[Necessity and validity of standard models for experimental preclinical evaluation of biomaterials. An example of biologic characterization of a hydroxyapatite-based implant material].
A large number of methods are now available for the preclinical screening of implantable materials concerning their biocompatibility and their ability to stimulate tissue formation. In vitro techniques represent a very useful tool, since this way we can realistically simulate the biological events which occur in vivo at the bone-implant interface. In the present study scanning electron microscopy and light microscopy observations were performed in order to assess the effect of an hydroxyapatite granulate on cell behaviour and morphology. Uptake of proteins to hydroxyapatite surface has been also investigated by comparing the amounts adsorbed after incubation with bovine serum albumin and bovine pancreaticamilase. According to our preliminary observation cells do not show signs of toxicity or inhibition of cell growth even after 14 days of co-culture with hydroxyapatite. Granules were covered by an uninterrupted cell layer by day seven. Even after two days micrographs show cells anchored and spread over the surface of the underlying granules, with a flattened and stellate shape. Such a morphology indicates a very high cellular activity, suggesting that the interaction with hydroxyapatite seriously increased metabolism. Measurements of protein adsorption on the hydroxyapatite surface show that changes in the size of particles affect the binding of proteins, while, in the case of granular hydroxyapatite, despite changes in size of granules, variations of protein adsorption were not observed, neither in relation to their different isoelectric point. Our preliminary results represent a good example of the opportunities presented by an experimental in vitro model.
Caropreso
S
S
Cattedra di Materiali Dentari, Università degli Studi di Roma, Tor Vergata.
Cerroni
L
L
Marini
S
S
Cocchia
D
D
Martinetti
R
R
Condò
S G
SG
D001672:Biocompatible Materials; D003757:Dental Implantation; D017886:Durapatite; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D008954:Models, Biological
D001672:Biocompatible Materials; D017886:Durapatite