Self-reinforced piezoelectric chip for scaffold-free repair of critical-sized bone defects
Wei Li, Youtian Mo, Xie Shaohua, Lei Fu, Yan Ye, Yilin Zhou, Jianming Lai, Wenliang Wang, Yao Lu, Guoqiang Li, Jing Tian
Abstract
The use of piezoelectric materials to treat critical-sized bone defects typically requires additional stimulation to generate their piezoelectric properties and the implantation of scaffolds to promote bone repair. Here we present a self-reinforced piezoelectric chip and demonstrate its efficacy in the treatment of critical-sized bone defects. Specifically, the chip is comprised of the third-generation semiconductor aluminum nitride (AlN) as a piezoelectric layer, molybdenum (Mo) electrodes, and a silicon substrate with an optimized internal cavity structure. All these components are confirmed to be non-cytotoxic. This design enables the chip to provide self-sustained and long-term electrical signals in response to physiological vibrations. After being implanted into a rabbit critical-sized femoral defect model, the chip creates a localized bioelectric microenvironment, thereby promoting vascularized bone repair within 4 weeks without using any scaffolds and additional tools. Moreover, the chip can be fixed onto the clinically used orthopedic plate system, representing a universal plug-and-play strategy. Piezoelectric materials for bone repair usually require scaffold filling and external stimulation. Here, the authors present a self-reinforced chip that can spontaneously generate piezoelectric effect under physiological vibrations to achieve scaffold-free repair of critical-sized bone defects