Universidad Autónoma de Ciudad Juárez Departamento de estomatología. Yeso parís o Yeso Blanco Alumna. Medina Hernández Brianda Isidra Dr. Alfredo Nevárez Rascón
Is a fragile plaster which is obtained by heating gypsum at 110 ° c, is used for castingstudy models, has a strength of 450 kg per cm2 Fig. 2 Ground gypsum http://upload.wikimedia.org/wikipedia/commons/ a/a7/Calcium_sulfate_hemihydrate.jpg
Plaster of paris is also called: Fig.3•Gypsum Modelo de yeso tipo II•Snow White.•Gypsum plaster•White Plaster•Type II. http://es.ruthinium.it/dentadura-postiza/productos/plasters/
This is the most used in dentistry, is used for mounting on articulator and prosthesis Fig. 4 Prosthesis model made with plaster paris. http://www.evolucionodontologica.com/?cat=17&paged=2
Common plaster Yeso of París o Type II Lime plaster Cement plaster Fig.5 Cement plaster. http://materialdental.blogspot.com/2011/02/yes os-de-uso-dental.html
All have the same chemical formula. They have different physical properties. All they are derived from same material The main difference is the way to eliminate some of the water gave hydrated sulfate. You can also use synthetic gypsum to manufacture some products but are less popular because of its high cost.
The water is placed in a plastic cup. Powder is added. Allowed to stand in water for about 30 seconds. It minimizes the amount of air that is incorporated into the mixture during the mixing. Perform the mixing with a rigid sheet metal spatula. The manual consists spatula stir the mixture vigorously. Properly mix to obtain a uniform mixture, rubbing in circular motions and try to dissolve any lumps and to wet the entire mixture
In dental use is found as:Calcium Sulfate CaSO4 · H2O.And when mixed with water :CaSO2· 2H2O Fig.6 Calcium Sulfate http://fyq4eso.blogspot.com/feeds/posts/default
optimal immobilization Dirty apply. Moldable. Takes to set. Cheap. Voluminous. No loss of volume. Heavy. Do not wet.