Indiana University-Purdue University Indianapolis (IUPUI) / Objective: CAD/CAM technology allows fabrication of thin lithium disilicate (LD) veneers to a LD crown substructure in place of using traditional feldspathic porcelain (FP) which has inferior mechanical properties. This project investigated the effect of different LD veneer applications to LD substructure on the biaxial flexural fatigue of LD veneer/substructure restorations. Materials/Methods: Forty-five LD discs (Ø = 120.7 mm) were fabricated that, when combined with the veneering discs, achieve final dimensions of (Ø = 121.2mm). Experimental groups were (n = 15) as follows: (1) Resin Bonded LD Veneer (RBLDV), LD veneer (Ø = 120.5 mm) adhesively cemented to LD (0.7 mm); (2) Sintered LD Veneer (SLDV), LD veneer (Ø=120.5 mm) sintered to LD (0.7 mm); (3) Sintered Feldspathic Veneer (SFV), feldspathic porcelain (FP) applied to LD discs to achieve a final dimension of (Ø = 121.2 mm). A fourth group of (1.2 mm) monolithic LD served as the control. Weibull-distribution survival analysis was used to compare the differences of the resistance to fracture after fatigue between groups. Total number of cycles were analyzed using one-way Anova (p < 0.05). Hypothesis: Adhering or sintering a thin laminate layer of LD on another LD surface would result in increased fracture resistance in comparison to sintered FP on LD. Results: The SFV group had significantly lower fatigue resistance than SLDV and RBLDV groups (p < 0.05). The RBLDV group fractures resulted in significantly more fractured fragments in comparison to the other groups. No statistical difference was observed in the number of cycles. The results also showed that the LD veneered groups presented similar resistance to fatigue as monolithic discs of the same overall dimensions. Conclusion: The hypothesis was accepted suggesting that veneering a LD substructure with a LD veneer, bonded or sintered, has increased resistance to fatigue as FP veneering material on a LD substructure. In addition, it was observed to have similar resistance to fatigue in comparison to the monolithic LD group.

Syfte: Syftet med denna studie var att undersöka resistens mot marginala missfärgningar av en adhesivt cementerad keram till emalj beroende på typ av cement, teknik för avlägsnande av överskottscement och kombinationen av de två faktorerna.Metod: 60 extraherade tänder preparerades i emalj med en slipmaskin till en 90° vinkel. Sintrat IPS E-max CAD preparerades till 60 bitar med måtten 3x3x1mm. Glaskerambitarna cementerades med Variolink®Veneer, Variolink®II och Panavia™F 2.0 enligt bruksanvisning med en kraft på 5kg. Varje cementgrupp bestod av 20 provkroppar där cementöverskottet avlägsnades med putsning eller konventionell teknik. Detta ledde till totalt 6 grupper med 10 provkroppar i varje grupp. Provkropparna termocyklades i 5000 cyklar i destillerat vatten med temperaturen 5° C till 55° C, därefter placerades provkropparna 4 dagar i kaffe och 4 dagar i rött vin. Missfärgningsgraden av det marginala cementet avlästes i en blindad studie under mikroskop av två observatörer med signifikant klinisk erfarenhet inom dentala keramer. Resultat: Variolink®Veneer var det minst missfärgande cementet oberoende av avlägsningsteknik, men resultatet var inte statistiskt signifikant. Putsning visade bättre motstånd gällande missfärgning jämfört med konventionell teknik och detta resultat var statistiskt signifikant. Variolink®II tillsammans med putstekniken var det minst missfärgande kombinationerna.Signifikans: Inom de begränsningar en in vitro studie medför kan följande slutsats dras; den viktigaste parametern gällande resistens av marginal missfärgning är ej val av cement utan tekniken för avlägsning av överskottscement. / Purpose: The aim of this study was to investigate the resistance to marginal discoloration of an adhesively cemented bondable ceramic to enamel depending on choice of cement, the technique used for removing excess cement and a combination of the two factors. Method: 60 extracted teeth were prepared in the enamel with a grinding machine to an approximately 90° angle. A block of IPS E-max CAD was sintered and thereafter sliced into 60 pieces with the measurement 3x3x1mm. The ceramic pieces were cemented with Variolink®Veneer, Variolink®II and Panavia™F 2.0 following the manufacturer’s instructions with a force of 5kg (20 specimens in each group). The excess cement was removed by either polishing technique or conventional technique leading to 6 groups with 10 specimens in each group. The specimens were thermocycled for 5000 cycles in 5° C and 55° C distilled water baths and after placed in coffee for 4 days and red wine for 4 days. The discoloration degree of the cement margin was analysed blindly under microscope by two observers with significant clinical experience in dental ceramics.Results: Variolink®Veneer was the least discolored cement but the result was not statistical significant. When comparing polishing and conventional technique, polishing showed least discoloration independent of choice of cement. Variolink®II together with the polishing technique showed least discoloring mean and median value of the 6 groups.Significance: Within the restrictions an in vitro study has, the following conclusion can be made; the most important parameter regarding resistance to marginal discoloration is not the choice of cement but how the excess cement is removed.

