1,720,980 research outputs found
Clinical evaluation of a self-adhering material as desensitizing agent in xerostomic patients for head and neck cancer
Full text linkXerostomia is a common clinical symptom that may suffer patients with Head and Neck Cancers during and after radiotherapy. The aim of the present thesis were therefore: 1) to review the current state of knowledge of pathology, clinical complications and radiotherapeutic patient management, 2) to evaluate the aetiology of dentine hypersensitivity in conditions of reduced salivary flow resulting in the radiation exposure, 3) to evaluate the effectiveness of the materials commonly used in the treatment of hypersensitivity, when they work in conditions of hyposalivation.Paper I is systematic review of actual management strategies for radiation-induced hypofunction and xerostomia in head and neck cancer patients. Paper II and III are based on the data of two split-mouth randomized clinical trial, where the efficacy of 4 different kinds of desensitizers has been assessed in the short and long term on patients with normal salivary flow. Paper IV is a long term evaluation based on the same experimental protocol applied on xerostomic patients.The main conclusions from this thesis are that: 1) the radiation-induced xerostomia could be considered a multifactorial disease. It could depend on the type of cancer treatment and the cumulative radiation dose to the gland tissue. A preventive approach and the correct treatment of the particular radiotherapeutic patient can help to improve the condition of xerostomia. 2) In xerostomic condition all the materials tested produced a significant reduction in the dentine sensibility. In light of the observed data, after 12-week controls there is no statistically significant difference between the desensitizers and they show a less stable behaviour compared to the normal salivation condition
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
Carious affected dentine: Its behaviour in adhesive bonding
No full textBackground Carious affected dentine (CAD) represents a very common substrate in adhesive dentistry. Despite its ability to interact with adhesive systems, the intrinsic character of CAD leads to lower bonding compared with sound dentine, regardless of the adhesive systems used. This low bonding may be more susceptible to leakage and hydrolysis of the interface by matrix metalloproteinases (MMPs). This systematic review aimed to determine current knowledge of CAD bonding, together with bond strength and MMP inhibitors' ability to prevent hybrid layer instability. Methods MEDLINE/Pubmed, Scopus and The Cochrane Library databases were electronically searched for articles published from 1 January 1960 to 31 August 2014. Two reviewers independently screened and included papers according to predefined selection criteria. Results The electronic searches identified 320 studies. After title, abstract and full-text examinations, 139 articles met the inclusion criteria. Data highlighted that a poor resin saturation of the already demineralized collagen matrix in CAD is strictly related to nanoleakage in interdiffusion and is the basis of the progressive decrease in strength with hydrolysis by MMPs. The use of mild self-etching systems seems to be the more accredited method to establish bonding in CAD. Inhibitors of MMPs may ensure better performance of CAD bonding, allowing undisturbed remineralization of the affected matrix. Conclusions CAD bonding needs further understanding and improvement, particularly to enhance the strength and durability of the hybrid layer
Recovery of the fullness of the upper lip after laminate veneer positioning: a case report
No full textEffectiveness of two self-etchings bonded clinically in caries affected dentin with homogeneous smear layer
Full text linkAim. To examine the interface of two self-etchings in carious affected dentin (CAD), under clinical conditions.
Materials and methods. Class I cavities were prepared in 21 carious premolars, refining them by the use of a fine diamond bur in order to create similar smear layer interference. The mild self-etching Clearfil SE Bond (CSE), pH = 2.0, and the strong Tyrian SPE-One Step Plus (TSO), pH = 0.5, were applied followed by a composite. Teeth were extracted and processed for TEM. The primer’s osmolarity of the self-etchings was also calculated using a microosmometer. Results. CSE hybrid layer retained smear layer residues and scattered crystallites as an effect of the mild acidity. A high presence of hydroxyapatite still protected the affected fibres within the hybrid layer. CSE primer demonstrated values of 3220 mOsm/kg. TSO interdiffusion showed strong demineralization. Resin tags were not formed in the dentinal tubules which remained obstructed by crystals. However, dissolution of peritubular dentin and porosities were observed in the intertubular regions. The osmolarity of TSO was 8200 mOsm/kg. Conclusion. Increasing the acidity and osmolarity of the self-etchings increases interference in the homogeneous reinforcement of CAD, which may predispose the hybrid layer to instability and hydrolytic degradation overtime
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
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