Bioactivity of bioglasses composed by niobium: an in vivo experimental study

Abstract

The biomaterials are used in many areas of medicine and ondontology and to the 70 they were characterized by being bioinert. In 1970 the researcher L. L Hench developed the first bioactive glass, the Bioglass® 45S5. This glass is a kind of biomaterial made from the SiO2 - CaO - Na2O complex that has the capability to form binds between live tissue and glass, beyond being bioinert. The Bioglass® discovery encouraged many others researchers to seek another materials that also show the same properties of Hench`s bioglasses, however, none biomaterial produced by them showed mechanic performance enough to be used under constant load. Some recent studies showed that putting niobium oxide into metallic alloys would be a solution to improve its mechanic resistance, keeping the same biocampability but there are few studies that incorporated the niobium oxide in bioactive glasses, in this context, the aim of this study is to evaluate the bioactive properties of bioglasses enriched with different concentrations of Nb2O5 in rats. For this the material, in the powder form, and containing different concentrations of Nb2O5 for each group, will be implanted in rats as well as the Bioglass 45S5 (Bioglass®) will be implanted in a group to be the control group. Moreover, bioglasses rods containing the same niobium oxide concentrations of those powders preparations will be implanted at the proximal third of the tibia to assay the material osseointegration. The sacrifices will happen after two and four weeks postoperative to evaluate the implant effects. Histological slides will be stained with hematoxyin and eosin for qualitative and quantitative measurement (morphometry) of osteoconduction, osteoinduction and biocompatibility. Also immunohistochemical staining technical will be used to assess the material's capability to stimulate angiogenesis. (AU)