Academisch Proefschrift--Leiden. / Includes bibliographical references.

Os objetivos deste trabalho foram: a quantificação da microinfiltração e desadaptação antes e após cimentação de coroas totais cerâmicas, com quatro tipos de sistemas de infra-estrutura e a correlação entre desadaptação e microinfiltração. Após aprovação pelo Comitê de Ética da FOUSP, 40 terceiros molares humanos receberam coroais totais cerâmicas, sendo: 2 cerâmicas infiltradas por vidro (In-Ceram alumina Slip-Cast (S) e o bIoco In-Ceram Alumina CA-12 (CA)) e 2 cerâmicas de alumina policristalina (Procera/Nobel Biocare (P) e o bloco In-Ceram Al-20, CEREC In-Lab (CE)), (n=10). O espaço entre coroa e dente foi medido antes e depois da cimentação das coroas. Foram submetidos à ciclagem mecânica (100.000 ciclos, 8 Kgf, 4 Hz), térmica (700 ciclos, 5/55ºC por minuto), submersos em azul de metileno 0,5% por 4 horas e seccionados nos sentidos mésio/distal e vestíbulo/lingual. As imagens foram obtidas em estereomicroscópio (20X) e os dados de desadaptação foram submetidos à ANOVA (e Tukey). Os escores da microinfiltração foram submetidos à análise da concordância dos avaliadores e Kruskal-Wallis. Não houve diferenças significantes entre os sistemas cerâmicos (S= 38, P= 49, CA= 48 e CE= 39?m). O fator \"região\" da linha de cimentação apresentou diferenças estatísticas. A desadaptação foi maior na parede pulpar (60 ?m), seguida dos ângulos axio-pulpar e gengivo-axial (57 e 48 ?m, respectivamente). As paredes axiais e margens foram os locais de menor desadaptação (27 e 26 ?m, respectivamente). Houve diferença estatística entre as duas técnicas de medida, antes e após a cimentação (46 e 41?m, respectivamente). Houve diferença estatisticamente significante entre os quatro tipos de sistemas cerâmicos avaliados quanto à microinfiltração, onde S e CE apresentaram maiores níveis de infiltração, seguidos de P e CA. Não houve correlação entre microinfiltração e desadaptação. Concluiu-se que os quatro sistemas cerâmicos avaliados produziram coroas totais com linha de cimentação dentro dos limites clinicamente aceitáveis. / The objectives of this study were to quantify the microleakage and the loss of marginal adaptation before and after cementation of all-ceramic crowns, with four types of infrastructure systems, and to compare these parameters. After approval by the Committee on Ethics in Research of Dental School of University of São Paulo, 40 human third molars received all-ceramic crowns, 2 glass-infiltrated ceramics (In-Ceram alumina Slip-Cast (S) and the block In-Ceram Alumina CA-12 (CA) ) and 2 polycrystalline alumina ceramics (Procera / Nobel Biocare (P) and the block Ceram In-Al-20, CEREC In-Lab (EC) (n = 10). The gap between ceramic dental prosthesis and tooth was measured before and after cementation of the crowns. They were subjected to mechanical load cycling (100,000 cycles, 8 Kgf, 4 Hz), thermocycling (700 cycles, 5 / 55 ° C per minute), immersed in 0.5% methylene blue dye for 4 hours and then sectioned in the mesial / distal and buccal / lingual aspects. The images were obtained in stereomicroscope (20X) and the marginal fit data were evaluated by ANOVA (and Tukey test). The microleakage values were analyzed by the correlation analysis of examiners and the Kruskal-Wallis test. There were no significant differences between the ceramic systems (S = 38, P = 49, CA = 50 and CE = 39 ? m). The factor \"region\" of the cementation line has presented statistical differences. The loss of adaptation was higher on the pulpal wall (61 ? m), followed by gingival-axial (49 ? m) and axial-pulpal (58 ? m) angles. The axial walls and margins were the sites of the smallest displacement (27 and 26 ?m, respectively). There was statistical difference between the two techniques of measurement, before and after cementation (47 and 41 ?m, respectively). Statistically significant difference among the four types of ceramic systems was detected for microleakage, whereas S and CE showed higher levels of infiltration, followed by P and CA. However, no correlation was found between microleakage and loss of marginal adaptation. It was concluded that the four systems produced all-ceramic crowns with the line of cementation within clinically acceptable limits.

