatigue of Hyflex® (Coltene-Whaledent, Allstatten, Switzerland) size 40 taper.04 nickel titanium instruments used in continuous rotation versus the use with a reciprocating motion. The null hypothesis was that different file motions had no influence on the lifetime of instruments subjected to a cyclic fatigue test. METHO...

Aim:To compare the incidence of dentinal defects after preparation with reciprocating (Reciproc and WaveOne) and fullsequence rotary ProTaper Universal and Protaper Next instruments. Materials and methods:One hundred human mandibular premolars were randomly assigned to 5 groups (n = 20 teeth per group). The root canals were instrumented by using the reciprocating single-file systems Reciproc an...

BACKGROUND Spinal cord injury patients walk with a flexed trunk when using reciprocating gait orthoses. Reduction of trunk flexion during ambulation may produce an improvement in gait parameters for reciprocating gait orthosis users. OBJECTIVES To investigate the effect on kinematics and temporal-spatial parameters when spinal cord injury patients ambulate with an advanced reciprocating gait ...