Flatness of wood composite panels, such as Laminated Veneer Lumber, is often difficult to control during the manufacturing process. Out-of-plane deformation, or warpage, of wood veneers caused by changes in moisture content affects the ability to press flat panels. To understand wood panel warpage, experimental methods are developed to create and measure moisture-induced deformation of wood veneers on five species of various thicknesses. Three moisture induction methods are investigated and evaluated to determine the increase in moisture content. Experiments are developed to produce moisture gradients of two concentrations in the veneers to examine the effect on warpage behavior. Additionally, the surface area of applied moisture and veneer thickness is also investigated. Three-dimensional scanning technology is used to measure warpage of veneers. A procedure using a structured-light scanner is developed to analyze the surface curvatures to observe the effect of moisture-induced warpage. After moisture-induction treatment of the veneer, surface deformation data is measured using the scanner and the data is converted into a 3D solid body model that is used for curvature comb analysis. The results show that curvature comb analysis can be used to analyze the geometry of moisture-induce warpage. The method can be used to analyze the effect of moisture gradient variables on warpage behavior including concentration, veneer thickness, and surface area. The experimental methods developed can be used by future researchers to validate theoretical warpage prediction models. / Master of Science / Flatness of wood composite panels, such as Laminated Veneer Lumber, is often difficult to control during the manufacturing process. Warpage of wood veneers is caused by changes in moisture content affecting manufacturers' ability to press flat panels. To understand wood panel warpage, experimental methods are developed to create and measure moisture-induced warpage of wood veneers on five species of various thicknesses. Three moisture induction methods are investigated and evaluated to determine the increase in moisture content. Experiments are developed to produce moisture gradients of two concentrations in the veneers to examine the effect on warpage behavior. Additionally, the surface area of applied moisture and veneer thickness is also investigated. Three-dimensional scanning technology is used to measure warpage of veneers. A procedure is developed to analyze the surface curvatures to observe the effect of moisture-induced warpage. After moisture-induction treatment of the veneer, surface deformation data is measured and converted into a 3D solid body model that is used to analyze curvature. The results show that moisture induction methods used to induce warpage can experience different geometries to analyze a veneer's curvature. The methods can be used to analyze warpage behavior of veneers by future researchers to validate warpage prediction model.