Os objetivos deste trabalho foram: a quantificação da microinfiltração e desadaptação antes e após cimentação de coroas totais cerâmicas, com quatro tipos de sistemas de infra-estrutura e a correlação entre desadaptação e microinfiltração. Após aprovação pelo Comitê de Ética da FOUSP, 40 terceiros molares humanos receberam coroais totais cerâmicas, sendo: 2 cerâmicas infiltradas por vidro (In-Ceram alumina Slip-Cast (S) e o bIoco In-Ceram Alumina CA-12 (CA)) e 2 cerâmicas de alumina policristalina (Procera/Nobel Biocare (P) e o bloco In-Ceram Al-20, CEREC In-Lab (CE)), (n=10). O espaço entre coroa e dente foi medido antes e depois da cimentação das coroas. Foram submetidos à ciclagem mecânica (100.000 ciclos, 8 Kgf, 4 Hz), térmica (700 ciclos, 5/55ºC por minuto), submersos em azul de metileno 0,5% por 4 horas e seccionados nos sentidos mésio/distal e vestíbulo/lingual. As imagens foram obtidas em estereomicroscópio (20X) e os dados de desadaptação foram submetidos à ANOVA (e Tukey). Os escores da microinfiltração foram submetidos à análise da concordância dos avaliadores e Kruskal-Wallis. Não houve diferenças significantes entre os sistemas cerâmicos (S= 38, P= 49, CA= 48 e CE= 39?m). O fator \"região\" da linha de cimentação apresentou diferenças estatísticas. A desadaptação foi maior na parede pulpar (60 ?m), seguida dos ângulos axio-pulpar e gengivo-axial (57 e 48 ?m, respectivamente). As paredes axiais e margens foram os locais de menor desadaptação (27 e 26 ?m, respectivamente). Houve diferença estatística entre as duas técnicas de medida, antes e após a cimentação (46 e 41?m, respectivamente). Houve diferença estatisticamente significante entre os quatro tipos de sistemas cerâmicos avaliados quanto à microinfiltração, onde S e CE apresentaram maiores níveis de infiltração, seguidos de P e CA. Não houve correlação entre microinfiltração e desadaptação. Concluiu-se que os quatro sistemas cerâmicos avaliados produziram coroas totais com linha de cimentação dentro dos limites clinicamente aceitáveis. / The objectives of this study were to quantify the microleakage and the loss of marginal adaptation before and after cementation of all-ceramic crowns, with four types of infrastructure systems, and to compare these parameters. After approval by the Committee on Ethics in Research of Dental School of University of São Paulo, 40 human third molars received all-ceramic crowns, 2 glass-infiltrated ceramics (In-Ceram alumina Slip-Cast (S) and the block In-Ceram Alumina CA-12 (CA) ) and 2 polycrystalline alumina ceramics (Procera / Nobel Biocare (P) and the block Ceram In-Al-20, CEREC In-Lab (EC) (n = 10). The gap between ceramic dental prosthesis and tooth was measured before and after cementation of the crowns. They were subjected to mechanical load cycling (100,000 cycles, 8 Kgf, 4 Hz), thermocycling (700 cycles, 5 / 55 ° C per minute), immersed in 0.5% methylene blue dye for 4 hours and then sectioned in the mesial / distal and buccal / lingual aspects. The images were obtained in stereomicroscope (20X) and the marginal fit data were evaluated by ANOVA (and Tukey test). The microleakage values were analyzed by the correlation analysis of examiners and the Kruskal-Wallis test. There were no significant differences between the ceramic systems (S = 38, P = 49, CA = 50 and CE = 39 ? m). The factor \"region\" of the cementation line has presented statistical differences. The loss of adaptation was higher on the pulpal wall (61 ? m), followed by gingival-axial (49 ? m) and axial-pulpal (58 ? m) angles. The axial walls and margins were the sites of the smallest displacement (27 and 26 ?m, respectively). There was statistical difference between the two techniques of measurement, before and after cementation (47 and 41 ?m, respectively). Statistically significant difference among the four types of ceramic systems was detected for microleakage, whereas S and CE showed higher levels of infiltration, followed by P and CA. However, no correlation was found between microleakage and loss of marginal adaptation. It was concluded that the four systems produced all-ceramic crowns with the line of cementation within clinically acceptable limits.

