A comparative evaluation of the systemic and local alendronate treatment in synthetic bone graft: a histologic and histomorphometric study in a rat calvarial defect model

Abstract

The purpose of this study was to compare the relative efficacy of systemic and local alendronate treatment of synthetic bone graft in a rat calvarial defect model. Forty Wistar rats were divided into 4 groups: experimental animals received alendronate systemically or locally combined with micro-macroporous biphasic calcium phosphate (MBCP) graft material. In the control group, the defect was left empty. On each animal, a 5-mm standardized bone defect was created with a standard trephine bur in calvarium. All animals were killed after 8 weeks. The number of osteoclasts, osteoclast morphology, resorption lacunae, osteoblastic activity, and lamellar bone formation were histopathologically evaluated and the newly formed bone area was analyzed histomorphometrically. Eight weeks after surgery, the number of osteoclasts and the resorption lacunae in the MBCP group using systemic alendronate therapy was significantly higher than those of the other groups (P < .05). Osteoblast number in the MBCP group using systemic alendronate treatment was significantly increased (P < .05). No significant difference was found among all MBCP groups using local or systemic alendronate treatments with regard to new bone formation (P > .05). Within the limits of the study, alendronate, when administered systemically or locally, did not increase bone regeneration with MBCP graft in the rat calvarial defect model.