Purpose: The effect of annealing and firing cycle on the adaptation of cobalt-chromium (CoCr) restorations fabricated by additive manufacturing has been poorly documented. This study compared the marginal and internal fit of CoCr three-unit fixed dental prostheses before and after firing cycles.
Material And Methods: The first right maxillary premolar (MP) and molar (MM) on a typodont model, were prepared with a circumferential 1.2 mm chamfer, 2 mm occlusal reduction, and total taper of 8 degrees, to receive 3-unit fixed dental prostheses (FDP). After the framework design, 20 framework specimens were fabricated using CoCr metal powder by selective laser melting. The replica technique was used for marginal and internal fit measurements in mesiodistal and buccolingual planes. The specimens were submitted to an annealing process, and to ceramic firing protocol. Measurements were repeated after each firing cycle. The data were compared by using Levene test, t-test, and analysis of variance (ANOVA) (α = 0.05).
Results: A significant difference was found in the total intaglio surface discrepancy between the 3 treatments. The annealing treatment induced a statistical difference in the discrepancy value compared to the as printed state (p = 0.028). A significant difference was detected between the initial manufacturing phase and the ceramic layering firing cycle (p = 0.003).
Conclusions: Firing cycles induced an alteration of the frameworks adaptation.
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http://dx.doi.org/10.1111/jopr.13506 | DOI Listing |
Alzheimers Dement
December 2024
University of Michigan School of Public Health, Ann Arbor, MI, USA.
Background: Numerous social factors, including socioeconomic status, education, and healthcare access, influence health outcomes in older adults. Despite the potential clinical utility of assessing social vulnerability, it is not routinely evaluated in clinical assessments of older adults. This study aims to investigate the association between cognitive decline and a comprehensive social vulnerability index, defined as an index comprising many social factors such as income, education, and housing tenure.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
STEM Neurology & Neuropsychological0 Research Group Egypt (SNRGE), Port Said, Port Said, Egypt.
Background: The circadian rhythm controls physiological functions across by responding to environmental light cues. fluctuations in this rhythm, such as those induced by irregular work schedules, have been associated with adverse health outcomes, this study aims to assess the increased likelihood risk of developing Alzheimer's dementia for workers with irregular work schedules.
Methods: Exploring and referencing studies on Alzheimer disease (AD) which had proved an undeniable relationship between dopamine levels with AD onset, this study showcases the relationship of dopamine levels and circadian rhythm and its effect indirectly on Alzheimer as a predisposing factor of AD.
Eur J Cancer
January 2025
Medical Oncology Department, Hospital 12 de Octubre, Madrid, Spain; Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12), Madrid, Spain; SOLTI Cancer Research Group, Barcelona, Spain. Electronic address:
Introduction: The prognostic value of PAM50 intrinsic subtypes (IS), cell cycle, and immune-related gene expression in HR+ /HER2- advanced breast cancer (BC) treated with CDK4/6 inhibitors (CDK4/6i) and endocrine therapy (ET) in a first-line metastatic setting is unclear. This study evaluates these biomarkers in metastatic biopsies from patients diagnosed with HR+ /HER2- advanced BC.
Methods: CDK-PREDICT study is a multicentric, ambispective observational cohort study conducted in six Spanish hospitals.
J Prosthodont
January 2025
Department of Dentistry, Federal University of Rio Grande do Norte (UFRN), Lagoa Nova, Natal, Brazil.
Purpose: To assess the impact of staining and multiple firings on the mechanical, optical, and surface characteristics of zirconia-containing lithium silicate ceramics (ZLS).
Materials And Methods: Ninety ZLS discs (Suprinity, VITA Zahnfabrick) were divided according to the "Number of firings" protocol: Ctr-control, no characterization; SC-single firing cycle (for characterization, crystallization and staining simultaneously); and DC-double firing cycle (crystallization firing cycle was performed separately from the staining firing). Extrinsic pigmentation was performed to replicate the characterization of a monolithic restoration.
Microorganisms
November 2024
School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan 430078, China.
Iron, Earth's most abundant redox-active metal, undergoes both abiotic and microbial redox reactions that regulate the formation, transformation, and dissolution of iron minerals. The electron transfer between ferrous iron (Fe(II)) and ferric iron (Fe(III)) is critical for mineral dynamics, pollutant remediation, and global biogeochemical cycling. Bacteria play a significant role, especially in anaerobic Fe(II) oxidation, contributing to Fe(III) mineral formation in oxygen-depleted environments.
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