Objective To investigate the influence of systemic application of Alendronate sodium, a bone resorption inhibitor, on the osseointegration of implant-bone interface in estrogen-deficient rabbits through mechanical assessment. Methods 27 five-month-old Japanese white female rabbits were randomly divided into three groups（9 rabbits each group）. An ovariectomy group（OVX）, an ovariectomy and Alendronate sodium group（ALN） and a shamed- operated group（S）. 12 weeks after operation, implants were installed into bilateral distal femurs and proximal tibias in each group. Alendronate sodium was administrated by intraperitoneal injection in ALN group; meanwhile equivalent of normal saline was administrated by intraperitoneal injection in OVX group and S group. Bone mineral density was measured right after the implant operation and also in 4, 8, 12 weeks. Torque-out values were measured in 4, 8, 12 weeks after animal sacrifice. Results Bone mineral density of tibias in ALN group was closed to S groupand was significantly different from OVX group（P
