3D‐Printed Osteoinductive Polymeric Scaffolds with Optimized Architecture to Repair a Sheep Metatarsal Critical‐Size Bone Defect

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, μCT 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 μm and a low BMP‐2 dose of ∼120 μg/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.This article is protected by copyright. All rights reserved