Objective:: The aim of the present study was to evaluate color changes and force degradation of orthodontic elastomeric ligatures in different stretching patterns during a 8-weeks period.
Methods:: Two elastomers with the minimum and two with the maximum color changing, and gray elastomers of two brands (American Orthodontics and Ortho Technology) were selected according to an opinion poll with clinicians and color changes after 4 weeks of intraoral use were evaluated. These elastomers were mounted on special jigs fabricated using a CAD-CAM technique, underwent different stretching patterns and the force was measured in 0, 24 hours, 2, 4 and 8 weeks. During in vivo part of the study, force levels of elastomers were measured after 4 weeks on a material testing machine. Data were analyzed with four-way ANOVA and Tukey post hoc tests.
Results:: All the elastomers showed color changing but the degree of color stability was significantly different. The mean force degradation was higher in 1-mm stretch groups. After 8 weeks, the average residual force of elastomers was 1.45 ± 0.18 N and the maximum force decay was seen in the elastomers that exhibited the maximum initial force.
Conclusion:: There is significant relationship between the stretching pattern and the amount of residual force of elastomers. Elastomers with higher initial forces exhibited higher percentages of force loss after 8 weeks. It seems that there is a relationship between initial color and color changing of elastomers.
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http://dx.doi.org/10.1590/2177-6709.22.2.045-054.oar | DOI Listing |
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Department of Pathology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
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January 2025
Materials Science and Engineering Program, Walker Department of Mechanical Engineering and Texas Materials Institute, The University of Texas at Austin, Austin, TX, 78712, USA.
Anode-free all solid-state batteries (AF-ASSBs) employ "empty" current collector with three active interfaces that determine electrochemical stability; lithium metal - Solid electrolyte (SE) interphase (SEI-1), lithium - current collector interface, and collector - SE interphase (SEI-2). Argyrodite LiPSCl (LPSCl) solid electrolyte (SE) displays SEI-2 containing copper sulfides, formed even at open circuit. Bilayer of 140 nm magnesium/30 nm tungsten (Mg/W-Cu) controls the three interfaces and allows for state-of-the-art electrochemical performance in half-cells and fullcells.
View Article and Find Full Text PDFJ Pharmacokinet Pharmacodyn
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Clinical Pharmacology Development Area, MSD K.K., Tokyo, Japan.
Model-informed drug development (MIDD) is an approach to improve the efficiency of drug development. To promote awareness and application of MIDD in Japan, the Data Science Expert Committee of the Drug Evaluation Committee in the Japan Pharmaceutical Manufacturers Association established a task force, which surveyed MIDD applications for approved products in Japan. This study aimed to reveal the trends and challenges in the use of MIDD by analyzing the survey results.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Pharmacy, the First Affiliated Hospital of Xi'an Jiaotong University, NO.277 Yanta West Road, Yanta District, Xi'an, 710061, Shaanxi, People's Republic of China.
4',5,6,7-tetrahydoxyisoflavone (6-hydroxygenistein, 6-OHG) is a hydroxylated derivative of genistein with excellent antioxidant activity, but whether 6-OHG can protect hypoxia-induced damage is unclear. The objective of current study was to evaluate the protective effect and underling mechanism of 6-OHG against hypoxia-induced injury via network pharmacology and cellular experiments. 6-OHG-related and hypoxia injury-related targets were screened by public databases.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!