This study analyzed the effectiveness of root canal filling removal in lower molars performed by beginner operators using optical microscopy. A total of 55 mandibular first and second molars with mesial roots exhibiting an average curvature of 10-20° were selected based on preoperative radiographs. Instrumentation was done with ProTaper Gold (Dentsply Sirona) up to F2 (25/.
View Article and Find Full Text PDFOral health is situated within the framework of the global health agenda, addressing facets pertaining to well-being and quality of life. The research is based on the need to address variables at the community level to improve schoolchildren's oral health and promote healthy behaviors and aims to carry out an in-depth analysis from the perspective of the factors that influence children's oral health. Step 1, designed by the World Health Organization, was utilized.
View Article and Find Full Text PDFThis research analyzes the dental hygiene habits of schoolchildren from parents' perspectives, using the STEPS approach recommended by the World Health Organization. The key points of oral health care in children include the role of the family in encouraging and maintaining proper oral hygiene practices. This study aimed to assess the oral hygiene practices of schoolchildren with on-site dentists in Romania.
View Article and Find Full Text PDFA great burden is put on healthcare systems by dental caries and understanding patients’ treatment needs is of utmost importance. The aim of this pre−post study was to assess dental anxiety and the psychological stress induced by two different types of dental treatment (prophylaxis and cavity preparation), by combining psychometric evaluations with salivary biomarkers, in a group of 28 schoolchildren presenting in a university clinic. Pre- and post-treatment unstimulated whole saliva was collected and levels of cortisol, alpha-amylase (sAA) and total protein content were measured.
View Article and Find Full Text PDFSalivary biomolecules are considered important modulators of the oral microflora, with a potential subsequent impact on dental health. The present study aimed to investigate the relationship between salivary enzymatic activity and carious experience in children. The carious experience of a sample of 22 school children was evaluated by calculating dmf/DMF indices, following WHO recommendations.
View Article and Find Full Text PDFIntroduction: Dental agenesis (DA), brings together the anodontia, oligodontia, hypodontia, characterized by a deficit in the development of a variable number of teeth. The objectives of the study were to illustrate the phenotypic variability of non-syndromic DA, to identify cases of DA with hereditary genetic transmission, and establish the mode of DA genetic pattern in these cases, together with the determination of DA prevalence in the population group study.
Patients, Materials And Methods: The cross-sectional observational study was performed on a mixed population group, consisting of 861 Caucasian patients, between January 2018-December 2019.
This review article discusses the current and future possibilities for the application of in situ transmission electron microscopy to reveal synthesis pathways and functional mechanisms in complex and nanoscale materials. The findings of a group of scientists, representing academia, government labs and private sector entities (predominantly commercial vendors) during a workshop, held at the Center for Nanoscale Science and Technology- National Institute of Science and Technology (CNST-NIST), are discussed. We provide a comprehensive review of the scientific needs and future instrument and technique developments required to meet them.
View Article and Find Full Text PDFWe demonstrate quantitative core-loss electron energy-loss spectroscopy of iron oxide nanoparticles and imaging resolution of Ag nanoparticles in liquid down to 0.24 nm, in both transmission and scanning transmission modes, in a novel, monolithic liquid cell developed for the transmission electron microscope (TEM). At typical SiN membrane thicknesses of 50 nm the liquid-layer thickness has a maximum change of only 30 nm for the entire TEM viewing area of 200×200 µm.
View Article and Find Full Text PDFMetal nanoparticles are commonly supported on metal oxides, but their utility as catalysts is limited by coarsening at high temperatures. Rhodium oxide and rhodium metal nanoparticles on niobate and tantalate supports are anomalously stable. To understand this, the nanoparticle-support interaction was studied by isothermal titration calorimetry (ITC), environmental transmission electron microscopy (ETEM), and synchrotron X-ray absorption and scattering techniques.
View Article and Find Full Text PDFRechargeable, all-solid-state Li ion batteries (LIBs) with high specific capacity and small footprint are highly desirable to power an emerging class of miniature, autonomous microsystems that operate without a hardwire for power or communications. A variety of three-dimensional (3D) LIB architectures that maximize areal energy density has been proposed to address this need. The success of all of these designs depends on an ultrathin, conformal electrolyte layer to electrically isolate the anode and cathode while allowing Li ions to pass through.
View Article and Find Full Text PDFMagnetic nanostructures and thin films display novel magnetization reversal behavior as a function of size and shape, which makes them appropriate for a range of technological applications. The spatial resolution of in situ transmission electron microscopy techniques such as Lorentz TEM (LTEM) and off-axis electron holography are well suited to analysis of the magnetic domain structure and magnetization behavior of these magnetic nanostructures and thin films. In this article the various techniques that are applicable are described, including the qualitative LTEM imaging modes and the differential phase contrast technique.
View Article and Find Full Text PDFMonodispersed FePt nanoparticles are synthesized by reduction of iron(II) acetylacetonate and platinum(II) acetylacetonate with 1,2-hexadecanediol as the reducing reagent in the polyol process. As-prepared FePt nanoparticles are chemically disordered with fcc phase. Transmission electron microscopy (TEM) images show a self-assembled particle array with an average particle size of 3 nm and a standard deviation about 10%.
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