Objective: To compare torsional fracture of three different types of nickel-titanium rotary instruments ProTaper, Hero642 and Mtwo by making a stimulate models in vitro.
Methods: Through the establishment of model in vitro, compared the different time with 3 kinds of nickel titanium file in cutting-edge bound occurs, and to observe the section of fractured instruments by scanning electron microscope.
Results: The resistence to torque was different from three types of nickel titanium instruments. The time to fracture of Mtwo was significantly longer than ProTaper's and Hero642's, but ProTaper's and Hero642's had no significant difference. Three kinds cross-sectional design were different, a lot of toughness nests were seen in broken surface. Most of them were ductile fracture. Time to fracture was influenced by the quality disfigurement.
Conclusion: The resistance to torque of Mtwo was better than ProTaper and Hero642. The lifespan was influenced by the design of cross-section. The quality disfigurement of the files reduced the resistance to flexual fatigue.
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Ophthalmic Physiol Opt
January 2025
School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia.
Purpose: To assess the repeatability of lipid layer thickness (LLT) measurement using the LipiView® interferometer after daily disposable contact lens (CL) wear and correlation with ocular comfort in soft contact lens wearers.
Methods: A prospective study was conducted over two consecutive months, wherein CL wearers (n = 20) wore either Somofilcon A or Verofilcon A daily disposable CLs in a crossover design, switching lenses after 1 month. The pre-corneal tear film LLT was measured at the end of each month after CLs had been worn for at least 6 h.
J Coll Physicians Surg Pak
January 2025
Department of Stomatology, The Second People's Hospital of Hefei and Hefei Hospital Affiliated to Anhui Medical University, Hefei, Anhui, China.
Objective: To investigate the effects of bulk-fill, resin-based composite types (high or low viscosity) on the internal adaptation of Class V restorations.
Study Design: Experimental study. Place and Duration of the Study: Hefei Stomatological Hospital, Hefei, China, from October 2022 to December 2023.
Cardiooncology
January 2025
Dept of Oncology Tier 2 Canada Research Chair, University of Alberta, Alberta, Canada.
Background: With early detection and improvements in systemic and local therapies, millions of people are surviving cancer, but for some at a high cost. In some cancer types, cardiovascular disease now competes with recurrent cancer as the cause of death. Traditional care models, in which the cardiologist or oncologist assess patients individually, do not address complex cancer and cardiovascular needs.
View Article and Find Full Text PDFSci Rep
January 2025
Colloid Chemistry, Department of Chemistry, University of Konstanz, Universitaetsstrasse 10, 78464, Konstanz, Germany.
Complex structures can be understood as compositions of smaller, more basic elements. The characterization of these structures requires an analysis of their constituents and their spatial configuration. Examples can be found in systems as diverse as galaxies, alloys, living tissues, cells, and even nanoparticles.
View Article and Find Full Text PDFChem Asian J
January 2025
China Three Gorges University, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, College of Materials and Chemical Engineering, China Three Gorges University, CHINA.
The Keggin clusters are one kind of the most representative molecular structures in the field of metal-oxo clusters. Although the different types of Keggin clusters with various components were reported, the research about γ-Keggin isomer remains less developed. This is ascribed to the difficulty in obtaining the stable pure γ-Keggin cluster for the structural isomerization.
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