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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The Role of NSAIDs in Impaired Osseointegration in Dental Implant Prosthodontics

Winnett, Brenton Paul Lauder Coverdale 11 December 2013 (has links)
Objective: To appraise whether adverse events following oral implant placement may be associated with peri-operative use of non-steroidal anti-inflammatory drugs (NSAIDs). Methods: All patients with recorded implant failures between 1979 and 2012 in the Implant Prosthodontics Unit were contacted to solicit additional information about potential peri-operative use of NSAIDs. Results: From a total of 168 patients with 292 implant failures between 1979 and 2012, 122 consented to participate and had intact records. Just over half (56.6%) reported no peri-operative NSAID usage. However, compared to patients who did not use peri-operative NSAIDs, four times as many had complicated medical histories and twice as many patients taking NSAIDs suffered multiple implant failures. Conclusions: Patients with a variety of systemic diseases may be adversely affected by the inhibitory effect of NSAIDs on bone healing. Further prospective clinical studies are warranted to clarify this potential causative relationship in humans.
12

Influência de tratamentos superficiais na resistência de união de reparo em resina a base de silorano: análise após envelhecimento / Influence of surface treatment on band strength of repair resin-based silorane: analysis after aging

Guimarães, Raphaella Mendes 23 December 2011 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-12-05T14:54:14Z No. of bitstreams: 2 Dissertação - Raphaella Mendes Guimarães - 2011.pdf: 11646606 bytes, checksum: 05767b0e186652fc39182ebc611cd207 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Cláudia Bueno (claudiamoura18@gmail.com) on 2014-12-08T11:50:47Z (GMT) No. of bitstreams: 2 Dissertação - Raphaella Mendes Guimarães - 2011.pdf: 11646606 bytes, checksum: 05767b0e186652fc39182ebc611cd207 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-12-08T11:50:47Z (GMT). No. of bitstreams: 2 Dissertação - Raphaella Mendes Guimarães - 2011.pdf: 11646606 bytes, checksum: 05767b0e186652fc39182ebc611cd207 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2011-12-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aim of the present study was to evaluate the influence of different surface treatments on bond strength of repair resin-based silorane through microtensile test. 160 silorane blocks were randomly distributed among 40 experimental groups (n=4) resulting from the interaction of three factors under study: surface treatment, adhesive system and resin used to repair. The blocks were stored for 9 days in deionized water at 37°C prior to surface treatment and repair. Repair was performed, after the use of a bonding agent: (Ad 1) Silorane bond or (Ad 2) Adper Scotchbond, with Filtek P90 (P90) or Filtek Z350 XT (Z350 XT) on one of the 10 treatment protocols: control (C), silane (Si), phosphoric acid (Pa), Pa plus Si (PaSi), hydrofluoric acid (Ha), Ha plus Si (HaSi), sandblasting (S), S plus Si (SSi), diamond bur (Db), Db plus Si (DbSi). Blocks were sectioned into beams and after age by storage for six months, subjected to microtensile testing and subsequent analysis in a stereoscope to define the failure types. Additionally, 10 blocks of Filtek P90 composite resin were made for surface analysis by SEM, after completion of surface treatment. Statistical analysis (Mann-Whitney, Kruskal- Wallis and Dunn tests, α=0.05) was performed. The values were statistically influenced by the type of resin (p<0.001) and by the surface treatment (p<0.0001), but not by the bonding agent (p=0,940). SSi, Ha and HaSi produced similar bond strength values, the greatest. Treating the surface with Db showed the worst values and composite resin P90 generated higher bond strength values than Z350 XT to repair silorane surfaces. / O objetivo deste estudo foi avaliar a influência de diferentes tratamentos superficiais na resistência de união de reparo em resina composta à base de silorano, por meio de ensaio de microtração. Foram aleatoriamente distribuídos 160 blocos de resina composta a base de silorano em 40 grupos experimentais (n=4) resultantes da interação entre 3 fatores em estudo: tratamento superficial, sistema adesivo e resina para realizar o reparo. Os blocos confeccionados foram armazenados durante 9 dias em água deionizada a 37°C previamente à realização do tratamento superficial e reparo. O reparo foi realizado após a aplicação do sistema adesivo silorano da Filtek P90 (Ad 1) ou do sistema adesivo Adper Scotchbond Multi-uso (Ad 2), com a resina composta Filtek P90 (P90) ou Filtek Z350 XT (Z350 XT), em um dos dez diferentes tipos de tratamento superficial: controle (C), silano (Si), ácido fosfórico (Af), Af e Si (AfSi), ácido hidrofluorídrico (Ah), Ah e Si (AhSi), jateamento (J), J e Si (JSi), ranhuras (R), R e Si (RSi). Os blocos foram seccionados em forma de palito, em seguida armazenados por seis meses, e então submetidos ao ensaio de microtração e posterior análise em lupa estereoscópica para definição do padrão de fratura. Adicionalmente, foram confeccionados 10 blocos de resina composta Filtek P90 para análise da superfície em MEV, após a realização dos tratamentos superficiais. Os dados obtidos foram submetidos a análise estatística (Mann-Whitney, Kruskal-Wallis e Dunn, α=0,05). Pôde-se verificar que os valores de resistência de união foram estatisticamente influenciados pelo tipo de resina (p<0.001) e pelos tratamentos superficiais (p<0.0001), porém não houve diferença para os adesivos (p= 0,940). JSi, Ah e AhSi foram semelhantes entre si e apresentaram os maiores valores. O emprego de ranhuras resultou nos piores resultados e a resina P90 proporcionou maiores valores de resistência de união do que a resina Z350 XT para reparo em resina composta a base de silorano.
13

