Dissertations / Theses: 'Post-Bond'

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Wagner, Andrew. "Municipal bond market efficiency post the implementation of RTRS transparency regulations /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18675.pdf.

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Kupselaitis, Kurt. "Evaluation of Strand to Grout Bond in Post-Tensioned Tendons with Corrosion Inhibiting Penetrants." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7834.

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Post tensioning bridges is an efficient way of construction where segments of a bridge are strung together using small diameter high strength strands. The steel strands are passed through internal and/or external ducts within the concrete segments, jacked to high levels of stress, anchored using steel wedges, and then filled with a corrosion inhibiting filler. A cementitious material called grout has been widely used for over 50 years as this filler. The Federal Highway Administration design and construction manual provides recommendations in the properly filling techniques to ensure the tendons are full of grout. Despite the level of detail the manual provides, several Florida bridges that used this construction technique have seen severe corrosion related failures due to poor grout quality. Oil based products have been developed for the express purpose of reducing the corrosion rate in previously grouted tendons. Utilizing the interstitial spaces in the steel strands, low viscosity fluid is pumped through the strand which can also penetrate the surrounding grout and fill unintentional voids. However, by doing so, there is the concern that the bond strength could be compromised and increase the risk of failure. This study presents the findings of small scale grouted mono-strand tendons which determined the bond effects of defective grout, evaluated the injection capabilities of various penetrants, and determined whether or not the penetrant adversely affects bond after impregnation. No appreciable variation in bond was found.

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Iacono, Carole-Anne. "Le sujet de la folie contemporaine : de la croyance mythique au sacre de l'hyper techni-cité dans le discours post-traditionnel." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR2027/document.

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Ce travail se propose d’interroger le sujet pris sous le joug des discours de la post-modernité, à partir de ce que nous repérons comme la désacralisation de la croyance mythique. Ce remodelage symbolique fait basculer le lien social vers une société de la technique, une techni-cité, gouvernée par de nouvelles puissances économiques GAFAtisantes. Le sujet contemporain s’assujetti ainsi aux injonctions a-surmoïques d’un Père 2.0 qui le pousse toujours davantage dans la dégringolade subjective d’une jouissance absolue et massifère. Cette nouvelle organisation sociale fait alors éclore de nouvelles représentations de la folie. C’est ce qui nous pousse à réinterroger cette notion qui éclaire l’ensemble de notre propos. La clinique contemporaine témoigne de quelques formes de résistances du sujet. Celui-ci, ayant besoin de renouveler son rapport à l’Autre, se tourne vers de nouvelles formes de spiritualités qu’il prélève dans d’autres cultures. Il espère à partir de la mise en pratiques de ces traditions pouvoir extraire un savoir sur sa propre condition. Ce faisant, il technicise ces croyances importées qui aussitôt arrachées à leur socle symbolique virent à l’imaginaire et s’assignent à la logique capitaliste. Les nouvelles pratiques qui en émergent relèvent alors d’une post-traditionnalité qui offre un compromis au sujet cherchant à se renouveler subjectivement.La post-modernité ne connaissant aucune frontière, nous mettrons ces questions en jeu dans d’autres sociétés, notamment en Amazonie, au Sénégal et au Vanuatu. Nous constaterons que la folie demeure intimement liée au désordre social et que la contamination du discours économico-techno-scientifique contemporains produit des effets au-delà de la culture occidentale
This research proposes to question the subject taken under the yoke of the discourses of the post-modernity, from what we see as the desecration of mythic belief. This symbolic remodeling shifts the social link towards a society of technology, a “techni-cité”, governed by new « GAFA » economic powers. The contemporary subject is thus subject to the a-parametric injunctions of a Father 2.0 which pushes him ever further into the subjective tumble of an absolute and massive enjoyment and « massifere ». This new social organization then gives rise to new representations of madness. This is what drives us to re-examine this notion that sheds light on our whole subject. This new social organization then gives rise to new representations of madness. This is what drives us to re-examine this notion that sheds light on our whole subject.The contemporary clinic shows some forms of resistance of the subject. The latter, needing to renew his relationship with the Other, turns to new forms of spirituality that he takes from other cultures .He hopes from the putting into practice of these traditions to be able to extract knowledge about his own condition. In doing so he technicizes these imported beliefs, which are immediately torn from their symbolic base, turn to the imaginary and take up capitalist logic. The new practices that emerge from it are part of a post-traditionalism that offers a compromise to the subject that seeks to renew itself subjectively.Since post-modernity knows no boundaries, we will put these issues at stake in other societies, particularly in the Amazon, Senegal and Vanuatu. We will find that madness is closely linked to social disorder and that the contamination of contemporary economic-techno-scientific discourses produces effects beyond occidental culture

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Markus, Lundholm. "Factors affecting liquidity in the Nordic corporate bond market : A study on MiFiR required post trade transactions." Thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-180532.

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The Nordic corporate bond market is a market growing in significance of the financial landscape, but is rather sparsely investigated due to its low transparency characteristics. Utilizing the new EU legislative framework MiFiR, this study implements a quantitative liquidity measure on transactions reported as required by MiFiR. In the study 2817 Nordic corporate bond transactions were collected and analyzed on both a bond and market level, in a liquidity context. The bond characteristics coupon size, trade frequency, trade volume, low credit rate and price were suggested to be related to bond liquidity. Market liquidity was implied to be closely dependent to the VIX-index and the volatility of the OMXS30-index. Furthermore, the suitability of today’s bond market valuation method was questioned.
Den Nordiska marknaden för företagsobliationer är en marknad vars betydelse för det finansiella universet ökar, dock är den förhållandevis dåligt undersökt på grund av dess dåliga insyn. Denna studie använde sig av den nya EU-regleringen MiFiR och dess krav på transaktionsrapportering för att kvantitativt mäta likviditeten i marknaden. I studien har 2817 transaktioner i Nordiska företagsobligationer samlats in och analyserats i en likviditetskontext på både obliagtions- och marknadsnivå. Obligationsattributen kupongstorlek, handelsfrekvens, handelsvolym, lågt kreditbetyg och pris påstogs vara relaterade till obligationens likviditet. Likviditeten på företagsobligationsmarknaden ansågs vara starkt beroende av VIX-indexet och volatiliteten för OMXS30-indexet. Vidare diskuterades också tillförlitligheten av tillvägagångssättet som används idag för att värdera obligationerna.

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Zhang, Burong. "Experimental and theoretical investigations of a new bond-type anchorage system for post-tensioning applications with FRP tendons." Thèse, Université de Sherbrooke, 2001. http://savoirs.usherbrooke.ca/handle/11143/1732.

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Fiber reinforced polymer (FRP) composite rods appear very promising to be used as an alternative to steel in prestressed concrete structures and ground anchors, especially for applications exposed to corrosive environments. The objectives of this study are to investigate the bond behavior of FRP rods to grout filled in steel tubes and hence to develop a competent bond-type anchorage system for post-tensioning applications with FRP multirod tendons. The research program includes pullout tests of grouted FRP rods and proving tests of the developed anchorage system for post-tensioning applications. Modeling the bond behavior and predicting the load bearing capacity of bond-type anchorage systems are also involved. Numerous (over 50) pullout tests were conducted and discussed to better understand bond mechanisms and the influence of type of fiber, outer surface, and other significant parameters (i.e., confining stiffness, grout type and curing condition) on bond performance. Modeling of bond-slip behavior of grouted FRP rods is examined to assess its adequacy to reproduce the experimental bond behavior. Based on the monitoring results of strain distribution along the bonded length, the working mechanism of bond-type anchorages for FRP tendons is discussed. A conceptual model for calculating the bond stress at the tendon-grout interface and the tensile capacity of bond-type anchorages for FRP tendons is established. A new bond-type anchorage system has been developed for post-tensioning applications with FRP tendons. Evaluations of the developed anchorage system have been conducted in anchorage models with CFRP mono- and 9- rod tendons under tensile and sustained loading conditions. Furthermore, the developed anchorage system has also been used as an anchor head for post-tensioning of a full-scale FRP anchor model. Primary test results have indicated that the developed bond-type anchorage performs well for post-tensioning applications with FRP tendons. Conclusions and recommendations are made on the design of bond-type anchorages and post-tensioning applications of FRP tendons. Six related papers have been published in referred journals or international conferences, including two papers in the ASCE Journal of Composites for Construction , one in Construction and Building Materials (UK), one in the Canadian Journal of Civil Engineering , and two in the international conferences.

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Polo, Luz. "Caractérisation et optimisation de la performance des cartouches d'ancrage AMBEX sous chargement soutenu." Mémoire, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/10138.

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Les systèmes d’ancrages adhésifs sont utilisés dans plusieurs applications en génie civil, notamment en réhabilitation et réparation des ouvrages d’infrastructure tels que des dalles de ponts, chaussées, tunnels, barrages, murs, poteaux, ainsi que dans certains travaux d’exploration géologique et minière. Un système d’ancrage adhésif comprend trois composants : l’élément d’ancrage : une barre d’armature ou une tige filetée ; le matériau adhésif : polymérique, cimentaire ou hybride ; et le substrat : en béton ou en maçonnerie. Les charges imposées sur les barres d’ancrage sont transmises au substrat par adhérence chimique (réactions) et liaison mécanique (interlock) entre les composants mentionnés. Le modèle de design d’adhérence uniforme établit que la performance structurale d’un système d’ancrage adhésif est déterminée par la contrainte de l’adhérence (τ), développée sur toute la surface de contact, entre les composants à l’intérieur du trou d’ancrage. Ce projet, en partenariat avec l’entreprise AMBEX, étudie et évalue la performance des systèmes d’ancrage avec adhésifs en matériau cimentaire, par rapport au comportement sous chargement continu. Pour ce faire, on a ancré des barres d’armature dans un substrat en béton conventionnel. Les deux adhésifs étudiés sont les cartouches d’ancrage AAC et ARC. On a tenu compte des paramètres géométriques et d’installation en assurant la rupture de l’adhérence lors des essais d’arrachement. On a évalué deux conditions en service: température ambiante (21ºC) et élevée (43ºC). On a effectué des essais statiques de traction et des essais sous chargement soutenu. Les résultats sont présentés dans des graphiques « chargedéplacement-temps », afin d’établir des prédictions futures de comportement. Le projet montre les avantages des ancrages adhésifs en matériau cimentaire, tels que le taux de fluage très faible sous chargement soutenu, et quelques limitations aussi, comme la variabilité des résultats à l’arrachement pour les ancrages avec la cartouche AAC.
Abstract : Adhesive anchoring systems are used in many civil engineering applications, including rehabilitation and repair of infrastructure such as bridge decks, roadways, tunnels, dams, walls, columns, and in some geological explorations and mining. An adhesive anchoring system consists of three components: the anchor: a reinforcing bar or a threaded rod; the adhesive material: polymeric, cementitious or hybrid; and a substrate of concrete or masonry. The loads applied on the anchor rods are transmitted by a chemical adhesion to the substrate (reactions) and mechanical interlock between the components mentioned. The design pattern of uniform adhesion establishes that the structural performance of an adhesive anchoring system is determined by the bond strength (τ) developed across the contact surface, between the components within the anchor hole. This project, in partnership with AMBEX, investigates and assesses the performance of an anchoring system, with an adhesive of cementitious material, related to the creep behaviour. To achieve this, steel rebars were anchored in a conventional concrete substrate. Two adhesives were evaluated: AAC and ARC cartridges. Geometrical and installation parameters were taken into account, to ensure bond failure during pullout tests. Two service conditions were studied: room temperature (21ºC) and high temperature (43ºC). Static tensile tests and creep tests were performed. The results are presented in graphs “load-displacement-time”, in order to make predictions of future behavior. The project shows the advantages of adhesive anchors made of cementitious material, as a feeble creep rate at sustained load, and also some limitations, as the variability of tension test results for anchors tested with AAC cartridge.

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Cordeiro, Nara Pereira d'Abreu. "Resistencia ao cisalhamento por extrusão - "push out" - de pinos de fibra de vidro a dentina intra-radicular." [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288200.

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Orientadores: Mario Fernando de Goes, Luis Roberto Marcondes Martins
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-03T15:59:52Z (GMT). No. of bitstreams: 1 Cordeiro_NaraPereirad'Abreu_D.pdf: 3561839 bytes, checksum: 125cbc91719d6a902ce59502debf7873 (MD5) Previous issue date: 2003
Resumo: o objetivo deste estudo foi avaliar a resistência ao cisalhamento por extrusão (push out) entre a dentina intra-radicular e pinos de fibra de vidro nas regiões cervical, média e apical de raízes utilizando dois sistemas de cimentação adesiva. Foram selecionados vinte pré-molares inferiores unirradiculares recém extraídos por motivos ortodônticos, hígidos e livres de trincas. As coroas dos dentes foram removidas na altura da junção cemento esmalte. As polpas dentais foram removidas através de limas endodônticas e os condutos radiculares foram preparados com brocas de largo nO 5, com 8,Omm de penetração. As raízes foram divididas em dois grupos de 10: Grupo 1- pino fixados com o sistema adesivo autocondicionante ED Primer e cimento resinoso Panavia F; Grupo 2- pinos fixados com o sistema adesivo de frasco único Single Bond e cimento resinoso Rely X. Após a fixação dos pinos, as raízes foram mantidas em estufa a 37°C, por 24 h. A porção mais apical das raízes foi seccionada até a altura em que a raiz apresentasse 8,Omm de comprimento. Em seguida, as raízes foram seccionadas transversalmente e 3 discos de 2,7mm de altura foram obtidas e classificadas segundo a região cervical, média e apical do pino. O ensaio de resistência de união por extrusão foi realizado em máquina de ensaio universal Instron 4411 onde uma haste metálica com ponta ativa de 1,Omm de diâmetro produziu a carga para efetuar o deslocamento do pino do conduto radicular. Os valores médios de resistência de união por extrusão não apresentaram diferenças estatísticas significantes no terço cervical da raiz entre os dois materiais de fixação avaliados. Nas regiões média e apical do conduto, os valores de resistência de união apresentados pelo Sing/e Bond + Re/y X foram superiores e estatisticamente diferentes em relação aos valores apresentados pelo sistema ED Primer + Panavia F (p< 0,05). Para os dois materiais em estudo, não houve diferença estatística quando comparadas as regiões média e cervical do pino, porém apresentaram diferença estatística em relação à região apical (p< 0,05). Após o ensaio de cisalhamento por extrusão, os espécimes foram seccionados no sentido longitudinal para análise em microscopia eletrônica de varredura. A zona de interdifusão adesivo/dentina produzida pelo adesivo de frasco único Sing/e Bond apresentou-se mais espessa do que a zona de interdifusão apresentada pelo adesivo autocondicionante ED Primer. Houve áreas desmineralizadas com presença de túbulos dentinários abertos porém parcialmente preenchidos pela resina em ambos os grupos. Também foram observadas bolhas que variaram de tamanho e forma na camada de cimento junto à área da interface de união e mais constantes no terço apical das raízes. Palavras-chave: pino de fibra de vidro; cimento resinoso; sistema adesivo; resistência de união; "push out
Abstract: The purpose of this study was to evaluate the bond strength between fiber posts cemented in root dentin considering different depths of the roots (cervical, median and apical) and two luting materiais, through push out tests and to examine the integration among these components through scanning electron microscopy. Twenty sound bicuspids, tree trom cracks, extracted for orthodontic reasons, were selected. The crowns were removed at the cement enamel junction. The pulps were removed with endodontic reamers and the first 8,Omm of the canais were shaped with number 5 largo burs. The roots were divided into two groups of 10 each. The roots trom group 1 received fiber posts cemented with the self etching primer ED Primer and the composite resin Panavia F., while the roots of Group 2 received fiber posts cemented with the one bottle adhesive Single Bond and the composite resin Rely X. After the posts cementation, the roots were kept in humidity at 3-,0 C for 24 hours. The most apical part of the roots were sectioned until they were 8.0mm long. After that, the roots were sectioned transversally and three 2.7mm thick sections were obtained: cervical, median and apical. The push out test that evaluated bond strength between luting material and root dentin was carried out on an Instron (4411) testing machine. The specimens were positioned on a steel support platform with the post centered over a 2.0mm hole in the platform. A steel probe 1.0mm in diameter was centered over the post and used to apply force to the test specimens. Data from the push out test revealed no statistically significant differences at the cervical portion of the root between the two cementation systems tested. At the median and apical portion of the root, the bond strength values presented by the Sing/e Bond and Re/y X were superior and statistically different from those presented by ED Primer and Panavia F (PDoutorado
Dentística
Doutor em Clínica Odontológica

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Mahindre, Prajakta Prakash. "Micro-push-out bond strength and the modes of failure for a fiber-reinforced resin-post system cemented using four adhesive lutingcements." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43224052.

