Influência do tempo de armazenamento na rugosidade, tração diametral e compressão de gessos odontológicos

• Ano de defesa: 2013
• Autor(a) principal: Cesero, Leonardo de
• Orientador(a): Mota, Eduardo Gonçalves
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul
• Programa de Pós-Graduação: Programa de Pós-Graduação em Odontologia
• Departamento: Faculdade de Odontologia
• País: BR
• Palavras-chave em Português: ODONTOLOGIA; MATERIAIS DENTÁRIOS; RESISTÊNCIA DOS MATERIAIS (ODONTOLOGIA)
• Área do conhecimento CNPq: CNPQ::CIENCIAS DA SAUDE::ODONTOLOGIA
• Link de acesso: http://tede2.pucrs.br/tede2/handle/tede/1193

The post pouring time to remove dental stone from impression is controversial regardless to strength and roughness. The aim of this study was evaluate the influence of post pouring time in the surface roughness, compressive and diametral tensile strength (DTS) of type IV dental stone. Two hundred and seventy dental stone samples were made from three commercial brands (Durone, Fuji Rock and Tuff Rock). Surface roughness, compressive and diametral tensile strength tests were performed 1 hour, 24 hours and 7 days after pouring. Samples of 6 mm in diameter and 3 mm in height were produced for roughness and DTS tests. Samples of 3 mm in diameter and 6 mm in height were used for compressive strength. Results were submitted to the general linear model and Tukey test (α=0.05). The surface roughness (Ra) registered to different types of dental stone vary from 0.30 μm (Durone 1 hour) to 0.64 μm (Tuff Rock 7 days). The diametral tensile strength (MPa) ranged from 3.94 (Tuff Rock 1 hour) to 9.20 (Durone 7 days). For compressive strength (MPa), data vary from 26.67 MPa (Durone 1 hour) to 65.14 MPa (Fuji Rock 7 days). There was a significant increase of surface roughness (p=0.005), diametral tensile strength (p=0.001) and compressive strength (p=0.001) as time passes after pouring. Commercial brand factor influenced roughness (p=0.001), diametral tensile strength (p=0.004) and compressive strength (p=0.001). Tuff Rock showed the highest surface roughness. The highest DTS was recorded for Durone and Fuji Rock. Fuji Rock showed the highest compressive strength.