Influence of glass-ceramic thickness on Hertzian and bulk fracture mechanisms.

Abstract

The authors conclude that bulk fracture is initiated within the bonded surface of a glass-ceramic specimen (for samples 0.4 to 2.4 mm in thickness) when the glass-ceramic is supported by a substrate with an elastic modulus similar to that of dentin. Furthermore, a Hertzian failure mechanism is unlikely to cause bulk fracture for these conditions.