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Quintero, Mayra Zamboni. "Avaliação in vitro da resistência de união à tração de três tipos de pinos de fibra cimentados a raízes bovinas com diferentes cimentos resinosos." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/23/23134/tde-15012013-164556/.

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Este estudo teve como objetivo avaliar, através de testes de tração, a resistência de união de pinos pré-fabricados, com diferentes graus de translucidez, à dentina bovina, utilizando três tipos de cimentos resinosos. Noventa incisivos bovinos tiveram suas coroas anatômicas separadas das raízes através de uma secção perpendicular ao longo eixo dos dentes na junção amelocementária, de modo que as raízes apresentassem 14 mm de comprimento. Os condutos radiculares foram tratados endodonticamente e os espécimes, mantidos em água destilada a 37°C por 7 dias. Após esse período, foi realizada a desobturação de 7 mm de profundidade de cada conduto para a cimentação dos três tipos de pino: Exacto (Angelus), translúcido; Reforpost fibra de vidro (Angelus), branco; e Reforpost fibra de carbono (Angelus), negro e opaco. Três tipos de cimentos resinosos foram utilizados de acordo com as recomendações dos fabricantes: o cimento dual auto-adesivo Rely X U100 (3M ESPE); o cimento dual Rely X ARC (3M ESPE), associado ao sistema adesivo autopolimerizável Scotchbond Multi-Uso Plus (3M ESPE); e o cimento de ação exclusivamente química Cement Post (Angelus), associado ao sistema adesivo Fusion Duralink (Angelus), constituindo 9 grupos experimentais (n=10). Após a armazenagem dos corpos de prova em água destilada a 37º C por 7 dias, foi realizado o teste de tração no aparelho de ensaio mecânico da marca Kratos Equipamentos, a uma velocidade de 0,5mm/min até a ruptura dos mesmos. Para determinar a tensão de tração, foi calculada a área de adesão de cada espécime. Os dados foram analisados estatisticamente através da Análise de Variância e do teste de Kruskal-Wallis, com grau de significância de 5%. Os espécimes foram examinados através de um microscópio óptico Olympus (Tokyo, Japão), com 20x de aumento, para avaliação do modo de fratura. Em relação às variáveis estudadas, verificou-se que: o pino Exacto, com maior translucidez e maior conicidade, apresentou valores de resistência à tração significativamente inferiores do que os pinos Reforpost Fibra de Vidro e Reforpost Fibra de Carbono, quando utilizado o cimento Rely X ARC; o cimento dual auto-adesivo Rely X U100 apresentou menores valores de resistência à tração do que cimento dual Rely X ARC quando utilizados os pinos Reforpost Fibra de Vidro e Reforpost Fibra de Carbono; e o cimento de polimerização química Cement Post apresentou menores valores de resistência à tração em relação aos cimentos duais, independente do tipo de pino testado. Quanto à análise microscópica, observou-se que os cimentos resinosos aderiram mais aos pinos do que à dentina radicular. Portanto, a translucidez dos pinos não contribuiu para aumentar a resistência à tração dos cimentos resinosos duais em nenhum dos grupos testados.
This study aimed to evaluate, through tensile test, the bond strength of prefabricated posts with different degrees of translucency, using three types of resin cements. Ninety bovine incisors were selected and sectioned at the cemento-enamel junction. The root canals were endodontically treated and the specimens were stored in distilled water at 37°C for 7 days. After this period, a 7-mm-deep post space was prepared for the cementation of three types of posts: Exacto (Angelus), translucent; Fiberglass Reforpost (Angelus), white; and Carbon Fiber Reforpost (Angelus), black and opaque. Three types of resin cements were used according to manufacturers\' instructions: the self-adhesive dual cement Rely X U100 (3M ESPE); the dual cement Rely X ARC (3M ESPE), associated with autopolymerized adhesive system Scotchbond Multi-Uso Plus (3M ESPE), and the self-cured cement Cement Post (Angelus), associated with the autopolymerized adhesive system Fusion Duralink (Angelus), constituting nine experimental groups (n = 10). After the storage of the specimens in distilled water at 37°C for 7 days, the tensile test was performed with a universal test machine at a crosshead speed of 0.5 mm/min. To determine the bond strength, the bonding area of each specimen was calculated. The data were statistically analyzed by ANOVA followed by Kruskal-Wallis test, with a significance level of 5%. The dislodged posts were examined microscopically (Olympus; Tokyo, Japan) at x20 magnification to determine the type of failure. Regarding the variables studied, it was found that: the Exacto post, more translucent and tapered, had significantly lower tensile bond strength than Fiberglass Reforpost and Carbon Fiber Reforpost when used the dual cement Rely X ARC; the dual self-adhesive cement Rely X U100 showed lower tensile bond strength than the dual cement Rely X ARC, when used Fiberglass Reforpost and Carbon Fiber Reforpost; regardless of the type of post tested, the self-cured cement Cement Post had lower tensile strength compared to dual cements. It was observed microscopically that resin cements adhered more to the posts than to the root dentin. Therefore, the translucency of the posts had not contributed to increase the tensile strength of dual-curing resin cements in all groups tested.

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Almulhim, Khalid. "Effect of resin cement, aging process and root level on the bond strength of the resin-fiber posts." Thesis, NSUWorks, 2014. https://nsuworks.nova.edu/hpd_cdm_stuetd/16.

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Background . Little is known about the long-term clinical bonding effectiveness of the Fiber-reinforced composite (FRC) posts cemented with self-etch adhesive systems. Bond stability and longevity of the cemented post are adversely affected by physical and chemical factors over time, such as expansion and contraction stresses caused by thermal changes and occlusal load. This clinical condition can be simulated in vitro by thermocyclic loading; and bonding effectiveness can be evaluated by applying the micropush out test. Therefore, more in vitro studies are needed to evaluate the bond strength of the fiber posts cemented with different resin cement systems after simulating the artificial aging induced by thermocycling. The aim of this study was to compare the microtensile bond strength of two different resin cement systems (total etch, and self-etch resin cement system) used for cementation of fiber reinforced composite posts in three different aging periods using thermocycling. Methods . Following IRB approval, sixty freshly extracted bicuspid single rooted natural teeth were endodontically treated, and the post-spaces were prepared to receive a fiber-post cemented with either a total etch resin cement (Rely-X Ultimate) or with a self-etch resin cement (Rely-X Unicem). No thermocycling, 20,000 and 40,000 cycles was used to age the specimens. Teeth were randomly allocated into six different groups: G1 - Control: Rely-X Ultimate cement with no thermocycling. G2: Rely-X Ultimate cement with 20,000 thermocycling. G3: Rely-X Ultimate cement with 40,000 thermocycling. G4: Rely-X Unicem cement. G5: Rely-X Unicem cement. G6: Rely-X Unicem cement. Microtensile bond strength determined using a micropush out test on a universal testing machine (MTS). Additionally, the failure mode of each specimen was observed under a stereomicroscope (Olympus) at 40x magnification. Finally, one representative sample was randomly selected from each of the five failure modes for scanning electron microscope (SEM) examination of the surface morphology in order to obtain SEM images of the failure patterns at 29-70x magnifications. Statistical analysis: Nested general linear and generalized linear model was created to look for statistical significance. Level of significance was set at P < 0.05. Results . No significant differences were found on the bond strength between the two types of resin cement systems (total etch and self-etch). Regarding the thermocycling effect, the bond strengths of the group of 40,000 cycles was significantly lower than the 20,000 cycle group. In addition, the bond strengths of the specimens collected from the coronal third of the root were significantly lower than the specimens from the apical third. A Fisher's Exact test was applied to evaluate the failure mode differences, and showed statistically significant differences between the groups. Conclusions . The bond strength to the root canal dentin did not vary with the type of resin cement systems (total-etch vs self-etch). The microtensile bond strength values of FRC posts were significantly affected by increasing the thermocycling, and were significantly different among the different longitudinal levels of the root canal.

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Matsumiya, Nozomi. "Optimization of disulfide mapping using mass spectrometry." Thesis, Kansas State University, 2009. http://hdl.handle.net/2097/1358.

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Master of Science
Biochemistry
John Tomich
One of the important keys to characterize the biological function of a protein is the study of post-translational modification (PTM). Formation of disulfide bond linkages between cysteine residues within a protein is a common PTM which not only contributes to folding and stabilizing the protein structure, but also to accomplishing its native function. Therefore, the study and discovery of structural-functional relationships of expressed proteins using an isolated proteomics approach has been one of the biggest advances within the field of structural biology in recent years. In this study, rapid disulfide bond mapping of freshly obtained equine serum albumin (ESA) was performed using matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). Highly sensitive MALDI-TOF MS is commonly used for the investigation of disulfide bond linkages in the proteomics field. However, it has also been known that the presence of disulfide bond linkages absorbs the energy which is created by the cysteine-cysteine kinetic vibration, resulting in a decrease of the instrumental sensitivity. To overcome this problem, the disulfide bond mapping method was optimized by applying a combination of chemical labeling, proteolytic enzymes, and matrices. With the optimized method, we were also able to achieve high protein sequence coverage. Obtaining higher sequence coverage of a protein provides more information about a protein which helps to identify the protein by peptide mass fingerprint (PMF) technique. These analyses eventually contribute to the estimation of the possible PTM sites.

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Frei, Raimundo [Verfasser], Klaus [Gutachter] Eder, and Michael [Gutachter] Corsten. "The living bond of generations : the narrative construction of post-dictatorial memories in Argentina and Chile / Raimundo Frei ; Gutachter: Klaus Eder, Michael Corsten." Berlin : Humboldt Universität zu Berlin, Philosophische Fakultät III, 2017. http://d-nb.info/112489375X/34.

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Mahindre, Prajakta Prakash. "Micro-push-out bond strength and the modes of failure for a fiber-reinforced resin-post system cemented using four adhesive luting cements." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43224052.

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Frei, Raimundo Verfasser], Klaus [Gutachter] Eder, and Michael [Gutachter] [Corsten. "The living bond of generations : the narrative construction of post-dictatorial memories in Argentina and Chile / Raimundo Frei ; Gutachter: Klaus Eder, Michael Corsten." Berlin : Humboldt Universität zu Berlin, Philosophische Fakultät III, 2017. http://nbn-resolving.de/urn:nbn:de:kobv:11-100243586.

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Abdallah, Sadoon Mushrif. "Bonding mechanisms and strength of hooked-end steel fibre reinforced cementitious composites." Thesis, Brunel University, 2017. http://bura.brunel.ac.uk/handle/2438/15827.

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Concrete is a strong material as to its compressive strength. However, it is a material with a low tensile and shear strength, and brittleness at failure. Concrete has to be reinforced with appropriate materials. Steel fibre is one of the most common materials currently being used to develop reinforced concrete, which may replace partially or completely conventional steel reinforcement. Successful reinforcement of concrete composite is closely related to the bond characteristics between the reinforcing fibre and matrix. The effective utilisation of steel fibre reinforced concrete (SFRC) requires in-depth and detailed understanding of bonding mechanisms governing the tensile behaviour. In response to this demand, this study embraced two main areas: understanding the reinforcing mechanisms of fibres in SFRC and material's post-cracking behaviour. Comprehensive experimental and theoretical programmes have therefore been developed: the experimental work is subdivided into three parts. The first part was to investigate the effect of various physical parameters, such as fibre characteristics (i.e. geometry, inclination angle, embedded length, diameter and tensile strength) and matrix strength which controls the pull-out behaviour of steel fibres. The second part is concerned with the assessment of the bond mechanisms of straight and hooked end fibres after exposure to elevated temperatures and varying matrix strength. The third part is devoted to gain further insight on the bond mechanisms governing the post-cracking behaviour through uniaxial and bending tests. It was found that the varying hook geometry and matrix strength each had a major influence on the pull-out response of hooked end fibres. As the number of the hook's bends increased, the mechanical anchorage provided by fibre resulted in significant improvement of mechanical properties of SFRC. The reduction in bond strength at elevated temperatures is found to be strongly related to the degradation in properties of the constituent materials, i.e. the fibre and concrete. The most effective combination of matrix strength and fibre geometry was found to be as follows: 3DH (single bend) fibre with normal-medium strength matrix, 4DH (double bend) fibre with high strength matrix and 5DH (triple bend) fibre with ultra-high performance matrix. Two analytical models to predict the pull-out behaviour of hooked end fibres were developed. Both models were able to predict the pull-out response of SFRC made from a variety of fibre and matrix characteristics at ambient temperature. This work has established a comprehensive database to illustrate the bonding mechanisms of SFRC and anchorage strengthening of various hooked end fibres, and this should contribute towards an increasing interest and growing number of structural applications of SFRC in construction.

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Leitune, Vicente Castelo Branco. "Influência da aplicação de um inibidor de metaloproteinases na resistência da união adesiva à dentina radicular." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/77877.

