ABSTRACT
PURPOSE: The purpose of this study was to compare the mitigative effect of alendronate and risedronate on osteolysis in the mouse calvarian model by using titanium (Ti) and polymethylmethacrylate (PMMA) particles. MATERIALS AND METHODS: Experimental mice (male C57/BL6) are divided into three groups; control, Ti particle-treated and PMMA particle-treated group. Each Ti and PMMA particle-treated group was divided into three subgroups which received no bisphosphonates, which received alendronate, and which received risedronate. We measured number of osteoclast, area of osteolysis, bone and soft tissue thickness, ratio of bone and total tissue on mid-sagittal suture area (MSSA) and compared between two groups. RESULTS: Both alendronate and risedronate had significant inhibitory effect on Ti or PMMA particle-induced osteolysis in mouse calvarian model (p<0.05). Furthermore, bisphosphonates prevented formation of particleinduced osteolysis as RANK/Fc. Risedronate had better capability for preserving bone thickness in PMMA treated mice and also showed decreased soft tissue thickness in Ti treated mice than alendronate (p<0.05). CONCLUSION: Both alendronate and risedronate may be an effective agents on mitigation of Ti and PMMA particle-induced osteolysis. However, risedronate showed better structual bone preserving capacity than alendronate in particle-treated mouse calvariae.