The aim of this study was to evaluate the marginal staining of ceramic laminates cemented with and without the presence of enamel preparation. Thirty-two (32) permanent central incisors were selected and randomly divided into two groups (CP and SP). In group-CP (n = 16) the laminates were bonded to the prepared enamel and in group-SP (n=16) laminates were cemented directly over the intact enamel, with no preparation. The preparation and cementation were standardized and performed by a single operator. Each group was subdivided into two subgroups (n = 8) which correspond to different immersion media - coffee and water ( SPc , SPa , CPc and CPa ). After an immersion period of 10 days, stereomicroscope pictures with 20X of the mesial, distal, cervical and incisal surface of each specimen were made. The interfaces tooth - resin cement - laminate were evaluated by three blind, trained and calibrated examiners. Data were subjected to statistical Kruskal - Wallis and Mann - Whitney analysis. The prepared group as well as the unprepared group showed higher marginal staining when immersed in coffee. When immersed in coffee, the prepared laminates presented more marginal staining then unprepared laminates. But when immersed in water there was no statistically significant difference between the groups. The adhesive interface of ceramic laminates cemented on prepared enamel presented more marginal staining than laminates cemented on intact enamel, with no preparation, after immersion in staining solution. / O objetivo deste trabalho foi avaliar o manchamento marginal de laminados cerâmicos cimentados com e sem a presença de preparo do esmalte. Trinta e dois (32) incisivos inferiores permanentes hígidos foram selecionados e aleatoriamente divididos em dois grupos (CP e SP). No grupo CP (n=16) os laminados foram cimentados sobre o esmalte preparado e no grupo SP (n=16) os laminados foram cimentados diretamente sobre o esmalte intacto, sem preparo. Os preparos e a cimentação foram padronizados e realizados por um único operador. Cada grupo foi subdividido em dois subgrupos (n=8) que correspondem a diferentes meios de imersão café e água (SPc, SPa, CPc e CPa). Após um período de imersão de 10 dias, foram feitas imagens em Estereomicroscópio com aumento de 20X das faces mesial, distal, cervical e incisal de cada corpo de prova. As interfaces dente - cimento resinoso - laminado foram avaliadas por três examinadores cegos, treinados e calibrados. Os dados foram submetidos aos testes estatísticos Kruskal-Wallis e Mann-Whitney. Os corpos de prova imersos no café apresentaram maior manchamento que os imersos na água, tanto no grupo com preparo como no sem preparo. As interfaces dos laminados com preparo mancharam mais do que os sem preparo quando imersos em café. Porém quando imersos em água não houve diferença estatisticamente significante entre os grupos. Pode-se concluir que a interface adesiva de laminados cerâmicos cimentados sobre esmalte preparado apresenta maior manchamento do que os laminados cimentados sobre o esmalte intacto quando submersos em solução corante.

Made available in DSpace on 2014-06-11T19:35:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-04-27Bitstream added on 2014-06-13T19:44:48Z : No. of bitstreams: 1 almilhatti_hj_dr_arafo.pdf: 2065564 bytes, checksum: 9ca5fe747a7a70b66a300c7564a4ad19 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este estudo teve como objetivo avaliar a efetividade de quatro condicionadores de metal (Metal Photo Primer, MPP; Cesead II Opaque Primer, OP; Targis Link, TL e Siloc, S) aplicados sobre diferentes superfícies das ligas de Ni-Cr, Co-Cr e do metal Ti Cp. Após o polimento metalográfico e jateamento com Al2O3, foram obtidos três grupos experimentais para cada metal : Grupo polimento (P) - controle; Grupo (J50), jateado com Al2O3 de 250 um. A esses grupos foram aplicados os condicionadores e as resinas opaca e de revestimento estético (Artglass). Decorridos 24 horas de armazenamento em água a 37ºC, cada grupo foi dividido em dois grupos e submetidos aos ensaios mecânicos de cisalhamento (0,5 mm/min.), um antes e outro após 500 ciclos térmicos (60ºC e 4ºC). As superfícies fraturadas foram analisadas e o padrão de falhas determinado. Adicionalmente foram feitas análises de MEV e EDS. Seguem os resultados para cada metal: Liga de Ni-Cr: para os Grupos P e J50, não foram observadas diferenças (p>0,05) nos valores médios de tensão de cisalhamento entre os condicionadores OP e TL e entre MPP e S, sendo maiores as médias dos dois primeiros. Não foram encontradas diferenças (p>0,05) entre as médias de tensão para os condicionadores do Grupo J250. No entanto, esses valores foram superiores aos do Grupo J50. Após a termociclagem, as médias para os condicionadores OP, S e TL não apresentaram aumento significante (p>0,05), enquanto a média para o MPP aumentou (p<0,05). Liga de Co-Cr, para o Grupo P, não foram observadas diferenças (p>0,05) nos valores médios de tensão entre os condicionadores OP e TL e entre MPP e S, sendo superiores as médias dos dois primeiros. As médias de tensão para o Grupo J250 foram estatisticamente maiores às do Grupo J50,... / The purpose of the study was to evaluated the effect of three adhesive primers (Metal Photo Primer, MPP; Cesead II Opaque Primer, OP; Targis Link, TL) and a bonding system (Siloc, S) on the shear bond strength between a prosthetic composite material (Artglass) to Ni-Cr alloy (Wiron 99), Co-Cr alloy (Wironit), and CP Ti (Tritan). Disk patterns were cast of the 3 alloys. All the disk surfaces were abraded with No. 80, 320, and 600 SiC paper, respectively and three different surface treatment were applied: No. 600 SiC polishing, P; 50 mm