Matéria (Rio de Janeiro)
On-line version ISSN 1517-7076
LIMA, Cristina Jardelino de et al. Biocompatibility in vivo study of a new bioglass made up niobium oxide. Matéria (Rio J.) [online]. 2011, vol.16, n.1, pp. 574-582. ISSN 1517-7076. http://dx.doi.org/10.1590/S1517-70762011000100004.
The aim of this study was to evaluate the biological response to the implantation of a new biocompatible glass based on niobium oxide and phosphorus oxide. Scanning electron microscopy with energy dispersive spectroscopy evaluated the morphology of the material (SEM/EDS) and the tissue response was evaluated by implantation of 30mg of biocompatible glass on subcutaneous tissue of Balb/c mice (n=15) as ISO 10993-6. After the period of 1, 3 and 9 weeks, the animals were killed and the necropsies were fixed in buffered formalin pH 7.2 and processed for inclusion in paraffin after demineralization step in Allkymia solution; however, no demineralization conventional procedure for bone and ceramics biomaterials was sufficient to decompose the material. Alternatively, the material was processed for inclusion in resin for being cut by high impact microtome. The histopathological study considered inflammatory reaction (intensity of polymorphonuclear, mononuclear and giant multinuclear foreign body cells) and repair process (granulation tissue and fibrosis) for evaluation. SEM/EDS analysis showed irregular particles with wide size variation and presence of niobium, phosphorus, calcium and oxygen. Despite of the presence artifacts included during the histolopatological processing, microscopic analysis showed moderate inflammatory infiltrate with the presence of mononuclear cells in week 1, that disapeared in the next implantation periods. After 3 and 9 weeks, blood vessels were observed, with discrete presence of foreign body giant multinuclear cells containing particles of niobium biocompatible glass. Even after 9 weeks, no fibrous capsules were observed around the granules of material. Necrosis foci and particles degradation signs were not detected in no one experimental period. Based in these preliminary results, it was possible to conclude that the tested material is biocompatible and not bioabsorbable. The comparison of this biocompatible glass containing niobium, specially grafted into intraosseous sites, will allow the evaluation of its real potential use as bone graft.
Keywords : biomaterial; bioglass; niobium oxide; biocompatibility.