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O objetivo do presente estudo foi avaliar o efeito da aplicação de clorexidina após o condicionamento ácido na preservação da camada híbrida, avaliando a resistência de união imediata e a longo prazo de pinos de fibra de vidro cimentados à dentina radicular. Setenta e dois dentes unirradiculares superiores humanos foram selecionados. Os canais radiculares foram alargados para receberem os pinos de fibra de vidro e aleatoriamente divididos em três grupos (n=24). No Grupo Controle (Gcontrol), o pino de fibra de vidro foi cimentado de acordo com as instruções do fabricante, utilizando um sistema adesivo convencional de três passos e um cimento resinoso dual. Os grupos tratados com digluconato clorexidina GCHX0.2 e GCHX2 receberam a aplicação de solução de clorexidina 0,2% e 2%, respectivamente, após o condicionamento com ácido fosfórico e os pinos foram cimentados utilizando o mesmo sistema adesivo e cimento utilizados no Gcontrol. As raízes foram seccionadas transversalmente ao longo eixo do dente, em fatias de 0,68 (± 0,09) mm. Metade dos dentes foi submetida ao ensaio de push-out após 24 horas e a outra metade, após seis meses de armazenamento em água destilada, a 37°C. Os valores foram analisados com ANOVA de duas vias e teste de comparações múltiplas de Tukey, com nível de significância de 5%. A aplicação de clorexidina não influenciou a resistência de união quando os dentes foram avaliados no mesmo período de armazenagem (p>0,05). O tempo de armazenamento diminuiu significativamente a resistência de união de 24 horas para 6 meses, em todos os grupos (p<0,05). A aplicação de clorexidina não preveniu significativamente a degradação da resistência de união de pinos de fibra cimentados em raízes de dentes humanos, após seis meses de armazenamento.
Introduction: This study evaluated the effect of chlorhexidine applied after dentin phosphoric acid etching on hybrid layer preservation, analyzing the immediate and long-term bond strength of a fiber post cemented to root dentin. Methods: Seventy-two single-rooted, human upper teeth were selected for analysis. Root canals were enlarged for fiber post cementation and were randomly divided into three groups (n= 24). After phosphoric acid etching, each group received a different dentin treatment. In the Control Group (Gcontrol), the fiber post was cemented according to the manufacture’s instruction, using a three-step etch-and-rinse adhesive and a dual-cured resin cement. The Chlorhexidine 0.2% Group (GCHX 0.2) and the Chlorhexidine 2% Group (GCHX 2) received an application of a chlorexidine digluconate solution of 0.2% and 2%, respectively, after phosphoric acid etching, and the post was cemented using the same adhesive and cement that was used in the Gcontrol. Teeth were sectioned transversally in slices of 0.68 (± 0.09) mm. Half of the teeth were submitted to push-out bond strength after 24 hours and the other half were submitted after six months of distilled water storage at 37°C. Data were analyzed by using the two-way analysis of variance (ANOVA) and a post hoc tests using the Tukey multiple comparison test at α = 0.05. Results: Chlorhexidine application had no influence on bond strength when teeth were stored for the same period of time (p>0.05). The storage time significantly decreased the bond strength values of 24 hours to six months, in all groups (p<0.05). Conclusion: After six months, chlorhexidine application did not effectively arrest bond strength degradation of fiber post cemented in human roots.

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Kam, Weng Yuen. "Selective Weakening and Post-Tensioning for the Seismic Retrofit of Non-Ductile RC Frames." Thesis, University of Canterbury. Department of Civil and Natural Resources Engineering, 2010. http://hdl.handle.net/10092/5237.

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This research introduces and develops a counter-intuitive seismic retrofit strategy, referred to as “Selective Weakening” (SW), for pre-1970s reinforced concrete (RC) frames with a particular emphasis on the upgrading of exterior beam-column joints. By focusing on increasing the displacement and ductility capacities of the beam-column joints, simple retrofit interventions such as selective weakening of the beam and external post-tensioning of the joint can change the local inelastic mechanism and result in improved global lateral and energy dissipation capacities. The thesis first presents an extensive review of the seismic vulnerability and assessment of pre-1970s RC frames. Following a review of the concepts of performance-based seismic retrofit and existing seismic retrofit solutions, a thorough conceptual development of the SW retrofit strategy and techniques is presented. A “local-to-global” design procedure for the design of SW retrofit is proposed. Based on the evaluation of the hierarchy of strength at a subassembly level, a capacity-design retrofit outcome can be achieved using various combinations of levels of beam-weakening and joint post-tensioning. Analytical tools for the assessment and design of the SW-retrofitted beam-column joints are developed and compared with the test results. Nine 2/3-scaled exterior joint subassemblies were tested under quasi-static cyclic loading to demonstrate the feasibility and effectiveness of SW retrofit for non-ductile unreinforced beam-column connections. Parameters considered in the tests included the presence of column lap-splice, slab and transverse beams, levels of post-tensioning forces and location of beam weakening. Extensive instrumentation and a rigorous testing regime allowed for a detailed experimental insight into the seismic behaviour of these as-built and retrofitted joints. Experimental-analytical comparisons highlighted some limitations of existing seismic assessment procedures and helped in developing and validating the SW retrofit design expressions. Interesting insights into the bond behaviour of the plain-round bars, joint shear cracking and post-tensioned joints were made based on the experimental results. To complement the experimental investigation, refined fracture-mechanic finite-element (FE) modelling of the beam-column joint subassemblies and non-linear dynamic time-history analyses of RC frames were carried out. Both the experimental and numerical results have shown the potential of SW retrofit to be a simple and structurally efficient structural rehabilitation strategy for non-ductile RC frames.

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Liang, Hai-chiung, and 梁海瓊. "Micro-push-out bond strength and the modes of failure for a fibre-reinforced resin-post system cemented using three adhesive lutingcements after cyclic loading." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45591106.

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Smith, Josh E. "Mode I Fracture Toughness of Eight-Harness-Satin Carbon Cloth Weaves for Co-Cured and Post-Bonded Laminates." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1138.

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Mode I interlaminar fracture of 3k 8-Harness-Satin Carbon cloth, with identical fill and weft yarns, pre-impregnated with Newport 307 resin was investigated through the DCB test (ASTM D5528). Crack propagations along both the fill and weft yarns were considered for both post-bonded (co-bonded) and co-cured laminates. A patent-pending delamination insertion method was compared to the standard Teflon film option to assess its applicability to mode I fracture testing. The Modified Beam Theory, Compliance Calibration method, and Modified Compliance Calibration method were used for comparative purposes for these investigations and to evaluate the validity of the proposed Equivalent Stiffness (EQS) method. Crack propagation, in all specimens, proceeded in a run-arrest manner for both delamination directions. Energy dissipation in the form of transverse yarn debonding, matrix deformation, and out of plane crack growth was witnessed for specimens with delaminations along weft yarns. A complete comparison between post-bonded and co-cured laminates was not achieved. The patent pending delamination insertion method was found to cause fewer instances of non-linear crack initiation behavior than the Teflon insert and, when non-linear behavior did occur, it was less prevalent. The EQS method was found to achieve fracture toughness values within 5% of the other three data reduction methods for 63% of the propagation values and achieved conservative values for over 33% of the propagations. Suggestions for future studies aimed at completing the comparisons above are provided in Chapter 5.

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Amaral, Marina. "CONDICIONAMENTO DA SUPERFÍCIE DE PINOS DE FIBRA DE VIDRO: INFLUÊNCIA NA RESISTÊNCIA ADESIVA APÓS CICLAGEM MECÂNICA E NA RESISTÊNCIA À FLEXÃO DOS PINOS." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/6068.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Aim: To evaluate the bond strength between glass fiber post and intrarradicular dentin or core composite resin after several post surface treatments, and the effect of surface treatments on posts flexural strength. Material and methods: The following post surface treatments were evaluated: G1- no conditioning; G2- cleaning with alcohol (AL); G3- AL + silane application (SIL); G4- Al2O3 + SIL; G5- H2O2 + SIL; G6- HF + SIL; G7- H3PO4 + SIL. Tem double-tapered fiber posts from each evaluated surface treatment were cemented into bovine teeth previously embedded into acrylic resin. After, a standard composite resin cylindrical core was build up. Samples were submitted to mechanical cycling (106 cycles, 4 Hz, 37ºC) and sectioned into 2 mm slices. For root portion the bond strength was measured through push-out test, while core slices were machined into hour-glasses and submitted to microtensile bond strength test. The three point bending test was applied to cylindrical posts from G1, G4, G5, G6 and G7, to flexural strength evaluation. Moreover, two posts from these groups were conditioned for scanning electron microscopy (SEM). One-way analysis of variance followed by Tukey s test were applied to each evaluation (α=0,05). Results: the post surface conditioning had no effect on post retention into root canal (p=0,876), however the microtensile bond strength between post and composite resin was significantly affected (p<0,001), where G3 presented the highest values of bond strength. The flexural strength was also influenced by post surface conditioning, where sandblasting with Al2O3 125 μm significantly decreased the posts strength. The analysis through SEM revealed different patterns of surface s modification after conditioning. Conclusions: (1) post retention into root dentin was not affected by post surface conditioning, bust silane application promotes higher microtensile bond strength between post and composite resin; (2) sandblasting posts surface with Al2O3 125 μm decreased posts flexural strength; and (3) different patterns of surface conditioning were observed under SEM.
Objetivo: O objetivo deste estudo foi avaliar a resistência adesiva entre pino de fibra de vidro e dentina intrarradicular ou resina composta do núcleo após diferentes tratamentos de superfície dos pinos, e a influência do tratamento de superfície da resistência à flexão dos pinos. Materiais e Métodos: Os seguintes métodos para tratamento da superfície dos pinos foram avaliados: G1- sem tratamento; G2- limpeza com álcool; G3- limpeza com álcool + aplicação de silano (SIL); G4- Al2O3 125 μm + SIL; G5- H2O2 + SIL; G6- HF + SIL; G7- H3PO4 + SIL. Dez pinos de fibra de vidro duplo-cônicos condicionados com cada um dos tratamentos listados acima (n=10) foram cimentados em raízes bovinas, embutidas perpendicularmente em resina acrílica. Após, um núcleo cilíndrico padronizado foi reconstruído em resina composta. Os corpos de prova foram submetidos a 106 ciclos mecânicos (100 N, 4 Hz, 37°C, 45°) antes de serem seccionados em fatias de 2 mm de espessura. Para a porção radicular, a resistência adesiva foi medida através do teste de extrusão push-out, enquanto que para a resistência adesiva da porção coronária, foi utilizado o teste de microtração com espécimes em forma de ampulheta. Para avaliação da resistência à flexão, pinos com os tratamentos correspondentes aos grupos G1, G4, G5, G6 e G7 (n=5) foram submetidos ao teste de flexão de três pontos. Além disso, dois pinos com tratamentos de superfície destes grupos foram cobertos com ouro e submetidos à análise em MEV. Análise de variância 1-fator foi aplicada para cada uma das avaliações, seguida do teste de Tukey para contraste de médias (α=0,05). Resultados: Para retenção no canal radicular, a modificação da superfície dos pinos não foi relevante (p=0,876). Porém, a adesão entre pino de fibra e resina composta foi estatisticamente afetada pelos tratamentos de superfície (p<0,001), sendo do G3 os maiores valores de resistência adesiva à microtração. O fator de estudo também afetou a resistência à flexão: Al2O3 125μm apresentou diminuição significativa na resistência dos pinos. Sob análise em MEV, diferentes padrões de superfície foram observados após condicionamentos. Conclusões: (1) a retenção do pino no canal radicular não foi afetada pelos tratamentos sugeridos, porém a aplicação de silano na superfície do pino parece aumentar a retenção do núcleo de resina composta; (2) o jateamento da superfície dos pinos com Al2O3 125 μm pode ser danoso para as propriedades de flexão dos pinos; e (3) diferentes padrões de morfologia de superfície foram observados sob MEV.

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Menani, Luiz Ricardo. "Avaliação comparativa da influência do tratamento superficial e do agente cimentante na retenção de núcleos metálicos fundidos em titânio c.p." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-28082006-155141/.

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O uso de núcleos metálicos fundidos é comum na Odontologia Restauradora para promover a substituição de estruturas perdidas em dentes tratados endodonticamente. Estes núcleos podem ser fundidos em ligas nobres ou ligas básicas: as ligas alternativas apresentam vantagens mas são susceptíveis à corrosão. O titânio foi introduzido na Odontologia com o objetivo de compensar as deficiências dos metais básicos, principalmente a corrosão e seus produtos. Então, a proposta deste estudo foi comparar a resistência à tração de núcleos metálicos fundidos confeccionados em liga de ouro tipo III, titânio e titânio tratado superficialmente com solução de Kroll quando fixados com diferentes agentes cimentantes. Quarenta e dois caninos humanos extraídos foram selecionados, a porção coronária foi removida e a raiz remanescente foi tratada endodonticamente. Todos os espécimes foram divididos em seis grupos (n=7). O espaço para pino foi preparado a uma profundidade de 10mm usando-se brocas de Largo. Os núcleos foram fundidos em liga de ouro tipo III e titânio c.p. e fixados com cimento de fosfato de zinco ou cimento resinoso (Panavia F). A resistência à tração foi determinada em uma máquina universal de ensaios a uma velocidade de 0,5mm/min utilizando-se uma célula de carga de 50 Kgf. Os resultados foram analisados estatisticamente por ANOVA, demonstrando que não houve diferença estatisticamente significante entre os grupos. Dentro das limitações deste estudo pode-se concluir que os núcleos metálicos fundidos em titânio c.p. fixados com cimento fosfato de zinco ou cimento resinoso são uma alternativa viável aos núcleos metálicos fundidos em ouro.
The use of cast post and core is common in restorative dentistry to provide long-term tooth structure replacement for endodontically treated teeth. They could be cast in precious or basic alloys: the alternative alloys present advantages but they are susceptible to corrosion and its effects. The titanium was introduced to Dentistry with the objective of compensating the metal basic deficiencies, mainly the corrosion. Then, the purpose of this study was to compare the tensile resistance among gold alloy, titanium, and titanium after a superficial treatment with Krolls solution when fixed with different luting agents. Forty two human extracted canines were selected, the coronal aspect of each tooth was removed and the remaining root received endodontic therapy. All specimen were divided into six groups (n=7). The post space was prepared at a depth of 10mm using a Largos drill. The cast post and core were manufactured using a type III gold alloy and titanium. Cast post and core were fixed with zinc phosphate or resin luting agent (Panavia F). Tensile bond strength of the specimens was measured with a universal testing machine at a crosshead speed of 0,5mm/min and cell-load of 50 Kgf. Data (Kgf) were statistically analyzed by ANOVA. The results demonstrated that there was not a significant difference among the groups. Within the limitations of this study it has been conclude that the titanium fixed with zinc phosphate or resin luting agent is a viable alternative to the gold alloy to fabricate cast post and cores.

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Farina, Ana Paula. "Estudo ex vivo da resistência de união de pinos de fibra às paredes do canal radicular utilizando diferentes cimentos." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-19022009-163351/.

