A comparison of two reciprocating instruments using bending stress and cyclic fatigue tests.

The aim of this study was to comparatively evaluate the bending resistance at 45º, the static and dynamic cyclic fatigue life, and the fracture type of the WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) 25-08 and Reciproc (VDW, Munich, Germany) 25-08 instruments. A total of 60 nickel-titanium (NiTi) instruments (30 Reciproc and 30 WaveOne) from three different lots, each of which was 25 mm in length, were tested. The bending resistance was evaluated through the results of a cantilever-bending test conducted using a universal testing machine.

Temperature changes on the root surfaces of mandibular incisors after an 810-nm high-intensity intracanal diode laser irradiation.

Unlabelled: Temperature changes caused by laser irradiation can promote damage to the surrounding dental tissues. In this study, we evaluated the temperature changes of recently extracted human mandibular incisors during intracanal irradiation with an 810-nm diode laser at different settings. Fifty mandibular incisors were enlarged up to an apical size of ISO No.

Bactericidal effects of two parameters of Er:YAG laser intracanal irradiation: ex-vivo study.

The success of endodontic treatment depends on the complete elimination of microorganisms from the root canal system, thus the search for new procedures to eliminate them is justified. The aim of this study was to assess bacterial reduction after intracanal irradiation with the Er:YAG laser. The canals of 70 extracted human maxillary canines were prepared up to file #40 using 1% NaOCl, irrigated with 17% EDTA, and then washed with physiological solution activated by ultrasound.

The assessment of infection control in dental practices in the municipality of São Paulo.

Objective: The goal of this study was to evaluate the infection control measures actually implemented by dental surgeons during dental practice, as patients and professionals are exposed to high biological risk in dental care environments.

Method: 614 questionnaires (90.69%) were answered by professionals registered in updating or in post-graduate courses in the Municipality of São Paulo.

Accuracy of working length determination using 3 electronic apex locators and direct digital radiography.

Objectives: The objectives of this study were to assess the accuracy of working length determination using 3 electronic apex locators and direct digital radiography and to compare the results with those obtained using the visual method (control measurement).

Study Design: Twenty extracted human maxillary premolars were selected: 17 two-rooted and 3 single-rooted (total of 37 canals). Working length was measured using electronic apex locators Elements Diagnostic, Root ZX, and Just II.

Accuracy of three electronic apex locators in the presence of different irrigating solutions.

The present study compared the accuracy of three electronic apex locators (EALs) - Elements Diagnostic®, Root ZX® and Apex DSP® - in the presence of different irrigating solutions (0.9% saline solution and 1% sodium hypochlorite). The electronic measurements were carried out by three examiners, using twenty extracted human permanent maxillary central incisors.

Apical leakage of three resin-based endodontic sealers after 810-nm-diode laser irradiation.

Objective: To evaluate the influence of 810-nm-diode laser irradiation, applied before root canal filling, on apical sealing ability of three different resin-based sealers (AH Plus, EndoRez, and RealSeal).

Background: Lasers have been widely used in endodontics. The dentin wall changes caused by laser irradiation could improve the sealing ability of endodontic cements.

Morphologic changes and removal of debris on apical dentin surfaces after Nd:YAG laser and diode laser irradiation.

Objective: To verify the effects of laser energy on intracanal dentin surfaces, by analyzing the morphologic changes and removal of debris in the apical third of 30 extracted human teeth, prepared and irradiated with the Nd:YAG laser and diode laser.

Background Data: Lasers have been widely used in endodontics. The morphologic changes in dentin walls caused by Nd:YAG and diode laser irradiation could improve apical seals and cleanliness.

Influence of Nd:YAG and diode laser irradiation on apical sealing when associated with AH plus and EndoREZ endodontic cements.

Objective: This study aims to evaluate the influence of Nd:YAG and diode laser irradiation on apical sealing when applied before root canal filling done with two different resin-based cements (AH Plus and EndoREZ).

Background Data: Lasers have been widely used in endodontics. The morphologic changes in dentin walls caused by Nd:YAG and diode laser irradiation could improve sealing ability of endodontic cements.

Study of the areas and thicknesses of mesiobucal root canals prepared by three endodontic techniques.

The purpose of this study was to compare, in vitro, by means of computerized analysis of digital radiographic images, the anatomic alterations produced in the mandibular molar tooth dentinal walls of mesiobucal canals with severe curvature by three different endodontic techniques: Progressive Preparation, Staged and Serial Preparation. A selection was made of 45 extracted, human, mandibular molars, with root curvatures greater than 25 degrees. They were divided into three groups for every technique studied, which were then sub-divided into three sub-groups in accordance with the position of the curvature along the root: cervical, median or apical.

Location and angulation of curvatures of mesiobucal canals of mandibular molars debrided by three endodontic techniques.

The aim of this study was to assess the correlation between the degree of angulation and the position of root curvatures and their influence on the comparative results between the performances of the Progressive, Staged and Serial Preparation Techniques. The mesiobucal canals of 70 extracted mandibular molars were filled with a radiological contrast of 100% Barium sulphate and radiographed with a direct digital radiographic system, in an apparatus that guarantees that the samples remain in the same spatial position at all times. The images were then analyzed in the Coreldraw 10 program (MicroSafe, RJ, Brasil) in accordance with two criteria: the methods of Berbert, Nishiyama(1) (1994) and Schneider11 (1971) to determine the position and the angle of the root curvatures, respectively.