As compared with continuous rotary systems, reciprocating motion is believed to increase the fatigue resistance of NiTi instruments. We compared the cyclic fatigue and torsional resistance of reciprocating single-file systems and continuous rotary instrumentation systems in simulated root canals. Eighty instruments from the ProTaper Universal, WaveOne, MTwo, and Reciproc systems (n = 20) were s...

INTRODUCTION To evaluate the efficacy of NiTi mechanical rotary instrumentation and Hedstrom file for gutta-percha/sealer removal computed tomography (CT) was utilized in vitro. MATERIALS AND METHODS Thirty extracted human single rooted teeth, each with a single canal were selected. The samples were decoronated with a double faced diamond disk to have 17-mm root; teeth roots were instrumented...

INTRODUCTION Oval-shaped canals represent a challenge for rotary nickel-titanium (NiTi) files because buccal and/or lingual recesses are commonly left uninstrumented. The aim of the present study was to evaluate the debridement quality of the Self-Adjusting File (SAF) system in oval canals and compare it with the debridement achieved by a commonly used NiTi rotary system. METHODS A careful sp...

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...

INTRODUCTION A preparation technique with only 1 single instrument was proposed on the basis of the reciprocating movement of the F2 ProTaper instrument. The present study was designed to quantitatively assess canal preparation outcomes achieved by this technique. METHODS Twenty-five extracted human mandibular first molars with 2 separate mesial root canals were selected. Canals were randomly...

OBJECTIVES The purpose of this study was to compare in-vitro the amount of debris extruded apically from extracted teeth, using K3, Protaper rotary instruments and manual step-back technique. METHODS Forty five human single-rooted mandibular premolar teeth were randomly divided into 3 groups. The teeth in 3 groups were instrumented until reaching the working length with K3, Protaper rotary in...

Background and aims. The superiority of rotary systems has been reported in several clinical studies on permanent teeth. This study consisted of radiographic assessment and chair time of rotary instruments in the pulpectomy of primary second molar teeth. Materials and methods. In this randomized controlled clinical study, 46 children, 3-6 years of age, were selected. The patients were divided r...

INTRODUCTION Rotary nickel-titanium instruments have multiple advantages but with the risk of more fractures because of flexure or torsion. Alternating rotation appears to be an alternative to continuous rotary movement. The objective of this study was to determine the influence of the type of instrument rotation on the frequency of fractures or deformation. METHODS Instrumentation was perfor...

introduction: the purpose of the present study was to quantify and compare the amount of extruded debris from apical foramen after instrumentation of the root canal system with hand and rotary instruments. materials and methods: root canals of forty five fresh extracted single rooted human teeth with mature apexes and less than 15 degree of root curvature were instrumented in group a with stain...

AIM To compare ex vivo various parameters of root canal preparation using a manual technique and six different rotary nickel-titanium (Ni-Ti) instruments (FlexMaster, System GT, HERO 642, K3, ProTaper, and RaCe). METHODOLOGY A total of 147 extracted mandibular molars were divided into seven groups (n = 21) with equal mean mesio-buccal root canal curvatures (up to 70 degrees), and embedded in ...