Influences of Compressive Force and Zoledronic Acid on Osteoblast Proliferation and Differentiation: An In Vitro Study

This study investigates the effects of zoledronic acid (ZA) and compressive force on osteoblast functions, to elucidate the pathogenesis of medication-related osteonecrosis of the jaw (MRONJ). MC3T3-E1 cells were exposed to ZA (1, 10 and 100 µM) to evaluate the effects of ZA on cell proliferation. Furthermore, to investigate the influence of ZA with or without compressive force on osteoblast differentiation, real-time polymerase chain reaction and Alizarin Red S staining were performed. ZA concentrations > 10 μM were highly cytotoxic to MC3T3-E1 cells. Combining 1-μM ZA with compressive force influenced expression levels of osteoblast-related genes and matrix mineralization. The inhibitory effects of ZA on cell proliferation and the combination of ZA and compressive force on osteoblast differentiation may contribute to the pathogenesis of MRONJ.