Background: Pulp necrosis in immature permanent teeth halts root development, producing thin dentinal walls and increasing fracture risk. Conventional apexification can create an apical barrier but does not reliably support continued root maturation. This study aimed to fabricate a two-region hydrogel scaffold using continuous extrusion-based three-dimensional (3D) printing and assess it with cone-beam computed tomography (CBCT).
Methods: This is a laboratory feasibility study. A simulated immature root canal was prepared in an extracted human tooth and assessed using CBCT. The measured root length and minimum canal diameter served as anatomical references for scaffold dimensions. The scaffold consisted of an alginate–carboxymethyl chitosan (CMC) region and an alginate- nominal 45S5 bioactive glass region. Both formulations were sequentially loaded into a single cartridge and extruded through one nozzle without post-printing assembly. Six fabrication attempts were made, of which 5 attempts met the operational criteria of full layer deposition, preserved gross configuration, and visible continuity between regions. Therefore, five completed scaffolds underwent qualitative macroscopic evaluation during printing, crosslinking, washing, handling, and biopsypunch preparation.
Results: The constructs displayed two distinguishable yet continuous material regions. No gaps, fragmentation, delamination, collapse, or separation were observed after crosslinking, washing, or preparation of 50 punched specimens (2–5 mm diameter).
Conclusion: Continuous extrusion through one cartridge and nozzle enables fabrication of a compositionally differentiated two-region hydrogel scaffold with preserved macroscopic continuity. Further quantitative architectural, mechanical, degradation, and biological evaluations are required to determine functional significance.