Covalently-linked hyaluronan promotes bone formation around Ti implants in a rabbit model.
The goal of this study was the in vivo evaluation of nanoporous titanium (Ti) implants bearing a covalently linked surface hyaluronan (HA) layer. Implant surface topography and surface chemistry were previously evaluated by scanning electron microscopy and X-ray photoelectron spectroscopy. Results showed that the surface modification process did not affect surface topography, yielding a homogeneously HA-coated nanotextured implant surface. In vivo evaluation of implants in both cortical and trabecular bone of rabbit femurs showed a significant improvement of both bone-to-implant contact and bone ingrowth at HA-bearing implant interfaces at 4 weeks. The improvement in osteointegration rate was particularly evident in the marrow-rich trabecular bone (bone-to-implant contact: control 22.5%; HA-coated 69.0%, p < 0.01). Mechanical testing (push-out test) and evaluation of interfacial bone microhardness confirmed a faster bone maturation around HA-coated implants (Bone Maturation Index: control 79.1%; HA-coated 90.6%, p < 0.05). Suggestions based on the biochemical role of HA are presented to account for the observed behavior.
Morra
Marco
M
Nobil Bio Ricerche, Str. S. Rocco 36, 14018 Villafranca d'Asti, Italy. mmorra@nobilbio.it
Cassinelli
Clara
C
Cascardo
Giovanna
G
Fini
Milena
M
Giavaresi
Gianluca
G
Giardino
Roberto
R
D000818:Animals; D020099:Coated Materials, Biocompatible; D005269:Femur / Q000601:surgery; D006820:Hyaluronic Acid / Q000494:pharmacology*; D020007:Implants, Experimental; D008297:Male; D008855:Microscopy, Electron, Scanning; D016348:Osseointegration / Q000187:drug effects*; D010012:Osteogenesis; D011817:Rabbits; D013057:Spectrum Analysis; D013499:Surface Properties; D014025:Titanium; D014965:X-Rays
D020099:Coated Materials, Biocompatible; D006820:Hyaluronic Acid; D014025:Titanium