Orientador: Marcelo Ferraz Mesquita / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-09T19:25:40Z (GMT). No. of bitstreams: 1 Oliveira_LucianaValadares_D.pdf: 36824583 bytes, checksum: 7a4d2a0d063c3cd9180327ea1a830f60 (MD5) Previous issue date: 2007 / Resumo: As distorções oriundas das técnicas de aplicação dos revestimentos estéticos sobre infraestruturas metálicas de próteses fixas podem resultar em margens cervicais desadaptadas. Este trabalho avaliou o efeito do tipo de revestimento estético, da simulação dos ciclos de cocção da porcelana e da eletroerosão sobre o desajuste de infra-estruturas implantossuportadas. Foi utilizada uma matriz metálica simulando um arco mandibular, contendo 5 pilares intermediários do tipo Microunit (Conexão Sistema de Próteses, Brasil). Sobre essa matriz, foram enceradas 40 infra-estruturas, fundidas em liga de CoCr (Remanium 2000, Alemanha). Para cada infra-estrutura, foi confeccionado um index, parafusando-se 5 réplicas em cada uma das infra-estruturas. Esse conjunto foi posicionado em gesso pedra especial com auxílio de delineador, antes da aplicação dos revestimentos estéticos, para avaliar o desajuste provocado apenas pela fase de aplicação dos revestimentos estéticos e ciclo de cocção da porcelana. As infra-estruturas foram separadas aleatoriamente: G1: resina acrílica termopolimerizável (Clássico, Clássico, Brasil); G2: resina fotopolimerizável (Versyo.com, Heraeus Kulzer, Brasil); G3: porcelana (Carmen, Dentaurum, Alemanha); G4: simulação dos ciclos de cocção da porcelana. Antes da aplicação dos revestimentos estéticos, foi realizada a avaliação do desajuste marginal sobre o index, após aperto de 10 Ncm em um único parafuso, correspondente ao implante A. Através desse procedimento, verificou-se a adaptação dos componentes C e E. O procedimento foi repetido no outro implante mais distal (E), para mensuração nos implantes A e C. As leituras foram realizadas utilizando microscópio mensurador (STN ¿ Olympus Optical, Japão). Procedeu-se o processo de eletroerosão (Tel Med Technologies, EUA), e novamente avaliação do desajuste marginal. Os resultados obtidos foram submetidos à Análise de Variância e teste de Tukey (p<0,05). Os valores de desajuste marginal das infra-estruturas antes da aplicação dos revestimentos estéticos não apresentaram diferença estatística significante entre si: G1: 56,97 µm (± 16,86); G2: 43,27 µm (± 16,49); G3: 49,26 µm (± 17,11); G4: 40,66 µm (+ 10,85). A aplicação dos revestimentos estéticos e simulação dos ciclos de cocção da porcelana aumentaram significantemente os valores médios de desajuste marginal para todos os grupos: G1: 170,01 µm (±53,98); G2: 72,32 µm (±27,49); G3: 164,84 µm (±27,67); e G4: 86,28 µm (±20,01). Os grupos G1 e G3 não apresentaram diferença estatisticamente significante entre si, mas apresentaram diferença quando comparados aos G2 e G4. Após eletroerosão, as médias de desajuste marginal apresentaram valores significamente menores para os grupos: Gl: 108, 54 µm (±40,75); G3: 109,61 µm (±24,42); e G4: 59,63 µm (±22,13). A média de desajuste marginal para o grupo de resina fotopolimerizável não apresentou diferença estatística significante: G2: 49,70 µm (±16,65). Como observado anteriormente, os grupos G1 e G3 não apresentaram diferença estatística significante, mas ambos apresentaram diferença dos grupos G2 e G4. Conclui-se que os revestimentos estéticos em resina acrílica e porcelana produzem os maiores valores de desajuste marginal para próteses implantossuportadas, enquanto a resina fotopolimerizável, os menores. A aplicação de porcelana resultou em maiores valores de desajuste marginal que apenas a simulação dos ciclos de cocção. A eletroerosão foi eficaz na redução dos desajustes marginais até os limites considerados clinicamente aceitáveis / Abstract: The demand for a passive fit of frameworks for osseointegrated endousseous implants abutments is well known, because the tightening