Changes in bone strength after augmentation with hydroxylapatite or hydroxylapatite/bone.

Adult, male New Zealand white rabbits had one humerus augmented with hydroxylapatite (HA) and one femur augmented with hydroxylapatite and autogenous, cortico-cancellous bone (HA-B). Contralateral bones were not augmented and used for controls. After periods of six and 16 weeks the animals were killed and the load sustained by the test and control bones at fracture was determined using three point loading. A significant increase in the load at fracture was noted in the bones augmented with either HA or HA-B.