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(trifluoroethoxy)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.


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 microm) compared with uncoated cylinders (pol=10.2+/-3.4 microm, p<0.05). Six months after implantation, the mechanical properties of both implants had adjusted, 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.
Zeifang
Felix
F
Department of Orthopedic Surgery, University of Heidelberg, Germany.
Grunze
Michael
M
Delling
Gunter
G
Lorenz
Helga
H
Heisel
Christian
C
Tosounidis
Georgios
G
Sabo
Desiderius
D
Simank
Hans-Georg
HG
Holstein
Joerg H
JH
D000818:Animals; D001696:Biomechanical Phenomena; D020099:Coated Materials, Biocompatible; D005260:Female; D005269:Femur / Q000033:anatomy & histology / Q000502:physiology / Q000601:surgery; D008422:Materials Testing; D009943:Organophosphorus Compounds; D016348:Osseointegration / Q000502:physiology; D011108:Polymers; D019736:Prostheses and Implants; D011817:Rabbits; D013997:Time Factors; D014025:Titanium
D020099:Coated Materials, Biocompatible; D009943:Organophosphorus Compounds; D011108:Polymers; C081660:poly(bis(trifluoroethoxy)phosphazene); D014025:Titanium