Influence of thermal expansion mismatch on residual stress profile in veneering ceramic layered on zirconia: Measurement by hole-drilling

摘要

Objectives. Mismatch in thermal expansion coefficient between core and veneering ceramic (Delta alpha = alpha(core) - alpha(veneer), ppm/degrees C) is reported as a crucial parameter influencing veneer fractures with Yttria-tetragonal-zirconia-polycrystal (Y-TZP) prostheses, which still constitutes a misunderstood problem. However, the common positive Delta alpha concept remains empirical. The objective of this study is to investigate the Delta alpha dependence of residual stress profiles in veneering ceramic layered on Y-TZP frameworks.