Zirconia (ZrO₂) implants have shown promising outcomes in the restoration of tooth loss. However, the discrepancy between the elastic modulus of ZrO₂ implants and alveolar bone can cause a stress shielding effect at the bone-implant interface, leading to progressive damage and possibly resulting in the clinical failure of the implant treatment. Functionally graded porous implants present a promising solution to this issue. Triply periodic minimal surfaces (TPMS) have attracted growing interest for their ability to create 3D interconnected and continuous pore structures. Dental implants, especially around the neck region, experience both compressive and tensile stresses in bone. ZrO₂, being a brittle material, is more susceptible to tensile stress than compressive stress, making flexural strength a critical property for evaluating its performance. The objective of this research is to assess the flexural properties, biological performance, and permeability of gradient sheet-network TPMS zirconia specimens printed by vat photopolymerization (VPP). In vitro evaluations of the biological properties revealed that the Schwarz-P structure had the most significant effects in promoting the proliferation of rat bone marrow stem cells (rBMSCs) and enhancing the expression of osteogenic-related genes. However, it also exhibited the lowest flexural strength and permeability. In contrast, Diamond structure displayed good flexural strength, structural stability, and effectively promoted osteogenic-related gene expression, presenting a well-balanced combination of mechanical and biological properties. This suggests its potential for further development into 3D-printed functional gradient ZrO₂ implants.