Processing‐Structure‐Property Relationships and Mechanical Limitations of PLA/PCL/HA Biocomposites for Bone Tissue Engineering: A Critical Review
TL;DR
Future research should integrate standardized mechanical testing, long‐term degradation–mechanics assessment, cyclic loading evaluation, and microstructural optimization to support the development of mechanically reliable PLA/PCL/HA scaffolds for bone repair.
Abstract
Polylactic acid (PLA), polycaprolactone (PCL), and hydroxyapatite (HA) biocomposites are widely investigated as biodegradable scaffolds for bone tissue engineering because they combine mechanical support, tunable degradation, and osteoconductive functionality. This critical review examines how material composition and fabrication routes, including solvent casting, freeze‐drying, melt processing, electrospinning, and additive manufacturing, govern pore architecture, polymer phase morphology, HA dispersion, and interfacial interactions, thereby determining mechanical performance, degradation behavior, and biological function. PLA primarily provides stiffness, PCL improves ductility and toughness, while HA enhances osteoconductivity and may reinforce the polymer matrix when uniformly dispersed. Across the reviewed studies, scaffold performance varied substantially because of differences in composition, processing conditions, porosity, and mechanical testing configurations. However, inconsistent testing protocols, incomplete mechanical data reporting, and limited evaluation of fatigue and creep behavior remain major barriers to direct comparison and clinical translation. Future research should integrate standardized mechanical testing, long‐term degradation–mechanics assessment, cyclic loading evaluation, and microstructural optimization to support the development of mechanically reliable PLA/PCL/HA scaffolds for bone repair.