Abstract
Current research efforts aim at enhancing osseointegration of cementless implants to improve early bone fixation.
The aim of the present study was to investigate whether bone morphogenic protein (BMP) 2 had a positive effect on the osseointegration of hydroxyapatite coated implants.
Hydroxyapatite (HA) implants were coated with BMP-2 and hyaluronic acid (HY) as the carrier or with HY alone. Uncoated HA-implants served as controls. The osseointegration of the implants was evaluated either by light microscopy and pullout tests after 1, 2 and 4 weeks of unloaded implantation in the cancellous bone of 18 sheep.
The BMP-2 coating significantly increased bone growth into the perforations of HA-implants. The proportion of bone-ingrowth at 4 weeks was 32% for the BMP-implants compared to 12% for HA implants. However, BMP-2 did not enhance the percentage of bone implant contact and interface shear strength values.
Conclusion: This study indicates that BMP-2 may help to increase bone growth across gaps of cementless implants in the early stages of bone healing improving fixation and decreasing the risk of loosening.
The abstracts were prepared by Jean-Claude Theis. Correspondence should be addressed to him at Department of Orthopaedic Surgery, Dunedin Hospital, Private Bag 1921, Dunedin, New Zealand.
