Hybrid TiO2/Al2O3 nanolayer overcoating enhances dental lithium disilicate glass-ceramics acid resistance and surface mechanical properties

Abstract Lithium disilicate glass-ceramics are increasingly utilized in dental applications due to their exceptional optical and aesthetic properties. However, lithium disilicate glass-ceramics possess a mixed crystalline and amorphous structure with variable resistance to external corrosion. Exposure of lithium disilicate glass-ceramics to acidic conditions in the oral cavity leads to pore formation, and the risk of cracking increases with long-term wear. Herein, we employed atomic layer deposition to precisely coat the TiO 2 /Al 2 O 3 hybrid nanolayer on the surface of lithium disilicate glass-ceramics to enhance acid resistance and surface mechanical properties. The TiO 2 species play crucial roles in improving acid resistance, and the Al 2 O 3 species, atomically bonded to the TiO 2 species in the hybrid layer, promote interfacial interactions. Moreover, the TiO 2 /Al 2 O 3 hybrid nanolayer shows no cytotoxicity while maintaining the aesthetics of lithium disilicate glass-ceramic restorations, thus offering broad prospects for oral restoration applications.