OICC Press Progress in Biomaterials 2194-0517 14 04 2025 12 30 Bioactive Photo-crosslinkable GelMA Hydrogel Incorporating Metal Oxide Nanoparticles for Bone Tissue Regeneration 10.57647/pibm.2025.1403.18 EN Lígia Espoliar Corrêa Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo (USP), Alameda Dr. Octávio Pinheiro Brisolla, 9-75, Bauru, São Paulo, 17012-901, Brazil Ester Alves Ferreira Bordini Department of Dental Materials and Prosthodontics, Ribeirão Preto School of Dentistry, University of São Paulo (USP), Av. do Café - Subsetor Oeste - 11 (N-11), Ribeirão Preto, São Paulo, 14040-904, Brazil Vitor de Toledo Stuani Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo (USP), Alameda Dr. Octávio Pinheiro Brisolla, 9-75, Bauru, São Paulo, 17012-901, Brazil Larissa Álamo Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo (USP), Alameda Dr. Octávio Pinheiro Brisolla, 9-75, Bauru, São Paulo, 17012-901, Brazil Ruan Henrique Delmonica Barra Department of Diagnosis and Surgery, School of Dentistry of Araçatuba, São Paulo State University (Unesp), Street José Bonifácio, 1193 - Vila Mendonca, Araçatuba, São Paulo, 16015-050, Brazil Erika Soares Bronze-Uhle Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo (USP), Alameda Dr. Octávio Pinheiro Brisolla, 9-75, Bauru, São Paulo, 17012-901, Brazil Laura Ferreira Almeida Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo (USP), Alameda Dr. Octávio Pinheiro Brisolla, 9-75, Bauru, São Paulo, 17012-901, Brazil Lídia de Oliveira Fernandes Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University (Unesp), Street Humaitá, 1680 - Araraquara, São Paulo, 14801-385, Brazil Carolina Alves Andrade Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo (USP), Alameda Dr. Octávio Pinheiro Brisolla, 9-75, Bauru, São Paulo, 17012-901, Brazil Juliano Milanezi de Almeida Department of Diagnosis and Surgery, School of Dentistry of Araçatuba, São Paulo State University (Unesp), Street José Bonifácio, 1193 - Vila Mendonca, Araçatuba, São Paulo, 16015-050, Brazil Carlos Alberto de Souza Costa Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University (Unesp), Street Humaitá, 1680 - Araraquara, São Paulo, 14801-385, Brazil Diana Gabriela Soares Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo (USP), Alameda Dr. Octávio Pinheiro Brisolla, 9-75, Bauru, São Paulo, 17012-901, Brazil https://orcid.org/0000-0002-1485-6104 Journal Article 2025 12 30 This study aimed to develop a photo-crosslinkable and 3D-printable biomaterial, comprising methacrylated gelatin (GelMA) functionalized with magnesium oxide (MgO) and silicon dioxide (SiO2) nanoparticles, as a bioactive scaffold for bone regeneration. Cytocompatible concentrations of MgO and SiO2 were identified using a dose-response assay, and selected formulations were characterized in terms of structural architecture, chemical composition, and cumulative nanoparticle release. Murine calvarial preosteoblasts were seeded onto hydrogels to evaluate long-term viability, proliferation, collagen expression, and mineralized matrix deposition. The formulations were also assessed for extrusion-based 3D printability. MgO and SiO2 at 0.05% and 0.025% (w/v) were used, which positively modulated the GelMA porosity. No chemical modifications to GelMA were detected; instead, the nanoparticles were gradually released. Cell viability was maintained in all groups over 14 days, with enhanced proliferation observed from day 3 onward. All oxide-functionalized GelMA formulations showed increased collagen expression and calcium-rich matrix deposition, with the 0.05% group inducing the greatest mineralization at 14 days. Well-organized 3D-printed meshes were successfully obtained, demonstrating that the combination of bioactivity and high printability can be leveraged for the development of personalized bone therapies. GelMA containing 0.05% MgO and SiO2 exhibited the highest osteogenic activity, representing the most promising platform for bone-tissue regeneration.