OBJECTIVES: Evaluate the effect of different veneering techniques, Y-TZP core thicknesses, and firing cycles with different heat rates and holding times on the mechanical properties of veneering porcelain. MATERIALS AND METHODS: Biaxial flexural strength and Thermal shock resistance tests were conducted to evaluate the mechanical properties of veneer porcelain. Core material, Y-TZP and two porcelain veneers, IPS e.max Ceram and VITA VM9, were used in this study. Vita YZ zirconia blocks were sectioned and sintered to provide slabs of 1.65, 3.25, and 6.50mm in thickness. Two techniques were used to fabricate VITA VM9 and e.max Ceram porcelain veneer porcelain discs, Hand Layered, mixing powder with manufacturer’s molding liquid, condensed in a mold, and Pressed, pressing powder uniaxially in a mold. A layer of carbon paint was applied to the zirconia to allow removal of the porcelain discs. For thermal shock test the veneering porcelain fired on the Y-TZP core with a wash layer. After the veneer discs were fabricated, they were sintered: (1) According to the manufacturer’s instructions; (2) Two different cycles with slower heat rate and longer holding than the recommended value. Biaxial flexural strength was determined using a universal mechanical tester. Thermal shock tests were performed using a Pober thermal shock device. Statistical analysis was conducted for all tests using ANOVA and Tukey post hoc test at p= 0.05. RESULTS: There was significant effect from changes of YZ Core thickness, firing cycle, and veneer technique on the mechanical properties of porcelain veneer. The veneering technique had the largest impact on the mechanical properties of veneer porcelain followed by firing cycle, followed by YZ core thickness. In using different firing cycles with different heat rates and holding times, slowing the heating rate had more influence on the mechanical properties of veneer porcelain. In measuring the surface temperature of the Y-TZP/VITA VM9 assembly, the specimen surface temperature was coincidental with the furnace programmed firing cycle using a slower heating rate firing cycle. CONCLUSIONS Veneering technique, slower heat rate firing cycle, and Y-TZP core thickness have significant impact on veneering porcelain mechanical properties. / 2018-09-28T00:00:00Z

No description available.

