Frequency response diagrams of a system include detailed and recognizable information about the structural and parameter effects of the transfer function model of the system. The information are qualitatively and quantitatively obtainable from simultaneous consideration of amplitude ratio and phase information. In this paper, some rules and relationships are presented for making use of frequenc...

Background and aims. During root canal preparation, debris extruded beyond the apical foramen may result in periapical inflammation and postoperative pain. To date no root canal preparation method has been developed that extrudes no periapical debris. The purpose of this study was to identify a system leading to minimal extrusion of debris from the apical foramen. The study was conducted to com...

Aim: To determine the centering ability of Twisted FileTM rotary system compared with ProTaper UniversalTM and ProFileTM rotary systems by evaluating preand postoperative cross-sectional images of the apical root canals third. Methods: Thirty mesiobuccal canals of human mandibular first molars were divided into three groups with 10 root canals each according to the instrument used: group 1, Pro...

Abstract: In this paper, we present the use of the laser tracker to aid the alignment of a Swing Arm Profilometer (SAP) and measure the length of the swinging arm, thus calibrating the operating radius of the SAP. The measurement uncertainty analysis is given. A laser tracker is used to align the SAP to ensure the path of the probe head passes through the rotary axis of the rotary table. By bui...

INTRODUCTION The purpose of this in vitro study was to assess the amount of apically extruded debris using rotary and reciprocating nickel-titanium instrumentation systems. METHODS Eighty human mandibular central incisors were randomly assigned to 4 groups (n = 20 teeth per group). The root canals were instrumented according to the manufacturers' instructions using the 2 reciprocating single-...

In the past, the design of light-driven single molecule rotary motors has been mainly guided by the modification of their ground-state conformational properties. Further progress in this field is thus likely to be achieved through a detailed understanding of light-induced dynamics of the system and the ways of modulating it by introducing chemical modifications. In the present theoretical work,...

This study evaluated the efficacy of 2 types of rotary instruments employed in association with sodium hypochlorite (NaOCl) or EDTA in removing calcium hydroxide (CH) residues from root canals dentin walls. Forty-two mandibular human incisors were instrumented with the ProTaper System up to F2 instrument, irrigated with 2.5% NaOCl followed by 17% EDTA and filled with a CH intracanal dressing. A...

OBJECTIVE To evaluate the impact of the type of root canal preparation, intraradicular post and mechanical cycling on the fracture strength of roots. MATERIAL AND METHODS eighty human single rooted teeth were divided into 8 groups according to the instruments used for root canal preparation (manual or rotary instruments), the type of intraradicular post (fiber posts- FRC and cast post and cor...

Achieving apical foramen patency through surgical maneuvers during the biomechanical preparation of root canals is a goal sought by several schools. The aim of this study was to evaluate the deformation of the foramen as a result of using stainless steel hand files and nickeltitanium rotary instruments for achieving patency. Forty recently extracted dental roots with single canals were calibrat...