Microstructure, composition, and flexural strength of different layers within zirconia materials with strength gradient.

Objectives: The aim of this study was to compare composition, microstructure, and mechanical strength of current multilayer zirconia blanks.

Methods: Bar shaped specimens were made from several layers of multilayer zirconia blanks (Cercon ht ML, Dentsply Sirona, US; Katana Zirconia YML, Kuraray, J;SHOFU Disk ZR Lucent Supra, Shofu, J; priti multidisc ZrO Multi Translucent, Pritidenta, D; IPS e.max ZirCAD Prime, Ivoclar Vivadent, FL).