Abstract
The repair of bone defects remains a major clinical challenge, as autologous grafts are constrained by donor limitations and bioinert implants often necessitate secondary surgeries. Absorbable materials, including polymers, ceramics, and metals, are rapidly transforming orthopedic care by offering temporary support and synchronized degradation to match tissue regeneration. This review highlights cutting-edge advances in composite scaffolds that enhance mechanical integrity, degradation kinetics, and osteoinductivity. We further explore innovative systems integrating stimuli-responsive smart materials (e.g., photothermal, piezoelectric), 4D printing smart materials, regenerative therapies, and bone organoids. Emerging clinical data are discussed in the context of diseases such as osteonecrosis, osteomyelitis, and osteoporosis. Looking forward, we outline transformative directions, including AI-driven scaffold design, gradient architectures, and immunomodulatory strategies to resolve the spatiotemporal mismatch between degradation and regeneration. This review offers a forward-looking framework for next-generation multifunctional, bioresponsive orthopedic implants.