Evaluation of the Effect of Various Surface Treatment Methods on Shear Bond Strength between Zirconia Post and Composite Resin Core Material: An In-Vitro Study

Introduction: In the prosthetic rehabilitation of the maxillary anterior region, zirconia restorations are frequently used. Aim: To evaluate the shear bond strength between zirconia post and composite resin core material with different surface treatment. Material and Methods: Total 80 samples of sintered zirconia blocks (5mm X 5mm X 2mm) were fabricated for this study. These zirconia blocks were fixed on acrylic block and four different groups were made on basis of surface treatment. Group 1 (G1) no surface treatment, Group II (G2): Laser etching with Er: YAG laser, Group III (G3): Internal coating (INT) with silica based porcelain, Group IV (G4): Aluminium nitride nano particles. After surface treatment, zirconia primer was applied over surface treated zirconia specimen. Composite resin blocks were fabricated with help of glass mold measuring 5mm X 5mm X 2mm and luted with same composite material over zirconia block. Shear bond strength was measured by universal testing machine at across head speed of 1mm per minute. Surface of each specimen was observed under Stereomicroscope and two specimen of each test group were evaluated under Scanning electron microscope. Data was analyzed using Tukey Test and Dunnett D Test. Results: The mean shear bond strength obtained was 1.62 MPa with control group, 2.99 MPa, 2.80 MPa and 4.91 MPa with laser group, internal coating group and Aluminium nitride group respectively. Conclusion: All the surface treatment methods in the study enhanced the shear bond strength between zirconia and composite resin when compared with the control group. Surface treatment with Aluminium nitride nano particle showed highest mean shear bond strength.