Multi-scale cellular PLA-based bionic scaffold to promote bone regrowth and repair

Large bone defects have presented a significant challenge in orthopedic treatments, and the emergence of tissueengineered scaffolds has introduced new avenues for treatment. Nonetheless, the clinical application of such scaffolds has been hindered by drawbacks like inadequate mechanical properties, and deficient osteogenesis. Herein, a biocompatible polylactic acid (PLA) based composite was proposed to emulate cancellous bone's morphology by incorporating nano-hydroxyapatite (nHA). In addition, a quantity of Mg2+ and chitosan (CS) as active osteogenic factors were adopted to imitate the bone marrow mesenchymal components in vivo. Using a pre-evaporated solvent and sacrificial multi-template techniques, the cellular PLA-based tissue engineering scaffolds containing macropores larger than 100 & mu;m and micropores smaller than 10 & mu;m were developed. The scaffold's bionic structure, osteogenic active component, and multi-scale cellular make it comparable to cancellous bone, with favorable mechanical properties and hydrophilicity. Vitro tests using Sprague-Dawley (SD) rat bone marrow mesenchymal stem cells (rBMSCs) demonstrated the scaffold's excellent biocompatibility to induce high efficiency of osteogenic differentiation. The bionic porous scaffold with multi-scale cellular structure also can recruit rBMSCs, promote bone regrowth and osteogenic differentiation, and facilitate the regeneration of defective bone tissue for repair. This contribution presented a promising strategy for future advancements in bone tissue engineering.

Automated summary

Large bone defects pose a challenge in orthopedic treatments, but tissue-engineered scaffolds provide new possibilities. However, the clinical use of such scaffolds has been limited by inadequate mechanical properties and osteogenesis. This study proposes a biocompatible PLA-based composite with nano-hydroxyapatite to mimic cancellous bone's morphology, along with Mg2+ and chitosan as active osteogenic factors. The resulting scaffold has a bionic structure, favorable mechanical properties, and induces efficient osteogenic differentiation, making it a promising strategy for bone tissue engineering.