1,721,011 research outputs found
Efficiency of desensitizing materials in xerostomic patients with head and neck cancer: a comparative clinical study.
Full text linkOBJECTIVES
To assess the clinical effectiveness of four desensitizing materials in patients who are xerostomic due to radiotherapy for head and neck cancer (HNC) in comparison to a healthy group with normal salivation.
METHODS AND MATERIALS
The study was conducted as a split-mouth randomized clinical trial. Forty HNC patients (group A) and 46 healthy patients (group B) suffering from dentin hypersensitivity (DH) were included. Salivary flow was determined through a scialometric test. Hypersensitivity was assessed with air stimulus and tactile stimulus. The materials used as desensitizing agents were Vertise Flow, Universal Dentin Sealant, Clearfil Protect Bond, and Flor-Opal Varnish. The response was recorded before application of the materials, immediately after, and at 1 week, 4 weeks, and 12 weeks.
RESULTS
Salivary flow rates in groups A/B were 0.15/0.53 mL/min (unstimulated) and 0.54/1.27 mL/min (stimulated), respectively. In group A, 100 hypersensitive teeth were included. Application of the desensitizing agents significantly decreased the hypersensitivity immediately and throughout the 4-week follow-up (p < 0.001). However, after the 12-week timepoint, a loss of efficacy was detected in all agents (p = 0.131). In group B, 116 hypersensitive teeth were included. The materials performed a more stable action, although a loss of effectiveness was detected at 12-week control (p = 0.297).
CONCLUSION
The efficiency of the desensitizing agents after the first application was similar in both groups. In the radiated group, this effect lasted for shorter periods than in healthy controls.
CLINICAL RELEVANCE
HNC patients with hyposalivation may be a new risk group for DH
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
Caries prevention about inorganic fluoride: a SEM investigation.
No full textAIM To investigate the adaptation of new generation fiber post compared with prefabricated glass fiber postsMATERIAL AND METHODS The experiment was performed by two experienced clinicians, the former performed endodontic therapies and the latter post restorations. The clinical crowns of twenty human extracted teeth were sectioned at the cemento-enamel junction. The canals were shaped with MTwo NiTi rotary files up to 25 .07. Root canals were filled with guttapercha points with vertical condensation technique up to 5 mm to the apex. The middle and coronal part of the canal were cleaned with GG burs 1-4, used with very light touch. Adhesion technique, using 4th generation adhesives was performed. With a random number generator, at this point the roots were divided into two groups, 10 teeth each, A and B; group A was restored with a prefabricated fiber post, group B with a new generation Ever-stick post, made of preimpregnated fibers that can be packed into the canal. Both types of posts were cemented with flowable auto-photo composite, which was allowed to set for 15 minutes.The roots were then sectioned 3 mm from the coronal end with a rotating disk, polished and photographed with a camera on a fixed mount. The images were processed with software that allowed to measure the cement thickness from fibers to dentin, with 8 measures for each specimen. The numeric data were processed with a statistical program in order to evaluate differences between groups and its significance (quantitative analysis).Qualitative analysis was performed by two experienced independent observers, the accordance of whom was evaluated with Cohen K test, that gave to each specimen a score 0-3, accordingly to the presence or absence of defects, such as voids in the material or lack of adherence to dentinal walls. Kruskal-Wallis and Mann-Whitney tests were used to identify differences in the groups.RESULTS New generation fiber posts are a valuable alternative to preformed fiber posts
Current dental adhesives system. A narrative review
No full textAdhesive dentistry is based on the development of materials which establish an effective bond with the tooth tissues. In this context, adhesive systems have attracted considerable research interest in recent years. Successful adhesive bonding depends on the chemistry of the adhesive, on appropriate clinical handling of the material as well as on the knowledge of the morphological changes caused on dental tissue by different bonding procedures. This paper outlines the status of contemporary adhesive systems, with particular emphasis on chemical characteristics and mode of interaction of the adhesives with enamel and dentinal tissues. Dental adhesives are used for several clinical applications and they can be classified based on the clinical regimen in "etch-and-rinse adhesives" and "self-etch adhesives". Other important considerations concern the different anatomical characteristics of enamel and dentine which are involved in the bonding procedures that have also implications for the technique used as well as for the quality of the bond. Etch-and-rinse adhesive systems generally perform better on enamel than self-etching systems which may be more suitable for bonding to dentine. In order to avoid a possible loss of the restoration, secondary caries or pulp damage due to bacteria penetration or due to cytotoxicity effects of eluted adhesive components, careful consideration of several factors is essential in selecting the suitable bonding procedure and adhesive system for the individual patient situation. © 2012 Bentham Science Publishers
Increases of intracanal and root surface temperatures during the obturation of canal using the E&Q master system and the system B
No full textVariations 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
Antimicrobial activity of varying concentrations of two different chemical solutions against Candida albicans biofilms
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