An Analytical Model to Predict the Effects of Heating Rate and Applied Load on Glass Transition Temperatures of Dental Porcelain

Abstract

An analytical model was developed to predict the effects of heating rate and load on the glass transition temperature (Tg) of dental porcelain. An equation similar to the Moynihan equation relating heating rate to T_g was found for midspan load. The validity of the analytical model was demonstrated by using viscosity data from one published study to predict Tg behavior in an independent study. Values of Tg calculated with the analytical model for a dilatometer specimen were found to be higher than T_g values calculated for a bending beam viscometer.

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