RESUMO
Minimally invasive treatments are a dominant trend in dentistry. Due to the evolution of adhesive materials and ceramics, minimalistic ceramic restorations have been proposed as alternative treatment options to avoid unnecessary tooth reduction. The aim of this article is to show a clinical protocol for the correct diagnosis, treatment planning, and execution of minimally invasive ceramic veneers. Requiring only slight tooth preparation, this conservative technique is well-suited for restoration of teeth that need color and shape modification. The present clinical case demonstrates immediate success in restoring patient esthetics, function, and, in turn, self-esteem. After 2.5 years all veneers were still in exceptional condition and periodontal tissue was healthy. Minimally invasive ceramic restoration is shown to be an excellent option for conservative restorative treatment.
Assuntos
Porcelana Dentária , Restauração Dentária Permanente/métodos , Preparo do Dente/métodos , Adulto , Cimentos Dentários , Planejamento de Prótese Dentária , Feminino , HumanosRESUMO
O objetivo do presente estudo foi avaliar o efeito de diferentes tratamentos de superfície sobre a resistência de união de pinos de fibra ao canal radicular. Quarenta e quatro pré-molares inferiores humanos, recém-extraídos, foram instrumentados utilizando-se o sistema rotatório K3®. Os canais foram obturados com guta-percha e cimento Sealapex®. Após preparo para pino, foi realizado um dos quatro seguintes tipos de tratamento de superfície intrarradicular: irrigação com cloreto de sódio (NaCl) a 0,9%, hipoclorito de sódio (NaOCl) a 2,5%, digluconato de clorexidina (CHX) a 2% ou ácido etilenodiaminotetracético (EDTA) a 17%. Pinos de fibra foram cimentados utilizando-se o cimento resinoso RelyX® (Unicem). A partir da parte coronária de cada raiz, foram obtidas três fatias de 1mm de espessura. Foi realizado o teste de cisalhamento por extrusão (Push-out) utilizando uma máquina de ensaios universal a 0,5mm/min. Os dados obtidos foram tabulados e submetidos à análise estatística por meio da análise de variância e do teste de Tukey (p < 0,05). Os resultados mostraram que o tratamento com NaOCl ou EDTA aumentou a resistência de união à dentina, porém sem diferenças do ponto de vista estatístico. Foi possível concluir que a força de união do pino de fibra ao canal radicular não foi significantemente afetada pelo tratamento de superfície com NaOCl a 2,5%, CHX a 2% ou EDTA a 17%.
Assuntos
Pinos Dentários , Dentina , Ácido Edético , Endodontia , Materiais Restauradores do Canal Radicular , Tratamento do Canal Radicular , Cloreto de Sódio , Hipoclorito de SódioRESUMO
OBJECTIVES: The non-homogenous aspect of periodontal ligament (PDL) has been examined using finite element analysis (FEA) to better simulate PDL behavior. The aim of this study was to assess, by 2-D FEA, the influence of non-homogenous PDL on the stress distribution when the free-end saddle removable partial denture (RPD) is partially supported by an osseointegrated implant. MATERIAL AND METHODS: Six finite element (FE) models of a partially edentulous mandible were created to represent two types of PDL (non-homogenous and homogenous) and two types of RPD (conventional RPD, supported by tooth and fibromucosa; and modified RPD, supported by tooth and implant [10.00x3.75 mm]). Two additional Fe models without RPD were used as control models. The non-homogenous PDL was modeled using beam elements to simulate the crest, horizontal, oblique and apical fibers. The load (50 N) was applied in each cusp simultaneously. Regarding boundary conditions the border of alveolar ridge was fixed along the x axis. The FE software (Ansys 10.0) was used to compute the stress fields, and the von Mises stress criterion (svM) was applied to analyze the results. RESULTS: The peak of svM in non-homogenous PDL was higher than that for the homogenous condition. The benefits of implants were enhanced for the non-homogenous PDL condition, with drastic svM reduction on the posterior half of the alveolar ridge. The implant did not reduce the stress on the support tooth for both PDL conditions. CONCLUSION: The PDL modeled in the non-homogeneous form increased the benefits of the osseointegrated implant in comparison with the homogeneous condition. Using the non-homogenous PDL, the presence of osseointegrated implant did not reduce the stress on the supporting tooth.
