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991.
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Ricardo Walter DDS MS 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2013,25(1):72-76
Recent developed flowable composite resins have been marketed for bulk filling of preparations or replacement of dentin in a single increment. The obvious attraction of these materials—quicker placement of restorations—has rapidly made them very popular despite the limited in vitro data and lack of clinical studies. This Critical Appraisal will review some of the available in vitro literature on the topic and summarize the available knowledge in this new category of restorative materials. 相似文献
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Jorge Perdigão DMD MS PhD Alessandra Reis DDS PhD Alessandro D. Loguercio DDS MS PhD 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2013,25(4):219-241
This review examines the fundamental processes responsible for the aging mechanisms involved in the degradation of resin‐bonded interfaces, as well as some potential approaches to prevent and counteract this degradation. Current research in several research centers aims at increasing the resin–dentin bond durability. The hydrophilic and acidic characteristics of current dentin adhesives have made hybrid layers highly prone to water sorption. This, in turn, causes polymer degradation and results in decreased resin–dentin bond strength over time. These unstable polymers inside the hybrid layer may result in denuded collagen fibers, which become vulnerable to mechanical and hydrolytical fatigue, as well as degradation by host‐derived proteases with collagenolytic activity. These enzymes, such as matrix metalloproteinases and cysteine cathepsins, have a crucial role in the degradation of type I collagen, the organic component of the hybrid layer. This review will also describe several methods that have been recently advocated to silent the activity of these endogenous proteases. 相似文献
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Caroline E. Veltman Saskia L.M.A. Beeres Deborah N. Kalkman Tim P. Kelder Philippine Kiès Hubert W. Vliegen Mark G. Hazekamp Victoria Delgado Lucia J.M. Kroft Ernst E. van der Wall Adriana C. Gittenberger-de Groot Arthur J.H.A. Scholte Martin J. Schalij Monique R.M. Jongbloed 《The Annals of thoracic surgery》2013
998.
Simon S. Jameson Deborah Lees Philip James Andrew Johnson Christopher Nachtsheim James L. McVie Amar Rangan Scott D. Muller Mike R. Reed 《Injury》2013
Background
The treatment of choice for intracapsular neck of femur (NOF) fractures in younger, more active patients remains unknown. Some surgeons advocate total hip replacement (THR).Aim
This study aimed to compare complications following THR and hemiarthroplasty using the Hospital Episode Statistics (HES) database in England.Method
Dislocation and revision rates were extracted for all patients with NOF fracture who underwent either cemented hemiarthroplasty or cemented THR between January 2005 and December 2008. To make a ‘like for like’ comparison all 3866 THR patients were matched to 3866 hemiarthroplasty patients (from a total of 41,343) in terms of age, sex and Charlson score.Results and conclusion
Eighteen-month dislocation was significantly higher in the THR group (2.4% vs. 0.5%, odds ratio (OR) 3.90 (2.99–5.05), p < 0.001). This difference was sustained at the 4-year stage (2.9% vs. 0.9%, OR 3.18 (1.58–6.94), p = 0.001) in a subset of patients with longer follow-up. There was no significant difference in revision rate up to 4 years (1.8% vs. 2.1%, OR 0.85 (0.46–1.55), p = 0.666). In this national analysis of matched patients short- and medium-term dislocation rates following THR were significantly higher than following cemented hemiarthroplasty, without any difference in revision rates at 4 years. The low risk of dislocation may be acceptable in order to experience the apparent functional benefits of THR. 相似文献999.
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Wright A Poon EG Wald J Feblowitz J Pang JE Schnipper JL Grant RW Gandhi TK Volk LA Bloom A Williams DH Gardner K Epstein M Nelson L Businger A Li Q Bates DW Middleton B 《Journal of general internal medicine》2012,27(1):85-92