Introduction: This study evaluated the influence of flexibility and reciprocating movement on the fatigue life of endodontic instruments subjected to static and dynamic tests.
Methods: The rotary nickel-titanium instruments used in this study were Reciproc and Mtwo. The instruments were initially subjected to a cantilever-bending test and then to static and dynamic fatigue tests. Reciproc instruments were operated in reciprocating movement, whereas Mtwo instruments were worked in continuous rotation.
Results: The means of bending resistance (maximum load in grams) of the instruments were 274.9 for Reciproc and 429 for Mtwo. The mean times (in seconds) to fracture of the instruments subjected to static and dynamic tests were 214.5 (static) and 286.3 (dynamic) for Reciproc and 38.9 (static) and 99 (dynamic) for Mtwo. The Student's t test revealed significant differences in all tests (P < .05).
Conclusions: The results of the present study showed longer fatigue life for instruments with higher flexibility, driven by reciprocating movement, and in the dynamic testing model. These findings reinforce the assumption that use of reciprocating movement is a means to prolong the fatigue life of rotary nickel-titanium endodontic instruments during instrumentation of curved canals.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.joen.2012.11.048 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Laser speckle contrast imaging with principal component and entropy analysis: a novel approach for depth-independent blood flow assessment.
Front Optoelectron
January 2025
Institution of Physics, Saratov State University, Saratov, 410012, Russia.
Current study presents an advanced method for improving the visualization of subsurface blood vessels using laser speckle contrast imaging (LSCI), enhanced through principal component analysis (PCA) filtering. By combining LSCI and laser speckle entropy imaging with PCA filtering, the method effectively separates static and dynamic components of the speckle signal, significantly improving the accuracy of blood flow assessments, even in the presence of static scattering layers located above and below the vessel. Experiments conducted on optical phantoms, with the vessel depths ranging from 0.
View Article and Find Full Text PDFBasic Science and Pathogenesis.
Alzheimers Dement
December 2024
University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Background: The human brain is a complex inter-wired system that emerges spontaneous functional fluctuations. In spite of tremendous success in the experimental neuroscience field, a system-level understanding of how brain anatomy supports various neural activities remains elusive.
Method: Capitalizing on the unprecedented amount of neuroimaging data, we present a physics-informed deep model to uncover the coupling mechanism between brain structure and function through the lens of data geometry that is rooted in the widespread wiring topology of connections between distant brain regions.
Clinical Manifestations.
Alzheimers Dement
December 2024
Memory & Aging Center, Department of Neurology, University of California in San Francisco, San Francisco, CA, USA.
Background: Recent international work suggests that more precise subtyping within frontotemporal dementia (FTD) syndromes leads to better prediction of pathology, supporting individualized disease-specific treatments. Recent studies emphasize that identification of one such subtype, semantic behavioral variant FTD (sbvFTD), relies in part on measuring emotion recognition abilities.
Method: In order to evaluate the effectiveness of current tools, we compared the brief video-based Dynamic Affect Recognition Test (DART) against the TASIT Emotion Evaluation (EET) and Comprehensive Affect Testing System Affect Matching tests.
Adaptive Radiative Thermal Management Using Transparent, Flexible Ag Nanowire Networks.
ACS Appl Mater Interfaces
January 2025
ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia.
Effective heat management is critical for improving energy efficiency and minimizing environmental impact. Passive radiative heat management systems rely on specific materials and design configurations to naturally modulate temperature, enhance system reliability, and decrease operational costs by modulating infrared light. However, their static nature proves insufficient in dynamic settings experiencing significant temperature fluctuations.
View Article and Find Full Text PDFStatic and dynamic balance in physically active females with pronated feet.
Physiother Theory Pract
January 2025
Department of Sports Medicine, Chair of Clinical Physiotherapy, Faculty of Health Sciences, Medical University of Lublin, Lublin, Poland.
Background: Understanding and assessing static and dynamic balance and their relationship with the function of the medial longitudinal arch of the foot is crucial for people with pronated feet.
Purpose: This study aimed to assess the medial longitudinal arch height and postural balance in physically active females with pronated feet.
Methods: A case-control study.
Want 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!