Fabrication and properties of PLA/nano-HA composite scaffolds with balanced mechanical properties and biological functions for bone tissue engineering application

Wenzhao Wang,Li Wang,Boqing Zhang,Jun Li,Mingxin Li,Lihong Zhao,Zhengdong Zhang,Lei Liu,Yanlong Han,Changchun Zhou

doi:10.1515/ntrev-2021-0083

Abstract

Abstract Repair of critical bone defects is a challenge in the orthopedic clinic. 3D printing is an advanced personalized manufacturing technology that can accurately shape internal structures and external contours. In this study, the composite scaffolds of polylactic acid (PLA) and nano-hydroxyapatite (n-HA) were manufactured by the fused deposition modeling (FDM) technique. Equal mass PLA and n-HA were uniformly mixed to simulate the organic and inorganic phases of natural bone. The suitability of the composite scaffolds was evaluated by material characterization, mechanical property, and in vitro biocompatibility, and the osteogenesis induction in vitro was further tested. Finally, the printed scaffold was implanted into the rabbit femoral defect model to evaluate the osteogenic ability in vivo. The results showed that the composite scaffold had sufficient mechanical strength, appropriate pore size, and biocompatibility. Most importantly, the osteogenic induction performance of the composite scaffold was significantly better than that of the pure PLA scaffold. In conclusion, the PLA/n-HA scaffold is a promising composite biomaterial for bone defect repair and has excellent clinical transformation potential.

Highlights

Critical bone defects cannot heal themselves, and the current autogenous bone grafting is not ideal for repairing critical defects [1]
Femur samples were taken at 1 month, 2 months, and 3 months after surgery and fixed in 4% paraformaldehyde solution. 3D data were collected by micro-computerized tomography (CT) (Quantum GX, USA)
The implant provides a suitable environment for cell adhesion and growth and has the ability of bone conduction and osteoinduction to guide bone regeneration and growth [8,33]

Summary

Introduction

Critical bone defects cannot heal themselves, and the current autogenous bone grafting is not ideal for repairing critical defects [1]. Revision surgeries are usually required to repair bone defects clinically [2,3]. Researchers have been working to develop an alternative to artificial bone grafts, known as synthetic bone graft substitutes [1]. The primary artificial scaffold was to fill the defect area, but with the progress of technology, the current expectation of synthetic bone defect scaffold has become active induction of bone regeneration and reconstruction of the primary bone [5]. The exploration of scaffolds in bone tissue engineering is divided into two aspects: one is to explore and configure the scaffolds that can support and

Methods

Results

Conclusion