Lower Elastic Modulus of Novel Zr58Cu25Al14Nb3 Dental Implants Improves Stress Distribution and Osteogenesis in Peri-implant Alveolar Bone Under Physiological Loading

While implant materials with bone-mimetic elastic moduli are theoretically advantageous for reducing the stress shielding effect, the underlying mechanism remains incompletely understood, particularly in alveolar bone applications. In this study, we investigate the mechanism of excellent peri-implant bone quality of a Zr58Cu25Al14Nb3 bulk metallic glass (Nb3) dental implant in terms of its lower elastic modulus than commercial pure titanium (cpTi) and the stress distribution under masticatory mechanical loading. In vitro, Nb3 exhibits enhanced osteogenic potential over cpTi. In vivo, rat maxillary molar implants are subjected to a controllable cyclic loading program (10 N, 3 Hz, 0.12 s duration, 1800 cycles/day). The animal model coupled finite element analysis confirms that the lower elastic modulus of Nb3 implants promotes the more physiological stress distribution, and thus reduces stress concentration while increasing strain energy density in peri-implant bone. Histomorphometry reveals that loaded Nb3 implants significantly accelerate mineral apposition rate, upregulate collagen III, and increase osteoblast density while reducing osteocyte number, demonstrating improved mechano-adaptation. Transcriptomics identify coordinated upregulation of osteogenic, angiogenic, and mechanosensitive markers in Nb3-loaded bone. Immunohistochemistry validates elevated expression of osteopontin and periostin, key mediators of mechanical signaling. These findings establish that Nb3's optimal elastic modulus enhances peri-implant bone quality through biomechanical optimization of stress transfer that further activates mechanotransductive osteogenesis, providing a material-based solution to stress shielding. Overall design: To investigate the genetic changes of peri-implant bone with or without cyclic loading. Mini implants of titanium and novel material Nb3 were inserted at rat's maxillary first molar site. Implants of the loading group were subjected to cyclic loading for 2 weeks, while implants of the non-loading group remained static. F4mm of peri-implant bone tissues were collected for RNA sequencing.