Biomimetic 3D-Printed Resorbable Extracellular Matrix-Guided Bone Regeneration Membrane Based on a Gelatin Methacrylate/Alginate-Hydroxyapatite Composite for Maxillofacial Surgery

Guided bone regeneration (GBR) membranes that prevent fibroblast infiltration while promoting new bone formation are critically needed in maxillofacial surgery. In this study, a 3D-printed, resorbable GBR membrane inspired by bone extracellular matrix (ECM) components was developed using gelatin methacrylate (GelMA), alginate (Alg), and hydroxyapatite (HA) at 0, 20, 40, and 60%, denoted as GelMA/Alg, GelMA/Alg20HA, GelMA/Alg40HA, and GelMA/Alg60HA, respectively. Morphological features were examined by scanning electron microscopy and 3D profilometry, and mechanical properties, surface wettability, swelling behavior, and degradation profiles were systematically evaluated. Structural and thermal characteristics were analyzed by X-ray diffraction, Fourier-transform infrared spectroscopy, and differential scanning calorimetry. Biological performance was assessed using MC3T3-E1 osteoblasts on the bone-facing side and L929 fibroblasts on the soft-tissue side. Barrier efficacy was evaluated through fibroblast occlusion assays, and osteogenic potential was determined by total protein content and alkaline phosphatase (ALP) activity. Furthermore, osteoconductive and stem cell-regulating abilities were investigated using human bone marrow stromal cells (hBMSCs) under dynamic culture conditions. The addition of HA enhanced filament alignment, surface wettability, mechanical strength, and structural stability, forming porous structures conducive to bone integration and dense surfaces that effectively inhibited fibroblast infiltration. Among all groups, GelMA/Alg20HA exhibited the most balanced mechanical, biological, and barrier performance, highlighting its potential as a resorbable GBR membrane for maxillofacial bone regeneration.