Assuntos
Implantação Dentária Endóssea , Prótese Dentária Fixada por Implante , Prótese Parcial Removível , Análise de Elementos Finitos , Ligamento Periodontal/fisiologia , Fenômenos Biomecânicos , Dente Suporte , Humanos , Teste de Materiais , Modelos Biológicos , Reprodutibilidade dos Testes , Estresse MecânicoRESUMO
OBJECTIVES: The non-homogenous aspect of periodontal ligament (PDL) has been examined using finite element analysis (FEA) to better simulate PDL behavior. The aim of this study was to assess, by 2-D FEA, the influence of non-homogenous PDL on the stress distribution when the free-end saddle removable partial denture (RPD) is partially supported by an osseointegrated implant. MATERIAL AND METHODS: Six finite element (FE) models of a partially edentulous mandible were created to represent two types of PDL (non-homogenous and homogenous) and two types of RPD (conventional RPD, supported by tooth and fibromucosa; and modified RPD, supported by tooth and implant [10.00x3.75 mm]). Two additional Fe models without RPD were used as control models. The non-homogenous PDL was modeled using beam elements to simulate the crest, horizontal, oblique and apical fibers. The load (50 N) was applied in each cusp simultaneously. Regarding boundary conditions the border of alveolar ridge was fixed along the x axis. The FE software (Ansys 10.0) was used to compute the stress fields, and the von Mises stress criterion (svM) was applied to analyze the results. RESULTS: The peak of svM in non-homogenous PDL was higher than that for the homogenous condition. The benefits of implants were enhanced for the non-homogenous PDL condition, with drastic svM reduction on the posterior half of the alveolar ridge. The implant did not reduce the stress on the support tooth for both PDL conditions. Conclusion: The PDL modeled in the non-homogeneous form increased the benefits of the osseointegrated implant in comparison with the homogeneous condition. Using the non-homogenous PDL, the presence of osseointegrated implant did not reduce the stress on the supporting tooth.
Assuntos
Humanos , Implantação Dentária Endóssea , Prótese Dentária Fixada por Implante , Prótese Parcial Removível , Análise de Elementos Finitos , Ligamento Periodontal/fisiologia , Fenômenos Biomecânicos , Dente Suporte , Teste de Materiais , Modelos Biológicos , Reprodutibilidade dos Testes , Estresse MecânicoRESUMO
Tooth replacement in the maxillary anterior region is especially difficult when the loss includes significant amounts of the residual ridge and the soft tissue. Several techniques are available, such as dental implants or fixed partial denture, and bone and gingival grafts or gingival prostheses, respectively. This article showed a clinical case of an elderly who was treated with a collarless metal-ceramic fixed partial denture and acrylic removable gingival prosthesis to recover the esthetics in the maxillary anterior region. The association of a metal-ceramic fixed denture and gingival prosthesis was an excellent alternative in cases when surgical procedures are contraindicated.
Assuntos
Prótese Dentária , Prótese Parcial Fixa , Estética Dentária , Gengiva , Maxila , Acrilatos , Idoso , Feminino , HumanosRESUMO
OBJECTIVES: Based on a maxillary premolar restored with laminate veneer and using the 3-D finite element analysis (FEA) and µCT data, the aim of this study was to evaluate the influence of different types of buccal cusp reduction on the stress distribution in the porcelain laminate veneer and in the resin luting cement layer. METHODS: Two 3-D FEA models (M) of a maxillary premolar were built from µCT data. The buccal cusp reduction followed two configurations: Mt - buccal cusp completely covered by porcelain laminate veneer; and Mp - buccal cusp partially covered by porcelain laminate veneer. The loading (150 N in 45°) was performed on the top of the buccal cusp. The finite element software (Ansys Workbench 10.0) was used to obtain the maximum shear stress (τ(max)) and maximum principal stress (σ(max)). RESULTS: The Mp showed reduced the stress (σ(max)) in porcelain laminate veneer (from -2.3 to 24.5 MPa) in comparison with Mt (from -5.3 to 27.4 MPa). The difference between the peak and lower stress values of σ(max) in Mp (-6.8 to 26.7 MPa) and Mt (-5.3 to 27.4 MPa) was similar for the resin luting cement layer. The structures not exceeded the ultimate tensile strength or the shear bond strength. CONCLUSIONS: Cusp reduction did not affect significant increase in σ(max) and τ(max). The Mt showed better stress distribution (τ(max)) than Mp.
