Study of gypsum-bonded casting investments. Part 2.
The simultaneous differential thermal analysis--thermogravimetry (DTA-TG) method used in Part 1 of this two-part study was extended to analyse two gypsum-bonded dental casting investments, Kerr Cristobalite Inlay and GC Cristobalite Micro. Both investments had a similar cristobalite content of about 70 per cent. The remaining 30 per cent was dental stone in GCM, and a mixture of plaster and dental stone in KCl. Inclusion of plaster in KCl appeared responsible for the greater amount of water required for mixing this investment. The DTA-TG method used in the present study can be applied to identify the type and amount of hemihydrate, and the type of silica, in currently available gypsum-bonded investments.
McAloon
J
J
Department of Prosthetic Dentistry, Faculty of Dentistry, University of Sydney.
Mori
T
T
D002133:Calcium Sulfate; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003734:Dental Casting Investment / Q000737:chemistry*; D004055:Differential Thermal Analysis; D006358:Hot Temperature; D008422:Materials Testing; D012822:Silicon Dioxide; D013818:Thermogravimetry; D014867:Water
D003734:Dental Casting Investment; D014867:Water; D012822:Silicon Dioxide; D002133:Calcium Sulfate