1,720,956 research outputs found
Effect of the Magnetic Field Generated by a New NeFeB Cover Screw on Bone Healing around Endosseous Implants: A Case Series Report from Dental Practice
No full textThis study aimed to investigate the effect of static magnetic field (SMF) generated by innovative cover screws made of NeFeB on early bone healing around dental implants. The study was carried out on humans in a private dental practice. Eight 3i implants (Biomet, Palm Beach, FL, USA) were placed in the posterior mandible at 3.6 and 3.7. The control implants were closed with a conventional screw (G1), while the test implants were closed with a Supercharged((R)) screw (G2). Both groups were compared for stability at 0, 7, 14, 21, 50, and 90 days using a resonant frequency analyzer with Ostell Mentor (Osstell AB, Gothenburg, Sweden). After 50 days, the Supercharged((R)) cover screw was removed. A significant increase in implant stability quotient (ISQ), corresponding to a lower degree of bone resorption, was observed in G2 throughout the follow-up period (p < 0.05), while an initial ISQ decrease was observed until day 21 in G1. In conclusion, the effect of SMF seems to be in the early stages of osseointegration and increases the stability of dental implants
The Effect and the Potential Use of Magnetic–Dam Barrier in Guided Bone Regeneration: A Laboratory Study
No full textGuided bone regeneration (GBR) has been shown to be an optimal technique to accelerate the bone regeneration process thanks to the action of membrane barriers that promote tissue healing through the process of osteogenesis, inducing the repopulation with osteoprogenitor cells that prevent the invasion of non-osteogenic tissue. However, current membranes, such as expanded polytetrafluoroethylene or rubber dam, have some disadvantages that could potentially reduce the effectiveness of GBR. Recently, some scaffolds with magnetic properties have been tested to promote rapid osteogenesis. The aim of this laboratory study was to evaluate the intensity of the magnetic field generated by a custom-made rubber dam magnetised with neodymium-iron-boron (Nd2F14B) (three layers of latex filled with Nd2F14B powder on the inner surface) and to understand the effects of such a membrane on cell viability. A magnetic field of 750 G, 400 G, and 900 G was generated on the surface and on the long and wide sides of 3 and 2 cm in contact with the rubber dam. At a distance of 1 mm from the magnetic dam, a magnetic field of 300 G, 150 G, and 400 G was measured on the surface and on the long and wide sides of the rubber dam, respectively. After 72 h, the MG-63 osteoblast-like line showed a slight decrease in cell proliferation (85 ± 10) compared with the unmodified dam (95 ± 6) and the cell control population. According to our findings, this magnetic cofferdam is able to generate a static magnetic field and significantly affect cell proliferation in contrast to other nonabsorbable membranes. Further laboratory studies and subsequent clinical trials are needed to evaluate the significant improvements that can be achieved by using this type of magnetic rubber dam in GBR
Restoration of Severe Bone and Soft Tissue Atrophy by Means of a Xenogenic Bone Sheet (Flex Cortical Sheet): A Case Report
Full text linkThe use of xenogenic cortical bone laminas in Guided Bone Regeneration (GBR) has been well described in the literature over the past decade. These biomaterials present a very low degree of complications due to their nature (porcine or equine collagenated bone) and the fact that when they become exposed, they simply hydrolyze without major complications. One of the problems related to the first generation of these laminas was their extreme rigidity and return elasticity, often forcing clinicians to anchor them with pins and/or screws. A new generation of bone laminas called Flex Cortical Sheet (FCS) have recently been introduced with machine-made thicknesses of 0.2, 0.5, and 0.9 mm and increased flexibility and adaptability to ridge defects. This paper has the goal of presenting a case of vertical and horizontal reconstruction performed by means of a 0.5 mm FCS and showing the workflow necessary to successfully restore a complex situation. After 8 months of healing, the GBR resulted in a horizontal and vertical augmentation of 8 mm and 8 mm, respectively. The radiographic examination at 18 months demonstrated great stability of new bone around implants
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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