Assuntos
Dente Pré-Molar/fisiologia , Porcelana Dentária , Facetas Dentárias , Análise de Elementos Finitos , Colagem Dentária , Análise do Estresse Dentário , Humanos , Cimentos de Resina , Estresse Mecânico , Resistência à TraçãoRESUMO
A reposição das perdas dentárias, antes limitadas ao uso de próteses convencionais, atualmente, podem ser feitas por próteses implantossuportadas. Com a aplicação dos conceitos de planejamento reverso, é possível obter resultados protéticos satisfatórios, tendo uma previsão dos insucessos que podem ocorrer durante o tratamento. Assim, através de um caso clínico, o presente artigo tem como objetivo demonstrar a associação de duas técnicas de retenção de prótese implantossuportada, associada ao planejamento reverso, para a resolução de um caso de falha estética e funcional do conjunto implante-prótese. Paciente do sexo feminino, 63 anos, portando no arco superior uma prótese do tipo protocolo e no arco inferior uma prótese parcial removível Classe I, modificação 2 de Kennedy. A queixa principal da paciente era o constante mau cheiro e a estética precária de ambas as próteses. O plano de tratamento estabelecido foi a confecção de duas próteses tipo protocolo, sendo a inferior imediata e a superior uma associação de prótese cimentada e parafusada. Após a resolução do plano de tratamento, todos os anseios da paciente foram alcançados, recuperando estética, função e sorriso.
In the past, treatment of tooth loss was limited to the use of conventional total prostheses. Nowadays, the use of implant-supported prostheses has brought new horizons. It is possible to provide satisfactory esthetic results according to a reverse planning philosophy. Through a clinical case, the present article aims to demonstrate the association of two retention techniques for the resolution of aesthetic and functional drawbacks in both maxillary arches. A female 63 years-old patient presented with her maxillary total implant-supported prosthesis and mandibular conventional removable prosthesis (Kennedy´s Class I, modification 2). Her main complaints were oral malodor and unacceptable aesthetics. For this, screw-cemented (hybrid) and immediate prostheses were provided in the maxillary and mandibular arches. Thus, esthetics, function, and smile were improved to achieve all patient´s desires.