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O objetivo deste estudo foi avaliar ex vivo a resistência de união de pinos de fibra de vidro (FV) e pinos de fibra de carbono (FC) nos terços cervical, médio e apical do canal radicular, cimentados com dois tipos de cimentos resinosos: auto-adesivo (RX) e convencionais (CP). Quarenta caninos superiores foram separados em 4 grupos (n = 10) de acordo com o cimento e pino utilizado. Após a secção transversal dos dentes em fatias de 2mm de espessura, o teste de resistência adesiva (0,5mm/min) foi realizado nos terços cervical, médio e apical de cada espécime. Cinco espécimes de cada grupo foram analisados em microscopia eletrônica de varredura para observar o tipo de fratura. Os dados foram submetidos à 2-way ANOVA (Bonferroni, p< 0,05). Os resultados mostraram que os pinos de FV apresentaram os maiores valores de resistência adesiva, tanto cimentados com RX quanto com CP. Analisando especificamente o tipo de cimento, pinos cimentados com RX (FV e FC) apresentaram maiores valores de resistência adesiva (p<0,05) que CP. Para todos os grupos em estudo, a resistência de união foi maior no terço cervical, seguido pelo terço médio e apical. A análise de fratura mostrou predominância de fratura coesiva de pino para RX, sendo que para os pinos cimentados com CP houve predominância de fratura adesiva entre dentina/cimento e mista. Pode-se concluir que a resistência de união foi significativamente afetada pelo tipo de pino e também pelo tipo de cimento utilizado, sendo que os mais altos valores de resistência de união foram encontrados com a utilização de pinos de FV e cimento RX.
The objective of this study was to evaluate ex vivo the Bond strength of glass-fiber posts (GF) and carbon-fiber posts (CF) to cervical, medium, and apical thirds of root canals after luting with two types of resinous cements: Self-adhesive (RX) and conventional (CP). Forty maxillary canines were divided into 4 groups (n=10) according to the luting cement and fiber post used. After roots were perpendicularly sectioned in 2mm-thick slices, bond strength teste (0.5mm/min) were perform in coronal, midlle and apical thirds. Five specimens were selected from each group for analysis in Scanning Electron Microscopy to observe the type of fracture. The data were analyzed by 2-way ANOVA (Bonferonis test, p<0.05). The results showed that highest bond strength values to GF, for both luting cements (RX and CP). Regard the type of luting cement, posts (GF and CF) luting with RX had the best performance (p<0.05) that CP. For all groups, bond strength values were higher at cervical third, followed by midlle and apical thirds. The failure analysis demonstrated a predominance of post-cohesive failure for RX, and dentin-adhesive-cement and mixed failure for CP. It was concluded that bond strength was affected by the type of fiber post and type of luting cement, where the highest bond strength values were showed by GF-post and RX-luting cement.

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Cardenas, José Edgar Valdivia. "Avaliação da espessura de cimento e resistência adesiva de pinos de fibra de vidro cônicos em preparo para retentor intra-radicular realizados com uma ponta ultrassônica desenvolvida." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/23/23156/tde-24012018-114059/.

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Preparos para retentores intra-radiculares mais conservadores evitam desgaste desnecessário da estrutura dentinária, requer menos cimento e podem melhorar a retenção adesiva do pino. Assim o objetivo deste estudo foi avaliar a espessura de cimento ea resistência adesiva de pinos de fibra de vidro cônicos em preparo para retentor intra-radicular realizados com uma ponta ultrassônica desenvolvida. Trinta incisivos laterais superiores foram preparados com limas reciprocantes Wave One Gold (Dentsply Sirona, Ballaigues, Suiça) e aleatoriamente divididos em 2 grupos (n=15) de acordo com a técnica de preparo para pino: grupo US foram preparados com uma ponta ultrassônica desenvolvida, e grupo WP (controle) com a broca recomendada pelo fabricante do pino. Os pinos de fibra de vidro cônicos WhitePost DC 0.5 (FGM, Joinville, SC, Brasil) foram cimentados utilizando cimento resinoso dual nos terços cervical e médio do canal radicular. Isto posto, todos os espécimes foram seccionados transversalmente em três seções (cervical, média e apical do pino) para análise da área de cimento resinoso ao redor do pino que foi calculada através do programa AutoCAD, em seguida, para avaliar a resistência adesiva, o teste de cisalhamento por extrusão foi aplicado através de uma maquina de ensaio universal numa velocidade média de 0.5 mm/min até o deslocamento do conjunto restaurador intra-radicular e o tipo de falha avaliado por estereomicroscopia. A comparação entre grupos e entre terços da área de cimento e resistência adesiva foram analisadas pelo teste t independente e Anova com Tukey; e os tipos de falha entre os grupos por Mann-Whitney, todos com nível de significância de 5%. No grupo ultrassônico foi observado a menor quantidade de cimento (p<0.05) e a resistência adesiva nos diferentes grupos e terços se manifestou maior somente no terço apical do grupo ultrassônico (p<0.05). Falha adesiva entre cimento e dentina foi a mais prevalente do terço cervical e apical do grupo US e cervical de grupo WP. Falha adesiva entre cimento e pino foi a mais prevalente nos demais terços. Conclui-se que o preparo para retentor com a ponta ultrassônica desenvolvida requer menor quantidade de cimento e influencia na melhor resistência de união no terço apical do pino de fibra de vidro.
Conservative post space preparations for intra-radicular retainers prevent unnecessary desgaste of the dentin structure, require less cement and improve bond strength of the post. The aim of this study was to evaluate the influence of resin cement thickness and bond strength of prefabricated glass fiber circular postin post space preparations with an ultrasonic tip developed. Thirtymaxillarylateral incisors were prepared with Wave One Gold reciprocating files (Dentsply Sirona, Ballaigues, Switzerland) and randomly divided into 2 groups (n=15) according to the post preparation technique: gruoup US was prepared with an ultrasonic tip developed and group WP (control) with the drill recommended by the post fabricant. Every glass fiber posts WhitePost DC 0.5 (FGM, Joinville, SC, Brazil) was cemented using dual polymerizing resin cement in the cervical and middle thirdof the root canal. After that, every specimen was sectioned transversally into three sections(cervical, middle and apical of the post) and the resin cement thickness area was calculated with AutoCAD program, the bond strength test was done with an universal testing machineat medium velocity 0.5 mm/min and the failure pattern after the test was analyzed with stereomicroscopy. Datas obtained were analyzed statistically using Student\'s t-Test, ANOVA,andTukey\'s test. The comparison of failure modes between the groups in the different thirds was done using Mann-Whitney test, All of those at a 5% significance. Ultrasonic group presented thinnest layer of cement in all thirds (p<0,05), which also obtained a higher bond strength only in apical third (p<0,05). Adhesive failurebetween cement and dentinwas the most prevalent of the cervical and apical third of G1 and cervical of G2.Adhesive failure between cement and post was the most prevalent in the others thirds. It can be concluded that the postpreparation with the ultrasonic tip developed provides a smaller thickness of resin cement that influenced thebond strength in the apical third of the glass fiber post.

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Atalla, Lara Gouvêa Almeida Martins. "Influência dos agentes de limpeza cavitária na resistência ao cisalhamento por extrusão de pinos de fibra de vidro cimentados com cimento resinoso autocondicionante." Universidade Federal de Juiz de Fora (UFJF), 2009. https://repositorio.ufjf.br/jspui/handle/ufjf/3105.

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O presente estudo teve como objetivo avaliar a influência do tratamento da dentina radicular com clorexidina a 2% e ácido cítrico a 10% na resistência de união de pinos de fibra de vidro cimentados com cimento resinoso RelyX Ultimate (3M ESPE) associado a um adesivo autocondicionante Single Bond Universal (3M ESPE). Quarenta e cinco dentes humanos unirradiculares foram selecionados e seccionados na junção cemento-esmalte, padronizando-os com 14 mm de comprimento. Após tratamento endodôntico, as raízes foram divididas aleatoriamente em 3 grupos (n=15) de acordo com o tratamento prévio do conduto radicular: G1, nenhum tratamento; G2, aplicação de gel de clorexidina a 2% (Rioquímica®) por 60 segundos; G3, aplicação de ácido cítrico a 10% (Idem per Idem Farmácia de Manipulação Ltda) por 60 segundos. Posteriormente, foi aplicado o adesivo nos condutos e nos pinos de fibra de vidro (White Post, FGM) e estes foram cimentados com cimento resinoso (RelyX Ultimate - 3M ESPE), sendo fotopolimerizados por 40 segundos. As raízes foram seccionadas axialmente em discos de 2 mm e os espécimes foram submetidos ao teste de push-out. As médias dos valores obtidos (MPa) foram analisadas por meio dos testes one-way ANOVA e Tukey (α=0,05) e os tipos de falhas analisadas em estereomicroscópio com aumento de 8,0X. Os resultados mostraram que não houve diferença estatisticamente significativa entres os grupos avaliados, assim como quando comparados os terços radiculares em cada grupo (p>0,05), entretanto resultados significantes foram encontrados entre os grupos G1 e G2 na região cervical (p=0,045). Falhas mista e adesiva entre cimento e dentina foram mais prevalentes. Pôde-se concluir que o uso da clorexidina a 2% no conduto radicular pode interferir na resistência de união de pinos de fibra de vidro e que o ácido cítrico não influenciou nos resultados.
The aim of this study was to investigate the influence of root dentine treatment with 2% chlorhexidine and 10% citric acid on bond strength of fiberglass post cemented with self-etching cement. Forty five human single-rooted teeth were selected and sectioned in the cement-enamel junction, standardizing them with 14 mm length. After endodontic treatment the roots were randomly divided in 3 groups (n=15) according to the previous treatment of the root canal: G1, no treatment; G2, application of 2% chlorhexidine (Rioquímica®) for 60s; G3, application of 10% citric acid (Idem per Idem - Farmácia de Manipulação Ltda) for 60s. Subsequently, the self-etching adhesive Single Bond Universal (3M ESPE) was applied in the canals and on the fiberglass post (White Post, FGM) and these ones were cemented with resin cement (RelyX Ultimate - 3M ESPE), and light polymerized for 40s. The roots were sectioned transversely in slides of 2 mm thickness and the push-out test was performed. Data were analyzed by one-way ANOVA and Tukey test (α=0.05) and the types of failures were analyzed under stereomicroscopy (8.0X). The results show that there was no statistically significant difference between the groups, as well as when comparising bond strength in root thirds in each group (p>0.05), however, significant results were found between groups G1 and G2 in the cervical third (p=0.045). Mixed and adhesive failures between cement and dentine were predominant. It can be concluded that the use of 2% chlorhexidine in the root canal can interfere in the fiberglass posts bond strength.

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Reis, Giselle Rodrigues dos. "Efeito do revestimento com siloxano-metacrilato após deposição térmica nas propriedades adesivas e mecânicas de pinos de fibra." Universidade Federal de Uberlândia, 2015. https://repositorio.ufu.br/handle/123456789/17005.

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This study evaluated the effect of thermally deposited siloxane-methacrylate coating on bond strength glass-fiber post to core materials. Furthermore, evaluated mechanical properties of flexural strength, flexural modulus and stiffness. For bond strength, two types of GFP (Exacto, Angelus and White Post DC, FGM) were divided into eight groups (n = 13): S (control): pre-hydrolyzable silane (Prosil, FGM) was applied on the post surface; SA: silane was applied followed by one layer of adhesive (Scothbond, 3M Espe); HS: etching with 35% H2O2 (Whiteness HP Max, FGM) for one minute followed by silane; HSA: etching with H2O2 followed by silane and adhesive; Si: deposited siloxane-methacrylate coating (Si-O) by means of immersion of post in experimental solutions of5% MPTS fowled by heating at 120°C for one hour; SiS: silane application after Si-O; SiA: application adhesive after Si-O; SiSA: silane and adhesive application after Si-O. The composite resin restorations (AllCem Core, FGM) were simulated using translucent silicone molds. After 24 hours water storage at 37 °C, the post/resin assembly was serially sectioned in beams that were subjected to a microtensile bond strength test. For analysis of mechanical properties, eighteen White Post DC and eighteen Exact were used (n = 6). Post without surface treatment, etched with H2O2 and coated with siloxane methacrylate after thermally deposition had their mechanical properties evaluated skin test flexural strength of three points. The data presented normal and homogeneous distribution and subjected to two-way ANOVA and Tukey test. The results showed that the surface treatment only affected the bond strength in Exacto post (P<0.001), while for the White Post DC all groups were statistically equal to the control (22.5 ± 5.1). The highest bond strength values were obtained in SiS (40.4 ± 6.9) and SiSA (38.8 ± 5.3) groups. The etching with H2O2 (HS: 22.9 ± 2.5 and HSA: 25.5 ± 4.5) promoted increased bond strength when compared to control (15.8 ± 4.1), however, had lower values than the thermally deposition siloxane. The mechanical proprieties were not affected by surface treatment, only by the type of post, wherein Exacto post showed highest means of flexural strength, flexural modulus and lower stiffness. Thus, it is concluded that the thermally deposited siloxane-methacrylate coating is a viable option for increasing the bond strength to the core pins without alterations completion of its mechanical properties.
O objetivo desses estudo foi avaliar o efeito do revestimento de pinos de fibra com siloxano-metacrilato, após deposição térmica, na resistência de união ao núcleo de preenchimento em resina composta. Além disso, avaliou a influência deste tratamento nas propriedades mecânicas de resistência flexural, modulo de flexão e rigidez. Para avaliar a resistência de união dois tipos de pinos (White Post DC3, FGM, Produtos Odontológicos e Exacto 3, Ângelus) foram divididos aleatoriamente em oito grupos (n=13): S (controle): uma camada de silano (Prosil, FMG) foi aplicado sobre a superfície do pino; SA: aplicação de uma camada de silano, seguido do adesivo (Scothbond, 3M Espe); HS: condicionamento com H2O2 35% (Whiteness HP Max, FGM) por um minuto seguido da aplicação de silano; HSA: aplicação de H2O2 seguido da aplicação de silano e adesivo; Si: revestimento com siloxano-metacrilato após deposição térmica (Si-O), por meio da imersão em solução experimental de MTPS a 5% seguido de aquecimento a 120°C por 1 hora. SiS: aplicação de silano após Si-O; SiA: aplicação de adesivo após Si-O; SiSA: aplicação de silano e adesivo após Si-O. As restaurações em resina composta (AllCem Core, FGM) foram simuladas utilizando moldes de silicones translúcidos. Após 24h de armazenagem em água a 37ºC, as amostras foram submetidas a cortes seriados, perpendiculares ao longo eixo do pino, obtendo amostras com dimensões de aproximadamente 1x1mm, com formato de palito. As amostras foram submetidas ao ensaio mecânico de microtração à velocidade de 0,7 mm/min até o rompimento dos espécimes. Para análise das propriedades mecânicas, dezoito White Post DC e dezoito Exacto foram utilizados (n=6). Pinos sem tratamento de superfície, condicionados com H2O2 e revestidos com siloxano-metacrilato após deposição térmica tiveram suas propriedades avaliadas pelo ensaio mecânico de resistência flexural de três pontos. Os dados obtidos apresentaram distribuição normal e homogênea e foram submetidos a análise de variância fatorial de dois fatores e teste de Tukey. Os resultados demostraram que o tratamento de superfície só afetou a resistência de união no pino Exacto (P<0,001), enquanto para o White Post DC todos os grupos foram estatisticamente iguais ao controle (22,5 ± 5,1). Os maiores valores de resistência de união foram obtidos nos grupos SiS (40,4 ± 6,9) e SiSA (38,8 ± 5,3). O condicionamento com H2O2 (HS: 22,9 ± 2,5 e HSA: 25,5 ± 4,5) promoveu o aumento da resistência de união quando comparado com o controle (15,8 ± 4,1), no entanto, obteve valores menores que a deposição térmica de siloxano. As propriedade mecânicas não foram afetadas pelo tratamento de superfície, apenas pelo tipo de pino, sendo que o Exacto apresentou maiores valores de resistência flexural, modulo de flexão e menor rigidez. Dessa forma, conclui-se que a deposição térmica com siloxano-metacrilato é uma opção viável para o aumento da resistência de união dos pinos ao núcleo de preenchimento, sem alterações da suas propriedades mecânicas.
Mestre em Odontologia

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Onofre, Rafael Sarkis. "Restauração de dentes tratados endodonticamente: ensaio clínico randomizado e revisão sistemática com metánalise." Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/2247.

