Workflow for highly porous resorbable custom 3D printed scaffolds using medical grade polymer for large volume alveolar bone regeneration

Abstract

Objectives This study investigates the design, workflow, and manufacture of highly porous, resorbable additively manufactured, 3‐dimensional (3D) custom scaffolds for the regeneration of large volume alveolar bone defects. Materials and Methods Computed tomography (CT) scans of 5 posterior mandibular vertical bone defects were obtained. Surface masks (3D surface contours) of the recipient site were first isolated using a contrast threshold, transformed into 3D objects, and used to guide the formation of custom implant template models. To determine model accuracy and fit, the gap and overlap between the patient geometry models and the idealized template 3D models were quantified. Models were 3D printed from medical grade polycaprolactone (PCL) into porous scaffolds. For scaffold dimensional quantification, scaffolds were scanned using a micro‐computed tomography (µCT) scanner. Results The design and printing processes each achieved dimensional errors of <200 µm on average. The average gap between the template implant model and the scanned scaffold model was found to be 74 ± 14 µm. The printed scaffold was confirmed as having a porosity of 83.91%, a mean polymer or filament thickness of 200 ± 46 µm, and a mean pore size of 590 ± 243 µm. Conclusion The approach described in this study is straightforward, adaptable to a range of patient geometries, and results in the formation of reproducible, dimensionally accurate custom implants. These highly porous 3D structures manufactured from resorbable medical grade material represent a potentially transformative technology toward the clinical implementation of scaffold‐guided bone regeneration procedures.

Regenerative Medicine Technologies to Treat Dental, Oral, and Craniofacial Defects

“…Contemporary biomedical research is steadily approaching a reliable AM strategy to create bioresorbable bone scaffolds for clinical use and the implications for patient care are enormous. Recently, a workflow for AM fabrication of porous, bioresorbable scaffolds consisting of medical grade PCL for the reconstruction of large, posterior mandibular defects was demonstrated (Bartnikowski et al, 2020). The resultant porosity (83.91%) and mean pore size (590 ± 243 µm) were within suitable ranges for bone regeneration and the mean discrepancy between the template implant model and the scanned scaffold was found to be 74 ± 14 µm, representing a level of accuracy adequate for clinical application.…”

Additive Manufacturing of Material Scaffolds for Bone Regeneration: Toward Application in the Clinics

“…Indeed, the minimum accuracy required for bone tissue engineering depends on the pore size that is printed but dimensional errors of less than 200 µm are considered as satisfying (Table 3). [ 144 ] For example, the dimensional accuracy of SLS and inkjet printing is ±0.3 mm while it is ±0.1 mm for DMLS, SLM, and EBM (according to 3D Hubs, see Table 3). [ 145 ] However, these techniques tend to be very expensive and the machines, which are bulky, need to be installed in a large room (Table 3).…”

Current and future trends in periodontal tissue engineering and bone regeneration

“…Human study: posterior mandibular defects A straightforward and reproducible workflow for fabrication of highly porous (84% porosity) custom 3D-printed scaffolds for large volume alveolar bone regeneration was reported Bartnikowski et al [120] PCL: polycaprolactone; PDL: periodontal ligament; DPSCs: dental pulp stem cells The experimental group showed significantly less epithelial downgrowth and enhanced cementum + PDL regeneration compared to the control Wang et al [122] GelMa + PDLSC 3D Bioprinting in vitro 3D bioprinting conditions for attaining high resolution, dimensional stability and cell viability of periodontal ligament cells were optimized Thattaruparambil Raveendran et al [125] Polyisocyanopeptide + PLGA Electrospraying Rat: ectopic model (subcutaneous implantation)…”