Improving Zirconia–Resin Cement Bonding Through Laser Surface Texturing: A Comparative Study

Objectives: This study evaluates the effectiveness of laser surface texturing (LST) using a Surface Transition Machine (STM) on pre-sintered zirconia, comparing its impact on surface characteristics and shear bond strength (SBS) with resin cement to conventional sandblasting techniques. Methods: Zirconia specimens were treated with either STM or sandblasting, followed by surface analysis through scanning electron microscopy (SEM) and White Light Interferometry (WLI), wettability assessment via contact angle measurements, and SBS testing with resin cement and a 10-MDP-containing primer. Results: SEM and WLI revealed significant surface alterations in STM-treated zirconia, producing microscale textures. STM-treated surfaces exhibited significantly lower contact angles (28.4 ± 10.0°) compared to untreated (78.2 ± 8.0°) and sandblasted (79.2 ± 5.7°) surfaces, indicating enhanced wettability (p < 0.05). SBS was highest in the STM with primer group (46.3 ± 8.3 MPa) and STM without primer (43.4 ± 4.3 MPa), both of which significantly outperformed sandblasting with primer (30.06 ± 3.09 MPa) and sandblasting alone (9.8 ± 3.7 MPa) (p < 0.05). Conclusions: These findings suggest that STM-based LST is a more effective method for improving zirconia surface characteristics and adhesion in dental restorations, simplifying bonding procedures, and potentially offering better clinical outcomes than conventional sandblasting.