Introduction. The purpose of this study was to compare the taper variation in root canal preparations among Twisted Files and PathFiles-ProTaper .08 tapered rotary files to current standards. Methods. 60 root canals with severe angle of curvature (between 25° and 35°) and short radius (r < 10 mm) were selected. The canals were divided randomly into two groups of 30 each. After preparation with ...

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 ...

The tapered CdS nanobelts and CdSe nanowires were prepared by hydrogen-assisted thermal evaporation method. Different supersaturation leads to two different kinds of 1D nanostructures. The PL measurements recorded from the as-prepared tapered CdS nanobelts and CdSe nanowires show only a bandgap emission with relatively narrow full-width half maximum, which means that they possess good optical p...

Abstract In this paper, nonlinear dynamic snap-through buckling and vibration behavior of the thermally post-buckled functionally graded (FG) porous nanobeams subjected to static sudden mechanical loads are investigated utilizing nonlocal elasticity theory. The physical properties nanobeam considered be functions temperature based on Touloukian model. addition, describe FG materials, two differ...

statement of problem: various factors are involved in causing inflammation following root canal treatment. controlling these factors may relieve the related pain. one of these factors is extrusion of debris beyond the apex. although debris extrusion happens in all instrumentation techniques, researchers have declared that in coronal flaring technique, there is minimum debris extrusion. purpose:...

It was the aim of this study to investigate the incidence of file breakage and distortion when the ProTaper, K3 Endo, and ProFile systems were used to instrument canals in the severely curved roots of extracted molars. Forty-five roots of extracted mandibular and maxillary molars with curvatures between 40 and 75 degrees were chosen for this study. The canals in group 1 were instrumented with t...

The teaching of advanced endodontic courses at the predoctoral level is common, but it can be difficult to assess teaching effectiveness. Advanced modules placed later in the dental curriculum provide the opportunity to introduce a new topic, revisit and reinforce concepts learned previously, and instill the notion of lifelong learning. At any level, the introduction of new techniques to novice...

High throughput DNA sequencing has been performed by using a microfabricated 96-channel radial capillary array electrophoresis (microCAE) microchannel plate detected by a 4-color rotary confocal fluorescence scanner. The microchannel plate features a novel injector for uniform sieving matrix loading as well as high resolution, tapered turns that provide an effective separation length of 15.9 cm...

F1-ATPase (F1) is a reversible ATP-driven rotary motor protein. When its rotary shaft is reversely rotated, F1 produces ATP against the chemical potential of ATP hydrolysis, suggesting that F1 modulates the rate constants and equilibriums of catalytic reaction steps depending on the rotary angle of the shaft. Although the chemomechanical coupling scheme of F1 has been determined, it is unclear ...