The effects of etidronate (HEBP) on osseointegration of sintered porous-surfaced implants in rabbit femur

Improvement in osseointegration can be beneficial where the bone is of poor quality or where excessive functional loading is anticipated. The bisphosphonate HEBP has been shown to accelerate healing in bone wounds. Hence it was thought that osseointegration might be accelerated and/or enhanced with this drug. Experimental rabbits received HEBP injections, and control rabbits received saline. EndoporeRTM implants were placed in each femoral condyle. Outcome measurements consisted of pull-out testing and morphometric analyses. HEBP administration demonstrated an overall significant effect on bone. Experimental rabbits demonstrated less mineralized bone matrix and greater osteoid compared to controls, and the drug's peak effect was notable only 9 days post-operatively. HEBP did not have any effect in the first 3 days post-operatively. HEBP did not accelerate or enhance osseointegration during the observation time. This might suggest that HEBP dosage and timing of administration may be crucial factor insofar as acceleration of osseointegration is concerned.