Photothermally Triggered Smart Bandages for Temperature‐Controlled Fixation and Bone Regeneration

Abstract The repair of traumatic bone defects presents high demands for advanced biomaterials that can simultaneously provide anatomical conformability, dynamic mechanical stimulation, and stable fixation. Herein, a smart bandage system comprising a bilayer actuating substrate and a photothermally responsive 3D‐printed hydrogel scaffold is engineered. The bilayer substrate enables temperature‐dependent, reversible shape transformations, allowing adaptive and conformal fixation under physiological conditions, while the top scaffold effectively converts near‐infrared (NIR) light into heat, triggering programmable shape morphing and promoting bone repair. In vitro studies demonstrated that the system enhances osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) by modulating the Wnt/Hippo signaling pathways. In vivo results confirmed that the smart bandage significantly enhanced bone regeneration, inducing a 3.9‐fold more new bone formation compared to the control group. By closely mimicking the dynamic mechanical microenvironment of natural bone healing, this smart bandage offers an integrated strategy combining mechanical stimulation and secure fixation, highlighting its potential for advanced bone regenerative therapies.