3D-Printed and Bioprinted Scaffolds in Regenerative Endodontics: A Systematic Review

Introduction: Three-dimensional (3D) bioprinting is a promising approach for endodontic tissue engineering, enabling scaffolds with controlled architecture and bioactivity to support pulp regeneration. Objectives: This systematic review assessed the following: “What 3D bioprinting applications are reported in endodontics-related studies?” Materials and Methods: Following PRISMA 2020 guidelines, PubMed/MEDLINE, Scopus, Embase, Cochrane Library, Web of Science, SciELO, LILACS, and Google Scholar were searched up to January 2026 with no date or language limits. Two reviewers independently screened studies; risk of bias in in vitro studies was assessed with the QUIN tool. As only one study reported complete antimicrobial outcomes, an intra-study quantitative comparison (MD, 95% CI) of inhibition halos was performed (not a meta-analysis). Results: From 518 records, nine studies were included. Outcomes mainly addressed physicochemical properties (n = 9), cell viability (n = 7), biocompatibility (n = 5), and cell differentiation (n = 5); antimicrobial activity was evaluated in two studies. Most used hDPSCs and extrusion-based printing, testing calcium silicate composites, alginate hydrogels, functionalized PCL, and modified PLA. Modified PLA scaffolds showed greater antimicrobial activity, strongest with naringin and nHA formulations. Overall risk of bias was moderate (58.33%), largely due to limited reporting of randomization, blinding, and sampling. Conclusion: 3D-bioprinted scaffolds/bioinks generally improved cellular responses and bioactivity, especially with MTA, Biodentine, nHA, or naringin; antimicrobial effects were most evident in functionalized PLA (PLA/NAR and PLA/nHA/NAR).