Al2O3 sandblasting, S50; 250 mm Al2O3 sandblasting, S250. The composites (Artglass opaque and dentin) were applied using a cylindrical stainless steel split according to manufacturer's instructions then light polymerized. Specimens without primer and bonding system were also prepared as control. The specimens were stored in water a 37oC for 24 h and then shear bond strengths were determined both before and after immersed alternately in water baths at 4oC and 60oC for 15 seconds each for up to 500 thermal cycles before shear mode testing at a crosshead speed of 0.5 mm/min. Data were statistically analyzed using 3-way ANOVA and 1-way ANOVA, followed by Tukey multiple range intervals calculated at the 0.05 significance level. Fractured interfaces were analyzed by use of light microscopy and SEM. Results: Ni-Cr alloy: The bond strength of the P-OP/J50-OP group and P-TL/J50- TL group were statistically comparable (p>0,05) and exhibited greater strength than the P-MPP/J50-MPP group and P-S/J50-S (p<0,05). No significant differences were found among the four conditioners for J250 group (p>0,05), and these group showed the greater strength than the J50 group (p<0,05). After thermocycling, no significant differences (p>0,05) were found among the three primers (OP, S, TL) and the bond strength of MPP increased...(Complete abstract, click electronic access below)

Objetivo: Comparar el conocimiento sobre el uso de las carillas dentales en estudiantes de pregrado de distintas facultades universitarias de Lima, Perú. Materiales y métodos: 434 estudiantes de pregrado de distintas facultades universitarias de Lima - Perú (Ciencias Sociales, Comerciales y Derecho (n=166); Ingeniería, Industria y Construcción (n=137); y Ciencias de la Salud (n=131) fueron encuestados a través de un cuestionario validado para comparar sus conocimientos sobre el uso de carillas dentales, enviadas a través de plataformas digitales en el periodo de setiembre - octubre del año 2020. El análisis univariado fue realizado a través de la estadística descriptiva (frecuencia absoluta y relativa) de las variables cualitativas y las medidas de tendencia central y de dispersión (mediana y rango intercuartílico) de la variable cuantitativa ‘‘edad’’. El análisis bivariado fue realizado mediante el test de ANOVA de una vía, utilizando la media y ±desviación estándar de las variables ‘‘puntuación’’ y ‘‘facultad universitaria’’ (α≤0.05). Resultados: No se encontraron diferencias significativas al comparar el conocimiento sobre el uso de las carillas dentales entre los estudiantes de pregrado de las facultades universitarias de Ciencias Sociales, Comerciales y Derecho (13.35±2.27); Ingeniería, Industria y Construcción (13.16±2.55) y Ciencias de la Salud (13.40±3.09) de Lima, Perú. (p= 0.723) Conclusiones: No se halló diferencias en el conocimiento sobre el uso de carillas dentales entre las facultades universitarias. Como profesionales de la salud debemos reforzar y actualizar la información clínica brindada a través de los distintos medios de información dado que existe aún desconocimiento y se necesita una mayor concientización sobre este tratamiento. / Objective: Compare the knowledge about the use of dental veneers in undergraduate students from different university faculties in Lima, Peru Materials and methods: 434 undergraduate students from different university faculties of Lima - Peru (Social, Commercial and Law Sciences (n = 166); Engineering, Industry and Construction (n = 137); and Health Sciences (n = 131) were surveyed through of a validated questionnaire to compare their knowledge about the use of dental veneers, sent through digital platforms in the period September - October 2020. The univariate analysis was performed through descriptive statistics (absolute and relative frequency) of the qualitative variables and the measures of central tendency and dispersion (median and interquartile range) of the quantitative variable ''age'', the variables ''score'' and ''university faculty'' (α≤0.05). Results: No significant differences were found when comparing knowledge about the use of dental veneers among undergraduate students of the university faculties of Social, Business and Law Sciences (13.35 ± 2.27); Engineering, Industry and Construction (13.16 ± 2.55) and Health Sciences (13.40 ± 3.09) from Lima, Peru. (p = 0.723) Conclusions: There were no differences between the knowledge about the use of dental veneers between the university faculties. As health professionals we must reinforce and update the clinical information provided through the different information media since there is still a lack of knowledge and a greater awareness of this treatment is needed. / Tesis

The print newspaper has been a fundamental part of liberal democracies since their inception. Its origin lies in the invention of the moveable-type printing press by Gutenberg in the mid-15th century but, as other technological communication tools were developed, especially in the 20th century, it gradually lost its share in the media landscape. This master’s thesis explores the materiality of the newspaper as it is being replaced by digital counterparts. What does this shift entail from an Interaction Design perspective? A literature review, semi-structured interviews, and a material-centred interaction design process are used to delve into this question. The result is a Speculative Design artefact made of wood veneers that vindicates Slow Technology Design as an approach for a meaningful news-reading experience. Additionally, it is suggested the consideration of a holistic approach from the humanities and Media Ecology to enrich the critical approach of Interaction Design towards technology.

