3D printed flexible composite scaffold with ultrasonic-driven wireless electrical stimulation promotes neuro-vascularization for critical-size bone defects regeneration

, when subjected to noninvasive low-intensity pulsed ultrasound as a stimulus, the scaffolds exhibited controllable wireless electrical stimulation properties with tunable duration and intensity to meet specific therapeutic requirements. In vitro experiments illustrating electrical stimulation can significantly promote neuralization, vascularization and osteogenic differentiation. Furthermore, the 3D printed flexible composite scaffolds with ultrasonic-driven wireless electrical stimulation facilitated neuro-vascularization network reconstruction and osteogenic proteins up-regulation in rat calvarial critical-sized defect models of 7 mm, thereby accelerating the regeneration and repair of critical-size bone defects. It held great potential as a promising material for critical-size bone defects treatment.