Influence of different water types on the physical and mechanical properties of gypsum

• Published in: Brazilian journal of oral sciences 2015-09, Vol.14 (3), p.199-203
• Main Authors: Proença, Juliana dos Santos, Suzuki, Marcos Massahiro, Costa, Silvano Cesar da, Hirata, Bruno Shindi, Lopes, Murilo Baena, Contreras, Edwin Fernando Ruiz
• Format: Article
• Language: English
• Subjects: DENTISTRY, ORAL SURGERY & MEDICINE
• ISSN: 1677-3225; 1677-3225
• DOI: 10.1590/1677-3225v14n3a05

Abstract Aim: To evaluate if gypsum mixed with different water types, with their different compositions influence the dimensional change, surface roughness and compressive strength of type IV and V gypsum specimens. Methods: Sixty specimens were fabricated from metal matrices and divided into six groups (n=10) according to the used type of gypsum and water: G1, G2 and G3 - type IV gypsum and tap, mineral and distilled water, respectively; G4, G5 and G6 - type V gypsum and tap, mineral and distilled water, respectively. Water/powder ratio followed the manufacturer's recommendations (19 mL/100 g) in all groups. The same specimens were used for all tests. A micrometer dial evaluated the dimensional change. The surface roughness of three random points was determined with a rugosimeter; a universal testing machine performed the compressive strength test. The data were subjected to analysis of variance (ANOVA). Results: There was no statistically significant difference (p>0.05) between the three types of water in the studied variables. There was statistically significant difference (p