Author(s): Sahoo, Narayan ; Carvalho, Oscar ; Özcan, Mutlu ; Silva, Filipe ; Lasagni, Andrés-Fabian ; Henriques, Bruno
Date: 2024
Persistent ID: https://hdl.handle.net/1822/92650
Origin: RepositóriUM - Universidade do Minho
Subject(s): DLIP; Adhesion; 3Y-TZP
Zirconia (3Y-TZP) is a highly valued material in dentistry due to its exceptional mechanical strength, biocompatibility, and aesthetic appeal, making it ideal for crowns, bridges, and implants. However, achieving strong adhesion to zirconia is challenging because of its chemical inertness and low surface energy, which prevent effective bonding with traditional dental cements[1-3]. This study evaluated the impact of short-pulse direct laser interference patterning (DLIP) and combined direct laser writing with DLIP (DLW + DLIP) on the shear bond strength (SBS) of dental-grade zirconia with resin-matrix cements. Compared to Direct Laser Writing (DLW), which creates patterns point-by-point and is less efficient for large areas, DLIP offers significant advantages. Zirconia compacts underwent two DLIP patterns: DLIPp (parallel lines) and DLIPc (crossed lines), and two hybrid patterns combining DLW35 (squared lines, 35 μm spacing) with DLIP. The control group used only DLW35. DLIP can precisely modify the zirconia surface to enhance roughness and create micro- and nanoscale features over large areas simultaneously, significantly improving mechanical interlocking and chemical bonding with cements. Treated samples were cleaned, cemented with resin-matrix cement, and tested for SBS after 24 hours at 37ºC or thermocycling (5-55ºC, 6000 cycles). Surface roughness was highest in DLW35. The hybrid DLW+DLIPc group showed the highest SBS in dry conditions (25.39 ± 7.74 MPa), while the control group showed the lowest (8.49 ± 2.02 MPa). Both DLIP groups and hybrid groups exhibited significantly higher SBS, even after thermocycling, compared to DLW alone. These advancements in laser technology address the adhesion challenges, ensuring the durability and success of zirconia-based dental restorations.
