Aim: To evaluate the efficacy of sulfuric acid treatment of PEEK's surface on the shear bond strength to veneering composite compared to air abrasion.
Methodology: 20 disc-shaped samples (10 mm diameter - 2 mm thickness) were produced from breCAM BioHPP blank and were randomly and equally divided into 2 groups according to the surface treatment; group H2So4: treatment with 98% sulfuric acid (etching), group Al2O3: treatment with 110 μm aluminum oxide particles (air abrasion). Visio-link primer was applied to samples followed by Crea.lign veneering composite. Scanning electron microscope (SEM) was used for the measurement of surface roughness. Universal testing machine was used to perform the shear bond strength (SBS) test. Elemental analysis was done after surface treatment and after shear bond strength test using energy dispersive X-ray analysis (EDX).
Results: Statistical analysis showed that group Al2O3 (30.26 ± 3.97 μm) had significantly higher surface roughness than group H2So4 (22.95 ± 2 μm). While group H2So4 (11.72 ± 2.93 MPa) had significantly higher shear bond strength than group Al2O3 (9.07 ± 1.63 MPa). Elemental analysis showed increase in sulfur and oxygen in group H2So4 and increase in carbon and silica in group Al2O3.
Conclusion: 98% sulfuric acid surface treatment of PEEK enhances SBS more than aluminium oxide air blasting.