We evaluated the influence of manual preflaring and torque on the failure rate of rotary nickel-titanium ProTaper instruments Shaping 1 (S1), Shaping 2 (S2), Finishing 1 (F1), and Finishing 2 (F2). These factors were evaluated using an in vitro method by calculating the mean number of Endo-Training-Blocks shaped before file breakage under different conditions. Group A (S1 on simulators with no ...

OBJECTIVE To investigate the influence of three different rotary systems for cervical flaring on establishment of the real working length. MATERIAL AND METHODS Thirty mandibular first molars were submitted to conventional endodontic access and initial working length measurement, followed by irrigation/suction of the pulp chamber with 5% sodium hypochlorite. Teeth were randomly divided into 3 ...

Background: In children, caries removal by means of conventional rotary instruments is often associated with pain and discomfort. An alternative method to conventional caries removal by means of rotary instruments is the use of chemo-mechanical caries removal agents. Aim: To evaluate and compare the efficacy of two chemomechanical caries removal agents Carisolv and Papacarie in reducing carioge...

Background: The objective of the present study was to measure and compare how length CM Gold Wire Blue NiTi alloy endodontic rotary files impacts their resistance cyclic fatigue. Methods: A total 40 sterile were chosen allocated following groups: (A) 25.06 wire files, 31 mm in (n = 10); (B) 25 (C) 21 (D) 17 10). specialized device designed using artificial root canal systems made from stainless...

INTRODUCTION The aim of the present work was to evaluate the resistance to flexural fatigue of Reciproc R25 nickel-titanium files, 25 mm, used in continuous rotation motion or reciprocation motion, in dynamic assays device. METHODS Thirty-six Reciproc R25 files were divided into 2 groups (n = 18) according to kinematics applied, continuous rotary (group CR) and reciprocation motion (group RM)...

The purpose of this study was to compare the incidence and longitudinal propagation of dentin defects after gutta-percha removal with hand and rotary instruments using microcomputed tomography. Twenty mandibular incisors were prepared using the balanced-force technique and scanned in a 19.9 μm resolution. Following filling with the lateral compaction technique, gutta-percha was removed with Pro...

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...

INTRODUCTION The aim of this study was to assess the shaping potential of a novel nickel-titanium instrument, the self-adjusting file (SAF), in long oval root canals in distal roots in mandibular molars. METHODS Twenty mandibular molars with long oval distal root canals were selected and scanned preoperatively and postoperatively by using micro-computed tomography at an original resolution of...

We report a significant advance in space robotics design based on innovation of 3D composite structures and piezoelectric actuation. The essence of this work is development of a new all-composite robotic manipulator utilizing rotary ultrasonic motors (USM). “MarsArmII“ is 40% lighter than a prior “MarsArmI” JPL design based in more massive, bulky hybrid metal-composite, joint-link system archit...

A polygon A in a configuration C is called rotary if C admits an automorphism which acts upon A as a one-step rotation. We study rotary polygons and their orbits under the group of automorphisms (and antimorphisms) of C. We determine the number of such orbits for several symmetry types of rotary polygons in the case when C is flag-transitive. As an example, we provide tables of flag-transitive ...