Evaluation of the shear bond and bi-axial flexural strength of zircona core veneered by CAD/CAM and PRESS-ON technique
The aim of this in vitro study is to compare the shear bond and bi-axial flexural strengths of samples veneered with, CAD/CAM-fabricated zirconia core, and Press-on technique, with the definition its mode of failure.
Twenty zirconia core discs were made using IPs e.max ZirCAD and CAD/CAM technology. These were divided equally in to two groups. Group one was veneered by CAD-on technique using IPs e.max CAD, and group two was veneered by Press-on technique using IPs e.max ZirPress, then all the discs are thermocycled. The specimens were exposed to shear bond and biaxial flexural strength testing. Mode of failure was evaluated by SEM. All data were collected and analyzed statistically by SPSS, with significance level 5%, where P≤ 0.05. The t- test analysis of shear strength test showed statistically significant difference at (p < 0.05) for CAD-on group. While there were no statistically significant difference at (p < 0.05) for the biaxial flexural strength test between the two groups. CAD-on group showed adhesive/cohesive failure, while press-on group showed cohesive failure within the veneering ceramic. This study concluded that, the bond strength between zirconia core and veneer was affected by the veneering technique. CAD-on technique showed statistically significant high bond strength over Press-on technique arabic 20 English 98
Seham Ali Elsawaay*, Milad Mustafa Eshah, Mohamed Al basher Zeglam(1-2018)