INTRODUCTION Cyclic fatigue is the common reason for breakage of rotary instruments. This study was conducted to evaluate the effect of cryogenic treatment (CT) in improving the resistance to cyclic fatigue of endodontic rotary instruments. METHODS AND MATERIALS In this in vitro study, 20 RaCe and 20 Mtwo files were randomly divided into two groups of negative control and CT. CT files were st...

The aim of this study was to assess cyclic fatigue resistance in rotary nickel-titanium instruments after simulated clinical use in curved root canals (40-degree, 5-mm radius curve). Thirty-six RaCe rotary NiTi files, size #5, taper 0.04, were divided into 3 groups: Groups A, B and C with one, three and five cycles of use, respectively. Time to failure was recorded with a stopwatch in seconds a...

AIM To compare the cyclic fatigue resistance of HyFlex CM, Twisted Files (TF), K3XF, Race, and K3, and evaluate the effect of autoclave sterilization on the cyclic fatigue resistance of these instruments both before and after the files were cycled. METHODOLOGY Five types of NiTi instruments with similar size 30, .06 taper were selected: HyFlex CM, TF, K3XF, Race and K3. Files were tested in a...

ARTICLE INFO ABSTRACT Article Type: Original Article Introduction: The aim of this study was to compare several metallurgic properties of Neoniti instrument with four other commonly used endodontic rotary files. Methods and Materials: Neoniti A1 (25/0.08), RaCe (25/0.06), Mtwo (25/0.06), Twisted file (25/0.06) and ProTaper Next X2 (25/0.06) were examined by differential scanning calorimetry (DS...

introduction: this study compared the cleaning efficiency of mtwo, race and medin nickel-titanium (niti) rotary instruments. materials and methods: sixty mandibular molar mesial roots were selected with angle curvatures between 25-35 degrees and divided into three groups; each containing 20 teeth. canals were prepared with the rotary files and irrigated with 2.5% naocl solution after each instr...

statement of problem: microorganisms are essential for the development of periradicular diseases and are one of the major causative factors associated with endodontic treatment failures. different instruments and preparation techniques have been developed in endodontics to eliminate or reduce intracanal bacteria. purpose: the aim of this study was to compare the amount of remaining e. faecalis ...

introduction: to compare the cleaning effectiveness of k3 and race niti rotary systems with k-flexo file instruments during the preparation of curved canals in extracted human teeth. materials and methods: a total of 50 root canals of mandibular and maxillary molars with curvatures ranging between 25º and 35 º were divided in three groups of 15 each and 5 as negative control groups. canals were...

introduction: this study aimed to compare the efficacy of mtad, glyde and edta in removing the post-preparation smear layer and debris produced in apical third of curved molar root canals. materials and methods: forty extracted human maxillary first molars with curved mesiobuccal canals (30˚-35˚), similar root lengths and morphologies were divided into 3 experimental groups (n=12) and one contr...

OBJECTIVE The goal of present study was to determine the effect of different nickel-titanium file systems on the amount of apically extruded debris during endodontic retreatment: D-RaCe retreatment systems, EdgeFile XR retreatment rotary files, and Reciproc R40. MATERIALS AND METHODS Thirty-six single-rooted prepared mandibular premolar teeth were filled with Gutta-percha and AH Plus sealer. ...