AbstraktSyfte:Studiens syfte var att utreda maxlasttoleransen mellan yttria-stabiliserad zirkoniumdioxid- (Y-TZP) och metallkeramiska- (MC) molarkronor med en ny design på in vitro belastningsformen. En stålkula användes för att utöva last på kusparna istället för i fissuren för att framställa en sprickbildning liknande den som ses kliniskt. Materialochmetod:26 kronor tillverkades, varav 13 högädla MC och 13presintrade Y-TZP. 7 av MC göts av 50% tidigare icke-gjuten och 50% omgjuten legering medan de kvarvarande 6 göts av 100% tidigare icke gjuten legering. Kronorna täcktes av ett fasadporslinoch cementerades på stansar av ett resinmaterial. Av de 26 kronorna genomgick 24 förbelastingstester och belastades slutligen till fraktur. Resultat: MC klarade signifikant högre belastningar än Y-TZP, P>0,001. Frakturerna skiljde sig också grupperna emellan där MC-gruppen uppvisade enbart adhesiva frakturer av fasadporslinet under det att Y-TZP-gruppen uppvisade kohesiva brott i ytporslinet undantaget en Y-TZP-krona som uppvisade total fraktur. Ingen signifikant skillnad kunde ses mellan MC-kronor bestående av enbart tidigare icke gjuten legering och MC-kronor med 50% omgjuten legering, P=0,370. Konklusion: MC-kronor klararsignifikant högre belastningar än Y-TZP-kronor och testet genererar kliniskt relevanta frakturer av ytporslinet snarare än totala frakturer. Frakturbeteendet skiljer sig mellan MC och Y-TZP där MC uppvisar endast adhesiva fraktureroch Y-TZP främst kohesiva brott av ytporslinet.

O objetivo desse estudo foi avaliar o grau de conversão, a estabilidade de cor e translucidez de cimentos resinosos para cimentação de laminados cerâmicos em duas espessuras, submetidos a diferentes protocolos de envelhecimento. Foram utilizados 270 incisivos bovinos hígidos, cujas porções radiculares foram cortadas e as porções coronárias foram incluídas em matriz de PVC (25mm de diâmetro) com resina acrílica. As faces vestibulares foram planificadas até a dentina. Foram confeccionados 240 corpos-de-prova em cerâmica prensada (IPS e-max Press e IPS e- maxZirpress, IvoclarVivadent), em duas espessuras (0,5 mm e 1,0 mm), que foram separados aleatoriamente em dois grupos, segundo o tipo de cimento resinoso utilizado para fixação: fotoativado (Variolink II, Ivoclar/Vivadent) ou dual (Rely U 200, 3M ESPE). Após a cimentação, todas as amostras foram mantidas em estufa a 37°C por 24h, após o qual foram realizadas as leituras de cor e translucidez iniciais (Vita EasyShade, VITA). Em seguida, as amostras foram subdivididas em três grupos (n=10) de acordo com o envelhecimento a que foram submetidos: Controle sem envelhecimento; imersão em água destilada por 1 ano e fadiga termomecânica (1.200.000 ciclos, frequência de1,3Hz e ciclagem térmica de 5°C/37°C/55°C). Como controle, foram obtidos 30 corpos-de-prova de cada cimento resinoso (0,5mm) e 30 dentes foram planificados e submetidos aos mesmos processos de envelhecimento, após o qual leituras finais foram realizadas. Foram analisados também o grau de conversão dos cimentos polimerizados através das restaurações (FTIR) e a linha de cimentação em cada um dos grupos (n=3), antes e depois do envelhecimento. Para isso, as amostras, selecionadas aleatoriamente, foram