Failure loads were highly influenced by base elastic modulus (t test P 0.05) was observed. The influence of cyclic rate on mean failure loads was examined (2 Hz, 10 Hz, 20 Hz) with the extremes compared statistically (t test α=.05). Testing was extended from a monolayer ceramic (leucite-filled glass) to a bilayer ceramic system (glass-infiltrated alumina). Loading piston materials (G10, aluminum, stainless steel) and piston designs were varied to eliminate Hertzian cracking and to improve performance. The influence of water during storage and loading (both monotonic and cyclic) was examined. Two bases with different elastic moduli (nickel chrome and resin-based composite) were tested for influence on failure loads. One potential dentin analog material (an epoxy filled with woven glass fibers NEMA grade G10) was evaluated for elastic modulus in blunt contact and for bond strength to resin cement as compared to hydrated dentin. Based on this analysis, an experimental technique was systematically developed and test materials were identified to recreate key aspects of clinical failure in vitro. This article first compares characteristics of traditional load-to- failure tests of ceramic crowns with the growing body of evidence regarding failure origins and stress states at failure from the examination of clinically failed crowns, finite element analysis (FEA), and data from clinical studies. The purpose of this study was to develop an in vitro failure test for ceramic single-unit prostheses that duplicates the failure mechanism and stress state observed in clinically failed prostheses. There is a need to develop and communicate an in vitro testing protocol that is clinically valid. Traditional testing of ceramic crowns creates a stress state and damage modes that differ greatly from those seen clinically. Kelly, J Robert Rungruanganunt, Patchnee Hunter, Ben Vailati, Francesca Although further clinical investigations are needed to clarify its usefulness, ghrelin is expected to become a novel therapy for cachectic patients with chronic respiratory failure.ĭevelopment of a clinically validated bulk failure test for ceramic crowns. In another study of chronic lower respiratory tract infection with cachexia, ghrelin suppressed airway inflammation by decreasing neutrophil accumulation in the airway, resulting in improvements in oxygenation and exercise tolerance. The patients in these studies gained muscle mass and weight. In a few clinical studies, including a small randomized controlled trial, ghrelin administration to cachectic patients with chronic respiratory failure improved exercise tolerance, dyspnea, and appetite. These effects of ghrelin are ideal targets for the treatment of severely wasting chronic respiratory disease. Ghrelin has various effects, including increasing food intake, attenuating sympathetic nerve activity, inhibiting inflammation, increasing cardiac output, and controlling fat utilization. Although cachectic status is an important clinical problem, there are no effective therapies for cachexia. Patients who have chronic respiratory failure with cachexia exhibit increased morbidity. Matsumoto, Nobuhiro Tsubouchi, Hironobu Imazu, Yoshifumi Arimura, Yasuji Yanagi, Shigehisa Iiboshi, Hirotoshi Nakazato, MasamitsuĬhronic respiratory failure, which is often caused by chronic obstructive pulmonary disease, chronic lower respiratory tract infection, or interstitial pneumonia, often leads to cachexia with disease progression. Everyone interested in heart failure is expected to find this compilation helpful for a deeper understanding of some of the complex issues.Ĭlinical application of ghrelin for chronic respiratory failure. The reviews include essential background information, state of the art, critical and in-depth analysis, and directions for future researches for elucidation of the unresolved issues. "Heart failure: from research to clinical practice", a collection of selected reviews, which comes out also as a book, covers essentially all important aspects of heart failure, including the pathogenesis, clinical features, biomarkers, imaging techniques, medical treatment and surgical treatments, use of pacemakers and implantable cardioverter defibrillators, and palliative care. Heart Failure: From Research to Clinical Practice.
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