Mechanical properties evaluation of denture base PMMA enhanced with single- walled carbon nanotubes

Scotti, Kevin January 2010 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Recent theoretical and experimental studies, suggest that Carbon nanotubes are 10-100 times higher than the strongest steel at a fraction of the weight. There are two main types of CNTs that can have high structural perfection. Single-walled nanotubes (SWNTs) consist of a single graphite sheet seamlessly wrapped into a cylindrical tube. Multi-walled carbon nanotubes (MWNTs) comprise an array of such nanotubes concentrically nested like rings of a tree trunk. Denture base acrylics have been reinforced with different materials with limited success. No single reinforced material has showed a great statistical difference in mechanical improvement. The goal of this investigation was to study the effects of Single Walled Carbon Nanotubes reinforcement on the mechanical properties of commercially available denture base PMMA. Denture Base material was reinforced with Single-walled Carbon Nanotubes (SWNTs) at dispersion of 0.25 wt % (group 1), 0.50 wt % (group 2), 0.75 wt % (group 3) and 0.0 wt % (group 4, control). Samples from each group were evaluated for microhardness, flexural strength, flexural modulus, and fracture toughness. The samples were tested in two conditions, as manufactured (dry) and after storing at 37 C for 7 days (wet). Data from four experiments was analyzed by ANOVA. All control sample values were in the range of acceptance compared with previous studies. Higher values were obtained for the control groups for flexural strength and modulus compared with the experimental samples. (p < 0.05) There was no statistical difference regarding fracture toughness between control and experimental groups. A statistical difference was observed in Hardness. The experimental group showed higher values under compression.
14

Resistência à fratura de diferentes núcleos de preenchimento com compósitos bulk fill em dentes com extensa destruição coronária /