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The best way to restore endodontically treated teeth has been discussed in the literature because some factors can influence the post selection and the final restoration. Two of the most used intra-radicular posts are cast metal posts and glass fiber posts. Moreover, there is a large variability of in vitro studies that evaluate the use of different resin cement and the alterations of technique and the influence in the bond strength of glass fiber posts. The aims of the study were to compare the survival of two types of dental posts used to restore endodontically treated teeth with great damage of coronal walls and verify through a systematic review if there is difference on bond strength of glass fiber posts to dentin between self-adhesive and regular resin cements. Systematic review: In vitro studies that investigated the bond strength of glass fiber post luted with self-adhesive (RC) and regular (RC) were selected. Global comparison between self-adhesive (RC) and regular resin cement was performed. Two subgroup analyses were performed: self-adhesive resin cement x regular resin cement (etch-and-rinse adhesive), self-adhesive resin cement x regular resin cement (self-etch adhesive). The three analyses performed showed favorable results to self-adhesive resin cement. Clinical trial: The teeth were randomly allocated into two groups depending on the post used: glass fiber or cast metal post. Fifty-four (45 women) patients and 72 teeth were evaluated up to 3 years and the survival probabilities were 97.1% and 91.9% to cast metal posts and glass fiber posts. Four failures were observed, 2 glass fiber posts debonding (premolar and anterior tooth), 1 glass fiber post debonding associate with root fracture and 1 root fracture with a cast metal post. We can conclude that in vitro literature seems to suggest that the use of self-adhesive cement could help to achieve higher bond strength of GFPs to the root canal and after 3 years of follow up, both posts presented the same clinical performance and
A melhor maneira de se restaurar dentes tratados endodonticamente vem sendo muito discutida na literatura principalmente porque alguns fatores como a escolha do pino a ser utilizado pode influenciar o resultado final da restauração. Dois dos retentores intra-radiculares mais utilizados atualmente são os núcleos metálicos fundidos e os pinos de fibra de vidro. Além disso, existe uma grande variabilidade de estudos in vitro que avaliam tanto a utilização de diferentes cimentos resinosos como alterações das técnicas e a influência na resistência de união de pinos de fibra de vidro. O objetivo deste trabalho foi avaliar as taxas de sucesso clínico de dentes tratados endodonticamente sem remanescente coronário e restaurados com de pino de fibra de vidro ou núcleo metálico fundido através de um ensaio clínico randomizado. Além disso, realizar uma revisão sistemática da literatura de ensaios in vitro que comparassem a resistência de união de pinos de fibra de vidro cimentados com cimento resinoso regular e cimento resinoso autoadesivo. Para a revisão sistemática, estudos in vitro que avaliaram a resistência de união de pinos de fibra de vidro cimentados com cimento autoadesivo e cimento regular foram selecionados. As seguintes metánalises foram realizadas: comparação global entre cimento autoadesivo x cimento regular e análises de subgrupo cimento autoadesivo x cimento regular (adesivo etch-and-rinse) e cimento autoadesivo x cimento regular (adesivo self-etch). As três análises mostraram resultados estatisticamente significantes e favorecendo o uso de cimento autoadesivo. No ensaio clínico, os dentes selecionados foram randomizados e alocados em 2 grupos dependendo do pino utilizado. Após 3 anos, 54 pacientes (72 dentes: 35 núcleos metálicos fundidos e 37 pinos de fibra de vidro) foram avaliados. As taxas de sobrevivência foram 97,1% e 91,9% para núcleos metálicos fundidos e pinos de fibra de vidro respectivamente. Quatro falhas foram observadas: duas descimentações de pinos de fibra de vidro (pré-molar e dente anterior), uma descimentação de pino de fibra de vidro associada a fratura radicular (pré-molar) e uma fratura radicular associada ao uso de núcleo metálico fundido (molar). Conclui-se que a literatura sugere que o uso de cimento resinoso autoadesivo poderia ajudar a conseguir maior resistência de pinos de fibra vidro ao canal radicular e que após 3 anos, ambos os pinos apresentaram performance semelhante

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Higashi, Cristian. "O EFEITO DO SISTEMA DE CIMENTAÇÃO ADESIVA E TEMPO DE ARMAZENAMENTO NOS VALORES DE RESISTÊNCIA DE UNIÃO, NANODUREZA E MÓDULO DE ELASTICIDADE NO AMBIENTE INTRA-RADICULAR." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2012. http://tede2.uepg.br/jspui/handle/prefix/1810.

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The aim of this study was to assess the push-out bond strength, nanohardness and Young’s modulus of three resin cements used for luting fiber post. The measurements were taken at cervical (CT), middle (MT) and apical (AT) radicular thirds, at immediate time and after one year of storage in water. Root canals of 57 human teeth were endodontically treated and prepared to cementation of fiber post (White Post DC - FGM) using the cementation systems: Multilink [MUL] (Ivoclar Vivadent), Variolink II + Excite DSC [VAR] (Ivoclar Vivadent) and R RelyXTM Unicem [UNC] (3M ESPE). For the push-out test (n=16), after 24hs of water storage at 37ºC, half the sample (n=8) was transversely sectioned into 6 slices, being 2 slices for each radicular third, which were assess d at 0,5 mm/min. The remaining half (N=8) was kept unsectioned in deionized water at 37ºC for 1 year, followed by sectioning and measuring. For the nanoindentation test, the cemented samples (n=3) were stored in water at 37ºC for 24hs and after were longitudinally sectioned to perform the initial measurements of hardness and elastic’s modulus from cervical to apex. These same samples were stored in deionized water at 37ºC for 1 year and reassessed. The data were analyzed by three-way ANOVA and Tukey’s test (α=0.05). The mean and standard deviation of MUL bond strength (MPa) in AT (19.9 ± 3.9) was higher than MT (15.1 ± 4.7) and CT (14.9 ± 4.2) (p=0.00007). The immediate bond strength of AT (22.0 ± 4.9) decreased significantly after 1 year of water storage (15.1 ±4.1) (p=0.006). The MUL cement obtained higher values of Young’s modulus (GPa) in CT (9.2 ± 1.9) when compared to MT (6.6 ± 2.0) e AT (5.4 ± 2.6)(p=0.01). The AT has the lowest values of hardness (GPa) (0.40 ± 0.10) when compared to MT (0.45 ± 0.12) and CT (0.48 ± 0.11) (p=0.000001). The initial hardness of UNC cement (0.43 ± 0.12) decreased after 1 year of storage in water (0.35 ± 0.14) (p=0.0051). It was concluded that: 1) The bond strength of MUL cement was higher in AT, 2) The AT of the cements suffered higher bond degradation after 1 year of storage water, 3) The Young’s modulus of MUL cement was higher in CT, 4) The AT of all cements had lowest hardness values, 5) After 1 year of storage in water, the UNC cement had a significant decreased of hardness values.
O objetivo deste trabalho foi avaliar a resistência de união, nanodureza e módulo de elasticidade de 3 cimentos resinosos utilizados para cimentar pinos de fibra de vidro. As mensurações foram feitas nos terços cervical [TC], médio [TM] e apical [TA] das raízes, no tempo imediato e após 1 ano de armazenamento em água destilada. Os canais radiculares de 57 dentes humanos unirradiculares foram tratados endodonticamente e preparados para a cimentação dos pinos de fibra de vidro White Post DC (FGM) utilizando os sistemas de cimentação Multilink [MUL] (Ivoclar Vivadent), Variolink II + Excite DSC [VAR] (Ivoclar Vivadent) e RelyXTM Unicem [UNC] (3M ESPE). Para o teste de push-out (n=16), após 24hs de armazenamento em água destilada à 37ºC, metade das amostras (n=8) foram cortadas transversalmente em 6 fatias, sendo 2 fatias para cada terço radicular, que foram testadas à velocidade de 0,5 mm/min. A outra metade das amostras cimentadas (n=8) foram mantidas íntegras em água destilada à 37ºC por 1 ano, seguidos pelos cortes e mensurações. Para o teste de nanoindentação, as amostras cimentadas (n=3) foram armazenadas em água à 37ºC por 24hs e logo após, cortadas longitudinalmente aos seus longos eixos para a realização das mensurações iniciais de nanodureza e módulo de elasticidade do TC até TA. Estas mesmas amostras foram armazenadas em água destilada à 37ºC por 1 ano e retestadas. Os dados foram submetidos a uma análise de variância de três critérios e ao teste de Tukey (α=0,05). A média e desvio padrão dos valores de resistência de união (MPa) do cimento MUL no TA (19,9 ± 3,9) foi maior do que no TM (15,1 ± 4,7) e TC (14,9 ± 4,2) (p=0,00007). A resistência de união imediata do TA (22,0 ± 4,9) diminuiu significativamente após 1 ano de armazenamento em água (15,1 ± 4,1) (p=0,006). O cimento MUL obteve maiores valores de módulo de elasticidade (GPa) no TC (9,2 ± 1,9) em compara ão ao TM (6,6 ± 2,0) e TA (5,4 ± 2,6) (p=0,01). O TA radicular teve os menores valores de nanodureza (GPa)(0,40 ± 0,10) quando comparado com os TM (0,45 ± 0,12) e TC (0,48 ± 0,11) (p=0,000001). A nanodureza inicial do cimento UNC (0,43 ± 0,12) diminui após 1 ano de armazenamento em água (0,35 ± 0,14) (p=0,0051). Concluiuse que: 1) A resistência do cimento MUL foi maior no TA; 2) O TA dos cimentos sofreu uma maior degradação da união após o armazenamento de 1 ano em água; 3) O módulo de elasticidade do cimento MUL foi maior no TC; 4) O TA de todos os cimentos teve menores valores de dureza; 5) O cimento UNC teve uma diminuição significativa dos valores de nanodureza após 1 ano de ar azenamento em água. Palavras-chave: Cimento resinoso. Pino de fibra. Dentina radicular.

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Castellan, Carina Strano. "Avaliação dos ensaios de microtração, push-out e pull-out: resistência de união entre pino de fibra e dentina radicular, análise de elementos finitos e microscopia confocal." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/23/23140/tde-18102007-071955/.

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O objetivo deste estudo foi comparar os ensaios de microtração (MI), ?push-out? (PS), ?push-out? modificado (PSM) e ?pull-out? (PL) na habilidade de mensurar a resistência de união (RU) entre pino de fibra e dentina radicular. Para tanto, além dos resultados de cada ensaio mecânico foram analisados fatores como: sensibilidade quanto às diferentes regiões radiculares, quantidade de falhas prematuras (FP), coeficiente de variação (CV), padrão de fratura (PF) pela microscopia confocal de varredura e distribuição das tensões pela análise de elementos finitos (AEF). Foram utilizados 40 dentes anteriores superiores endodonticamente tratados, divididos em quatro grupos de acordo com o tipo de ensaio realizado. Para os ensaios de PS e MI foi feita a cimentação do pino e posteriormente os cortes para a obtenção dos corpos-de-prova (cps). Para os outros ensaios (PSM e PL), a cimentação antecedeu aos cortes tanto das fatias de dentina como dos pinos. O sistema adesivo Scotbond Multi Uso Plus e o cimento Variolink II foram usados para a cimentação do pino de fibra de vidro FRC Postec Plus em todos os casos. Os cps do ensaio de PS foram obtidos pelos cortes seriados da raiz em fatias de 1±0,1mm, para os cps do ensaio de MI estas fatias sofreram ainda a confecção de entalhes laterais diametralmente opostos, que proporcionando um formato final de ampulheta. Para os testes de PL e PSM foram feitos cortes de fatias de dentina de 1±0,1mm e o pino foi dividido em três partes iguais para, então, cada fatia de uma região ser cimentada com o pino correspondente. Os cps do ensaio de PSM tinham 1mm de pino sobressalente para cima e para baixo da fatia de dentina, enquanto que os cps do PL o pino sobressalente estava apenas para cima da dentina. Todos os cps foram submetidos aos testes de RU, à velocidade de 0,5mm/min em máquina de ensaios universais. O PF foi avaliado em um aumento de cem vezes e foi feita uma distribuição de freqüência. Já a AEF obteve modelos tridimensionais de todos os ensaios, e estes foram analisados quanto à tensão de Von Mises. Para os resultados dos testes mecânicos foram feitas análises de variância de cada ensaio variando o fator região, com ou sem as FP, e análise comparando todos os ensaios. O teste Tukey foi feito quando necessário e as FP foram submetidas ao teste estatístico de Fisher. A inclusão ou não destas falhas mostra alteração dos resultados no ensaio de MI, uma vez que possui um maior número delas neste ensaio. O ensaio de PL mostrou as maiores médias de RU, seguido pelo ensaio de PSM, e ambos também tiveram o PF com maior quantidade de fraturas adesivas. O ensaio de PS conseguiu apontar diferença estatística entre as três regiões, mas mostrou a maior freqüência de falhas coesivas, e maior CV. O menor CV foi encontrado para o PSM que também mostrou uma adequada distribuição das tensões. A MI apresentou concentração de tensões nas bordas dos entalhes. Concluiu-se que o tipo de ensaio influencia diretamente nos resultados obtidos.
The aim of this study was to compare microtensile (MI), \"push-out\" (PS), modified \"push-out\" (PSM) and \"pull-out\" (PL) tests in the ability to accurately measure the bond strength of fiber posts luted inside root canals, at different root dentin levels, cervical, middle and apical. The evaluated parameters were: amount of premature failure (PF), coefficient of variation (CV), failure patterns (FP) and the stress distribution by finite elements analysis (FEA). Forty human intact single-rooted and endodontically treated teeth were divided into four groups according to the type test used. For PS and MI specimens, first the post was luted and then the cuts were done, for PSM and PL, first was done the cuts and then fiber post?s pices were luted. Scotbond Multi Use Plus adhesive system and Variolink II cement had been used for luting FRC Postec Plus glass fiber post, in all cases. PS samples were disc shaped of 1±0,1mm. Bond strength between post and dentin was measured in the root slice and the force applied on the center of the specimen. For the Mi test hourglass-shaped samples were obtained by trimming the proximal surfaces of each slice using a diamond bur until it touched the post. For PL and PSM tests cuts of 1±0,1mm of dentine slices were made and the fiber was divided into three parts, and then each slice were luted with a fiber post?s piece. Specimens for PSM had 1mm of post up and down the dentin slice and for PL all of the post was up the dentine slice. All specimens were submitted to a bond strength test at 0.5 mm/minute crosshead speed in a universal testing machine. For FP, each sample was examined under confocal microscopy at 100 times and a frequency distribution was made. For the AEF, three-dimensional models of each tests had been made and analyzed by Von Mises stress. Bond strength data were analyzed by ANOVA and when necessary was used Tukey?s test. For PF data the Fisher test was made. The inclusion of PF, only shows variation on MI, since these test showed the greater number of them. PL provided higher values of bond strength for root dentin and fiber post, followed by PSM. Both of them had also FP with greater amount of adhesive failures. The PS test was able to point statistically differences between root regions, but it showed the highest frequency of cohesive failure, and greater CV. Minor CV was found for the PSM that also showed adequate stress distribution. The MI showed concentration of tensions in the edges of the trimming area. One concluded that the type of test influences directly in the results obtained.

