The response of bone to nanocrystalline hydroxyapatite-coated Ti13Nb11Zr alloy in an animal model.
An in vivo study was carried out on uncoated and hydroxyapatite (HA)-coated nanostructured Ti13Nb11Zr alloy in comparison with high-grade Ti6Al4V, to investigate the effect of the different surfaces on osteointegration rate. A highly effective method to obtain a fast biomimetic deposition of a thin layer of nanocrystalline HA was applied to coat both substrates. Cylindrical pins were implanted in rabbit cortical bone and evaluated at 4 and 12 weeks by histomorphometry and microhardness tests. The results confirmed the ability of the slightly supersaturated Ca/P solution to induce a fast deposition of nanocrystalline HA on Ti alloys' surfaces. HA-coated Ti13Nb11Zr had the highest osteointegration rate at 4 and 12 weeks. Both HA-coated surfaces showed an affinity index significantly higher than those of native surfaces at 4 weeks (Ti13Nb11Zr+HA: 37%; Ti6Al4V+HA: 26%). Microhardness test showed a significantly higher bone mineralization index of HA-coated Ti13Nb11Zr in comparison with that of HA-coated Ti6Al4V surface. The study suggests that the HA coating on both alloys enhances bone response around implants and that there is a synergic effect of Ti-Nb-Zr alloy with the HA coating on bone remodeling and maturation.
Bigi
Adriana
A
Department of Chemistry G. Ciamician, University of Bologna, Via Selmi 2, 40126 Bologna, Italy.
Fini
Milena
M
Bracci
Barbara
B
Boanini
Elisa
E
Torricelli
Paola
P
Giavaresi
Gianluca
G
Aldini
Nicolò N
NN
Facchini
Alessandro
A
Sbaiz
Fausto
F
Giardino
Roberto
R
D000497:Alloys / Q000737:chemistry* / Q000494:pharmacology*; D000818:Animals; D001842:Bone and Bones / Q000187:drug effects*; D017886:Durapatite / Q000737:chemistry* / Q000494:pharmacology*; D008855:Microscopy, Electron, Scanning; D023421:Models, Animal; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011817:Rabbits; D014961:X-Ray Diffraction
D000497:Alloys; C528281:Ti13Nb11Zr alloy; D017886:Durapatite