Effect of hydroxyapatite and titania nanostructures on early in vivo bone response.
OBJECTIVE
Hydroxyapatite (HA) or titania nanostructures were applied on smooth titanium implant cylinders. The aim was to investigate whether nano-HA may result in enhanced osseointegration compared to nano-titania structures.


METHODS
Surface topography evaluation included detailed characterization of nano-size structures present at the implant surface combined with surface roughness parameters at the micro- and nanometer level of resolution. Microstructures were removed from the surface to ensure that bone response observed was dependent only on the nanotopography and/or chemistry of the surface. Early in vivo histological analyses of the bone response (4 weeks) were investigated in a rabbit model.


RESULTS
In the present study, nano-titania-coated implants showed an increased coverage area and feature density, forming a homogenous layer compared to nano-HA implants. Bone contact values of the nano-titania implants showed a tendency to have a higher percentage as compared to the nano-HA implants (p = .1).


CONCLUSIONS
Thus, no evidence of enhanced bone formation to nano-HA-modified implants was observed compared to nano-titania-modified implants. The presence of specific nanostructures dependent on the surface modification exhibiting different size and distribution did modulate in vivo bone response.
Meirelles
Luiz
L
Department of Prosthetic Dentistry, Institute of Odontology, Sahlgrenska Academy at Göteborg University, Göteborg, Sweden. meirelles@odontologi.gu.se
Melin
Lory
L
Peltola
Timo
T
Kjellin
Per
P
Kangasniemi
Ilkka
I
Currie
Fredrik
F
Andersson
Martin
M
Albrektsson
Tomas
T
Wennerberg
Ann
A
D000818:Animals; D020099:Coated Materials, Biocompatible; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D017886:Durapatite; D020007:Implants, Experimental; D007368:Interferometry; D008297:Male; D018625:Microscopy, Atomic Force; D049329:Nanostructures; D016348:Osseointegration; D011817:Rabbits; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013977:Tibia / Q000601:surgery; D014025:Titanium
D020099:Coated Materials, Biocompatible; D015921:Dental Implants; C009495:titanium dioxide; D017886:Durapatite; D014025:Titanium