Oliveira, Carlos Rangel de Moura January 2019 (has links)
Orientador: José Maurício dos Santos Nunes Reis / Resumo: Este estudo objetivou avaliar a resistência máxima e o padrão de fratura de diferentestécnicas para núcleo preenchimento associados a pinos de fibra de vidro em incisivoslaterais inferiores bovinos com extensa destruição coronária. Quarenta dentes forampreparados endodonticamente, divididos aleatoriamente em 4 grupos experimentais(n=10) e um pino de fibra de vidro (Whitepost DC0,5) foi cimentado com LuxaCore Zpara todos os grupos. A confecção dos núcleos de preenchimento foi realizada, apósobtenção de férula cervical de 1,0 mm, com: FOBF-Filtek One Bulk Fill; FZ350- FiltekZ350 XT; FBFF-Filtek Bulk Fill Flow; e LCZ-LuxaCore Z. Coroas totais de zircônia (YTZP) produzidas em CAD/CAM foram cimentadas com RelyX U200. Apósarmazenamento em água destilada a 37°C por 48 h, os corpos-de-prova foramsubmetidos a ciclos térmicos (10.000 ciclos, 5-55ºC, banhos de 30s) e, posteriormente,ao ensaio mecânico de resistência à fratura por força compressiva aplicada (1,0mm/min) em 135º ao longo eixo do dente em máquina eletromecânica (EMIC DL2000).A força máxima suportada por cada espécime foi registrada em Newton. O modo defratura foi classificado por meio de análise em lupa estereomicroscópica (30X). Osdados de resistência à fratura foram analisados pelo teste não paramétrico de KruskalWallis, seguido pelo post-hoc teste de Dunn. Os dados dos padrões de fratura foramanalisados pelo teste exato de Fisher (α=0,05). Não foram observadas diferençassignificativas (p>0... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed to evaluate the ultimate fracture strength and failure modes of different core techniques associated with intraradicular fiberpost in bovine mandibular lateral incisors with extensive coronary destruction. Forty teeth were prepared endodontically, randomly divided into 4 experimental groups (n=10) and a fiberpost (Whitepost DC0.5) was cemented with LuxaCore Z for all groups. The core was confeccioned, after obtaining a 1.0 mm cervical ferrule, with: FOBF-Filtek One Bulk Fill; FZ350- Filtek Z350 XT; FBFF-Filtek Bulk Fill Flow; and LCZ-LuxaCore Z. Total zirconia crowns (Y-TZP) produced by CAD/CAM were cemented with RelyX U200. After storage in distilled water at 37ºC for 48 h, the specimens were submitted to thermal cycling (10,000 cycles, 5- 55ºC, 30 s dwell time) and, afterwards, to the mechanical test of compressive strength fracture (1.0 mm / min) at 135º along the tooth axis in electromechanical machine (EMIC DL2000). The ultimate load supported by each specimen was recorded in Newton. The fracture mode was classified by means of stereomicroscopic loupe analysis (30X). The fracture strength data were analyzed by the non-parametric Kruskal-Wallis test, followed by the post-hoc Dunn test. The data of the fracture modes were analyzed by Fisher's exact test (α=0.05). No significant differences (p>0.05) were observed among the FOBF, FZ350 and FBFF groups (mean ranks= 20.30, 12.20 and 23.20, respectively). LCZ (mean rank= 26.30) produced similar results to those... (Complete abstract click electronic access below) / Mestre
15

Oligodontia and ectodermal dysplasia on signs, symptoms, genetics and outcomes of dental treatment /

Bergendal, Birgitta, January 2010 (has links)
Diss. (sammanfattning) Umeå : Umeå universitet, 2010. / Härtill 4 uppsatser.
16

Incidência de fratura radicular em dentes submetidos à terapia endodôntica e restaurados com pinos de fibra ou pinos metálicos : revisão sistemática e metanálise

