Harnessing piezoelectricity for bone tissue engineering: recapitulating the electrophysiological microenvironment through smart biomaterials.

Natural bone tissue is a highly dynamic electrophysiological microenvironment, where endogenous piezoelectricity plays a pivotal role in regulating bone remodeling and homeostasis. Addressing the complex clinical challenges of bone defects, piezoelectric biomaterials have emerged as a revolutionary self-powered therapeutic strategy, reconstructing this critical biophysical niche through electromechanical conversion. This article systematically reviews the classification and characteristics of inorganic ceramics, organic polymers, composites, and emerging systems. Advanced energy conversion strategies, ranging from physiological motion to low-intensity pulsed ultrasound actuation, are critically evaluated. Furthermore, the multi-scale mechanisms involving ion channel activation, cellular energy metabolism reprogramming, osteoimmune microenvironment remodeling, and osteogenic gene transcription and mineralization are elaborated. Ultimately, this review aims to provide profound theoretical guidance for the clinical translation of next-generation smart orthopedic implants.