of an inaccurate framework to the abutments can transmit stress to the bone-metal interface. The purpose of the present study was to evaluate the influence of the veneering application and porcelain firing cycle on the misfit level of implant-supported frameworks. Forty Co-Cr (Remanium 2000, Dentaurum, Germany) alloy frameworks were fabricated from a metallic index containing 5 Branemark type multi unit abutments. Analogs of the abutments were positioned to the framework, to construct an index for each framework. This index allowed the observation of the marginal gaps caused by the application of the veneering material. The frameworks were grouped (n=10): 1) heat acrylic resin (Clássico, Clássico, São Paulo, Brazil); 2) light polymerized resin (Versyo.com, Heraeus Kulzer, Brazil); 3) porcelain application (Carmen, Dentaurum, Germany); 4) simulation of porcelain firing cycle. Marginal refinement with spark erosion was conducted on specific equipment (Tel Med Technologies, U.S.A.). The marginal gap was obtained before and after the veneering materials and the spark erosion procedure, following the single screw test protocol (using a tightening force of 10 Ncm). A traveling microscope (STN ¿ Olympus Optical Co. Ltd Japan (120X) was used, tightening 10N in the titanium screw of the extremity distal implant, measuring the gaps at the central and distal implants. Data were subject Analysis of Variance followed by Tukey test (5%). Marginal gap mean values of the frameworks before the veneering application were not significantly different: G1: 56.97(± 16.86); G2: 43.27(± 16.49); G3: 49.26(± 17.11); G4: 40.66(± 10.85). The application veneering materials and the simulation of porcelain firing cycle increased significantly the misfit mean values of all groups: G1: 170.01 µm (±53.98); G2: 72.32 µm (+±27.49); G3: 164.84 µm (±27.67); e G4: 86.28 µm (±20.01). There were no significant differences between G1 and G3, but they were significantly different from both G2 and G3. After the spark erosion process, marginal gap mean values decreased significantly for the following groups: G1: 108. 54 µm (±40.75); G3: 109.61 µm (±24.42); and G4: 59.63 µm (±22.13). The light curing group decreased the marginal gap mean values, but not significantly after the spark erosion procedure: G2: 49.70 µm (±16.65). As occurred after the application of veneering materials, G1 and G3 groups did not show significant difference, but they both were significantly different from G2 and G4 groups. It can be concluded that heat cured acrylic resin and porcelain produced the highest mean values of marginal gaps, while light cured acrylic resin, the lowest. The application of porcelain produced higher misfit values than the simulation of porcelain firing cycles only. The spark erosion procedure was efficacious in reducing the frameworks marginal gaps to the levels clinically accepted for all groups evaluated. / Doutorado / Protese Dental / Doutor em Clínica Odontológica

O objetivo deste trabalho foi avaliar a influência de diferentes aminas terciárias no grau de conversão, na contração de polimerização, na taxa de contração, na microdureza Knoop, na estabilidade de cor e na transmitância de luz de resinas experimentais, contendo, em peso, BisGMA e TEGDMA (3:1), 0,25% de canforquinona (CQ) e 1% de amina (DMAEMA, CEMA, DMPT, DEPT ou DABE). A influência de diferentes protocolos de fotoativação também foi investigada. O grau de conversão foi avaliado através de FTIR-ATR e a contração pelo método do disco aderido. A partir da diferenciação numérica dos dados de contração em relação ao tempo, obteve-se a taxa de contração de polimerização. A estabilidade de cor e a transmitância foram avaliadas em diferentes períodos de envelhecimento artificial. Os resultados foram avaliados pelos testes de ANOVA, Tukey e T3 de Dunnett (&#945; = 0,05). As propriedades estudadas variaram em função da amina. O grau de conversão e a contração