Statement Of Problem: Laser sintering is commonly used for fabricating metal-ceramic restorations. The layer thickness of the sintering process may affect restoration adaptation. However, limited information is available regarding its impact.
Purpose: The purpose of this in vitro study was to compare the marginal and internal adaptation of laser-sintered cobalt-chromium single crown frameworks sintered with layer thicknesses of 25 and 50 μm.
Material And Methods: Thirty resin dies that represented prepared single molar abutment teeth were prepared by using a 3-dimensional printer and were divided into 3 groups (n=10) according to the method used for fabricating metal frameworks: group C, metal frameworks fabricated by using the lost-wax method (control); group L25, metal frameworks fabricated by using direct metal laser melting with a layer thickness of 25 μm; and group L50, metal frameworks fabricated by using direct metal laser melting with a layer thickness of 50 μm. After fabricating the metal frameworks, 15 vertical marginal discrepancy measurements were made in each axial region (mesial, distal, buccal, and lingual) using a stereomicroscope. Next, all the specimens were sectioned from the midline, and 5 internal discrepancy measurements were made in each internal region (inner marginal, axial, and occlusal). The data were analyzed statistically by using 1-way ANOVA, the Tukey honestly significant difference, and Tamhane T2 tests (α=.05).
Results: The highest marginal and internal discrepancy values were obtained for metal frameworks in group C, and these values were significantly different (P<.001) from those obtained for metal frameworks in the other 2 groups. No significant difference was observed in the marginal and internal discrepancy values of metal frameworks in groups L25 and L50.
Conclusions: These results indicate that layer thickness does not affect the adaptation of laser-sintered metal frameworks, yet both sintering parameters yielded significantly lower mean marginal discrepancy values than the cast group.
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http://dx.doi.org/10.1016/j.prosdent.2018.08.018 | DOI Listing |
Anal Chim Acta
March 2025
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, PR China. Electronic address:
Background: Based on the low volatility and refractory nature of Tetracycline (TC), excessive use leads to its continuous accumulation in water environments, posing serious risks to the ecological environment and human health. Although a very limited number of nanomaterials capable of simultaneously detecting and removing TC have been fabricated, they generally exist issues associated with a single detection signal ("on" or "off") or low adsorption rates with low adsorption capacities. As a result, it is crucial to develop a reliable technique to achieve ratiometric detection as well as rapid and efficient removal of TC.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Department of Cell and Molecular Biology, Faculty of Life Science and Biotechnology, Shahid Beheshti University, P.O. Box 19839-69411, Tehran, Iran. Electronic address:
The increasing prevalence of micropollutants like cationic and anionic dyes in wastewater creates an influential environmental challenge, mainly due to their toxic effects and persistence. Current methods often lack the efficiency and versatility to cope with a wide variety of contaminants. This study explores the modification of TEMPO-oxidized cellulose nanofibers (TOCNF) using (3-chloro-2-hydroxypropyl) trimethylammonium chloride (CHPTAC) to enhance their cationic properties.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
School of Materials Science and Engineering, Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, PR China. Electronic address:
The development of earth-abundant oxygen evolution reaction (OER) electrocatalysts with high activity and durability is critical for replacing noble-metal-based catalysts in the applications of scalable water electrolysis. A freestanding electrode architecture offers significant advantages over conventional coated powder forms due to enhanced kinetics and stability. However, precise control over electrode composition and the construction of uniformly distributed active sites within these electrodes remain challenging.
View Article and Find Full Text PDFFood Chem
January 2025
Agricultural Product Processing and Storage Lab, School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China. Electronic address:
The current study aimed to synthesize a ZIF-8 metal-organic framework loaded with the Rose Bengal (ZIF-8@RB) as the photodynamic sterilization ingredient to address the uncontrolled release of active ingredients in packaging films. The photodynamic controlled release packaging film was then prepared using a PVDF polymer matrix via uniaxial electrospinning. The microstructure, particle size, excitation wavelength, and singlet oxygen yield of ZIF-8@RB were examined.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
January 2025
Department of Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address:
This study introduces a novel approach to enhance the antibacterial properties of UIO-66 by incorporating both Thymol and ZnO nanoparticles within its framework which represents a significant advancement like exhibiting a synergistic antibacterial effect, providing a prolonged and controlled release, and mitigating cytotoxicity associated with the release of free ZnO nanoparticles by combining these two antimicrobial agents within a single, well-defined metal-organic framework. UIO-66 frameworks are investigated as carriers for the natural antimicrobial agent, Thymol, and ZnONPs offering a novel drug delivery system for antibacterial applications. Results demonstrated 132, 90, 184, and 223 nm sizes for UIO-66, ZnONPs, UIO-66 encapsulated Thymol, and UIO-66 encapsulated both Thymol and ZnONPs, respectively.
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