Assuntos
Humanos , Feminino , Adulto , Implantes Dentários , Prótese Dentária Fixada por Implante , Reabilitação BucalRESUMO
O objetivo do presente estudo foi avaliar através do método dos elementos finitos tridimensional (3D FEA), o comportamento mecânico de uma faceta laminada de cerâmica e do cimento resionoso em um 1o pré-molar maxilar, variando a redução (parcial ou total) da cúspide vestibular. Material e método: Baseado em imagens micro-tomográficas (μCT) 2 modelos (M) tridimensionais foram construídos no programa Solidworks 2007 variando a redução da cúspide vestibular, sendo Mp o modelo composto pelo dente pré-molar restaurado com uma faceta laminada de cerâmica, com redução parcial da cúspide vestibular e Mt, o modelo semelhante ao Mp, porém com redução total da cúspide vestibular. O programa de elementos finitos ANSYS Workbench 10.0 foi utilizado para realizar as análises. O carregamento (150 N) foi aplicado próximo à ponta de cúspide vestibular, com 45º de inclinação. Foram utilizados os critérios da máxima tensão principal ( max) e da máxima tensão cisalhante ( shear) na faceta laminada e na camada de cimento resinoso. Resultados: O Mt mostrou menor shear em 9 das 12 áreas analisadas quando comparado ao Mp. O Mp mostrou menor variação da max (de -3,13 para 14,4 MPa) que o Mt para a lâmina de cerâmica (de -2,08 para 24,3 MPa) A camada de cimento apresentou variação de max semelhante entre os Mp e Mt. Os critérios de tensões utilizados não evidenciaram valores além dos limites estabelecidos para a falha estrutural do material estudado. Conclusão: O laminado cerâmico e a camada de cimento resinoso apresentaram comportamento mecânico favorável para a restauração do pré-molar frente ao carregamento adotado. O tipo de redução de cúspide não influenciou no aumento expressivo das tensões principal e cisalhante. O Mp apresentou menores valores de max em tração quando comparado ao Mt. O Mp e o Mt apresentaram comportamento favorável com relação as forças cisalhantes, sendo as maiores tensões encontradas no modelo Mp
Objectives: Using 3-D finite element analysis (FEA) and μCT data, the aim of this study was to evaluate the behavior of the laminate veneer and the resin luting cement in a maxillary premolar with the buccal cusp partially or completed covered. Material and method: 2 3-D FEA models of a maxillary premolar were built from μCT data. All models were restored with a feldspathic laminate veneer using Solidworks. A similar tooth reduction (0.5mm) was applied for two models. The buccal cusp reduction of the premolar followed two configurations: Model (Mt) - buccal cusp completely covered by veneer; and Model (Mp) - buccal cusp partially covered by veneer. The loading (150N, in 45o) was performed on the buccal cusp of each premolar. Appropriate boundary condition was applied at the periodontal ligament surfaces and ANSYS (10.0) was used to obtain the maximum shear stress ( shear) and maximum principal stress ( max) for the laminate veneer and resin luting cement layer. Results: The Mp showed higher shear than Mt in 9 to 12 analyzed areas. The Mp showed smallest variation of max in laminate veneer (from -3,13 to 14,4 MPa) compared with Mt (from - 2,08 to 24,3 MPa). The resin luting cement showed similar variation of max between Mp and Mt (from -3.13 to 12.2 MPa) and (from -1.61 to 14.1 MPa), respectively. None of the structures exceeded the ultimate tensile strength or the shear bond strength to dentin and enamel. Conclusion: The laminate veneer and the resin luting cement layer showed an adequate behavior when veneer was applied in premolars. Cusp reduction did not affect significant increase in max and shear. In general, the Mp showed better behavior ( max) than Mt. The Mt showed better behavior ( shear) than Mp
Assuntos
Porcelana Dentária , Facetas Dentárias , Estética Dentária , Análise de Elementos FinitosRESUMO
O objetivo do presente estudo foi avaliar através do método dos elementos finitos tridimensional (3D FEA), o comportamento mecânico de uma faceta laminada de cerâmica e do cimento resionoso em um 1o pré-molar maxilar, variando a redução (parcial ou total) da cúspide vestibular. Material e método: Baseado em imagens micro-tomográficas (μCT) 2 modelos (M) tridimensionais foram construídos no programa Solidworks 2007 variando a redução da cúspide vestibular, sendo Mp o modelo composto pelo dente pré-molar restaurado com uma faceta laminada de cerâmica, com redução parcial da cúspide vestibular e Mt, o modelo semelhante ao Mp, porém com redução total da cúspide vestibular. O programa de elementos finitos ANSYS Workbench 10.0 foi utilizado para realizar as análises. O carregamento (150 N) foi aplicado próximo à ponta de cúspide vestibular, com 45º de inclinação. Foram utilizados os critérios da máxima tensão principal ( max) e da máxima tensão cisalhante ( shear) na faceta laminada e na camada de cimento resinoso. Resultados: O Mt mostrou menor shear em 9 das 12 áreas analisadas quando comparado ao Mp. O Mp mostrou menor variação da max (de -3,13 para 14,4 MPa) que o Mt para a lâmina de cerâmica (de -2,08 para 24,3 MPa) A camada de cimento apresentou variação de max semelhante entre os Mp e Mt. Os critérios de tensões utilizados não evidenciaram valores além dos limites estabelecidos para a falha estrutural do material estudado. Conclusão: O laminado cerâmico e a camada de cimento resinoso apresentaram comportamento mecânico favorável para a restauração do pré-molar frente ao carregamento adotado. O tipo de redução de cúspide não influenciou no aumento expressivo das tensões principal e cisalhante. O Mp apresentou menores valores de max em tração quando comparado ao Mt. O Mp e o Mt apresentaram comportamento favorável com relação as forças cisalhantes, sendo as maiores tensões encontradas no modelo Mp.
