Osteoinductive and Piezoelectrically Malleable Nanocomposite Bone Graft

Repairing jawbone defects remains a clinical challenge due to the limited adaptability and regenerative capacity of conventional grafts. In this study, we designed an osteoinductive and piezoelectric composite for jawbone repair which possessed a plasticine-like texture, termed as "osteoplasticine." This material combines a stereocomplex of poly(l/d)-lactic acid and a poly(ε-caprolactone) network, imparting thermoplasticity and enabling uniform dispersion of two functional ceramic nanoparticles. Nanosized hydroxyapatite particles provide bone-forming capability, while the nanopotassium sodium niobate particles promote osteogenic differentiation and metabolic activity through piezoelectric cues upon mechanical loading or ultrasound stimulation. The osteoplasticine we synthesized exhibits good moldability when heated above physiological temperature and elicits measurable electrical signals when used. Leopard-spotted pattern osteogenesis was observed in the osteoplasticine group at both osseous and nonosseous implantation sites. Abundant bone regenerating nodules (∼55 μm) were found in the central region of the material. The local renin-angiotensin-aldosterone system is involved in this process. This work presents a moldable and piezoelectrically responsive bone graft material that shows potential for future integration with noninvasive stimulation strategies to repair complex maxillofacial bone defects.