de polimerização variaram na sequência: CQ < DEPT < DMPT &#8804; CEMA &#8776; DABE < DMAEMA. O grau de conversão e a contração também foram influenciados pelo protocolo de fotoativação, sendo observadas correlações positivas entre o grau de conversão e a contração e entre o grau de conversão e a taxa de contração. A cor variou na sequência: DMAEMA < DEPT < DMPT < CEMA < DABE. A transmitância variou na sequência: DEPT &#8776; DABE < DABE &#8776; DMPT &#8776; CEMA < DMPT &#8776; CEMA &#8776; DMAEMA, sendo mais evidente para o comprimento de onda de 400nm. Não foram observadas correlações entre o grau de conversão e as propriedades ópticas. A resina contendo DMAEMA apresentou maior grau de conversão, contração, taxa de contração e dureza, além de melhor estabilidade nas propriedades ópticas. / The aim of this work was to evaluate de influence of different tertiary amines on degree of conversion (DC), shrinkage-strain, shrinkage-strain-rate, Knoop microhardness, and colour and transmittance stabilities of experimental resins containing BisGMA / TEGDMA (3:1 wt), 0,25wt% camphorquinone, 1wt% amine (DMAEMA, CEMA, DMPT, or DABE). Different light-curing protocols were also evaluated. DC was evaluated with FTIR-ATR and shrinkage-strain with the bonded-disc method. Shrinkage-strain-rate data were obtained from numerical differentiation of shrinkage-strain data with respect to time. Colour stability and transmittance were evaluated during different periods of artificial aging, according to ISO 7491:2000. Results were evaluated with ANOVA, Tukey and Dunnetts T3 tests (&#945; = 0.05). The studied properties varied according to amines. DC and shrinkage-strain were maximum at the sequence: CQ < DEPT < DMPT &#8804; CEMA &#8776; DABE < DMAEMA. Both DC and shrinkage were also influenced by the curing protocol, with positive correlations between DC and shrinkage-strain and DC and shrinkage-strain-rate. Colour varied in the sequence: DMAEMA < DEPT < DMPT < CEMA < DABE. Transmittance varied in the sequence: DEPT &#8776; DABE < DABE &#8776; DMPT &#8776; CEMA < DMPT &#8776; CEMA &#8776; DMAEMA, being more evident at the wavelength of 400nm. No correlations between DC and optical properties were observed. The resin containing DMAEMA showed higher DC, shrinkage-strain, shrinkage-strain-rate and microhardness, in addition with better optical properties.

O objetivo deste trabalho foi avaliar a influência de diferentes aminas terciárias no grau de conversão, na contração de polimerização, na taxa de contração, na microdureza Knoop, na estabilidade de cor e na transmitância de luz de resinas experimentais, contendo, em peso, BisGMA e TEGDMA (3:1), 0,25% de canforquinona (CQ) e 1% de amina (DMAEMA, CEMA, DMPT, DEPT ou DABE). A influência de diferentes protocolos de fotoativação também foi investigada. O grau de conversão foi avaliado através de FTIR-ATR e a contração pelo método do disco aderido. A partir da diferenciação numérica dos dados de contração em relação ao tempo, obteve-se a taxa de contração de polimerização. A estabilidade de cor e a transmitância foram avaliadas em diferentes períodos de envelhecimento artificial. Os resultados foram avaliados pelos testes de ANOVA, Tukey e T3 de Dunnett (&#945; = 0,05). As propriedades estudadas variaram em função da amina. O grau de conversão e a contração de polimerização variaram na sequência: CQ < DEPT < DMPT &#8804; CEMA &#8776; DABE < DMAEMA. O grau de conversão e a contração também foram influenciados pelo protocolo de fotoativação, sendo observadas correlações positivas entre o grau de conversão e a contração e entre o grau de conversão e a taxa de contração. A cor variou na sequência: DMAEMA < DEPT < DMPT < CEMA < DABE. A transmitância variou na sequência: DEPT &#8776; DABE < DABE &#8776; DMPT &#8776; CEMA < DMPT &#8776; CEMA &#8776; DMAEMA, sendo mais evidente para o comprimento de onda de 400nm. Não foram observadas correlações entre o grau de