Figueiredo, Fabricio Eneas Diniz de 26 January 2015 (has links)
Endodontically treated teeth have commonly lost most of their coronal structure. In order to restore them, an intrarradicular retainer is required to improve the restorations retention. Event though they have a proper clinical performance, their use has been related to failures such as root fractures. The aim of this systematic review was to analyze the outcome of clinical trials and cohort studies evaluating the post-retained restorations regarding the incidence rate of root fractures. The tested hypothesis was that the incidence rate related to the use of metal posts is higher than that of fiber posts. A search for clinical studies reporting the incidence of root fractures of restorations retained with fiber-reinforced composite posts or metal posts of endodontically treated teeth with more than 5-year of follow-up was conducted from inception to January 2014. Seven randomized clinical trials and 7 cohort studies were included. The overall incidence rate of root fractures was 5.13 (95% CI, 4.05-6.21) per 1000 posts-year. An almost 2-fold increase in the incidence rate of root fractures for prefabricated metal posts and carbon fiber posts compared with cast metal posts and glass fiber posts was observed, respectively. The pooled survival rate was 90% (95% CI, 85.5-93.3) for metal-based posts and 83.9% (95%, CI 67.6-92.8) for fiber-reinforced posts. The results of this study do not support the indication of fiber-reinforced posts based on a reduction of catastrophic failures. However, this review demonstrated the need for further well-designed clinical studies evaluating intra-radicular retainers. / Dentes submetidos à tratamento endodôntico geralmente apresentam grande destruição coronária. Para restaurá-los, o uso de retentor intrarradicular se faz necessário para melhorar a retenção da restauração. Apesar do sucesso clínico, falhas catastróficas têm sido atribuídas ao seu uso. O objetivo desta revisão sistemática foi analisar o resultado de ensaios clínicos e estudos de coorte que reportam a taxa de incidência de fraturas radiculares associadas ao uso de pinos intrarradiculares. A hipótese foi que dentes restaurados com uso de pinos metálicos apresentam maior incidência de fraturas radiculares que aqueles restaurados com de pino de fibra. Até Janeiro de 2014, buscou-se por estudos clínicos que avaliaram o índice de fraturas radiculares relacionadas ao uso de retentores intrarradiculares metálicos ou de fibra de vidro em dentes submetidos à tratamento endodôntico com tempo de acompanhamento superior a cinco anos. Sete ensaios clínicos randomizados e sete estudos de coorte foram incluídos. A taxa de sobrevivência estimada foi de 90% (95% intervalo de confiança {IC} 85,5 – 93,3) para pinos metálicos e 83,9% (IC 95%, 67,6 – 92,8) para pinos de fibra. A taxa de incidência total de fraturas radiculares (falhas catastróficas) foi similar entre pinos metálicos e de fibra. Pinos metálicos pré-fabricados e pinos de fibra de carbono apresentaram taxa de incidência de fraturas radiculares duas vezes maior quando comparadas com núcleos metálicos fundidos e pinos de fibra de vidro respectivamente. Os resultados deste estudo não demonstraram diferenças significantes na taxa de incidência de fraturas radiculares entre pinos metálicos e de fibra. Entretanto, os estudos incluídos nesta revisão apresentaram alto risco de viés, portanto, há necessidade de se realizarem estudos clínicos bem delineados para confirmar estes achados.
17

Brilho, rugosidade e integridade da superfície de resinas compostas = efeito do polimento e escovação / Bright, roughness and integrity of the surface of composite resin : effect of polishing and brushing

