Multi-Printhead Parallel Printing of Polycaprolactone Barrier/Filler-Integrated Scaffolds for Alveolar Bone Repair

Most current guided bone regeneration (GBR) procedures rely on manual assembly of membranes and filler materials during surgery, which often results in reduced shape fidelity, potential loss or displacement of graft powder, decreased operational efficiency and consistency. Here, we propose a multi-printhead parallel printing strategy for the fabrication of barrier/filler-integrated GBR scaffolds for alveolar bone repair by upgrading a conventional melt extrusion-based printing system with a parallelized 10-printhead module. Compared with conventional single-printhead system, the parallel 10-printhead configuration introduces thermal crosstalk, elevating local temperatures near the building platform and hindering the proper solidification of printed structures. By implementing cooling convection via fans and temperature compensation, we achieved simultaneous printing of 10 thin-wall membrane structures with consistent geometry and interlayer-bonding strength. Moreover, the system enables parallel printing of triply periodic minimal surface (TPMS) porous structures and barrier/filler-integrated GBR scaffolds, substantially enhancing overall manufacturing efficiency. In vivo studies using a rabbit alveolar defect model further demonstrated that the parallel-printed integrated scaffolds effectively prevented soft tissue invasion while promoting robust bone regeneration, achieving outcomes superior to those of clinically established GBR strategies. The proposed multi-printhead parallel printing technique offers a scalable, efficient way to mass-produce clinically applicable polymeric implants.