Improved osseointegration of PTFEP-coated titanium implants

Background: Clinical success of bone implants is critically related to the interaction between the implant surface and the surrounding tissue. The polymer poly (bis (triflnorocthoxy) phosphazene) (PTFEP) is a promising, highly biocompatible surface coating which also inhibits the adsorption of granulocytes, macrophages, inflammatory cells, bacteria, and platelets. However, there is limited clinical experience of PTFEP as a coating for bone implants. Therefore PTFEP-coated titanium implants in an animal model were examined. Material/Methods: PTFEP-coated titanium cylinders were implanted into the lateral femoral condyles of rabbits. Osseointegration was examined six weeks and six months after implantation using a non-destructive mechanical pull-out measurement and a histological analysis. Results: The results indicate improved osseointegration of PTFEP-coated implants. Six weeks after implantation, the PTFEP-coated implants showed a higher stiffness (pull-out length [pol]=7.1 +/- 2.0 Inn) compared with uncoated cylinders (pol=10.2 +/- 3.4 Inn, p < 0.05). Six months after implantation, the mechanical properties of both implants had adjusled, and histological analysis revealed an increased bone-implant interface of PTFEP-coated cylinders compared with the first 6 weeks (17.5% vs. 8.2% in controls, p < 0.05). Conclusions: Taken together, the results of this preliminary study indicate promising applications of PTFEP as a coating material for bone implants.