Carrilho Neto, Antonio, 1962- 18 August 2018 (has links)
Orientadores: Lourenço Correr Sobrinho, Simonides Consani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-18T20:46:54Z (GMT). No. of bitstreams: 1 CarrilhoNeto_Antonio_D.pdf: 8464064 bytes, checksum: 16996840d4c6ac4cececfc832c5f7e73 (MD5) Previous issue date: 2011 / Resumo: O objetivo neste estudo foi avaliar a influência de sistemas de polimento e escovação mecânica simulada, sobre o brilho, rugosidade e integridade da superfície de materiais restauradores estéticos. Quatro compósitos foram avaliados: Filtek Z350 XT - 3M ESPE, Charisma Opal - Heraeus Kulzer, Amelogen Plus - Ultradent, Tetric N-Ceram - Ivocler Vivadent. Vinte amostras cilíndricas padronizadas foram obtidas para cada material e separadas aleatoriamente em 2 grupos (n=10), sendo que cada grupo foi submetido a um dos dois procedimentos de polimento (Sof-Lex - 3M ESPE e PoGo - Dentsply Caulk). Em seguida, todas as amostras foram submetidas às avaliações de brilho, mensurado com medidor (Zehntner ZGM 1120 Glossmeter) e a rugosidade com rugosímetro (Surfcorder SE1700 - Kosaka Lab) e submetidas a 30000 ciclos mecânicos de escovação simulada, utilizando solução de dentifrício (Colgate) e água destilada. Na seqüência da escovação, as mensurações de brilho e rugosidade foram repetidas. Em seguida, as amostras foram submetidas aos procedimentos de polimento, seguidos das avaliações de brilho e rugosidade. Os dados foram submetidos à ANOVA para medidas repetidas e teste de Tukey (p?0,05). Adicionalmente, amostras iniciais, escovadas e polidas foram examinadas em microscopia eletrônica de varredura (5600LV - Jeol) para avaliação qualitativa da integridade da superfície. Com base nos resultados de Rugosidade Média encontrados após a escovação simulada, pode-se concluir que a resina nanoparticulada apresentou menor rugosidade pela escovação mecânica (0,275 ?m) e maior brilho por ambos os métodos de polimento (PoGo 71,78 GU e Sof-Lex 70,64 GU); A escovação mecânica aumentou os valores médios de rugosidade e diminuiu o brilho dos compósitos; Os sistemas de polimento não foram capazes de recuperar a lisura quando comparados à fase inicial; Ambos os sistemas de polimento melhoraram o brilho deixado pela escovação, com exceção do compósito Amelogem Plus. Com base nas análises das imagens do MEV, foi possível observar que o sistema de polimento de múltiplos passos (Sof-Lex - 3M ESPE) favorece a presença de sulcos profundos / Abstract: The purpose in this study was to evaluate the influence of polishing systems and simulated mechanical toothbrushing, about gloss, rugosity and integrity on surfaces of esthetic restorative materials. Four composites were evaluated: Filtek Z350 Supreme (tem que colocar "supreme" no ingles?) XT (3M ESPE), Charisma Opal (Heraeus Kulzer), Amelogen Plus (Ultradent) and Tetric NCeram (Ivoclair Vivadent). Twenty cylindrical standardized specimens, for each material, were fabricated and ramdomly divided in two groups (n=10), each group being submitted to one of the two polishing protocols (Sof-Lex - 3M ESPE; POGO Dentsply Caulk). After, all specimens were submitted to the following evaluations, surface optical gloss was determined using a glossmeter (ZGM 1120 Glossmeter - Zehntner) and surface roughness was measured with a surface profilometer ( Surfcorder SE 1700 -Kosaka Lab.), and specimens were submitted to 30,000 mechanical simulated brushing cycles, with a dentifrice-water slurry (Colgate) and distilled water. Following brushing, gloss and roughness measurements were evaluated again. Then, specimens were submitted to the polishing process, followed by gloss and roughness evaluations. Data were submitted to ANOVA statistical analysis for repeated measures and Tukey Test (p?0,05). Additionally, initial specimens, brushed and polished, were evaluated under scanning electron microscopy (5600 LV-Jeol) for qualitative surface integrity. Based on the middle rugosity results found after simulated brushing, could be concluded that nanometric composites showed lower rugosity when submitted to mechanical simulated toothbrushing (0,275 ?m) and higher gloss with both polishing protocols (PoGo 71,78 GU e Sof-Lex 70,64 GU); mechanical tooth brushing increased the rugosity middle values and decreased the composite gloss; The polishing systems were not capable to recover smoothness when compared to the initial phase (polyester matrix); both polishing system improved gloss given by brushing, exceptionally for the Amelogen Plus composite. Based on MEV image analysis, was observed that the multiple step polishing system (Sof-Lex - 3M ESPE) favors the presence o deep sulcus / Doutorado / Materiais Dentarios / Doutor em Materiais Dentários
18

