Effect of hydroxyapatite-coating on the bonding of bone to titanium implants in the femur of ovariectomized rats

Twelve rats were ovariectomized, and 12 rats were control. After 24 weeks, all rats had HA-coated titanium cylindrical implants inserted into the medullary canal of the right femurs and uncoated implants inserted into the left femurs. Four weeks later, the implants were harvested and subjected to mechanical push-out test. The dissected left tibias were subjected to dual energy X-ray absorptiometry (DEXA). DEXA showed a 13.4% reduction in bone density in the ovariectomized group as compared with control. The push-out strength of HA-coated implants was higher than uncoated implants in both groups. No significant difference in the push-out strength of uncoated implants was measured between the control and ovariectomized group. HA-coated implants showed a 40.3% reduction in push-out strength in the ovariectomized group compared with control.