Mechanical, Surface and Physicochemical Properties of Nanozeolite‐Modified 3D Printed Hybrid Ceramics at Varying Concentrations: An In Vitro Study

ABSTRACT Objectives To evaluate nanozeolite (NZ)‐modified 3D‐printed hybrid ceramics at 0.25%, 0.5%, and 1% versus milled hybrid resin‐ceramics, focusing on fracture toughness, surface roughness, microhardness, degree of conversion (DC), water sorption, and color stability. Materials and Methods NZ was incorporated into 3D‐printed ceramic‐filled resin (VarseoSmile Crown Plus, VA) and tested alongside unmodified VA (control) and milled CAD‐CAM ceramic (Vita Enamic, VE). Bars (18 × 3.6 × 1.8 mm) were prepared for fracture toughness, and discs (10 × 2 mm) for roughness, microhardness, water sorption, and color/translucency. Fracture toughness was measured by the single‐edge notched beam (SENB) method, roughness and microhardness by profilometer and Vickers test, and DC by FTIR. Water sorption/solubility was gravimetrically measured, and ΔE00 and translucency parameter (TP) by spectrophotometry. Tests were conducted before and after thermocycling (1000 cycles, 5°C–55°C). Data were analyzed using ANOVA, Kruskal‐Wallis, t‐tests, and Wilcoxon signed‐rank tests ( p < 0.05). Results VE exhibited the highest fracture toughness and microhardness, which decreased after thermocycling ( p < 0.001). NZ‐0.25% improved toughness versus VA both before and after aging ( p = 0.04), while NZ‐0.5% and 1% slightly reduced toughness but increased microhardness and decreased roughness after aging ( p < 0.01). All NZ groups showed higher DC than control ( p < 0.001). Thermocycling reduced toughness in VE and VA, but not NZ‐VA. Water sorption and solubility were significantly lower in all NZ groups ( p < 0.0001). ΔE00 remained < 1.8 for all groups after thermocycling, with 0.25% NZ‐VA showing the most color stability and 1% NZ‐VA showing minimal TP changes ( p < 0.05). Conclusion Milled hybrid ceramic (VE) outperformed printed hybrid ceramic (VA). Nanozeolite improved VA, with 0.25% providing the best balance of fracture toughness and microhardness, while preserving color and aging stability. Higher concentrations (0.5%–1%) mainly enhanced surface characteristics but added little to bulk properties and translucency. Clinical Significance Nanozeolite integration at 0.25% enhances strength, durability, and color stability in 3D‐printed hybrid ceramics, improving their reliability for dental restorations. Higher loadings enhance surface properties but may modestly reduce bulk toughness and translucency, relevant for clinical decision‐making.