Statement Of Problem: High-speed sintering allows the rapid fabrication of esthetic restorations with adequate flexural strength. However, data on the fatigue behavior of high-speed sintered 4 mol% yttria-stabilized tetragonal zirconia polycrystal (4Y-TZP) are lacking.
Purpose: The purpose of this in vitro study was to examine the effect of high-speed sintering and the preshading of blanks (monochrome versus multilayer) on the fatigue behavior of 4Y-TZP ceramics.
Material And Methods: Four-point flexural strength specimens (N=405) were fabricated from high-speed sintered multilayer 4Y-TZP (Zolid DRS) processed at 1580 °C for about 20 minutes and conventionally sintered at 1450 °C for about 10 hours, multilayer 4Y-TZP (Zolid Gen-x), and monochrome 4Y-TZP (Ceramill Zolid HT+PS), the control group. The specimens were loaded under 5 different dynamic test conditions for fatigue testing (P1-P5). Three were step-stress protocols (P1: 50 N for 5000 cycles; P2: 10 N for 1000 cycles, P3: 5% for 5000 cycles), 1 was tested with a constant force of 720 N (P4), and 1 was tested for different constant load levels (P5). For analysis of P1-P3, the Kaplan-Meier test and Mantel Cox test were performed (α=.05). P4 was analyzed with the Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U tests, and P5 by creating a load-cycle diagram. A fracture analysis was performed.
Results: ZMLC showed better fatigue behavior than ZMLH (P≤.006) and ZMOC (P≤.002) in all 3 step-stress protocols (P1-P3). ZMLH showed results comparable with those for ZMOC (P≥.285). In P4 and P5, all materials showed comparable values (P=.163 for P4).
Conclusions: The multilayer technique showed a positive effect on the fatigue behavior of 4Y-TZP. In contrast, high-speed sintering negatively influenced the fatigue behavior of multilayer 4Y-TZP. The high-speed sintered material showed no deterioration compared with the conventional sintered monochrome material.
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http://dx.doi.org/10.1016/j.prosdent.2021.11.006 | DOI Listing |
Rheumatol Int
January 2025
Pharmacy, Radboudumc, Nijmegen, NL, Netherlands.
This study investigated severity, course and patterns of fatigue surrounding subcutaneous biological disease-modifying antirheumatic drug (bDMARD) injection in inflammatory rheumatic disease (IRD) patients using ecological momentary assessments and investigated self-reported adverse drug reactions (ADRs). In this prospective cohort study, IRD patients completed fatigue severity numeric rating scales (0-10) in web-based ecological momentary assessments in three waves of five days surrounding bDMARD injection. The course of fatigue was measured by the change in fatigue from pre-dosing to post-dosing scores and was classified as: worsening, improving or no clinically relevant change.
View Article and Find Full Text PDFHum Vaccin Immunother
December 2025
School of Public Health, Peking University, Beijing, China.
The attitudes of reproductive-age individuals toward COVID-19 vaccination during pregnancy are still not well understood. We aimed to explore the attitudes toward COVID-19 vaccines during pregnancy and the determinants among the Chinese reproductive-age population. An anonymous cross-sectional study was conducted in China from July 4 to August 11, 2023.
View Article and Find Full Text PDFBMJ Open Gastroenterol
December 2024
Florence Nightingale Faculty of Nursing Midwifery & Palliative Care, King's College London, London, UK
Objective: Many people with inflammatory bowel disease (IBD) experience fatigue, pain and faecal incontinence that some feel are inadequately addressed. It is unknown how many have potentially reversible medical issues underlying these symptoms.
Methods: We conducted a study testing the feasibility of a patient-reported symptom checklist and nurse-administered management algorithm ('Optimise') to manage common medical causes of IBD-related fatigue, pain and faecal incontinence.
J Clin Med
December 2024
Unitat de Suport a la Recerca Terres de l'Ebre, Fundació Institut Universitari per a la Recerca al'Atenció Primària de Salut Jordi Gol i Gurina (IDIAPJGol), 43500 Tortosa, Spain.
: Multicomponent, non-pharmacological therapies are the preferred first-line treatments for fibromyalgia (FM), but little is known about them in primary care settings. Our study assessed the effectiveness of the FIBROCARE Program in improving the quality of life, functional impact, mood, and pain of people with FM. : We conducted a pragmatic, randomized controlled trial that was not blinded for both patients and the professionals delivering the treatments in the study groups.
View Article and Find Full Text PDFSensors (Basel)
December 2024
Department of Industrial Engineering and Management, Shanghai Jiao Tong University, Shanghai 200240, China.
Taking the titanium alloy wing-body connection joint at the rear beam of a certain type of aircraft as the research object, this study analyzed the failure mechanism and verified the structural safety of the wing-body connection joint under actual flight loads. Firstly, this study verified the validity of the loading system and the measuring system in the test system through the pre-test, and the repeatability of the test was analyzed for error to ensure the accuracy of the experimental data. Then, the test piece was subjected to 400,000 random load tests of flight takeoffs and landings, 100,000 Class A load tests, and ground-air-ground load tests, and the test piece fractured under the ground-air-ground load tests.
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