Effects of Various Laser Treatments on Surface Characterization and Repair Bond Strength of Zirconia-Reinforced Lithium Silicate Ceramics.

This study evaluates the effects of two lasers—erbium: yttrium-aluminum-garnet (Er: YAG) and neodymium: yttrium-aluminum-garnet (Nd: YAG)—and their combination with hydrofluoric acid (HF) etching on the surface roughness and shear bond strength (SBS) of zirconia-reinforced lithium silicate (ZLS) ceramics bonded to composite resin. Results showed that Nd: YAG laser alone or combined with HF produced significantly higher SBS values compared to Er: YAG laser treatments, with no significant difference between Nd: YAG and HF etching alone. The study suggests Nd: YAG laser or its combination with HF as effective intraoral repair methods for ZLS ceramics, noting that HF etching is more cost-effective but may pose safety concerns, whereas laser use offers a safer alternative for patients and clinicians.