Objetivo: comparar a qualidade do ajuste interno de três tipos de infra-estruturas cerâmicas e um tipo de infra-estrutura metálica, sistemas universalmente usados na confecção de coroas totais. Métodos: A partir de um preparo mestre de coroa total, 40 troquéis de gesso tipo IV foram obtidos e distribuídos randomicamente em quatro grupos (n = 10) a saber: Grupo In-Ceram, Grupo Procera, Grupo Empress 2 e Grupo Metal.. Após sua confecção, cada infra-estrutura foi cimentada individualmente sobre o troquél mestre, usando silicone de adição de ultra-baixa viscosidade para preencher o espaço entre a infra-estrutura e o preparo. Após a remoção das coroas, cada réplica foi pesada em balança de precisão e logo separadas nas porções correspondentes à interface parede cervical e interface parede ocluso-axial, sendo então pesadas separadamente, para posterior obtenção de seu volume. Resultados: Interface paredes do preparo/paredes da infra-estrutura: Neste computo geral, houve diferença estatística significativa (P < 0,0001) entre os grupos estudados. As principais diferenças quantitativas no volume da interface ocorreram entre o Grupo In-Ceram e os demais grupos. Interface paredes ocluso-axial do preparo/paredes ocluso-axial da infra-estrutura: Repete-se aqui, diferença estatística significativa entre os grupos estudados (P < 0,0001). Mantêm-se as principais diferenças quantitativas no volume da interface em relação ao Grupo In-Ceram. Interface parede cervical do preparo/parede cervical da infra-estrutura: Não houve diferença estatística significativa (P > 0,5) no volume da interface cervical entre os Grupos Metal (menor média) e In-Ceram, com este apresentando pequeno aumento no volume desta interface, comparado ao primeiro. Em relação ao Grupo Metal, o volume da interface cervical foi maior no Grupo Empress 2, seguido do Grupo Procera, ambos mostrando diferença estatística significativa no confronto com o Grupo Metal (P < 0,001 e P < 0,01 respectivamente). Não houve diferença estatística significativa (P > 0,05) entre os Grupos Procera e Empress 2. Conclusões: Exceto em relação à interface cervical, o Grupo In-Ceram mostou os melhores resultados, seguido do Grupo Metal, para o ajuste interno. Os Grupos Metal e In-Ceram apresentaram os melhores desempenhos no ajuste interno, para a interface cervical. Os resultados sugerem estas infra-estruturas como as mais confiáveis quanto ao ajuste interno dentre as testadas neste trabalho. / Objective: Compare the quality of the internal fit of three kinds of ceramic infrastructures and one kind of metal infrastructure, universally used systems for total crown moulding. Methods: Starting from the preparation of a total crown master, 40 dies made of gypsum plaster, kind IV, were obtained and distributed at random in four groups (n = 10) that is: In-Ceram group, Procera group, Empress 2 group and Metal group.. After moulding, each infrastructure was individually cemented on the master die, ultra-low viscosity silicon adhesive was used to fill in the space between the infrastructure and the preparation area. After crown removal each replicate was weighed on a precision scale and was then separated in parts corresponding to the cervical wall interface and the occluso-axial wall interface; they were then weighed separately to get their volume. Results: Walls interface of infrastructure preparation/walls: Within this general estimate a statistically significant difference (P < 0,0001) was found between the studied groups. The main quantitative differences on the interface volume occurred between the In-Ceram group and the other groups. Occluso-axial walls interface of the infrastructure occlusal-axial preparation/walls: Here again, a statistically significant difference between the studied groups (P < 0,0001) is present. Main quantitative differences on the interface volume remain in relation to the In-Ceram group. Cervical wall interface of the infrastructure cervical preparation/wall: No statistically significant difference was found (P > 0,5) on the cervical interface volume between the Metal groups (least average) and In-Ceram, the latter presenting a slight increase on the volume of this interface, when compared to the first one. In relation to the Metal group, the cervical interface volume was greater in the Empress 2 group, followed by the Procera group, both showing a statistically significant difference when compared to the Metal group (P < 0,001 e P < 0,01 respectively). No statistically significant difference (P > 0,05) was found between the Procera and Empress 2 groups. Conclusions: Except for the relation of the cervical interface, the In-Ceram group showed the best results, followed by the Metal group, for internal fit. The Metal and In-Ceram groups presented the best performance in the internal fit, for the cervical interface. The results obtained suggest that these infrastructures are the most reliable ones regarding the internal fit considering the ones tested in this work.

