1,720,969 research outputs found
TRATTAMENTO COMBINATO MULTIDISCIPLINARE SU GRAVE TRAUMA DENTO-ALVEOLARE A CARICO DEL SETTORE SUPERO-ANTERIORE
A new classification for crown fractures of teeth
The aim of this work is to define a classification for traumatic injuries to crowns of teeth that offers a simplified interpretation, which can be communicated easily. These data will help us to evaluate the future restorations (composite resins, crowns, porcelain veneers) according to the variable design and extension of initial crown fracture lines. For this reason we conducted research on a vast sample of subjects, who presented different traumatic lesions, in order to obtain a specific selection of these typologies of injuries. We reviewed the literature for a complete, brief classification of simple use, which could serve our cause. The traditional classifications (Andreasen, Ellis, OMS) did not satisfy us for different reasons. In fact, they only consider the initial lesion situation, never focusing on the shape of the lesion and therefore never giving suggestions for the best kind of material for restoration. On the contrary, our interest is to define the kind of more valid materials according to the variable design of crown fracture lines, to foresee the duration of these materials and the best time to substitute them. To simplify and make our research a more affordable one, we created a 4 classes classification (A-B-C-D) and 3 subclasses (b1-c1-d1). Class A: all the simple enamel lesions which involve a mesial or distal crown angle, or only the incisal edge; Class B: all the enamel-dentin lesions, which involve a mesial or distal crown angle and the incisal edge. When a pulpal exposure exists we define it a Subclass b1; Class C: all the enamel-dentin lesions, which involve the incisal edge and at least a third of the crown surface. When a pulp exposure exists we define it a Subclass c1. Class D: all the enamel-dentin lesions, which involve a mesial or distal crown angle and the incisal or palatal surface, with root cement involvement (crown-root fractures). When a pulpal exposure exists we define it a Subclass d1. This classification showed how different kinds of lesions (Class B, b1, C and c1, in our new classification) fall under the same definition (enamel-dentinal fractures) in traditional classifications (Andreasen, Ellis). However, they need a wholly different clinical approach, and the material involved in the treatment shows different behavior and duration. This new classification simplified the gathering of data and the communication among practitioners, thus confirming its importance in getting optimal diagnostic and therapeutic protocols. It also allowed us to identify the most frequent crown fractures (Class B, b1 and C, c1) that in our sample of patients (age range: 8-18) are typically treated with composite resins or original fragment reattachment technique. All these studies brought us to develop this new "easy to use" classification of dental crown lesions that helped us to gather data easily, to choose the right materials to improve the communication among practitioners including by electronic means
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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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