conversão e as propriedades ópticas. A resina contendo DMAEMA apresentou maior grau de conversão, contração, taxa de contração e dureza, além de melhor estabilidade nas propriedades ópticas. / The aim of this work was to evaluate de influence of different tertiary amines on degree of conversion (DC), shrinkage-strain, shrinkage-strain-rate, Knoop microhardness, and colour and transmittance stabilities of experimental resins containing BisGMA / TEGDMA (3:1 wt), 0,25wt% camphorquinone, 1wt% amine (DMAEMA, CEMA, DMPT, or DABE). Different light-curing protocols were also evaluated. DC was evaluated with FTIR-ATR and shrinkage-strain with the bonded-disc method. Shrinkage-strain-rate data were obtained from numerical differentiation of shrinkage-strain data with respect to time. Colour stability and transmittance were evaluated during different periods of artificial aging, according to ISO 7491:2000. Results were evaluated with ANOVA, Tukey and Dunnetts T3 tests (&#945; = 0.05). The studied properties varied according to amines. DC and shrinkage-strain were maximum at the sequence: CQ < DEPT < DMPT &#8804; CEMA &#8776; DABE < DMAEMA. Both DC and shrinkage were also influenced by the curing protocol, with positive correlations between DC and shrinkage-strain and DC and shrinkage-strain-rate. Colour varied in the sequence: DMAEMA < DEPT < DMPT < CEMA < DABE. Transmittance varied in the sequence: DEPT &#8776; DABE < DABE &#8776; DMPT &#8776; CEMA < DMPT &#8776; CEMA &#8776; DMAEMA, being more evident at the wavelength of 400nm. No correlations between DC and optical properties were observed. The resin containing DMAEMA showed higher DC, shrinkage-strain, shrinkage-strain-rate and microhardness, in addition with better optical properties.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-01-15T12:14:11Z No. of bitstreams: 1 liviasalgado.pdf: 1200969 bytes, checksum: 244d1e72c0eb8f8d2b1211681283ab46 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-01-25T17:38:49Z (GMT) No. of bitstreams: 1 liviasalgado.pdf: 1200969 bytes, checksum: 244d1e72c0eb8f8d2b1211681283ab46 (MD5) / Made available in DSpace on 2016-01-25T17:38:49Z (GMT). No. of bitstreams: 1 liviasalgado.pdf: 1200969 bytes, checksum: 244d1e72c0eb8f8d2b1211681283ab46 (MD5) Previous issue date: 2015-04-27 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Avaliou-se a rugosidade das superfícies de duas resinas compostas, antes e após a sua imersão em solução aquosa com diferentes pH e solução enzimática. Para a confecção dos 60 corpos de prova, 30 para cada resina composta, utilizou-se uma matriz de acrílico com 5mm de diâmetro e 2mm de espessura, sobre uma tira de poliéster posicionada em uma placa de vidro estéril que foram preenchidas com as resinas compostas Filtek Z350 (3M ESPE) e Empress Direct (Ivoclar-Vivadent), em um único incremento e sobre esta foi colocada outra tira de poliéster e procedeu a fotopolimerização por 40s. Os corpos de prova foram divididos 06 grupos (n=10) de acordo com a solução empregada: água deionizada (Grupos ZA e EA); hidróxido de sódio com pH 13.2 (Grupos ZNa e ENa) e solução enzimática de colesterol esterase (Grupos ZE e EE). Para dar acabamento utilizou-se uma sequência decrescente de granulação de lixas d’água: 600, 1000, 1200, 1500 e 2000 e para o polimento, suspensões de alumina (Arotec, São Paulo, SP, Brasi): 1μm, 0,3μm e 0,05μm. Após o polimento foram armazenados em estufa a 37°C durante 7 dias e realizadas 3 medições de cada superfície no rugosímetro e realizada a média e foram imersos individualmente nas soluções por 30 dias e mantidos em estufa a 37°C, a cada 7 dias as soluções eram trocadas. Após 30 dias foram realizadas mais 3 medições da rugosidade das superfícies e realizada a média. Foi realizada ANOVA e o teste de Tukey. A partir dos resultados obtidos conclui-se que as resinas compostas testadas apresentaram degradação hidrolítica apenas na solução aquosa por um período de