Loading...
Publication
Fundo metálico em restaurações provisórias, como solucioná-los?
| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 3.49 MB | Adobe PDF |
Advisor(s)
Abstract(s)
Objetivo: Analisar as variações de cor de um compósito a base de PMMA de diversas espessuras provocadas pelo seu emparelhamento com dois substratos metálicos (cromocobalto e titânio).
Materiais e Métodos: Foram obtidas 40 amostras fabricadas com 0,5, 0,8, 1 e 2 mm de espessura, 10 amostras de cada, na cor 2M2T, a partir de um bloco de compósito a base de PMMA para uso em restaurações provisórias de longa duração VITA CAD-Temp® monocolor (VITA Zahnfabrik, Bad Säckingen, Alemanha). Para garantir uma rugosidade de superfície uniforme, essas amostras foram polidas com uma lixa de SiC (carbeto de silício) 500, 1000 e 1500 grãos. Como substrato metálico, foram utilizadas quarenta
amostras metálicas em cromo-cobalto e em titânio com 2 mm de espessura. As amostras de compósito foram analisadas por um espetrofotómetro VITA Easyshade® V (VITA Zahnfabrik, Bad Säckingen, Alemanha) contra um fundo cinza. Após esta leitura, as amostras de compósito foram aleatoriamente emparelhadas com as amostras metálicas.
As coordenadas de cor foram obtidas e a fórmula (ΔE*ab) utilizada para calcular a diferença de cor. Uma análise estatística ANOVA de duas vias com comparações múltiplas pelo método de Bonferroni foi realizada, com um intervalo de confiança a 95%.
Resultados: Apenas dois valores de (ΔE*ab) não apresentaram diferenças estatísticas significativas. A espessura de 2 mm contra o substrato em titânio foi a única a apresentar resultado clinicamente aceitável.
Conclusões: Os substratos metálicos afetam a cor final de uma restauração de forma distinta, sendo que o titânio apresentou melhor desempenho do que o cromo-cobalto. Quanto maior a espessura de um material maior a sua capacidade em mascarar o substrato ao qual será aderido.
Objective: To analyse the colour variations of a PMMA-based composite of different thicknesses caused by its pairing with two metallic substrates (cobalt chromium and titanium). Materials and Methods: 40 fabricated samples of 0.5, 0.8, 1 and 2 mm thickness, 10 samples of each, in shade 2M2T, were obtained from a block of PMMA-based composite for use in long-term provisional restorations VITA CAD-Temp® single-colour (VITA Zahnfabrik, Bad Säckingen, Germany). To ensure uniform surface roughness, these samples were polished with 500, 1000 and 1500 grit SiC (silicon carbide) sandpaper. Forty 2 mm thick cobalt-chromium and titanium metal samples were used as the metal substrate. The composite samples were analysed by a spectrophotometer VITA Easyshade® V (VITA Zahnfabrik, Bad Säckingen, Germany) against a gray background. After this reading, the composite samples were randomly paired with the metal samples. The colour coordinates were obtained and the formula (ΔE*ab) used to calculate the colour difference. A two-way ANOVA statistical analysis was carried out with multiple comparisons using the Bonferroni method, with a 95% confidence interval. Results: Only two values of (ΔE*ab) showed no statistically significant differences. The 2 mm thickness against the titanium substrate was the only one to show a clinically acceptable result. Conclusions: Metal substrates affect the final colour of a restoration differently, with titanium performing better than cobalt-chromium. The greater the thickness of a material, the greater its ability to mask the substrate to which it will be adhered.
Objective: To analyse the colour variations of a PMMA-based composite of different thicknesses caused by its pairing with two metallic substrates (cobalt chromium and titanium). Materials and Methods: 40 fabricated samples of 0.5, 0.8, 1 and 2 mm thickness, 10 samples of each, in shade 2M2T, were obtained from a block of PMMA-based composite for use in long-term provisional restorations VITA CAD-Temp® single-colour (VITA Zahnfabrik, Bad Säckingen, Germany). To ensure uniform surface roughness, these samples were polished with 500, 1000 and 1500 grit SiC (silicon carbide) sandpaper. Forty 2 mm thick cobalt-chromium and titanium metal samples were used as the metal substrate. The composite samples were analysed by a spectrophotometer VITA Easyshade® V (VITA Zahnfabrik, Bad Säckingen, Germany) against a gray background. After this reading, the composite samples were randomly paired with the metal samples. The colour coordinates were obtained and the formula (ΔE*ab) used to calculate the colour difference. A two-way ANOVA statistical analysis was carried out with multiple comparisons using the Bonferroni method, with a 95% confidence interval. Results: Only two values of (ΔE*ab) showed no statistically significant differences. The 2 mm thickness against the titanium substrate was the only one to show a clinically acceptable result. Conclusions: Metal substrates affect the final colour of a restoration differently, with titanium performing better than cobalt-chromium. The greater the thickness of a material, the greater its ability to mask the substrate to which it will be adhered.
Description
Dissertação para obtenção do grau de Mestre no Instituto Universitário Egas Moniz
Keywords
Habilidade de mascaramento CAD/CAM Restauração provisória Substrato escurecido