Objetivo: comparar a qualidade do ajuste interno de três tipos de infra-estruturas cerâmicas e um tipo de infra-estrutura metálica, sistemas universalmente usados na confecção de coroas totais. Métodos: A partir de um preparo mestre de coroa total, 40 troquéis de gesso tipo IV foram obtidos e distribuídos randomicamente em quatro grupos (n = 10) a saber: Grupo In-Ceram, Grupo Procera, Grupo Empress 2 e Grupo Metal.. Após sua confecção, cada infra-estrutura foi cimentada individualmente sobre o troquél mestre, usando silicone de adição de ultra-baixa viscosidade para preencher o espaço entre a infra-estrutura e o preparo. Após a remoção das coroas, cada réplica foi pesada em balança de precisão e logo separadas nas porções correspondentes à interface parede cervical e interface parede ocluso-axial, sendo então pesadas separadamente, para posterior obtenção de seu volume. Resultados: Interface paredes do preparo/paredes da infra-estrutura: Neste computo geral, houve diferença estatística significativa (P < 0,0001) entre os grupos estudados. As principais diferenças quantitativas no volume da interface ocorreram entre o Grupo In-Ceram e os demais grupos. Interface paredes ocluso-axial do preparo/paredes ocluso-axial da infra-estrutura: Repete-se aqui, diferença estatística significativa entre os grupos estudados (P < 0,0001). Mantêm-se as principais diferenças quantitativas no volume da interface em relação ao Grupo In-Ceram. Interface parede cervical do preparo/parede cervical da infra-estrutura: Não houve diferença estatística significativa (P > 0,5) no volume da interface cervical entre os Grupos Metal (menor média) e In-Ceram, com este apresentando pequeno aumento no volume desta interface, comparado ao primeiro. Em relação ao Grupo Metal, o volume da interface cervical foi maior no Grupo Empress 2, seguido do Grupo Procera, ambos mostrando diferença estatística significativa no confronto com o Grupo Metal (P < 0,001 e P < 0,01 respectivamente). Não houve diferença estatística significativa (P > 0,05) entre os Grupos Procera e Empress 2. Conclusões: Exceto em relação à interface cervical, o Grupo In-Ceram mostou os melhores resultados, seguido do Grupo Metal, para o ajuste interno. Os Grupos Metal e In-Ceram apresentaram os melhores desempenhos no ajuste interno, para a interface cervical. Os resultados sugerem estas infra-estruturas como as mais confiáveis quanto ao ajuste interno dentre as testadas neste trabalho. / Objective: Compare the quality of the internal fit of three kinds of ceramic infrastructures and one kind of metal infrastructure, universally used systems for total crown moulding. Methods: Starting from the preparation of a total crown master, 40 dies made of gypsum plaster, kind IV, were obtained and distributed at random in four groups (n = 10) that is: In-Ceram group, Procera group, Empress 2 group and Metal group.. After moulding, each infrastructure was individually cemented on the master die, ultra-low viscosity silicon adhesive was used to fill in the space between the infrastructure and the preparation area. After crown removal each replicate was weighed on a precision scale and was then separated in parts corresponding to the cervical wall interface and the occluso-axial wall interface; they were then weighed separately to get their volume. Results: Walls interface of infrastructure preparation/walls: Within this general estimate a statistically significant difference (P < 0,0001) was found between the studied groups. The main quantitative differences on the interface volume occurred between the In-Ceram group and the other groups. Occluso-axial walls interface of the infrastructure occlusal-axial preparation/walls: Here again, a statistically significant difference between the studied groups (P < 0,0001) is present. Main quantitative differences on the interface volume remain in relation to the In-Ceram group. Cervical wall interface of the infrastructure cervical preparation/wall: No statistically significant difference was found (P > 0,5) on the cervical interface volume between the Metal groups (least average) and In-Ceram, the latter presenting a slight increase on the volume of this interface, when compared to the first one. In relation to the Metal group, the cervical interface volume was greater in the Empress 2 group, followed by the Procera group, both showing a statistically significant difference when compared to the Metal group (P < 0,001 e P < 0,01 respectively). No statistically significant difference (P > 0,05) was found between the Procera and Empress 2 groups. Conclusions: Except for the relation of the cervical interface, the In-Ceram group showed the best results, followed by the Metal group, for internal fit. The Metal and In-Ceram groups presented the best performance in the internal fit, for the cervical interface. The results obtained suggest that these infrastructures are the most reliable ones regarding the internal fit considering the ones tested in this work.