imersão de 30 dias. / The roughness of the surfaces was evaluated two composites before and after their immersion in aqueous solutions with different pH and the enzyme solution. For producing the 60 test specimens, 30 for each composite was used an acrylic matrix with 5mm in diameter and 2mm thick on a polyester strip placed on a sterile glass plate were filled with the resins Filtek Z350 (3M ESPE) and Empress Direct (Ivoclar Vivadent-) in a single increment and this was placed on another strip of polyester and proceeded to light curing for 40 seconds. The specimens were divided 06 groups (n = 10) according to the used solution: deionized water (ZA Groups and EA); sodium hydroxide at pH 13.2 (ZNA Groups ENA) and enzyme solution of cholesterol esterase (ZE and EE groups). To finish used a descending sequence of sanding granulation water: 600, 1000, 1200, 1500 and 2000 and for polishing alumina suspensions (Arotec, São Paulo, SP, Brasi): 1μm, and 0,3μm 0,05μm. After polishing were stored at 37 ° C for 7 days and 3 measurements carried out on each surface roughness and the carried medium and were immersed in individual solutions and kept for 30 days at 37 ° C every 7 days the solutions were exchanged. After 30 days there were over 3 measurements of surface roughness and made average. ANOVA and Tukey test was performed. From the results obtained it is concluded that the composites tested showed hydrolytic degradation in aqueous solution only for a period of 30 days immersion.

Background: The light-cured resin-based pit and fissure sealants success and longevity are enhanced by sufficient curing. Multiple emission peak Light Emitting Diode Light Curing Units offer a wider range of wavelengths and different levels of irradiances to ensure sufficient curing.The irradiance is considered a main curing factor that can affect the material properties. Purpose: The aim of this study was to assess the effect of different settings of a multiwave LED LCU on the degree of conversion and microhardness of a pit and fissure sealant comparing the irradiance of 1000 mW/cm2 to 1400 mW/cm2 and 3200 mW/cm2 irradiances of the LCU using manufacturer’s guidelines for curing times at 2, 4 and, 6 mm distances. Methods: A multiwave LED light curing unit was evaluated on three different irradiance levels 1000 mW/cm2 (S), 1400 mW/cm2 (H), and 3200 mW/cm2 (X). A total of 90 samples made from the fissure sealant were fabricated and divided into eighteen groups (n=5/group). Samples were cured following manufacturer’s guidelines of curing times for each curing mode at 2, 4, or 6 mm distance between the light tip and top of samples. The DC was measured using (ATR-FTIR) spectroscopy. The KHN test was performed on five different locations of each specimen using a hardness tester (Leco LM247AT, MI, USA, software; Confident V 2.5.2). Results: The top DC for H-8 was significantly higher than S-10 at 2 and 4mm, H-20 DC was significantly lower than S-30 at only 2mm. The bottom DC for H-8 was significantly higher than S-10 at 2mm only, H-20 DC was significantly lower than S-30 at 4 and 6mm only. H-8 KHN at top surface was significantly lower than S-10 at 2mm only, H-20 was significantly lower than S-30 at 2 and 6mm only. H-8 KHN at bottom surface was significantly lower than S-10 at 4 and 6mm but significantly higher at 2mm. H-20 was significantly lower than S-30 at 2mm but significantly higher at 4 and 6mm. The top DC for X-3 was significantly lower than S-10 at all curing distances with no significant difference at all curing distances between X-9 and S-30. The bottom DC for X-3 was significantly higher than S-10 at all curing distances with no significant difference between X-9 and S-30. X-3 KHN at top surface was significantly lower than S-10s at all curing distances. X-9 was significantly lower than S-30 at 6mm only. X-3 KHN at bottom surface was significantly lower than S-10 at 2 and 4mm only with no significant