Objective: Different single-file instruments and kinematics have been introduced on the market. It is important to know the cyclic fatigue performance of these instruments in these new kinematics such as reciprocation of Optimum Torque Reverse (OTR) motion. The aim of this study was to evaluate the resistance to cyclic fatigue of F6 SkyTaper and OneShape used in continuous rotation (proper rotation) or in reciprocating OTR motion.
Methods: A total of forty-eight nickel-titanium files were tested. Twenty-four instruments of both brands were divided into two groups (n=12) on the basis of the motion tested: continuous rotation (group 1) or reciprocating OTR motion (group 2). Resistance to cyclic fatigue was determined by recording time to fracture (TtF) in a stainless steel artificial canal with a 60° angle of curvature and 5 mm radius of curvature. Data were analysed by two-way analysis of variance and post-hoc Bonferroni tests for multiple comparisons with P<0.05 as the level of significance.
Results: F6 SkyTaper showed higher TtF compared with OneShape, both in continuous and in OTR motion (P<0.0001). The two tested instruments showed higher cyclic fatigue resistance in reciprocating OTR motion than continuous rotation (P<0.0001).
Conclusion: OTR motion significantly improves cyclic fatigue resistance of the tested instruments. In addition, F6 SkyTaper showed higher cyclic fatigue resistance than OneShape in both motions.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7757954 | PMC |
| http://dx.doi.org/10.14744/eej.2017.17012 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Polyurethane-grafted graphene oxide from repurposed foam mattress waste.
RSC Adv
January 2025
Department of Chemistry, Carnegie Mellon University 4400 Fifth Avenue Pittsburgh PA 15213 USA
Polyurethanes (PU) make up a large portion of commodity plastics appearing in applications including insulation, footwear, and memory foam mattresses. Unfortunately, as thermoset polymers, polyurethanes lack a clear path for recycling and repurposing, creating a sustainability issue. Herein, using dynamic depolymerization, we demonstrate a simple one-pot synthesis for preparation of an upcycled polyurethane grafted graphene material (PU-GO).
View Article and Find Full Text PDFPrognostics of the knee osteoarthritis induced by cyclic loading activities. A model-based analysis.
Comput Methods Biomech Biomed Engin
January 2025
College of Engineering and Technology, American University of the Middle East, Egaila, Kuwait.
Repetitive mechanical stresses on the knee joint during daily activities accumulate fatigue damage in the articular cartilage (AC), leading to wear and knee osteoarthritis (KOA). Effective treatments remain limited, underscoring the need for predictive approaches to identify KOA early. This study proposes a mathematical model to estimate AC degradation under cyclic loading from walking.
View Article and Find Full Text PDFCharacterization of Fatigue Properties of Fiber-Reinforced Polymer Composites Based on a Multiscale Approach.
Polymers (Basel)
January 2025
Department of Mechanical Engineering, Hanyang University, 222 Wangsimri-ro, Seongdong-gu, Seoul 04763, Republic of Korea.
This study presents a methodology for characterizing the constituent properties of composite materials by back-calculating from the laminate behavior under fatigue loading. Composite materials consist of fiber reinforcements and a polymer matrix, with the fatigue performance of the laminate governed by the interaction between these constituents. Due to the challenges in directly measuring the properties of individual fibers and the polymer matrix, a reverse-engineering approach was employed.
View Article and Find Full Text PDFExperimental Investigation on Macroscopic and Microscopic Mechanical Properties of Geopolymer-Stabilized Macadam.
Materials (Basel)
January 2025
School of Civil Engineering, Central South University, Changsha 410075, China.
Geopolymer, as a promising inorganic binding material, holds potential for use in constructing base layers for highway pavements. This study aims to evaluate the mechanical properties of geopolymer-stabilized macadam (GSM) at both the micro- and macro-scale by a series of tests, demonstrating that high-Ca GSM is a high-quality material for pavement base layers. The results demonstrated that GSM exhibits outstanding mechanical and fatigue properties, significantly surpassing those of cement-stabilized macadam (CSM).
View Article and Find Full Text PDFStrain-Controlled Thermal-Mechanical Fatigue Behavior and Microstructural Evolution Mechanism of the Novel Cr-Mo-V Hot-Work Die Steel.
Materials (Basel)
January 2025
School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471023, China.
In response to the intensifying competition in the mold market and the increasingly stringent specifications of die forgings, the existing 55NiCrMoV7 (MES 1 steel) material can no longer meet the elevated demands of customers. Consequently, this study systematically optimizes the alloy composition of MES 1 steel by precisely adjusting the molybdenum (Mo) and vanadium (V) contents. The primary objective is to significantly enhance the microstructure and thermal-mechanical fatigue performance of the steel, thereby developing a high-performance, long-life hot working die steel designated as MES 2 steel.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!