Research progress on the application of piezoelectric hydrogel materials in bone tissue engineering.

Piezoelectric hydrogels have emerged as a class of biomaterials that have garnered significant attention in bone tissue engineering in recent years. Their unique property lies in their ability to generate electrical charges under mechanical deformation. This piezoelectric effect is key to enhancing bone regeneration by mimicking the natural mechanical forces that stimulate osteogenesisin vivo. With their high water content, elasticity, biocompatibility, and capacity to modulate cellular responses through electrical stimulation (ES), they present an ideal choice for bone defect repair. Recent studies have demonstrated that ES can significantly promote osteoblast differentiation and bone formation, making piezoelectric hydrogels a critical factor in facilitating bone tissue regeneration. By integrating piezoelectric materials into hydrogels, they not only support cell growth but also actively promote bone healing through mechanoelectrical signaling. Specifically, this review (i) quantifies the range of piezoelectric coefficients and electrical outputs reported for hydrogels, (ii) critically compares fabrication methods with their scalability limitations, and (iii) outlines design guidelines for achieving stable, clinically translatable piezoelectric systems. By bridging materials science and bioelectric medicine, this review provides a roadmap for developing next-generation bone repair scaffolds. Unlike previous narrative reviews, our work provides a critical comparative assessment-quantitatively comparing piezoelectric coefficients, fabrication scalability, and translational bottlenecks.