Retention of zirconium oxide ceramic crowns with three types of cement

摘要: Statement of problem Information about the retentive strength luting agents for zirconium oxide–based crowns is limited. It unknown if this type high-strength ceramic restoration requires adhesive cementation to enhance retention. Purpose The purpose in vitro study was determine ability selected retain a representative oxide crown under clinically simulated conditions. Material and methods Recently extracted human molars were prepared with flat occlusal surface, 20-degree taper, approximately 4-mm axial length. surface areas determined, specimens distributed equally by total area into 3 groups (n=12). Zirconium copings (Procera AllZirkon) an bar facilitate removal fabricated using computer-aided design/computer-assisted manufacturing (CAD/CAM) technology. All airborne-particle abraded 50-μm Al 2 O then cleaned ultrasonic bath isopropyl alcohol. Provisional cement removed from teeth, followed pumice prophy. After trial insertion, phosphoric acid, rinsed, dried, dehydrated They cemented seating force 10 kg per tooth, either composite resin agent (Panavia F 2.0 ED Primer A & B [PAN]), resin-modified glass ionomer (Rely X Luting [RXL]), or self-adhesive modified Unicem [RXU]). thermal cycled at 5°C 55°C 5000 cycles 15 second dwell time, along path insertion universal testing machine 0.5 mm/min. recorded, stress dislodgement calculated each preparation. 1-way analysis variance used analyze data (α=.05). nature failure also recorded. Results Mean stresses 5.1, 6.1, 5.0 MPa PAN, RXL, RXU, respectively. revealed no differences mean among groups. predominant mode remaining principally on 46% specimens, found tooth 25.7% specimens. Conclusions Within limitations study, agents, ranging 6.1 not significantly different. use bonding did yield higher coping retention compared other cements tested.