Effects of clinical use of NiTi reciprocating instruments on cyclic and torsional resistance, and on roughness.

The aim of the present study was to evaluate the cyclic fatigue, torsional resistance and surface roughness of Reciproc R25 instruments in four different situations, namely as new instruments and as instruments tested after clinical preparation of one, two or three maxillary molars with four root canals. The total time required to perform each root canal preparation was recorded. Cyclic fatigue resistance was determined by the time to fracture using a customized testing device (n = 10 per group).

Cyclic Fatigue and Torsional Resistance of Four Martensite-Based Nickel Titanium Reciprocating Instruments.

Objective: To evaluate cyclic fatigue and torsional resistance of Reciproc Blue R25 (VDW, Munich, Germany), WaveOne Gold Primary (Dentsply Maillefer, Ballaigues, Switzerland), ProDesign R (Easy Equipamentos Odontológicos, Belo Horizonte, Brazil), and X1 Blue File (MK Life, Porto Alegre, Brazil) nickel titanium (NiTi) martensite reciprocating instruments.

Methods: In each group, ten instruments were tested for cyclic fatigue resistance using a stainless-steel artificial canal (curvature angle of 80° and radius of 3 mm) and ten instruments for torsional failure according to ISO 3630-1 standard. The surface of the fractured instruments was examined under scanning electron microscopy (SEM) at ×250 magnification.

Evaluation of oral care protocols practice by dentists in Rio de Janeiro towards HIV/AIDS individuals.

Background: The aim of this study was to evaluate the dentists' knowledge and practice regarding HIV positive individuals' oral care in Rio de Janeiro State.

Methods: Dentists from Rio de Janeiro State (n = 242) answered an electronic questionnaire on biosafety procedures, oral manifestations of AIDS, and knowledge of HIV infection. Collected information was stratified by gender, and data were analyzed using Chi-square and t tests.

Mechanical Properties of Anatomic Finishing Files: XP-Endo Finisher and XP-Clean.

The aim of the present study was to evaluate the cyclic fatigue of two anatomic finishing files: XP-Endo Finisher and XP-Clean. Roughness pattern and the micro-hardness of the files were also assessed. Instruments were subjected to cyclic fatigue resistance measuring the time to fracture in an artificial stainless-steel canal with a 60° angle and a 5-mm radius of curvature.

Micro-CT evaluation of different final irrigation protocols on the removal of hard-tissue debris from isthmus-containing mesial root of mandibular molars.

Objectives: This study aimed to compare four final irrigation protocols (passive ultrasonic irrigation [PUI], EndoVac, Self-Adjusting File [SAF] and EasyClean) on the removal of accumulated hard-tissue debris (AHTD) from mesial canals of mandibular molars through microcomputed tomographic (micro-CT) analysis.

Materials And Methods: Forty mesial roots of mandibular molars presenting isthmuses type I or III were scanned in a micro-CT device and instrumented up to Reciproc R40 instrument. After the completion of canal preparations, root canals of each group were submitted to a final rinse using 20 mL of solution (16 mL of 5.

Micro-computed tomographic evaluation of canal retreatments performed by undergraduate students using different techniques.

Objectives: This study evaluated the amount of remaining root canal filling materials after retreatment procedures performed by undergraduate students using manual, rotary, and reciprocating techniques through micro-computed tomographic analysis. The incidence of instrument fracture and the instrumentation time were also evaluated.

Materials And Methods: Thirty maxillary single rooted teeth were prepared with Reciproc R25 files and filled with gutta-percha and AH Plus sealer by the continuous wave of condensation technique.

Cyclic fatigue using severely curved canals and torsional resistance of thermally treated reciprocating instruments.

Objectives: To evaluate the cyclic fatigue using severely curved canals and torsional resistance of ProDesign R (Easy Equipamentos Odontológicos, Belo Horizonte, MG, Brazil), Reciproc Blue (VDW, Munich, Germany), and WaveOne Gold (Dentsply Maillefer, Ballaigues, Switzerland) reciprocating instruments MATERIALS AND METHODS: Twenty instruments of the ProDesign R (25/0.06) system, 20 instruments of the Reciproc Blue (25/0.08v) system, and 20 instrument of the WaveOne Gold (25/0.

Postoperative Pain after Endodontic Retreatment Using Rotary or Reciprocating Instruments: A Randomized Clinical Trial.

Introduction: The aim of this randomized clinical trial was to evaluate the influence of rotary or reciprocating retreatment techniques on the incidence, intensity, duration of postoperative pain, and medication intake.

Methods: After power analysis calculations, 65 patients who needed endodontic retreatment were randomly assigned to 1 of 2 groups according to the instrumentation system used: Mtwo (VDW, Munich, Germany) or Reciproc (VDW). Retreatments were performed in a single visit by an endodontic specialist.

Self-adjusting file cleaning-shaping-irrigation system improves root-filling bond strength.

Introduction: The aim of the present study was to assess the bond strength of root fillings in oval-shaped canals prepared with the self-adjusting file (SAF) system.

Methods: A careful specimen selection resulted in 2 equal groups, each consisting of 12 extracted mandibular canines with oval canals that had vital pulps before extraction. One group was subjected to the SAF protocol, and the other group underwent conventional protocol, which was the ProTaper system with syringe-needle irrigation.

Influence of curvature location along an artificial canal on cyclic fatigue of a rotary nickel-titanium endodontic instrument.

Objectives: This study evaluated the effects of curvature location along an artificial canal on cyclic fatigue (CF) of an Mtwo rotary instrument, verifying the number of cycles to fatigue fracture (NCF) and morphologic characteristics of the fractured instruments.

Study Design: CF testing of instruments was performed in artificial canals with curvature radii of 10 mm and arc lengths of 11 mm. Mtwo rotary instruments size 40, 0.

Cyclic fatigue of ProTaper instruments.

The present work evaluated the influence of the curved segment length of artificial root canals (the arc) and the number of cycles necessary to fracture engine-driven nickel-titanium endodontic instruments. ProTaper F3 25-mm files at 250 rpm were used in two artificial canals. The artificial canals were made of stainless steel with an inner diameter of 1.