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Dal 2D al 3D nella diagnosi e pianificazione terapeutica dei canini mascellari inclusi = From 2D to 3D in the diagnosis and treatment planning of maxillary impacted canines
No full textObjectives The aim of this article is to present the progress in diagnosis and treatment planning of maxillary impacted canines, thanks to the introduction of three-dimensional X-ray techniques into clinical practice, such as the different types of computed tomography, and of the modern softwares which permit the digital reprocessing of DICOM data.
Materials and methods The main features of the 3D evaluation techniques are described with examples of spatial localization of impacted elements, presenting the different functions available with the modern softwares that allow 3D reconstruction.
Results The impaction of permanent upper canines is an eruption anomaly, whose prevalence is 1–3%. It is a complex problem that may lead to severe complications, and requires an accurate diagnosis associated to an individual treatment plan, both now possible thanks to modern three-dimensional reconstruction and virtual simulation.
Conclusion The many opportunities in diagnosis and treatment planning, now available thanks to the radiologic and software development, and are constantly evolving. Therefore a continuous update is necessary for the clinician to be able to offer the patients the best possible treatment
Ultrasonic versus conventional bracket removal and enamel clean-up : a preliminary study
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[Congenital neutrophil defects and periodontal diseases]
No full textAn alteration of the immune system function is one of the main factors involved in the development of periodontal disease. Polymorpho-nuclear neutrophil leukocytes (PMN) play a crucial role in the cell-mediated immune response against bacterial challenge. The mechanism of neutralization of pathogen microorganisms by PMNs involves many different steps: adhesion to capillary endothelium in the inflamed region, trans-endothelial migration, chemotaxis, phagocytosis and, ultimately, bacterial killing by oxidative and non-oxidative mechanisms. A defect in one of these steps leads to altered neutrophil function and, consequently, to a higher host susceptibility to periodontal tissue infection. The main intrinsic neutrophil diseases such as neutropenia, leukocyte adhesion deficiency (LAD-1), Chediak-Higashi syndrome, Papillon-Lefèvre syndrome, chronic granulomatous disease (CGD), are often related to severe and early-onset forms of periodontitis, as described by many evidences in the literature. Therefore PMN dysfunctions, both intrinsic and extrinsic, represent an important risk factor for periodontal disease. Studies on the basic molecular mechanisms of such dysfunctions, also in terms of genetic polymorphisms, recently allowed to identify some specific markers related to a higher susceptibility to the development of disease. Many researches have yet to be performed aiming to gain insight on the dynamics of PMN activation and interaction with other cells, in order to improve and modulate neutrophil function and to develop specific approaches for care and prevention of periodontal diseases
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
[Neutrophil physiology: role and mechanism of action in the immune response at gingival level]
No full textPolymorphonuclear neutrophil granulocytes (PMN) are considered the most important cells of the host immune response against bacterial challenge. The functional mechanism of PMN consists of different steps: tethering, rolling, primary adhesion to the vascular wall, firm adhesion to the activated endothelium in the inflamed region, trans-migration across endothelium, chemotaxis, contact with the bacterium and phagocytosis and, finally, killing of the micro-organism by releasing hydrolytic enzymes and/or by production of toxic substances such as free radicals. Each of these steps is controlled by interactions between cells and many components of the immune system or inflammatory mediators. These interactions generate specific signals, important for cell regulation. Recent technological advances in molecular biology and immunobiology allowed to disclose the precise role of various molecules involved in the immune response, that regulate PMN function; conversely, more factors have been identified, whose role is still unknown. In the process of adhesion, for example, many classes of molecules are involved (selectins, integrins, ICAMs). The interaction of these molecules (es.: selectin) with their ligands (non completely discovered) is characteristic of specific stages, but may also regulate the successive steps (integrin activation). In periodontal infections, PMNs of gingival tissue migrate towards bacteria of dental plaque along a chemotactic gradient of specific factors (ICAM-1, IL-8) produced by cells of the junctional epithelium. Such gradient is essential to drive PMNs through molecular traffic. Among the mechanisms used by PMNs to kill bacteria, the importance of nitric oxide (NO) production has been recently pointed out
Variations on the Author
Get PDF“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
Get PDFWe 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
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