3D printed scaffold combined to 2D osteoinductive coatings to repair a critical-size mandibular bone defect

BOUYER, M.; GAROT, C.; MACHILLOT, P.; VOLLAIRE, J.; FITZPATRICK, V.; MORAND, S.; BOUTONNAT, J.; JOSSERAND, V.; BETTEGA, G.; PICART, C.

doi:10.1101/2020.12.08.415778

bioRxiv · 10.1101/2020.12.08.415778

3D printed scaffold combined to 2D osteoinductive coatings to repair a critical-size mandibular bone defect

BOUYER, M.·GAROT, C.·MACHILLOT, P.·VOLLAIRE, J.·FITZPATRICK, V.·MORAND, S.·BOUTONNAT, J.·JOSSERAND, V.·BETTEGA, G.·PICART, C.

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Abstract

the reconstruction of large bone defects (12 cm3) remains a challenge for clinicians. We developed a new critical-size mandibular bone defect model on a mini-pig, close to human clinical issues. We analyzed the bone reconstruction obtained by a 3D printed scaffold made of clinical-grade PLA, coated with a polyelectrolyte film delivering an osteogenic bioactive molecule (BMP-2). We compared the results (CT-scan, CT, histology) to the gold standard solution, bone autograft. We demonstrated that the dose of BMP-2 delivered from the scaffold significantly influenced the amount of regenerated bone and the repair kinetics, with a clear BMP-2 dose-dependence. Bone was homogeneously formed inside the scaffold without ectopic bone formation. The bone repair was as good as for the bone autograft. The BMP-2 doses applied in our study were reduced 20 to 75-fold compared to the commercial collagen sponges used in the current clinical applications, without any adverse effects. 3D printed PLA scaffolds loaded with reduced doses of BMP-2 can be a safe and simple solution for large bone defects faced in the clinic.

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BOUYER, M., GAROT, C., MACHILLOT, P., VOLLAIRE, J., FITZPATRICK, V., MORAND, S., BOUTONNAT, J., JOSSERAND, V., BETTEGA, G., PICART, C.. 2020-12-09. 3D printed scaffold combined to 2D osteoinductive coatings to repair a critical-size mandibular bone defect. https://doi.org/10.1101/2020.12.08.415778

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