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Santana, Fernanda Ribeiro. "Influência da terapia endodôntica e do envelhecimento artificial acelerado na resistência de união de pinos de fibra de vidro à dentina intrarradicular." Universidade Federal de Goiás, 2012. http://repositorio.bc.ufg.br/tede/handle/tede/4270.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Aim: To evaluate in vitro the influence of root canal instrumentation techniques, endodontic irrigants, endodontic sealers and artificial accelerated aging on fibreglass post bond strength to bovine intraradicular dentine. Methodology: Part 1. 120 bovine incisors were divided into 12 experimental groups (n=10) resulting from the interaction among 3 study factors: root canal instrumentation technique (RCPSS- root canal preparation with stainless steel instruments - KFile; RCPNiTi- root canal preparation with K3 Nickel-Titanium instruments), endodontic irrigant (NaOCl- 1% sodium hypochlorite; CHX- 2% chlorhexidine; O3- 1.2% ozonated water) (in all samples 17% EDTA was used to remove the smear layer) and specimens artificial accelerated aging (Immediate, test with no aging; Mediate, test performed after 2 months of water storage at 37°C). After root canal preparation, endodontic filling was not performed. Fibreglass posts were cemented with self-adhesive resin cement (RelyX U100, 3M-ESPE) and roots were cross-sectioned to obtain two slices of each third. Samples were submitted to micropush-out test and bond strength values (MPa) were analyzed by ANOVA in a split-plot arrangement and Tukey’s test (α = 0.05). Failure modes were evaluated under a confocal microscope. Part 2. 60 bovine incisors were divided into 6 experimental groups (n=10) resulting from the interaction between 2 study factors: endodontic sealer (Sx- Sealapex; S26- Sealer 26; AHAH Plus) and specimens artificial accelerated aging (Immediate, test with no aging; Mediate, test performed after 2 months of water storage at 37°C). Two control groups were employed (without root canal filling), represented by groups RCPNiTiNaOCl immediate and RCPNiTiNaOCl mediate of part 1 of the present study. In the six experimental groups, root canals were prepared 1mm from the apex with K3 Nickel-Titanium instruments associated with 1% sodium hypochlorite irrigation and 17% EDTA. They were then filled with gutta-percha and the specific sealer of each group, using the lateral compaction technique. Fibreglass posts were cemented with self-adhesive resin cement (RelyX U100, 3M-ESPE) and roots were cross-sectioned to obtain two slices of each third. Abstract xx Samples were submitted to micropush-out test and bond strength values (MPa) were submitted to ANOVA in a split-plot arrangement and Tukey’s test (α = 0,05). Comparisons with control groups were made using Dunnet test (α = 0.05). Failure modes were evaluated under a confocal microscope. Results: Part 1. In specimens submitted to water artificial aging, RCPNiTi presented higher bond strength values than RCPSS in apical third irrigated with NaOCl or CHX. Irrigation with NaOCl resulted in higher bond strength than O3. Artificial aging resulted in significant bond strength increase, except for middle and apical thirds of RCPSSO3 and apical of RCPNiTiO3. Bond strength significantly reduced in apical third. The prevalence of adhesive cement-dentine failure was verified in all groups. Part 2. Endodontic sealers showed no significant differences among them, however they presented significantly lower bond strength values than control groups (without filling), except in cervical third of groups tested immediately. Artificial aging did not interfere on bond strength to intraradicular dentine. There was a significant decrease on bond strength from cervical to apical third. The prevalence of adhesive cement-dentine failure was verified in all groups. Conclusions: Part 1. Root canal preparation with NiTi instruments associated with NaOCl irrigation and EDTA increased the bond strength of fiberglass posts cemented with self-adhesive resin cement to intraradicular dentine. Part 2. Endodontic sealers interfered negatively on bonding of fibreglass posts cemented with self-adhesive resin cement to intraradicular dentine.
Objetivo: Analisar in vitro a influência das técnicas de instrumentação do canal radicular, dos irrigantes e cimentos endodônticos e do envelhecimento artificial acelerado na resistência de união do pino de fibra de vidro à dentina intrarradicular em dentes bovinos. Metodologia: Parte 1. Cento e vinte incisivos bovinos foram divididos em doze grupos experimentais (n=10) resultantes da interação entre três fatores em estudo: técnica de instrumentação do canal radicular (PAI – preparo do canal radicular com instrumentos de aço inoxidável - K-File; PNiTi – preparo do canal radicular com instrumentos de Níquel-Titânio - K3); irrigante endodôntico (NaOCl- hipoclorito de sódio 1%; CHX- clorexidina 2%; O3- água ozonificada 1,2%) (em todas as amostras o EDTA 17% foi utilizado para a remoção de smear layer) e envelhecimento artificial acelerado dos espécimes (Imediato, teste sem envelhecimento; Mediato, teste após 2 meses de envelhecimento em água a 37°C). Após o preparo dos canais radiculares não foi realizada a obturação endodôntica. Pinos de fibra de vidro foram cimentados com cimento resinoso auto-adesivo (RelyX U100, 3M-ESPE) e as raízes foram seccionadas para obtenção de duas fatias de cada terço. As amostras foram submetidas ao teste de micropush-out e os dados de resistência de união (MPa) foram analisados por ANOVA com parcela subdividida e teste de Tukey (α = 0,05). Os padrões de falha foram avaliados por meio de microscopia confocal. Parte 2. Sessenta incisivos bovinos foram divididos em seis grupos experimentais (n=10) resultantes da interação entre dois fatores em estudo: cimento endodôntico (SX- Sealapex; S26- Sealer 26; AH- AH Plus) e envelhecimento artificial acelerado dos espécimes (Imediato, teste sem envelhecimento; Mediato, teste após 2 meses de envelhecimento em água a 37°C). Foram empregados dois grupos controles (sem obturação do canal radicular) representados pelos grupos PNiTiNaOCl imediato e PNiTiNaOCl mediato da parte 1 do presente estudo. Nos seis grupos experimentais os canais radiculares foram preparados 1mm aquém do ápice com instrumentos de Níquel-Titânio - K3 associado a Resumo xviii irrigação com NaOCl 1% e EDTA 17%. Em seguida, foram obturados com gutapercha e o cimento endodôntico específico de cada grupo, usando a técnica de condensação lateral. Pinos de fibra de vidro foram cimentados com cimento resinoso auto-adesivo (RelyX U100, 3M-ESPE) e as raízes foram seccionadas para obtenção de duas fatias de cada terço. As amostras foram submetidas ao teste de micropush-out e os dados de resistência de união (MPa) foram analisados por ANOVA com parcela subdividida e teste de Tukey (α = 0,05). Comparações com os grupos controles foram feitas pelo teste de Dunnet (α =0,05). Os padrões de falha foram avaliados por meio de microscopia confocal. Resultados: Parte 1. Nos espécimes submetidos ao envelhecimento artificial em água, PNiTi apresentou maiores valores de resistência de união que PAI no terço apical irrigado com NaOCL ou CHX. A irrigação com NaOCL resultou em maior resistência de união comparada a O3. O envelhecimento artificial resultou em aumento significante da resistência de união, exceto para os terços médio e apical de PAIO3 e apical de PNiTiO3. A resistência de união reduziu significativamente no terço apical. A prevalência de falha adesiva cimentodentina foi verificada em todos os grupos. Parte 2. Os cimentos endodônticos não mostraram diferenças significantes entre si, entretanto apresentaram valores de resistência de união significativamente menores que os grupos controles (sem obturação), exceto no terço cervical dos grupos testados imediatamente. O envelhecimento artificial não interferiu na resistência de união à dentina intrarradicular. Houve uma diminuição significante na resistência de união do terço cervical para o apical. A prevalência de falha adesiva cimentodentina foi verificada em todos os grupos. Conclusões: Parte 1. O preparo do canal radicular com instrumentos de NiTi associado a irrigação com NaOCl e uso do EDTA aumentou a resistência de união de pinos de fibra de vidro cimentados com cimento auto-adesivo à dentina intrarradicular. Parte 2. Os cimentos endodônticos interferiram negativamente na união de pinos de fibra de vidro cimentados com cimento auto-adesivo à dentina intrarradicular.

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Soares, Leandro Passos. "Influência de diferentes métodos de condicionamento superficial em pinos pré-fabricados resinosos fibro-reforçados em vidro e quartzo na resistência adesiva a compósito de polimerização dual: teste de push-out." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=3504.

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O objetivo deste estudo foi realizar uma avaliação tridimensional da rugosidade superficial em 3 tipos de pinos de fibra - DT LightPost, FRC Postec Plus e Transluma Post - submetidos a diferentes tratamentos de superfície e avaliar os efeitos dos pré-tratamentos na resistência adesiva a um compósito de presa dual Biscore. Os tratamentos de superfície foram: imersão em ácido hidrofluorídrico, jateamento com óxido de alumínio a 50m, imersão em peróxido de hidrogênio, jateamento com óxido de alumínio a 50m seguido de imersão em ácido hidrofluorídrico e jateamento com óxido de alumínio a 50m seguido de imersão em peróxido de hidrogênio. No experimento 1, 75 pinos foram divididos em 3 grupos (n = 25), de acordo com seu fabricante e subdivididos em cinco subgrupos. A rugosidade superficial foi medida usando um rugosímetro tridimensional e analisada com o software de análise 3D. Os valores de rugosidade foram obtidos antes e após diferentes tratamentos de superfície na área dos mesmos corpos-de-prova. Para o experimento 2, foram utilizados os mesmos corpos-de-prova, os mesmos grupos e subgrupos do experimento 1, tendo sido adicionado o subgrupo de controle (n=90) e a resistência adesiva a um compósito presa dual Biscore foi mensurada através de um teste push-out. A resistência adesiva foi medida em uma máquina universal de ensaios, com uma célula de carga tipo SLBL-5kN em uma velocidade de 0,5 mm / min. Os resultados do experimento 1 foram analisados através de um teste estatístico t-Student. Jateamento e jateamento seguido de imersão em ácido hidrofluorídrico produziram um aumento estatisticamente significante na rugosidade, contudo somente o tratamento por jateamento proporcionou um aumento significativo nos valores de rugosidade. Os resultados do experimento 2 foram obtidos através de um um teste t-unilateral de hipótese com variância desconhecida. Concluiu-se que o jateamento com óxido de alumínio a 50μm em uma distância de 30 mm a 2,5 bar de pressão por 5 segundos foi suficiente para modificar a topografia dos pinos de fibra de vidro e quartzo e que o jateamento com partículas de 50 μ alumina a distância de 30 mm a 2,5 bar de pressão por 5 segundos foi o único tratamento de superfície que aumentou a resistência adesiva do compósito Biscore aos pinos DT Light Post e Transluma Post. Os pinos FRC Postec Plus não demostraram um aumento estatisticamente significante na resistência adesiva em nenhum grupo.
The aim of this study was to perform a tridimensional surface roughness test evaluation of different surface treatments to 3 types of fiber posts - DT LightPost, FRC Postec Plus e Transluma Post - and evaluate the effects of the different pretreatments on the bond strength of a dual-cure resin core material Biscore. The different surface treatments were: immersion in hydrofluoric acid, sandblasting abrasion with 50 alumina particles, immersion in hydrogen peroxide, sandblasting abrasion with 50 alumina particles followed by immersion in hydrofluoric acid and sandblasting abrasion with 50 alumina particles followed by immersion in hydrogen peroxide. In the first experiment seventy five fiber posts were divided into 3 groups (n = 25), according to their manufacturer and subdivided into 5 subgroups. Surface roughness was measured using a tridimensional surface roughness test and analyzed with 3D analysis software. Surface roughness was obtained before and after the different surface treatments at the same post area. In the second experiment the same samples divided in groups and subgroups were used, but a control group (no treatment) was added (n = 90) and the bond strength to a composite resin core material Biscore was measured using a push-out design. The interfacial push-out bond strength was measured in a universal testing machine, with a load cell type SLBL-5kN at a crosshead speed of 0.5 mm/min. Results in experiment 1 were statistically analyzed using Students t-Test. Sandblasting and sandblasting followed by immersion in hydrofluoric acid produced a significant increase in roughness, but the sandblasting treatment was able to provide a significant roughness increase. Results in experiment 2 were statistically analysed using one-sided t-Test of Hypothesis with unknown variance. It was concluded that sandblasting airborne-particle abrasion with alumina 50 at a distance of 30 mm at 2.5 bars pressure for 5 seconds was sufficient to modify the surface topography of glass and quartz fiber posts and the sandblasting abrasion with 50 alumina particles at a distance of 30 mm at 2.5 bars pressure for 5 seconds was the only surface treatment in DT Light Post and Transluma Post that increased the bond strength to dual cure resin composite cores. FRC Postec Plus post did not shown an increase in bond strength in any group.

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Junior, José Quinto. "Laser de Er,Cr:YSGG em condutos radiculares preparados para cimentação de núcleos protéicos." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-05032012-103954/.

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O objetivo deste estudo é avaliar a influência da irradiação com laser de Er,Cr:YSGG no espaço protético de condutos radiculares preparados para a fixação de pinos em fibra de vidro reforçados (FRC Postec®), avaliando-se o comportamento de três diferentes técnicas adesivas (self-etching= Panavia F®; total-etching= Excite DSC® + Variolink II® e self-adhesive= RelyX Unicem Aplicap®). Observaram-se as orientações da norma ISO-TS 11405 para a preparação das raízes dentais unirradiculares humanas. As amostras foram separadas na altura da junção amelo-dentinaria, tratadas endodonticamente com instrumentação rotatória e seladas com técnica de condensação lateral. Foram utilizados dois tipos diferentes de pontas de safira para irradiação intracanal o axial (Z4, 400 m de diâmetro) e o radial ou side firing (RFT4, 415 m de diâmetro) com densidade de energia de 40 J/cm2. Esta densidade de energia foi obtida como parte deste experimento, analisando-se diversos parâmetros de energia com os resultados morfológicos e térmicos obtidos. Nesta densidade, obtive-se grande quantidade de túbulos dentinários abertos e variação de temperatura segura para uso clínico. Cada raiz foi irradiada em cinco movimentos circulares, de apical para cervical, com intervalo de 20 segundos, entre elas. Os FRC Postec foram cimentados imediatamente após a irradiação e divididos randomicamente em nove grupos (n=10). Cada raiz foi seccionada em 6 discos de 1 mm de espessura para ensaio do tipo push-out, para a obtenção da força máxima de ruptura, e posterior cálculo da resistência de união adesiva em função da área de superfície do núcleo deslocado, resultando na pressão em MPa. A resistência de união adesiva nos grupos irradiados foi estatisticamente superior do que os grupos controle. Foram avaliadas as diferenças na resistência de união adesiva em diferentes porções do núcleo (cervical, médio e apical), onde o sistema adesivo tipo self-adhesive (RelyX Unicem Aplicap) teve o melhor resultado para os grupos irradiados. Avaliou-se por técnica de FTIR as diferenças químicas ocorridas na dentina intrarradicular irradiada com laser de Er,Cr:YSGG, em diferentes porções (cervical, médio e apical) em função da orientação dos túbulos. Foram observadas nos espectros de FTIR alterações na intensidade das bandas de algumas moléculas, indicando variação na quantidade da parte orgânica (amida I e amida II) após a irradiação, nas diferentes regiões dentais em função do feixe laser sobre a orientação dos túbulos dentinários, sem causar alterações na sua composição. Essas diferenças podem interferir no resultado da resistência de união adesiva. A técnica de utilização de laser de Er,Cr: YSGG em dentina radicular pré-cimentação de núcleo protético aumenta a resistência de união adesiva, na dependência do cimento utilizado.
The aim of this study was to evaluate the influence of the Er,Cr:YSGG laser irradiation in the prosthetic post space before FRC Postec placement using three different adhesive systems (self-etching- Panavia F; total-etching- Excite DSC + Variolink II e self adhesive - RelyX Unicem Aplicap). According to ISO-TS 11405, sectioned at the CEJ, human dental single roots were endodontically treated with rotatory instruments and filled with gutta-percha points and sealer. Were used at 40 J/cm2 an axial Z4 laser tip (400 m diameter) and a radial (side firing) RFT4 laser tip (415 m diameter). This density of energy was experimentally determinated observing morphological changes in SEM images due to an increase range in the energy applied to dentinal root canal surface. At the length between 32 and 49 J/cm2 most of the intracanal dentinal tubules were open. The temperature increase was within the biological safe suggesting a feasible clinical use. Each root canal was irradiated five times with helicoidal movements from apical to cervical, with 20 seconds interval. FRC Postec were immediately cemented and randomly divided in nine groups (n=10). Each root canal was cut in six discs for push out test, were the maximum failure load was obtained and the bond strength was calculated as a function of post bonded area. The bond strength for the irradiated groups was superior among all control groups. The evaluation of bond strength among root region (cervical, middle and apical) was performed and differences were observed. The self-adhesive (RelyX Unicem Aplicap) system was noted superior among all irradiated groups and all regions. Chemical changes were analyzed by FTIR due to dental root portion and dentinal tubules orientation to laser beam direction. The FTIR spectra obtained indicated changes due to tubules orientation and root canal portion irradiated such as the proportion among the compositional ratio without causing chemical changes. These compositional ratio alterations may affect the bond strength results. The irradiation with Er,Cr:YSGG laser on dentinal walls of a prosthetic post space preparation before the post cementation, as suggested in this study, may increase the bond strength between the post and root canal dentin depending upon the luting cement that is used.

