3D-printed polymeric scaffolds with optimized architecture to repair a sheep metatarsal critical-size bone defect

GAROT, C.; Schoffit, S.; Monfoulet, C.; Machillot, P.; DEROY, C.; ROQUES, S.; VIAL, J.; Vollaire, J.; Renard, M.; GHANEM, H.; El-Hafci, H.; DECAMBRON, A.; Josserand, V.; BORDENAVE, L.; BETTEGA, G.; DURAND, M.; MANASSERO, M.; VIATEAU, V.; LOGEART-AVRAMOGLOU, D.; PICART, C.

doi:10.1101/2022.12.14.520447

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bioRxiv · 10.1101/2022.12.14.520447

3D-printed polymeric scaffolds with optimized architecture to repair a sheep metatarsal critical-size bone defect

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Abstract

The reconstruction of critical-size bone defects in long bones remains a challenge for clinicians. We developed a new bioactive medical device for long bone repair by combining a 3D-printed architectured cylindrical scaffold made of clinical-grade polylactic acid (PLA) with a polyelectrolyte film coating delivering the osteogenic bone morphogenetic protein 2 (BMP-2). This film-coated scaffold was used to repair a sheep metatarsal 25-mm long critical-size bone defect. In vitro and in vivo biocompatibility of the film-coated PLA material were proved according to ISO standards. Scaffold geometry was found to influence BMP-2 incorporation. Bone regeneration was followed using X-ray scans, {micro}CT scans, and histology. We showed that scaffold internal geometry, notably pore shape, influenced bone regeneration, which was homogenous longitudinally. Scaffolds with cubic pores of [~]870 {micro}m and a low BMP-2 dose of [~]120 {micro}g/cm3 induced the best bone regeneration without any adverse effects. The visual score given by clinicians during animal follow-up was found to be an easy way to predict bone regeneration. This work opens perspectives for a clinical application in personalized bone regeneration.

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GAROT, C., Schoffit, S., Monfoulet, C., Machillot, P., DEROY, C., ROQUES, S., VIAL, J., Vollaire, J., Renard, M., GHANEM, H., El-Hafci, H., DECAMBRON, A., Josserand, V., BORDENAVE, L., BETTEGA, G., DURAND, M., MANASSERO, M., VIATEAU, V., LOGEART-AVRAMOGLOU, D., PICART, C.. 2022-12-16. 3D-printed polymeric scaffolds with optimized architecture to repair a sheep metatarsal critical-size bone defect. https://doi.org/10.1101/2022.12.14.520447

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