Composite powder design strategy enabling vat photopolymerization 3D printing of lithium disilicate glass-ceramics with high precision, strength, and antibacterial properties

Lithium disilicate glass-ceramic is a widely used dental restoration material, valued for its aesthetic semi-translucency, high strength, and excellent biocompatibility. Vat photopolymerization, a form of 3D printing, presents a transformative alternative to the conventional powder sintering and machining of this material, offering significant improvements in production efficiency and material utilization. However, 3D printing lithium disilicate glass-ceramics is challenging, primarily due to severe light scattering caused by their high transparency, which compromises printing accuracy. This study proposes a functional composite powder design strategy, which incorporates carbon and zinc oxide powders into the lithium disilicate matrix, based on light scattering principles. Through optical simulations and experimental validation, the composition was rationally optimized to produce functional dental prostheses with high precision, strength, and antibacterial properties. Carbon confines light scattering via its high extinction coefficient, and zinc oxide secures adequate curing depth via its high refractive index, synergistically ensuring high precision. This work lays a foundation for advancing the 3D printing and clinical application of functional lithium disilicate glass-ceramics.