1,721,044 research outputs found
Histological features of peri-implant bone subjected to overload
Purpose: The aim of this review has been to investigate the histological findings of bone structure surrounding implants subjected to excessive load.
Materials and methods: Clinical and pre-clinical histological studies that observed overloaded intraoral
implants were included.
Results: All included studies (n = 15) were conducted on animals. Most of them failed to find pathological
alteration in the microstructure of bone surrounding overloaded implants. Overload and infection alone
may induce bone loss, but related lesions have different and peculiar features.
Conclusions: The different histological features observed around implants subjected to overload or
to ligature-induced peri-implantitis may indicate a specific pathogenetic mechanism for overload or
infection-induced loss of osseointegration. The clinical significance of these findings should be confirmed
in human studies
Maxillary sinus floor augmentation using a nano-crystalline hydroxyapatite silica gel: Case series and 3-month preliminary histological results
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
Tissue engineering in periodontology : biological mediators for periodontal regeneration
Teeth and the periodontal tissues represent a highly specialized functional system. When periodontal disease occurs, the periodontal complex, composed by alveolar bone, root cementum, periodontal ligament, and gingiva, can be lost. Periodontal regenerative medicine aims at recovering damaged periodontal tissues and their functions by different means, including the interaction of bioactive molecules, cells, and scaffolds. The application of growth factors, in particular, into periodontal defects has shown encouraging effects, driving the wound healing toward the full, multi-tissue periodontal regeneration, in a precise temporal and spatial order. The aim of the present comprehensive review is to update the state of the art concerning tissue engineering in periodontology, focusing on biological mediators and gene therapy
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
Three-dimensional facial morphometry of attractive children and normal children in the deciduous and early mixed dentition
OBJECTIVES:
To identify possible esthetic canons in facial size and shape of Italian children. MATERIALS AND Methods: The three-dimensional coordinates of 50 facial landmarks (forehead, eyes, nose, cheeks, mouth, jaw, ears) were collected in 220 healthy reference children (4-9 years old) and in 89 "attractive" children of a similar age group selected by a commercial casting organization. Soft-tissue facial angles, distances, and volumes were computed. Comparisons were made with the Student's t-test.
RESULTS:
Attractive children had a larger face than the reference children, with a larger maxilla and forehead; overall, their faces were wider and deeper, but less vertically developed. Lips were more voluminous in attractive children, with a higher mouth. The nose was larger in attractive children than in reference children. The soft-tissue facial profile was more convex in attractive children, with a more prominent maxilla relative to the mandible.
CONCLUSIONS:
Overall, considering that in the analyzed ages body growth and dental changes are very fast and individually determined, all the measurements appeared sufficiently homogenous, and the quantitative characteristics of an "attractive" face well defined. Esthetic reference values can be used to determine optimal timing and goals in orthodontic treatment
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