difference at all curing distances between X-9 and S-30. Conclusions: Using a multiwave LED LCU to polymerize Delton Opaque resin-based fissure sealants will result in an optimal DC and KHN values for any irradiance level if the curing distance is kept at 4 mm or less and with at least two cycles of the shortest curing time recommended by the manufacturer. Using a multiwave LED LCU with 1000, 1400 or 3200 mW/cm2 irradiance levels with shortest curing times recommended resulted in unsatisfactory DC and KHN levels. LED LCU with high and extra high irradiance levels (1400 and 3200 mW/cm2) can result in high DC and KHN levels when used adequately. Xtra Power mode (3200 mW/cm2) used on shortest curing time (3 seconds) resulted in significantly lower mechanical properties and for that reason it is not recommended to be used.

Indiana University-Purdue University Indianapolis (IUPUI) / Reduction of the polymerization shrinkage stress inherent of dimethacrylate-based resin composites has been a work in progress since the phenomenon was first described by Dr. Rafael L. Bowen in 1967. Contemporary efforts to modify the composites or the curing protocols for polymerization have proven a challenging task with controversial results. Influenced by existing mathematical models relating exposure, curing time and depth of cure of resin composites, a novel method for the reduction of polymerization shrinkage stress is proposed. By polymerizing through a single aperture mask, a dental light curing unit is transformed from a planar light source to a point light source, and a fully cured, three-dimensional “bullet” shaped curing front is predicted for the cured resin below. So long as the edges of the bullet do not touch the cavity walls or floor, the shrinkage stress of the bullet is not transferred. Follow-up with an unmasked curing unit then fully polymerizes the restoration. By reducing the volume of uncured composite in contact with the cavity walls and floor, shrinkage stress of the restoration is also reduced. The objective of the present study was to demonstrate this curing phenomenon with a model resin composite using masks with aperture diameters of 0.5, 0.4, and 0.25 mm and curing times of 10, 20, 30, and 40 seconds. The resulting curing front was evaluated quantitatively and qualitatively. From this, mathematical models of the curing front were derived. Selected combinations of aperture mask and curing time were then investigated to evaluate the influence of this phenomenon on the degree of conversion, Knoop hardness, and polymerization shrinkage stress of the same model resin composite. Group differences were analyzed using a one-way ANOVA at 5% significance.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / PURPOSE: To assess the influence of simulated oral erosive/abrasive challenges on the bond strength of an etch-and-rinse two-step bonding system to enamel using an in situ/ex vivo protocol. METHODS: Bovine enamel blocks were prepared and randomly assigned to four groups: CONT - control (no challenge), ABR - 3x/day-1 minute toothbrushing; ERO - 3x/day - 5 minutes extraoral immersion into regular Coca Cola; and ERO+ABR - erosive protocol followed by a 1-minute toothbrushing. Eight blocks were placed into an acrylic palatal appliance for each volunteer (n = 13), who wore the appliance for 5 days. Two blocks were subjected to each of the four challenges. Subsequently, all the blocks were washed with tap water and Adper Single Bond 2/Filtek Z350 were placed. After 24 hours, 1 mm2 beams were obtained from each block to be tested with the microtensile bond strength test (50 N load at 0.5 mm/minute). The data were statistically analyzed by one-way RM-ANOVA and Tukey's tests (alpha = 0.05). RESULTS: No difference was detected among the ABR, ERO, and CONT groups (P > 0.05). ERO+ABR group yielded lower bond strengths than either the ABR and ERO groups (P < 0.0113). / Revisión por pares