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Williams, Charlotte. "Posttraumatic stress following childbirth and maternal perceptions of the mother-infant bond : the role of attachment experiences and metacognition." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7785.

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Background: Some women develop symptoms of posttraumatic stress following childbirth. There is preliminary evidence that cognitive variables may be associated with the development or maintenance of these symptoms. Research indicates that symptoms of posttraumatic stress following childbirth may have negative consequences for mother-infant relationship outcomes. However, these may be attributable to comorbid symptoms of depression. Further evidence is required regarding the nature of the relationships between these variables. Methods: An internet based cross-sectional questionnaire design was employed to test hypothesised relationships between maternal attachment experiences, metacognition, symptoms of PTSD and depression and perceptions of the mother-infant bond, in an analogue sample of new mothers. Structural equation modelling was employed for the principal analysis. Results: The final structural model demonstrated a good fit to sample data. Metacognition fully mediated the relationship between attachment experiences and postnatal psychological outcomes. The association between posttraumatic stress and maternal perceptions of the mother-infant bond was fully mediated by depression. Conclusions: Metacognition may have a key role in the development and maintenance of postnatal psychological distress. If clinically significant postnatal depression is identified, screening for posttraumatic stress is strongly indicated.

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Sanchez, Joana. "Un imaginaire du lien : famille et société dans le théâtre indépendant argentin (1975-2015)." Thesis, Strasbourg, 2019. https://publication-theses.unistra.fr/restreint/theses_doctorat/2019/Sanchez_Joana_2019_ED520.pdf.

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À partir d’une approche transdisciplinaire croisant la sociologie, l’anthropologie, l’histoire et la philosophie, il s’agit d’abord de penser comment la famille, lieu quotidien d’un maillage dialectique entre le même et l’autre, peut être le support privilégié d’un « imaginaire du lien ». C’est au regard de cette hypothèse, et depuis une perspective sociocritique, que la thèse questionne les croisements entre le lien familial (exposé sur la scène), le lien social (qui s’y projette, par la médiation de l’imaginaire) et le lien théâtral (qui structure les dramaturgies et définit une théâtralité spécifique), durant deux périodes particulièrement complexes d’un point de vue socio-politique : la dernière dictature militaire puis la post-dictature. À la croisée des études théâtrales et des sciences sociales, cette recherche explore les enjeux politiques et sociaux du sujet, tout en plaçant l’analyse dramaturgique du corpus au premier plan de la démonstration
From a transdisciplinary approach at the crossroads of sociology, anthropology, history and philosophy, this research, in a first instance, considers how the family, everyday playground of a dialectic mesh between the same and the other, can be the privileged substrate of an “imaginary of the bond”. In the light of this hypothesis, and through the social criticism, this thesis interrogates the intersections between family bond (exhibited on stage), social bond (projected on it) and theatrical bond (which structures the dramaturgy and defines a specific theatricalness), during two timeframes particularly intricate on a socio-political standpoint: the last military dictatorship and the post-dictatorship. On the crossroads of theatrical studies and social sciences, this research explores political and social issues while bringing to the forefront the dramaturgical analysis of the corpus
¿Por qué el teatro, y en particular en Argentina, parece tan obsesionado con el tema de la familia ? Rechazando la retórica de la «familia disfuncional», esta tesis analiza las ficciones familiares en su relación con lo social. Desde una perspectiva pluridisciplinar (con herramientas de sociología, antropología, historia y filosofía), se trata primero de pensar cómo la familia, espacio cotidiano de una dialéctica entre lo mismo y lo otro, puede ser el soporte de un «imaginario del vínculo». A partir de esta hipótesis, y con las herramientas de la teatrología y la sociocrítica, la tesis interroga los cruces entre vínculo familiar, vínculo social y vínculo teatral (el que estructura la dramaturgia y la teatralidad), durante dos períodos complejos a nivel sociopolítico: la última dictadura militar y la posdictadura. Respecto al teatro producido durante la dictadura, se matiza la idea de una intención sistemáticamente metafórica (al asumir que un teatro concebido como mero código sería un vínculo teatral profundamente vertical que no corresponde con gran parte de las obras), y se analizan «manchas temáticas» recurrentes, que plasman en las ficciones familiares un «vínculo tiránico», a la par de la política de terror de la Junta militar.En la posdictadura, se sigue profundizando una dinámica de fragmentación social, que también se puede vislumbrar en la producción teatral. Mientras que las condiciones de producción del teatro independiente (en espacios cada vez más íntimos) favorecen la multiplicación de dramas familiares, las nuevas dramaturgias, a pesar de reivindicar su autonomía, también están atravesadas por el contexto social e histórico (mediante motivos temáticos recurrentes y formas dramáticas fragmentadas). Entre los estudios teatrales y las ciencias sociales, este trabajo de investigación explora la dimensión política y social del tema familiar, con el análisis dramatúrgico del corpus en el primer plano de la reflexión

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Sabri, Amirreza. "Seismic Retrofit of Load Bearing URM Walls with Internally Placed Reinforcement and Surface-Bonded FRP Sheets." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40675.

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Concrete block masonry is a common building material used worldwide, including Canada. Reinforced masonry buildings, designed according to the requirements of recent building codes, may result in seismically safe structures. However, unreinforced masonry (URM) buildings designed and constructed prior to the development of modern seismic design codes are extremely vulnerable to seismic induced damage. Replacement of older seismically deficient buildings with new and seismically designed structures is economically not feasible in most cases. Therefore, seismic retrofitting of deficient buildings remains to be a viable seismic risk mitigation strategy. Masonry load bearing walls are the most important elements of such buildings, potentially serving as lateral force resisting systems. A seismic retrofit research program is currently underway at the University of Ottawa, consisting of experimental and analytical components for developing new seismic retrofit systems for unreinforced masonry walls. The research project presented in this thesis forms part of the same overall research program. The experimental component includes design, construction, retrofit and testing of large-scale load bearing masonry walls. Two approaches were developed as retrofit methodologies, both involving reinforcing the walls for strength and deformability. The first approach involves the use of ordinary deformed steel reinforcement as internally added reinforcement to attain reinforced masonry behaviour. The second approach involves the use of internally placed post-tensioning tendons to attain prestressed masonry behaviour. The analytical component of research consists of constructing a Finite Element computer model for nonlinear analysis of walls and conducting a parametric study to assess the significance of retrofit design parameters. The results have led to the development of a conceptual retrofit design framework for the new techniques developed, while utilizing the seismic provisions of the National Building Code of Canada and the relevant CSA material standards.

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Pelouch, Adam. "Řešení statického zajištění přístavby stávajícího objektu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2021. http://www.nusl.cz/ntk/nusl-444632.

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Diploma thesis is focused on structural assessment and strengthening of the reinforced concrete flor slab disturbed by excessive deflection. Thesis included assesment of the existing construction and design method of strengthening of the floor structure with system using prestressing strands without bond.

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Ramozzi, Romain. "Etude expérimentale et théorique des couplages de type Ugi et nouvelles réactions de post condensations." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2013. http://tel.archives-ouvertes.fr/tel-00945920.

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Les réactions de type Ugi sont connues depuis une cinquantaine d'années. Ces réactions multicomposants mettent en jeu un aldéhyde, une amine, un isonitrile ainsi qu'un dérivé acide (acide carboxylique ou phénol activé). Dans ces travaux, la structure électronique des isonitriles, composé au coeur de ces réactions a été étudiée. La forme carbénique RN=C s'est révélée majoritaire contrairement à toute attente. La linéarité de la molécule a pu être interprétée grâce aux contributions des formes minoritaires. La seconde partie s'est focalisée sur l'étude théorique et expérimentale des couplages de type Ugi. Contrairement à la réaction de Ugi-Smiles, le réarrangement final de la réaction de Ugi, un réarrangement de Mumm, s'est révélé non cinétiquement déterminant. L'importance du rôle de l'environnement a été étudiée par le biais d'une microsolvatation. La compréhension accrue de la réaction de Ugi-Smiles a fait émerger deux nouveaux partenaires acides : les trichlorophenols et les nitrosophenols. Les premiers ont permis d'isoler pour la première fois desaryl-imidates de phénol. Les seconds ont été utilisés pour développer une nouvelle voie de synthèse debenzimidazoles à partir des adduits de Ugi-Smiles correspondants. Enfin, les adduits de type Ugi ont été mis à profit pour développer une nouvelle réaction palladocatalysée d'ouverture d'aminocyclopropanes. Cette ouverture conduit à l'accès rapide de produits hétérocycliques dont des tétracycles complexes suite à une réaction tandem impliquant un couplagede Heck.

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Baumgarten, Lars. "Gesteinsmechanische Versuche und petrophysikalische Untersuchungen – Laborergebnisse und numerische Simulationen." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2016. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-202612.

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Dreiaxiale Druckprüfungen können als Einstufenversuche, als Mehrstufenversuche oder als Versuche mit kontinuierlichen Bruchzuständen ausgeführt werden. Bei der Anwendung der Mehrstufentechnik ergeben sich insbesondere Fragestellungen hinsichtlich der richtigen Wahl des Umschaltpunktes und des optimalen Verlaufs des Spannungspfades zwischen den einzelnen Versuchsstufen. Fraglich beim Versuch mit kontinuierlichen Bruchzuständen bleibt, ob im Versuchsverlauf tatsächlich Spannungszustände erfasst werden, welche die Höchstfestigkeit des untersuchten Materials repräsentieren. Die Dissertation greift diese Fragestellungen auf, ermöglicht den Einstieg in die beschriebene Thematik und schafft die Voraussetzungen, die zur Lösung der aufgeführten Problemstellungen notwendig sind. Auf der Grundlage einer umfangreichen Datenbasis gesteinsmechanischer und petrophysikalischer Kennwerte wurde ein numerisches Modell entwickelt, welches das Spannungs-Verformungs-, Festigkeits- und Bruchverhalten eines Sandsteins im direkten Zug- und im einaxialen Druckversuch sowie in dreiaxialen Druckprüfungen zufriedenstellend wiedergibt. Das Festigkeitsverhalten des entwickelten Modells wurde in Mehrstufentests mit unterschiedlichen Spannungspfaden analysiert und mit den entsprechenden Laborbefunden verglichen.

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38

Lin, Yu-Hsiang, and 林郁翔. "A Unified Method for Parametric Fault Characterization of Post-Bond TSVs." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/01840795123507689256.

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碩士
國立清華大學
電機工程學系
100
Three-dimensional (3D) integration using through silicon via (TSV) has been widely acknowledged as one future integrated-circuit (IC) technology. A TSV could suffer from two major types of parametric faults – a resistive open fault, or a leakage fault. Unlikely to stuck-at faults, these parametric faults do not destroy the functionality of a TSV completely but degrade its quality or performance. Based on our previous test structure, called VOT (Variable Output Threshold) scheme for delay faults, we propose a unified in-situ characterization flow for both parametric fault types of a post-bond TSV. With this flow, one can easily derive a more insightful assessment of a parametric fault in production test, process monitoring, and diagnosis-driven yield learning. A scalable test infrastructure indicates that the test time is modest at only 17.2 ms for 1024 TSVs and 648.8 ms for 32,768 TSVs when the test clock is running at 10MHz.

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39

Li, Huai-Min, and 李淮珉. "Efficient Post-Bond Test Techniques for 2.5D and 3D Stacked ICs." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/41552400559759789756.

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碩士
國立臺灣科技大學
電機工程系
101
With the rapid advances of semiconductor technology, the complexity of integrated circuits grows significantly. Three-dimensional integration is considered a promising solution to cure the challenges of performance, power consumption, quality, and reliability issues. The feature of 2.5D ICs is that the dies are stacked on a silicon interposer, and the dies communicate with each other by means of TSV-based interconnects and re-Distribution layers (RDL) in the silicon interposer. This paper aims to investigate the efficient post-bond test technique for the 2.5D ICs with silicon interposer. In order to efficiently reuse the functional interconnects as the parallel TAM (test access mechanism) for testing dies, four strategies including the macro-die strategy, the bidirectional path strategy, the hybrid strategy, and the broadcasting strategy. The macro die strategy merges several dies to form a macro die and then connected to other dies to form a daisy chain for testing. The bidirectional path strategy utilizes tri-state buffers to change the direction of the backward path in a daisy chain during testing such that the TAM width can be broadened. The hybrid strategy combines the features of these two methods. For the broadcasting method, test patterns are broadcasted to all dies simultaneously. Experimental results show that the proposed techniques are better than previous works with respect to the success rate, test length, and algorithm complexity.

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40

Chen, Jyun-Hao, and 陳俊豪. "Residual Bond Strength between Post-Installed Rebar and Concrete after Elevated-Temperature." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/63686627516713159152.

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碩士
逢甲大學
土木工程學系
101
Rebar setting technique, a very important civil engineering construction method, is commonly used in concrete construction when there is a need of alteration, extension or reinforcement of the structures. However, the related research is not sufficient, and the information concerning the bond strength between post-installed rebars and concrete after heat or fire damage is very limited. The main objective of this study is to investigate the effect of elevated temperature on bond behavior between post-installed rebars and concrete by means of pull-out tests. The bond strength and failure type under different experimental conditions are compared and discussed in order to better understand the bond behavior after heat and to summarize the significant directions for further study. The experimental results of this study show that the bonding performance of specimens utilized both selected brands of anchorage glues (Mortar I and Mortar II) are quite good. The rebars set by Mortar I displayed higher bond strength than those set by Mortar II after heated to temperature up to 600 oC, and the deviations in between became larger as the heating temperature increased. The rebars set by both anchorage mortars almost completely lost their bond strength at 800 oC due to the severe damage of concrete specimens. Most specimens, using either brands of anchorage mortars, displayed bond failure between the mortar and rebar. From the comparison of the experimental strengths and the predicted strengths calculated by the anchorage design formula, it could be found that the design formula yields in the conservative side if the temperature is not higher than 300 oC since the experimental values are greater than the predicted values. However, if the temperature exceeds 300 oC, the anchorage design formula may not provide adequate strength prediction. Keyword：Rebar Setting, Bond Strength, Elevated-Temperature,Anchorage Mortar

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41

Yang, Wei-Hsuan, and 楊維軒. "Post-Bond Test and Yield-Enhancement Techniques for Logic-DRAM Stacked ICs." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/368xxs.

