3D-Printed Auricular Scaffold Based on Porous UHMWPE Reinforced with PVA/CS Double-Network Hydrogel

Auricular reconstruction remains a significant challenge in tissue engineering due to the auricle’s complex anatomy and functional requirements. To address the limitations of autologous cartilage grafts, we developed a composite scaffold consisting of porous ultra-high molecular weight polyethylene (UHMWPE) integrated with a polyvinyl alcohol/chitosan (PVA/CS) double-network hydrogel reinforced with 2 wt% nano-hydroxyapatite (HA). The scaffold was fabricated via powder sintering and physical crosslinking and exhibited high porosity (>41%), a tensile strength of 2.80 MPa, and enhanced water retention. The addition of HA improved both the mechanical strength and antibacterial properties of the composite. The hydrogel component demonstrated stable swelling behavior, hemolysis rates below 5%, and good cytocompatibility. These findings demonstrate that the UHMWPE/PVA-CS/HA composite scaffold, combining the rigidity of a sintered porous framework with the flexibility and bioactivity of a reinforced hydrogel, offers a novel and promising platform for patient-specific auricular reconstruction with balanced mechanical, biological, and antibacterial properties.