Retention Strength of Polyetheretherketone Crowns Vs. Zirconia Crowns Restoring Molar Teeth: An in Vitro Study

This study was designed to compare the retention strength of monolithic CAD/CAM PEEK crowns that YTZP-zirconia crowns, both resin-cemented epoxy resin dies resembling lower molar teeth; after thermomechanical aging simulating 3 months in-vivo service. Materials and methods: 22 identical dies, preparation a second (4mm height, 6° axial convergence 1 mm-thick deep chamfer finish line), were produced by replicating one master stainless steel die via polyvinyl siloxane impressions. The randomly equally distributed into 2 groups (Zr P groups); 11 each. first (control) group (Zr) received milled Y-TZP zirconia (Katana™ ML), while other (intervention) (breCAM.BioHPP™). Two opposing, laterally projecting (mesial distal) arms included in design all for test. fitting surfaces sandblasted with 110-µm alumina particles.