Decellularized bone matrix-enriched 3D-printed GelMA scaffold as a cell-homing platform: analysis using an artificial pulp chamber model

The aim of the study was to develop and evaluate bio-printed hydrogels based on gelatin methacrylate (GelMA) combined with different proportions of decellularized bovine bone matrix microparticles (BMdc). GelMA hydrogels were synthesized and incorporated with decellularized bovine bone matrix (BMdc) at 1% by weight. 3D scaffolds were fabricated through extrusion, with varying infill densities (40%, 50%, and 60%), followed by photoactivation. Biological analyses included cell viability (Live/Dead assay), and proliferation (Alamar Blue assay), as well as osteogenic differentiation (ALP activity and Alizarin Red staining) over a 21-day period in HDPCs. Porosity and pore size were assessed with Rhodamine B staining, and cell migration to scaffolds was evaluated in a biomimetic artificial pulp chamber model. Data were analyzed with one-way ANOVA and Tukey’s test (p < 0.05). Scaffolds with the highest porosity and the largest pore size in comparison with other groups was detected in the 40% infill group (p < 0.05). Cells in the 50% and 60% infill groups exhibited higher viability, proliferation, and osteogenic differentiation, especially when BMdc particles were incorporated (p < 0.05). The greatest cell migration at the artificial pulp chamber model was observed in the 60% infill group in association with BMdc particles (p < 0.05). In summary, 3D-printed GelMA-BMdc hydrogel with 60% infill is a cytocompatible biomaterial capable of inducing cell adhesion, odontogenic differentiation, and mineralization. This innovative biomaterial shows potential for future direct pulp capping applications.