seccionadas no sentido longitudinal e analisadas em estereomicroscópio de dupla coordenada (Nikon Measurescope). Os dados de estabilidade de cor (&Delta;E), translucidez, grau de conversão e linha de cimentação foram submetidas à análise estatística (3-way ANOVA, Tukey, p<0,05). O cimento autoadesivo apresentou maior grau de conversão que o fotoativado (p<0,05) quando utilizada a cerâmica Zirpress, mas produziu maior alteração de cor (p<0,05) e menor translucidez nas restaurações de E-maxPress de 0,5mm. A ciclagem termomecânica não foi significante para alterações óticas dos sistemas cerâmicos testados. Conclui-se que a espessura do laminado cerâmico não altera o grau de conversão dos cimentos resinosos e o tipo de cimento resinoso influencia a estabilidade de cor das restaurações cerâmicas quando submetido ao envelhecimento com água destilada. / The aim of this study is to evaluate the degree of conversion, color stability and translucency of resin cement for luting ceramic veneers with two thicknesses submitted to different aging protocols. Two hundred and seventy bovine incisors were used, which had the root cut, and the coronal were embedded in acrylic resin into PVC rings (25mm diameter). The buccal surface was flattened until dentin. Two hundred and forty pressed ceramic veneers (IPS e-max Press and IPS e-max ZirPress, IvoclarVivadent) were obtained, in two thicknesses (0,5 mm and 1.0 mm), that were randomly separated into two groups according to the type of resin cement used for luting: light-cured (Variolink II, Ivoclar / Vivadent) or dual cured (Rely U 200, 3M ESPE). After the cementation, all samples were maintained at 37 °C for 24 h; after first color and translucency readings (Vita EasyShade, VITA) were made. The samples were separated into 3 groups (n=10) according to the aging that was submitted: control without aging, immersion in distilled water for one year and thermomechanical cycling (1.200.000 cycles, frequency of 1,3Hz and thermal cycling of 5°C/37°C/55°C). As the control group, 30 samples of each resin cement (0,5 mm) and flattened teeth were obtained and submitted to the same aging protocols. After tests, the final color and translucency readings were taken. The degree of conversion of resin cements through veneer restoration, and the cement film thickness (n=3) for each group were analyzed (FTIR), before and after aging. For this, the samples were randomly selected, sectioned longitudinally and examined by a stereomicroscope (Nikon Measurescope). The results of color stability (&Delta;E), translucency, degree of conversion and cement film thicknesses were statistically analyzed (3-way, ANOVA, Tukey, p<0.05). The self-adhesive cement showed the higher degree of conversion than light-activated luting cement (p<0.05) when Zirpress ceramic was used, but produced higher color change (p<0.05) and lower translucency in 0.5mm E-maxPress restorations. The thermomechanical cycling was not significant for optical changes of tested ceramic systems. It was concluded that the thickness of ceramic veneers didnt alter the degree of conversion of resin cement and the type of resin cement has influenced the color stability of ceramic restorations when submitted to water aging.

