Effect of phosphate-bonded investments on titanium reaction layer and crown fit

• Autor(a) principal: Rocha,Sicknan Soares da
• Data de Publicação: 2010
• Outros Autores: Nogueira,Fabiane, Pieralini,Anelise Rodolfo Ferreira, Ribeiro,Ricardo Faria, Adabo,Gelson Luis
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Oral Research
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1806-83242010000200004
• topic: Dental casting investment; Dental alloys; Titanium; Dental casting technique; Dental prosthesis

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%/237°C, 75%/287°C, Castorit Super C (CS)-100%/70°C, 75%/141°C and Rematitan Plus (RP)- 100%/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 (α = 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 (α = 0.05). The hardness decreased from the surface (601.17 VHN) to 150 μm (204.03 VHN). The group CS 75%/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 μm. The castings made with CS - 100%/70°C presented the lowest levels of marginal misfit, followed by RE -100%/237°C. The conventional investments CS (100%) and RE (100%) showed better marginal fit than RP, but the CS (75%) had higher surface contamination.