Viscoelastic stress analysis of thermally compatible and incompatible metal–ceramic systems

Significance. Currently there are no U.S. or international standards that define the maximum difference in thermal contraction coefficients that can exist between a metal and its ceramic veneer without causing transient failures of ceramic during cooling or delayed failures in ceramic because of high residual tensile stresses. The present research represents a major step in understanding the various factors that influence the development of transient and residual stresses. A knowledge of the effects of process variables on stress development is necessary for selection of potentially successful metal–ceramic systems and for optimizing the design of dental prostheses.