Effects of Various Thicknesses on Load to Fracture of Posterior CAD/CAM Lithium Disilicate Glass Ceramic Crowns Subjected to Cyclic Fatigue

Al-Angari, Nadia January 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Background: New glass ceramics and Computer-Aided Design/Computer Assisted Manufacture (CAD/CAM) have become common aspects of modern dentistry. The use of posterior ceramic crowns with a high level of esthetics, fabricated using the CAD/CAM technology is a current treatment modality. Several materials have been used to fabricate these crowns, including lithium disilicate glass-ceramics, which have not been fully investigated in the literature. Objective: to investigate the load to fracture of lithium disilicate glass ceramic posterior crowns fabricated by CAD/CAM technology with different material thicknesses adhesively cemented on epoxy resin. Methods: Four groups of different ceramic thicknesses (0.5 mm, 1 mm, 1.5 mm, and 2 mm) were fabricated by milling CAD/CAM lithium disilicate IPS emax CAD blocks. A total of 68 posterior crowns were surface treated and luted with a resin adhesive cement on an epoxy resin model. Samples were fatigued then loaded to fracture using a universal testing machine to test the fracture strength. Statistical comparisons between various crown thicknesses were performed using one-way ANOVA followed by Fisher's Protected Least Significant Differences. Results: There was a significant difference in the load-to-fracture (N) value for all comparisons of the four thickness groups (p < 0.0001), except 2 mm vs. 1.5 mm (p = 0.325). The mean load-to-fracture (N) was significantly higher for 2 mm than for 1 mm or 0.5 mm. Additionally, the mean load-to-fracture was significantly higher for 1.5 mm than for 1 mm or 0.5 mm. Furthermore, the mean load-to-fracture was significantly higher for 1 mm than for 0.5 mm. Conclusion: Within the limitation of this study, it is advisable for clinical applications to consider a crown thickness of 1.5 mm or greater of milled lithium disilicate for posterior single teeth.
19

Efeito da infiltração de sílica pelo método sol-gel na resistência à flexão de bicamadas de porcelana e Y-TZP / Effect of silica infiltration by sol-gel method on the flexural strength of porcelain and Y-TZP bilayers