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碩士
國立中央大學
電機工程學系
103
Three-dimensional (3D) integration technology using through-silicon via (TSV) has been acknowledged as one integrated circuit (IC) design technology. Logic and dynamic random access memory(DRAM) stacked 3D IC is considered as one effective approach for overcoming memory wall. Since logic and DRAM dies may come from different sources, effective test and diagnosis method for TSVs are imperative for the 3D IC integrator. Furthermore, the stacking process may induce defects. Post-bond yield-enhancement techniques for DRAM stacks are needed. In the first part of this thesis, we propose a programmable built-in self-test (BIST) scheme for logic and DRAM stacked 3D ICs. The BIST can generate control signals for the 1149.1-like bboundary scan in the DRAMdies and test patterns for covering the stuck-at and open faults of TSVs between the DRAM dies and the logic die. Also, a diagnosis test algorithm is proposed to locate the positions of stuck-at and open faults. Furthermore, the BIST can generate the test patterns for DRAM dies through the boundary scan in the logic die. The test and diagnosis algorithm needs 4754 clock cycles to locate faults for a four channel 512-bit datawidth wide I/O DRAM. The area of the BIST is only 7359.4 um2 using TSMC 90nm CMOS standard cell library. In the second part of this thesis, a post-bond built-in self-repair (BISR) scheme is proposed to enhance the yield of 3D DRAMs by using inter-channel redundancy. The inter-channel redundancy can increase the utilization of redundancies. Built-in redundancy analysis (BIRA) algorithms are also proposed to allocate the inter-die redundancy. Simulation results show that the proposed interchannel redundancy scheme can achieve 20.3% increment of repair rate at most than a typical redundancy word architecture when the mean value is 6. The area of BISR is 47880 um2 using TSMC 90nm CMOS standard cell library for a 32G-bit DRAM.

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42

Hu, Tai-Chia, and 胡代佳. "Effect of surface characterization on bond strength of adhesives to zirconia post." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/10290796228799070750.

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碩士
中山醫學大學
口腔材料科學研究所
104
Clinically, when the teeth pulp necrosis or inflammation, dentist removes the pulp tissue, after root canal debridement and expand, and then do dense root canal filling, and installing crowns, dental patients to relieve pain and cure the root infection tip region. Lack of teeth will support force after root canal therapy, therefore, additional support was need since the installation root stem crown. The traditional root stem made is metal or glass fibers, zirconia having high light resistance, aesthetics, good biocompatibility and high tearing resistance and other characteristics, showing the X-ray opacity photography help identify recurrent caries. Zirconia ceramic dental prosthesis becoming more common, but the bond between the ceramic and the tooth has not developed an optimal bond program. In our study, use a different brand of zirconia surface-modified produce test pieces. The material properties for evaluation, comparison between the surface morphology and elemental analysis. In our study, the use of different zirconia ceramic discs and cut into a fixed size (10mm x 10mm x 2.5mm) by computer-aided design and manufacturing (CAD/CAM) process, sintered at 1450

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43

Liang-CheLi and 李良哲. "On-Chip 3D-IC Test System Design for Pre-bond, Post-bond, TSV Test and TSV Diagnosis Based on IEEE 1838 Standard." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/fz97xh.

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碩士
國立成功大學
電機工程學系
102
3D-IC uses the Through Silicon Via (TSV) technology to reduce the connection length between each other circuits and enhance I/O bandwidth. It is also suitable to heterogeneous integration for memory, logic and analog circuits. However, due to the stacked structure with many different dies, the 3D-IC test flow is more complex than the 2D-IC. In the current research on test flow of 3D-IC, it can be divided into two main steps, Pre-bond and Post-bond test. The Post-bond test contains the partial stack, TSV and complete stack test. A low-cost and high-quality test mechanism is proposed in this thesis. We integrate the 3D-IC Test Platform to 3D-IC wrapped with the test interface called IEEE std. 1838, and the overall circuits become a 3D-IC Test System. The system just needs the external equipment or computer through 1149.1 signals sends the required test vectors and test data to platform and then it will generate all control signals and finish the 3D-IC test flow to achieve Pre-bond and Post-bond test and diagnosis for 3D-IC. It can significantly reduce the demand for external test equipment and reduce the test cost of 3D-IC chips by this 3D-IC Test System. In order to improve the yield of TSV by N-detection method, we further propose an efficient test framework of TSV under the overall test time no increasing; In addition, we design a graphical user interface (GUI) to help testers to integrate circuits with 3D-IC Test System quickly and controls the test flow of 3D-IC Test Platform. In experimental results, we just use 1149.1 signals to send the test data to platform and then the platform can effectively execute test functions that contain bottom die logic circuit test in Pre-bond test, logic circuit, memory and analog circuit test in Post-bond test, as well as TSV test and diagnosis. Otherwise the platform can test a single TSV tens to tens of thousands times without increasing test time.

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44

Tseng, Chiu-Ping, and 曾秋萍. "The Influential Factor of Taiwan Government Bond Market-Pre and Post Trading Volume Peak." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/41936635068446948574.

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碩士
淡江大學
財務金融學系碩士在職專班
97
The approach of the thesis is a discussion on the factors of the liquidity during the pre and post trading volume peak in Taiwan Government Bond market. Using the trading volume and the term spread is an index to measure liquidity; performing the variables, such as the volume in stock market, bond issuance, and Overnight Repo Rate, works out the fluctuations in liquidity. Lastly, the variables of the pre and post volume peak would be debated by the term spread. According to the result of this study, since the volume of the Taiwan Government Bond market gradually increases, it is a positive correlation between Overnight Repo Rate and the Taiwan Government Bond liquidity. On the other hand, since the one gradually reduces, it is less correlative. Hence the Overnight Repo Rate has less effect on the Taiwan Government Bond liquidity. Point of view on the bond maturity, there is an obvious correlation between the shorter benchmark bonds and liquidity through a huge amount of the bullish market. Even though the volume decreases, it still remains a strong correlation.

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45

林東翰. "Experimental Study on Bond Behavior of Post-Installed Rebar After Exposure to Elevated Temperature." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/91899955177048308987.

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碩士
逢甲大學
土木工程學系
104
The post-installed rebar technique is commonly used in the repair, reinforcement and extension of concrete constructions. Properly installed rebars can provide good anchorage capacities. However, the fire-resisting ability of the anchorage adhesives is poor. Therefore, this study investigates the bond behavior of post-installed rebar after exposure to elevated temperatures by pull-out tests. The specimens were fabricated by implanting #4 rebars into concrete cylinders with the depths of 9 times the rebar diameter (12cm) or 15 times the rebar diameter (20cm). Then the specimens were heated in the oven up to 200°C, 400°C, 500°C or 600°C for 60 minutes. After the specimens had completely cooled down, the pull-out tests were carried out. The experimental results show that the unheated specimens with two different embedment lengths, mostly fail by rebar fracture, have the similar anchorage capacities. No rebar slippage is observed for these specimens. However, the anchorage capacities of the fire-damaged specimens reduce obviously due to the decrease of the embedment length or the increase of the temperature. While the 200°C to 500°C fire-damaged specimens with 12cm embedment length fail by rebar pull-out following concrete crack, most of the 20cm specimens still display rebar fracture failure. When the temperature rises to 600°C, the specimens with 12cm embedment length lose their anchorage capacities and display bond failure since the anchorage adhesive fails to provide proper bond effect. Nevertheless, the 20cm specimens under the same condition still retains about 50% of the unheated anchorage capacity. In addition, it’s further confirmed, by comparisons with previous studies, that increasing the embedment depth of rebars could effectively enhance the capacity and retard the bond slippage of post-installed rebar.

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46

Huang, Li-Ren, and 黃立仁. "Parametric Fault Testing and Performance Characterization of Post-Bond Interposer Wire in 2.5-D ICs." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/72121147359930162068.

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碩士
國立清華大學
電機工程學系
101
3D Integration that includes many dies on a single packaging substrate has been touted as a new trend for future integrated circuits. In addition to System-in-Package (SiP) and TSV-based stacked IC, the interposer-based 3D IC has been recently proposed by companies like TSMC as another cost-effective alternative. With many advantages like lower cost, ease-of-manufacturing, higher yield, etc., it could become an attractive solution for many portable devices that requires lower power, heterogeneous components, and small and thin form factor. However, to make such an interposer-based 3D IC feasible and reliable, numerous challenging issues on design, testing, and diagnosis remain to be resolved. This thesis addresses the testing and characterization of interposer wires in a 2.5-D stacked IC, which is essential for yield learning and silicon debug. The proposed method provides a number of distinctive features beyond previous works on interposer wire testing. First of all, we target not only catastrophic types of faults (such as stuck-at faults or hard bridging faults) but also parametric types of faults (including both resistive open faults and resistive bridging faults between interposer wires). Secondly, our method can also be used to characterize the propagation delay across each fault-free interposer wire.

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47

HSUAN, CHEN PO, and 陳伯軒. "Influence of Edge Distance on the Bond Strength of Post-Installed Rebar After Fire Damage." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/40952551293575829401.

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碩士
逢甲大學
土木工程學系
103
Post-installed rebar setting, a common anchorage technique for rehabilitating and reinforcing the concrete structures, has been widely used on major engineering projects. However, once such retrofit structures catch fire, the anchorage effect is worthy of consideration. At present, the domestic standard for post-installed rebar setting technique is not formulated, and the reference on the reduction of bond strength at high temperature is not sufficient. It is defective in the design and application of the engineering practice. In order to understand the impairment of bond strength due to elevated temperature, this study investigates the edge distance effect on the pullout strength of post-installed rebar specimens. The specimens were prepared by implanting bars into different sizes of concrete cylinders, and heated in a furnace to the selected levels of temperature. Pullout tests were then performed for both the heated and unheated specimens to determine the differences of bond strength. Finally, the data obtained from the pullout tests were compared with the predicted values calculated by the available design approaches to check whether the regular design method is adequate for high temperature environment. The experimental results show that for the specimens with sufficient edge distances of 6cm and 7.5cm, the bond strength after heated to 200°C are higher than those at room temperature, while the bond strength after heated to the same temperature is lower than that at room temperature for the case of insufficient edge distance 3.75cm. Although all specimens after 400°C fire damage display lower bond strength than the specimens at room temperature, it is obvious that the bond strength becomes higher as the edge distance increases. Since the anchorage adhesive has completely lost its bond effect as for the fire temperature of 600°C, larger edge distance doesn’t help to increase the bond strength. From the comparisons of the experimental strength and the predicted strength calculated by the design formula, it could be found that the design formula yield in the conservative side if the temperature is lower than 200°C, but not applicable at the temperature of 400°C. Keyword: Rebar Setting, Bond Strength, Edge Distance, Elevated Temperature, Anchorage Adhesive.

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48

Wang, Zi-Jian, and 王子建. "A Study on the Linkage among Stock, Bond and REIT Returns in Pre-and Post-Financial Crisis Periods." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/29112640727933992976.

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碩士
大葉大學
國際企業管理學系碩士班
101
Understanding the relationship among stock, bond and REITs returns is very important to practicing portfolio manager. Vector autoregressive model and generalized impulse response function are employed in this study to dynamic interdependence among the stock, bond and REITs returns. This study also attempts to examine the difference of relationship in pre-crisis and post-crisis periods. First, our empirical results find that there is signiﬁcant changing dynamic nature of the relationship in these assets as well as increasing relationships during crisis periods. Second, the impulse response function finds that the REITs and stock are positively correlated with bond in the per-crisis but the relation is opposite in the post-crisis. This implies that an understanding of these changes is important for portfolio updating. Finally, no causal relationships between these assets are found on the whole in the pre-subprime crisis periods but the feedback relations are found after the subprime crisis. The evidence suggests that REITs plays a limited role in mixed portfolio of stocks and bonds after the subprime mortgage crisis.

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49

El, Menoufy Adham Mohamed. "Creep Behaviour of Post-Installed Adhesive Anchors under Various Sustained Load Levels and Environmental Exposures." Thesis, 2010. http://hdl.handle.net/10012/5348.

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This thesis describes an experimental study on the long-term creep behaviour of adhesive anchors under sustained tensile loads in combination with different environmental exposures. A comprehensive background and literature review is presented, focusing on various bond stress models for adhesive anchors, factors affecting their bond behavior, and an overview of available testing standards and evaluation criteria. The experimental program comprises of 82 test specimens. The specimens consist of a cylindrical shaped concrete block of 300 mm (12 inch) in diameter and 200mm (8 inch) in depth, with 15M (No. 5) deformed steel bar post-installed to an embedment depth of six times the bar diameter or 125mm (5 inch). Three types of adhesives were used for anchor installation: Type-A a fast setting two component methyl methacrylate adhesive, Type-B a fast setting two part epoxy adhesive, and Type-C a standard set two part epoxy adhesive. The study is divided into four phases. Phase I consists of 27 static pullout tests to determine the yield strength (fy) and the maximum tensile capacity of each anchor system under three exposure conditions. Phase II and Phase III consist of 36 specimens tested under sustained load levels of 40%fy (32kN) and 60%fy (48kN)under normal laboratory conditions (room temperature) and moisture exposure, respectively. Phase IV consists of 9 specimens tested under sustained load with a load level of 40%fy (32kN) with exposure to freeze/thaw cycling. All sustained load tests lasted for a period of at least 90 days. The results of the static pullout testing showed that specimens with epoxy based adhesive exhibited stronger bond strength, forcing the anchor to fail by rupture prior to bond failure. Under sustained load testing, specimens with standard set epoxy based adhesive showed insignificant creep displacement under room conditions, however, when exposed to moisture noticeable creep displacements were recorded. Specimens with both fast setting epoxy and methyl methacrylate based adhesives showed higher creep displacements under environmental exposure (moisture, freeze/thaw) versus those kept at room temperature. Displacement data from creep testing were analysed and projected over a service life span of 50 years for room temperature exposure, and for 10 years for moisture and freeze/thaw exposures. Based on the analysis results, the service life of different anchor systems was estimated. An integrated qualification and testing protocol is proposed for the creep behavior of adhesive anchors under various environmental exposures.

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50

Shrestha, Sheela. "Effect of glow-discharge treatment on the shear bond strength of glass-fiber-reinforced root canal post bonded to composite." 2006. http://proquest.umi.com/pqdweb?did=1136096391&sid=21&Fmt=2&clientId=39334&RQT=309&VName=PQD.

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Thesis (M.S.)--State University of New York at Buffalo, 2006.
Title from PDF title page (viewed on Oct. 06, 2006) Available through UMI ProQuest Digital Dissertations. Thesis adviser: Baier, Robert E. Includes bibliographical references.

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Dissertations / Theses on the topic 'Post-Bond'

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