Effect of shelf life on compressive strength of type iv gypsum

[摘要] Type IV gypsum, as a dental material for an indirect restoration's working model, should have strength and abrasive-resistant properties. These properties depend on the product's shelf life and its proper storage, which sometimes are easily missed by sellers. The aim of this research was to observe the effect of shelf life on the compressive strength of type IV gypsum with different production dates. Twenty cylindrical specimens were separated into two groups with different production dates and tested with a universal testing with the crosshead speed of 1 mm per minute and a load of 2,500 kgf. The data were analyzed with independent t-tests. There was a significant difference (p

[发布机构] Department of Dental Materials, Faculty of Dentistry, Universitas Indonesia, Jakarta, Indonesia^1

[效力级别] 医药卫生 [学科分类] 卫生学

[关键词] Crosshead speed;Cylindrical specimens;Shelf life;T-tests;Working models