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Biomedical subjects

G Majni

Publications and source records attributed to G Majni.

7 recordsLinked to original sources

Study of the interface reactions between cells and a biocompatible ceramic.

Preliminary results on the modifications induced by the growth of a Chinese Hamster Ovary (CHO) cell line on the surface of a CORD 1014 ceramic cordierite are reported. Results proved that cells strongly modify the crystallography and the chemical composition of the surface and near surface regions of the cordierite.

Animals↗

An experimental study in X-ray spectroscopy of the zirconium (Ca-PSZ) - bone interface. Microanalytic evaluation of the osteogenetic response.

Ultrastructural difractometric and chemical evaluations of calcium partially stabilized zirconium (Ca-PSZ) implants were performed in an in vivo study on animals in order to evaluate its biological behaviour. The chemical-morphological investigations demonstrated the presence of an osteogenetic activity at the bone-biomaterial interface. The new-osteogenesis was preceded by the formation of a loose connective tissue around the implants. This mesenchymal-type tissue without a capsular organization, allowing modulation of the mechanical forces to which the implant is subject, could be considered a positive event in the osteogenetic process and not a sign of future failure of the implant. Finally, microanalytical investigations carried out on non-implanted and implanted Ca-PSZ tools suggested that the surface of this ceramic material does not undergo modification once it has been inserted in the biological environment (12 months).

Journal Article↗

[In vitro enamel fluoridation using an ultraviolet laser].

28 samples of human enamel have been studied in order to measure fluoride absorption after treatment with ultraviolet radiations. Samples treated with topical application only presented limited fluoride absorption in enamel surface (up to 0.5 microns deep). The absorption rate was higher, using an U.V. lamp. In samples treated with "excimer" laser, fluoride absorption was much higher in the surface layer and occurred also deeper (3 microns).

Absorption↗

Properties of a new carbon film for biomedical applications.

The physical and chemical properties of carbon films, about 0.5 mu thick, deposited at low temperature (40-200 degrees C) by a new physical vapour deposition technique are presented, in comparison with those of pyrolytic carbon normally used in biomedical devices. Several analytical techniques have revealed that the thin carbon films present structural properties similar to those of pyrolytic carbon. For example, similar chemical bondings of C atoms are observed in both samples. Moreover the data suggest the presence in thin C films of both tetrahedral and graphitic bondings, as in the turbostratic structure typical of pyrolytic carbon. These results confirm the similar biocompatibility properties of both types of materials already established by in vivo experiments.

Carbon↗