O objetivo desse estudo foi avaliar o grau de conversão, a estabilidade de cor e translucidez de cimentos resinosos para cimentação de laminados cerâmicos em duas espessuras, submetidos a diferentes protocolos de envelhecimento. Foram utilizados 270 incisivos bovinos hígidos, cujas porções radiculares foram cortadas e as porções coronárias foram incluídas em matriz de PVC (25mm de diâmetro) com resina acrílica. As faces vestibulares foram planificadas até a dentina. Foram confeccionados 240 corpos-de-prova em cerâmica prensada (IPS e-max Press e IPS e- maxZirpress, IvoclarVivadent), em duas espessuras (0,5 mm e 1,0 mm), que foram separados aleatoriamente em dois grupos, segundo o tipo de cimento resinoso utilizado para fixação: fotoativado (Variolink II, Ivoclar/Vivadent) ou dual (Rely U 200, 3M ESPE). Após a cimentação, todas as amostras foram mantidas em estufa a 37°C por 24h, após o qual foram realizadas as leituras de cor e translucidez iniciais (Vita EasyShade, VITA). Em seguida, as amostras foram subdivididas em três grupos (n=10) de acordo com o envelhecimento a que foram submetidos: Controle sem envelhecimento; imersão em água destilada por 1 ano e fadiga termomecânica (1.200.000 ciclos, frequência de1,3Hz e ciclagem térmica de 5°C/37°C/55°C). Como controle, foram obtidos 30 corpos-de-prova de cada cimento resinoso (0,5mm) e 30 dentes foram planificados e submetidos aos mesmos processos de envelhecimento, após o qual leituras finais foram realizadas. Foram analisados também o grau de conversão dos cimentos polimerizados através das restaurações (FTIR) e a linha de cimentação em cada um dos grupos (n=3), antes e depois do envelhecimento. Para isso, as amostras, selecionadas aleatoriamente, foram seccionadas no sentido longitudinal e analisadas em estereomicroscópio de dupla coordenada (Nikon Measurescope). Os dados de estabilidade de cor (&Delta;E), translucidez, grau de conversão e linha de cimentação foram submetidas à análise estatística (3-way ANOVA, Tukey, p<0,05). O cimento autoadesivo apresentou maior grau de conversão que o fotoativado (p<0,05) quando utilizada a cerâmica Zirpress, mas produziu maior alteração de cor (p<0,05) e menor translucidez nas restaurações de E-maxPress de 0,5mm. A ciclagem termomecânica não foi significante para alterações óticas dos sistemas cerâmicos testados. Conclui-se que a espessura do laminado cerâmico não altera o grau de conversão dos cimentos resinosos e o tipo de cimento resinoso influencia a estabilidade de cor das restaurações cerâmicas quando submetido ao envelhecimento com água destilada. / The aim of this study is to evaluate the degree of conversion, color stability and translucency of resin cement for luting ceramic veneers with two thicknesses submitted to different aging protocols. Two hundred and seventy bovine incisors were used, which had the root cut, and the coronal were embedded in acrylic resin into PVC rings (25mm diameter). The buccal surface was flattened until dentin. Two hundred and forty pressed ceramic veneers (IPS e-max Press and IPS e-max ZirPress, IvoclarVivadent) were obtained, in two thicknesses (0,5 mm and 1.0 mm), that were randomly separated into two groups according to the type of resin cement used for luting: light-cured (Variolink II, Ivoclar / Vivadent) or dual cured (Rely U 200, 3M ESPE). After the cementation, all samples were maintained at 37 °C for 24 h; after first color and translucency readings (Vita EasyShade, VITA) were made. The samples were separated into 3 groups (n=10) according to the aging that was submitted: control without aging, immersion in distilled water for one year and thermomechanical cycling (1.200.000 cycles, frequency of 1,3Hz and thermal cycling of 5°C/37°C/55°C). As the control group, 30 samples of each resin cement (0,5 mm) and flattened teeth were obtained and submitted to the same aging protocols. After tests, the final color and translucency readings were taken. The degree of conversion of resin cements through veneer restoration, and the cement film thickness (n=3) for each group were analyzed (FTIR), before and after aging. For this, the samples were randomly selected, sectioned longitudinally and examined by a stereomicroscope (Nikon Measurescope). The results of color stability (&Delta;E), translucency, degree of conversion and cement film thicknesses were statistically analyzed (3-way, ANOVA, Tukey, p<0.05). The self-adhesive cement showed the higher degree of conversion than light-activated luting cement (p<0.05) when Zirpress ceramic was used, but produced higher color change (p<0.05) and lower translucency in 0.5mm E-maxPress restorations. The thermomechanical cycling was not significant for optical changes of tested ceramic systems. It was concluded that the thickness of ceramic veneers didnt alter the degree of conversion of resin cement and the type of resin cement has influenced the color stability of ceramic restorations when submitted to water aging.