Papers by Author: M.P. Ginebra

Abstract: Resorbable calcium phosphate glasses offer interesting solutions in the biomedical field, as bone cavity fillers, drug delivery systems, biodegradable reinforcing phase in the case of composites for bone fixation devices and tissue engineering scaffolds. In this work, two different glass formulations in the systems 44.5CaO-44.5P2O5-(11-X)Na2O-XTiO2 (X=0or 5) have been elaborated. It is known that the incorporation or TiO2 into the vitreous system reduces considerably the solubility of the glasses. To study the material solubility effect on the in vivo response, glass particles of the two formulations were implanted in rabbits. Results showed that both glasses elicited a similar biological response and good biocompatibility. The percentage of new bone formation in the glasses was comparable to that obtained for the autologous bone (control) after 12 weeks of implantation. The materials showed to have an osteoconductive potential. Finally, this study showed that in spite of the solubility difference of the studied glasses, there were no significant differences in the in vivo response.

Abstract: In this work an injectable and self setting calcium phosphate/albumen foam is developed. The effect of both the amount of albumen and the particle size of the starting a-tricalcium phosphate (a-TCP) powder on the injectability of the cement paste is studied. X-ray diffraction (XRD) and infrared (IR) analysis of the samples reveal that the hydrolysis of a-TCP to calcium deficient hydroxyapatite (CDHA) is not affected by the addition of albumen. A foamed structure formed by spherical pores with diameters between 100 and 500 µm is observed by SEM. This porous structure is maintained after injection of the paste, although some deformation of the pores is produced due to the extrusion process. The injectability of the cements is increased by the presence of albumen as compared with cements prepared in the same conditions but without foaming agent.

Abstract: Calcium phosphate cements (CPC) are being applied as bone regeneration materials. New methods are being developed to create macroporosity, in order enhance the angiogenesis, bone colonization and biodegradation of the material. In this study the effect of the incorporation of albumen as foaming agent in an a-tricalcium phosphate (a-TCP) cement, in terms of the surface roughness and in vitro cell response, was studied. The addition of albumen to CPC cements increased the surface roughness of the cements. Cell cultures, using MG63 osteoblasts, were performed and showed that cell attachment was not affected by the presence of albumen. However, cell proliferation was significantly increased in the albumen-containing cements.