ABSTRACT
This study analyzed the reaction layer and measured the marginal crown fit of cast titanium applied to different phosphate-bonded investments, prepared under the following conditions (liquid concentration/casting temperature): Rema Exakt (RE) - 100 percent/237°C, 75 percent/287°C, Castorit Super C (CS)-100 percent/70°C, 75 percent/141°C and Rematitan Plus (RP)- 100 percent/430°C (special to titanium cast, as the control group). The reaction layer was studied using the Vickers hardness test, and analyzed by two way ANOVA and Tukey's HSD tests (á = 0.05). Digital photographs were taken of the crowns seated on the die, the misfit was measured using an image analysis system and One-way ANOVA, and Tukey's test was applied (á = 0.05). The hardness decreased from the surface (601.17 VHN) to 150 ìm (204.03 VHN). The group CS 75 percent/141°C presented higher hardness than the other groups, revealing higher surface contamination, but there were no differences among the groups at measurements deeper than 150 ìm. The castings made with CS - 100 percent/70°C presented the lowest levels of marginal misfit, followed by RE -100 percent/237°C. The conventional investments CS (100 percent) and RE (100 percent) showed better marginal fit than RP, but the CS (75 percent) had higher surface contamination.
Subject(s)
Crowns , Dental Marginal Adaptation , Dental Casting Investment/chemistry , Phosphates/chemistry , Titanium/chemistry , Analysis of Variance , Dental Casting Technique , Dental Materials , Hardness Tests , Hot Temperature , Materials Testing , Surface PropertiesABSTRACT
Esse estudo avaliou o efeito da tecnica de inclusao de revestimentos fosfatados nafluidez, rugosidade de superficie, camada de reacao (α-case) e adaptacao marginal de copings fundidos em Ti cp. Os padroes foram incluidos de forma convencional ou pela tecnica de inclusao experimental, na qual os padroes foram cobertos comRematitan Ultra RU previamente a inclusao. Os revestimentos fosfatados estudados foram: Rematitan Plus (RP), Rema Exakt (RE), Castorit Super C (CA) e o revestimento a base de espinelio Rematitan Ultra (RU) foi o grupo controle. Sete grupos experimentais foram constituidos: G1: RU (controle); G2: RP; G3: RP e RU; G4: RE; G5: RE e RU; G6: CA; G7: CA e RU. Para fluidez foram feitos corpos-de-prova quadrados (15 mm X 15 mm X 0.3 mm) e a area (mm2) foi medida por um sistema analisador de imagens (n=8). Para a rugosidade de superficie as medidas (Ra) foram feitas em rugosimetro Mitutoyo (Mitutoyo SJ 400, Kanagawa, Japan) em corpos-de-prova quadrados (12 mm x 12 mm x 2 mm) n =8. A camada de reacao foi analisada por dureza Vickers, micro-analise por energia dispersiva (EDX), microscopia optica e a composicao dos revestimentos. Para dureza Vickers as medidas foram feitas em corpos-de-prova cilindricos (obtidos a partir dos sprues fundidos nos copos-de-prova para o teste de fluidez) em profundidades de 25, 50, 100, 150, 200 e 300Wm da superficie para o centro, em durometro Micromet 2100 (Buehler, Lake Bluff, Illinois, EUA) n= 8. Para a micro-analise por energia dispersiva (EDX) um equipamento EDX LINK ANALYTICAL, modelo QX 2000, com microscopio eletronico LEO (Zeiss - Germany) e detector OXFORD (Oxford Instrumentos de nano-analises Halifax Alta Rotacao WycombeBucks-HP12 3SE, UK) foram feitas em tres areas da camada de reacao (25 Wm, 75Wm e 150 Wm). Para a microscopia optica, as amostras foram polidas e limpas com solucao acida de Kroll por 20 segundos e observadas em Microscopio...
This study evaluated the effect investing technique with phosphate-bonded investment on the castability, surface of roughness, reaction layer (α-case) and marginal coping fit of CP titanium. For all analysis the specimen were coated with Rematitan Ultra - RU (experimental technique), previously to the inclusion (conventional technique) and invested into the phosphate-bonded investments: Rematitan Plus (RP), Rema Exakt (RE), Castorit Super C (CA). The seven groups studied were: G1: RU (control), G2: RP; G3: RP and RU; G4: RE; G5: RE and RU; G6: CA; G7: CA and RU. For castability, square patterns (15 mm X 15 mm X 0.3 mm) were made. The castability area (mm2) was measured by an image analysis system (n=8). The surface roughness was measured (Ra) with a rugosimeter Mitutoyo (Mitutoyo SJ 400, Kanagawa, Japan) in square resin patterns (12 mm x 12 mm x 2 mm) n =8. The reaction layer was analyzed by Vickers hardness, Energy Dispersive X-ray microanalysis (EDX), optical microscopy and the investments composition were studied by X ray diffraction (XRD). The Vickers hardness measurements were made sprue of castability test in cross section at depths of 25, 50, 100, 150, 200 and 300Wm from the surface to the interior, using a durometer Micromet 2100 (Buehler, Lake Bluff, Illinois, EUA) n= 8. For Energy Dispersive X-ray microanalysis (EDX) was used an equipment EDX Link Analytical, model QX 2000, with Microscopy Electronic LEO (Zeiss - Germany) with detector Oxford (Oxford Instruments-Nano Analysis Halifax Road High WycombeBucks-HP12 3SE, UK) in three areas of reaction layer (25 Wm, 75Wm e 150 Wm). For the optical microscopy the samples were polished, cleaned and acid etched with the Kroll solution for 20 seconds and observed in an optical microscope Quimis (200 X) attached to an image analyzer Leika Qwin. For the study of the investments composition, samples with...
Subject(s)
Dental Casting Investment , Dental Casting Technique , TitaniumABSTRACT
Uma das etapas primordiais para o sucesso de uma reabilitação por meio de prótese fixa sobre implante é a moldagem, pois busca-se obter sempre uma adaptação precisa e passiva entre a plataforma do implante e o componente protético. Essa adaptação garantirá aintegridade do tecido ósseo e das estruturas adjacentes ao implante, frente a isso o objetivo desse artigo foi revisar e esclarecer algumas dúvidas sobre as técnicas de moldagem empregadas para a obtenção do modelo de trabalho o mais fiel possível para a confecção da prótese fixa sobre implante.
One of the main steps for the success of the implant supported prostheses is the impression technique because the accuracy to fit and the passivity of the cast metal framework are important. This fit will guarantee the health of the tissue/titanium interface and adjacent structures. Thus, the aim of this study was to review and elucidate some doubts about the impression techniques used to obtain a more accurate master cast fabrication for implant supported prostheses.