Objectives: Using 3-D finite element analysis (FEA) and μCT data, the aim of this study was to evaluate the behavior of the laminate veneer and the resin luting cement in a maxillary premolar with the buccal cusp partially or completed covered. Material and method: 2 3-D FEA models of a maxillary premolar were built from μCT data. All models were restored with a feldspathic laminate veneer using Solidworks. A similar tooth reduction (0.5mm) was applied for two models. The buccal cusp reduction of the premolar followed two configurations: Model (Mt) - buccal cusp completely covered by veneer; and Model (Mp) - buccal cusp partially covered by veneer. The loading (150N, in 45o) was performed on the buccal cusp of each premolar. Appropriate boundary condition was applied at the periodontal ligament surfaces and ANSYS (10.0) was used to obtain the maximum shear stress ( shear) and maximum principal stress ( max) for the laminate veneer and resin luting cement layer. Results: The Mp showed higher shear than Mt in 9 to 12 analyzed areas. The Mp showed smallest variation of max in laminate veneer (from -3,13 to 14,4 MPa) compared with Mt (from - 2,08 to 24,3 MPa). The resin luting cement showed similar variation of max between Mp and Mt (from -3.13 to 12.2 MPa) and (from -1.61 to 14.1 MPa), respectively. None of the structures exceeded the ultimate tensile strength or the shear bond strength to dentin and enamel. Conclusion: The laminate veneer and the resin luting cement layer showed an adequate behavior when veneer was applied in premolars. Cusp reduction did not affect significant increase in max and shear. In general, the Mp showed better behavior ( max) than Mt. The Mt showed better behavior ( shear) than Mp.
Assuntos
Porcelana Dentária , Facetas Dentárias , Estética Dentária , Análise de Elementos FinitosRESUMO
Introdução: A utilização de próteses bucomaxilofaciais são deextrema importância para a reintegração no convívio social dospacientes acometidos de deformidades congênitas ou adquiridas.Usualmente a retenção destes aparelhos protéticos é realizadacom o uso de sistemas adesivos, no entanto é necessário areaplicação deste componente químico no decorrer de suautilização, pois sua adesão esta sujeita a interferências de fatorescomo transpiração, oleosidade da tez do paciente, assim comofatores externos como clima e temperatura, além de poder gerarirritação tecidual ao paciente. Com o desenvolvimento dos implantesosseointegrados, novas possibilidades de tratamento se tornarampossíveis pela inserção de pilares de suporte para as prótesesbucomaxilofaciais associadas a sistemas de retenção, fornecendomaior estabilidade e retenção dos aparelhos protéticos que autilização de sistemas adesivos, propiciando maior conforto esegurança aos pacientes, tendo influência direta no aumento daauto-estima dos mesmos.Objetivo: Apresentar uma revisão de literatura a respeito dostipos de implantes e sistemas de retenção para as prótesesbucomaxilofaciais, auxiliando o protesista na indicação e seleçãocorreta do conjunto de sistemas mais adequados para cada casoclínico.Conclusão: Os implantes utilizados nas...
