Effect of Zoledronic Acid Application on Different Graft Materials in Calvarial Bone Defect Models. An Experimental...

To determine the effect of zoledronic acid on graft materials in bone calvarial defects.

Eighty adult (12 weeks) Sprague-Dawley male rats weighing from 300-350 g were divided into groups: calvarial defect, calvarial defect + synthetic graft, and calvarial defect + xenograft. All groups received zoledronate intravenously for a week after surgery and were sacrificed at either 6 or 12 weeks after their operation. The rat calvariae were fixed in 10% neutral buffered formalin before decalcification in 10% ethylenediaminetetraacetic acid for 20 days. Calvarial bone samples were then dehydrated and processed for embedding in paraffin wax. Sections 5 μm thick were stained with hematoxylin and eosin and examined by light microscopy.

The effects of zoledronic acid, a third-generation nitrogen-containing bisphosphonate, on different graft materials in rats with critical-size calvarial defects were analyzed and compared. Significantly less graft resorption was identified in zoledronic acid-treated rats that had received a xenograft than in either the untreated rats or those with a synthetic graft. In the xenograft group primary ossification was visible at week 12, and the graft had entered the bone to a greater extent than in the other experimental groups or in the control group. Osseous structures were also observed more clearly in this group than in the others.

Zoledronic acid histopathologic bone graft stimulates bone formation. Zoledronic acid may be considered among the therapeutic methods available to improve the bone formation process in calvarial bone formation.