Reis, Ana Flávia Nunes [UNESP] 15 December 2015 (has links)
Submitted by ANA FLÁVIA NUNES E REIS null (dra-anaflavia@uol.com.br) on 2016-01-26T19:16:31Z No. of bitstreams: 1 merged (4).pdf: 4937949 bytes, checksum: c052666784bd930ac4748e41040c73bd (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-01-28T13:31:20Z (GMT) No. of bitstreams: 1 reis_afn_me_sjc.pdf: 4937949 bytes, checksum: c052666784bd930ac4748e41040c73bd (MD5) / Made available in DSpace on 2016-01-28T13:31:20Z (GMT). No. of bitstreams: 1 reis_afn_me_sjc.pdf: 4937949 bytes, checksum: c052666784bd930ac4748e41040c73bd (MD5) Previous issue date: 2015-12-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste trabalho foi infiltrar sílica em uma cerâmica Y-TZP, avaliar seu efeito na resistência à flexão Biaxial, e na união com a porcelana feldspática. Para a análise da resistência à flexão foram confeccionados 180 discos de zircônia, 120 de 0,5mm e 60 com 1,2mm discos (14 mm de diâmetro). 90 discos foram infiltrados com sílica pelo método sol-gel em temperatura ambiente (n = 30). A espessura do disco foi de 1,2 mm para os espécimes controle (espécime sem porcelana, n = 30). O recobrimento por porcelana feldspática foi de duas espessuras (0,5mm e 1 mm) sobre a zircônia que tinha 0,5 mm. Os espécimes com porcelana foram polidos com lixas de carbeto de silício (SiC) de granulação # 400, 600, 800 e 1200. Obtivemos 6 grupos: dois monolíticos (ZR- Zircônia Monolítica sem infiltração e ZRI- Zircônia Monolítica Infiltrada) (controle) e quatro estratificados: ZRF 1,0 (0,5mm Zircônia coberta com 0,5 mm porcelana), ZRIF 1,0 (0,5 mm Zircônia infiltrada coberta com 0,5 mm de porcelana), ZRF 1,5 (0,5 mm Zircônia infiltrada coberta com 1,0 mm de porcelana) ZRIF 1,5- Zircônia infiltrada (0,5 mm Zircônia infiltrada coberta com 1,0 mm de porcelana). Após o ensaio de flexão biaxial em meio aquoso, foram determinados o módulo de Weibull (m) e resistência característica (σθ). Os fragmentos foram analisados em EDS, MEV, DRX e FTIR. A Dureza (H) e tenacidade a fratura foram analisadas pela nanoindentação, já o módulo elástico (E) por duas técnicas, nanoindentação e por impulso, e para avaliar a adesão entre a zircônia e a porcelana foi aplicado o Teste de Scratch. Foram modeladas 7 condições experimentais e analisados pelo método por elementos finitos. A zircônia monolítica infiltrada mostrou uma estrutura com grãos arredondados envoltos em uma matriz de sílica, e a presença de zircônia cúbica e tetragonal. O DRX revelou a formação de ZrSiO4 nos grupos infiltrados. Os grupos monolíticos apresentaram módulos de Weibull superiores aos dos grupos com porcelana. Com a análise (AEF) não houve diferença entre os grupos com a mesma espessura, já para o grupo recoberto com 0,5 mm de porcelana, os valores de tração e compressão foram maiores. A cerâmica infiltrada apresentou microestrutura diferente, e a adesão da porcelana à zircônia não-infiltrada foi superior à da zircônia infiltrada. / The objective was to infiltrate silica in a Y- TZP ceramics, evaluate its effect on resistance biaxial strenght, and the union with feldspathic porcelain. For the analysis of flexural strength were prepared zirconia discs 180, 120 and 60 of 0.5 mm to 1.2 mm disks (14 mm diameter). 90 discs were infiltrated with silica by the sol-gel method at room temperature (n = 30). The thickness of the disk was 1.2 mm for the samples control (no porcelain specimen, n = 30). The coating was feldspathic porcelain by two thicknesses (0.5 mm and 1 mm) of zirconia, which had 0.5 mm. Specimens with porcelain were polished with sandpaper silicon carbide (SiC) granulation # 400, 600, 800 and 1200. We obtained six groups: two monolithic (Zr-Zirconia Monolithic without infiltration and ZRI- Zirconia monolithic Infiltrated) (control) and four laminated ZRF 1.0 (0.5 mm zirconia covered with 0.5 mm porcelain), ZRIF 1.0 (0.5 mm infiltrated zirconia covered with 0.5 mm of porcelain), ZRF 1.5 (0.5 mm infiltrated zirconia covered with 1.0 mm of porcelain) ZRIF 1,5-infiltrated Zirconia (0.5 mm infiltrated zirconia covered with 1.0 mm of porcelain). After the biaxial bending test in an aqueous medium were determined Weibull modulus (m) and the characteristic strength (σθ). The fragments were analyzed by EDS, SEM, XRD and FTIR. The hardness (H) and fracture toughness were analyzed by nanoindentation, since the elastic modulus (E) by two techniques, nanoindentation and on impulse, and to evaluate the adhesion between the zirconia and porcelain was applied Scratch Test. 7 experimental conditions were modeled and analyzed by the finite element method. The infiltrated zirconia showed a monolithic structure with rounded grain wrapped in a silica matrix, and the presence of cubic and tetragonal zirconia. The XRD showed the formation of ZrSiO4 infiltrates in groups. The monolithic modules Weibull groups showed superior to porcelain groups. With the analysis (FEA) there was no difference between the groups with the same thickness, for now the group covered with 0.5 mm of porcelain, the tensile and compressive values were higher. The infiltrated ceramic showed different microstructure, and the accession of porcelain to non- infiltrated zirconia was higher than the infiltrated zirconia.

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