Assuntos
Implantes Dentários , Retenção em Prótese Dentária , Prótese MaxilofacialRESUMO
The bond strength of composite resins (CRs) to dentin is influenced by the interfacial microstructure of the hybrid layer (HL) and the resin tags (TAG). The contemporary self-etching primer adhesive systems overcame the inconvenient of the etch-and-rinse protocol. Studies, however, have demonstrated that HL thickness and TAG length vary according to the wetting time and additional use of acid-etching prior to self-etching primers. This study investigated the localized stress distribution in the HL and the dentin/adhesive interface. Two HL thicknesses (3 or 6 mum), two TAG lengths (13 or 17 mum) and two loading conditions (perpendicular and oblique-25°) were investigated by the finite element (FE) analysis. Five two-dimensional FE models (M) of a dentin specimen restored with CR (38 x 64 mum) were constructed: M1 - no HL and no TAG; M2 - 3 mum of HL and 13 ìm of TAG; M3 - 3 mum of HL and 17 mum of TAG; M4 - 6 mum of HL and 13 mum of TAG; and M5 - 6 mum of HL and 17 mum of TAG. Two distributed loadings (L) (20N) were applied on CR surface: L1 - perpendicular, and L2 - oblique (25°). Fixed interfacial conditions were assigned on the border of the dentin specimen. Ansys 10.0 (Ansys®, Houston, PA, USA) software was used to calculate the stress fields. The peak of von Mises (sigmavM) and maximum principal stress (sigmamax) was higher in L2 than in L1. Microstructures (HL and TAG) had no effect on local stresses for L1. Decreasing HL decreased sigmavM and sigmamax in all structures for L2, but the TAG length had influence only on the peributular dentin. The thickness of HL had more influence on the sigmavM and sigmamax than TAG length. The peritubular dentin and its adjacent structures showed the highest sigmavM and sigmamax, mainly in the oblique loading.
RESUMO
The bond strength of composite resins (CRs) to dentin is influenced by the interfacial microstructure of the hybrid layer (HL) and the resin tags (TAG). The contemporary self-etching primer adhesive systems overcame the inconvenient of the etch-and-rinse protocol. Studies, however, have demonstrated that HL thickness and TAG length vary according to the wetting time and additional use of acid-etching prior to self-etching primers. This study investigated the localized stress distribution in the HL and the dentin/adhesive interface. Two HL thicknesses (3 or 6 microm), two TAG lengths (13 or 17 microm) and two loading conditions (perpendicular and oblique-25 degrees) were investigated by the finite element (FE) analysis. Five two-dimensional FE models (M) of a dentin specimen restored with CR (38 x 64 microm) were constructed: M1 - no HL and no TAG; M2 - 3 microm of HL and 13 microm of TAG; M3 - 3 microm of HL and 17 microm of TAG; M4 - 6 microm of HL and 13 microm of TAG; and M5 - 6 microm of HL and 17 microm of TAG. Two distributed loadings (L) (20N) were applied on CR surface: L1 - perpendicular, and L2 - oblique (25 masculine). Fixed interfacial conditions were assigned on the border of the dentin specimen. Ansys 10.0 (Ansys, Houston, PA, USA) software was used to calculate the stress fields. The peak of von Mises (sigma(vM)) and maximum principal stress (sigma(max)) was higher in L2 than in L1. Microstructures (HL and TAG) had no effect on local stresses for L1. Decreasing HL decreased sigma(vM) and sigma(max) in all structures for L2, but the TAG length had influence only on the peributular dentin. The thickness of HL had more influence on the sigma(vM) and sigma(max) than TAG length. The peritubular dentin and its adjacent structures showed the highest sigma(vM) and sigma(max), mainly in the oblique loading.
RESUMO
O tratamento reabilitador com implantes em áreas estéticas tem atualmente um alto índice de sucesso clínico. No entanto não existe um protocolo definido para esta modalidade de tratamento resabilitador. Em virtude desse fato, a literatura apresenta certas divergências sobre qual seria a melhor técnica ou material a ser utilizado nesse tratamento reabilitador, o que torna essa modalidade estauradora um desafio para o cirurgião-dentista. Assim sendo, este trabalho abrange os aspectos cirúrgicos, protéticos e os requisitos estéticos de análise do sorriso