An Investigation into the Accuracy of Two Currently Available Dental Impression Materials in the Construction of Cobalt-Chromium Frameworks for Removable Partial Dentures. | LitMetric
This study investigated the suitability of irreversible hydrocolloid as an impression material for cobalt-chromium framework construction. Scans of casts derived from (1) alginate and (2) addition-cured polyvinylsiloxane impressions were superposed on to a control. The differences within and between groups were compared at fixed landmarks. The investigation revealed a high degree of scan coincidence within and between groups. However, certain features, such as undercuts, resulted in a lower degree of scan coincidence. Irreversible hydrocolloid appears to be a viable alternative to addition-cured polyvinyl-siloxane as an impression material for cobalt-chromium framework construction.
Contamination of heavy metals (HMs) has caused increasing concern due to their ecological toxicities and difficulties in degradation. The transport, retention, and release of HMs in porous media are highly related to their environmental fate and risk to groundwater. Column transport experiments and numerical simulations were conducted to investigate the retention and release behaviors of Cu, Pb, Cd, and Zn in the presence and absence of kaolin under varying ionic strengths and cation types.
Background: Impression materials can harbour microorganisms from saliva and blood, posing cross-contamination risks. However, post-setting disinfection might compromise the dimensional accuracy and mechanical properties of alginates. Hence, it was the aim of this research to assess the detail reproduction, tear strength, elastic recovery, and surface quality of the gypsum model of newly developed dental alginates with inherent antimicrobial properties.
Myocardial ischemia/reperfusion injury (MIRI) is a major problem in treating heart attacks, which lead to serious heart damage and high mortality rates worldwide.
The review explores the biological mechanisms behind MIRI and highlights new developments in biomimetic nanodelivery systems, such as cell membrane-coated nanoparticles, exosomes, and nanoenzymes, as potential treatments.
The authors discuss the benefits and challenges of these innovative strategies, focusing on their effectiveness in lab studies and the hurdles to implementing them in real-world clinical settings.
Biomass pyrolysis greatly impacts climates, ecosystem dynamics, air quality, human health, global carbon and nitrogen cycle. The emissions of nitrogen-containing compounds from biomass pyrolysis highly depend on the protein nitrogen existing in biomass. However, the quantitative kinetic information, including the rate constant and apparent activation energy of individual amino acid induced by pyrolysis are still yet to be well-constrained.
Most embedding media for live and fixed samples were not designed for microscopy and have issues including long polymerization times, peak of toxicity toward the sample during the sol-gel transition, and irreversibility of this transition. Gels derived from biological sources are widely used in microscopy, but their precise composition is ill-defined and can vary between batches. Non-physiological temperatures and/or specific enzymatic solutions are often needed to revert the gel back to the sol state to allow sample recovery.
