Abstract
This study investigated ways to reduce the time reguired for dental casting.The properties of commercial gypsum bonded dental investments used in the quick heating method were tested.In comparison with a conventional cristobalite gypsum bonded investment, the properties obtained in the tested materials included:good fluidity, large dimensional changes during setting, thermal expansion because of quartz and cristobalite content, small thermal expansion values, and green strength ranging from 1.6-4.3MPa.There was approximately a 300℃ discrepancy between measuring points in the investment at quick heating.However, the surface of castings obtained using investments for quick heating were sound.For accurate casting, further studies are necessary, for example, concerning the start time of heating.
