Mechanical, degradation and angiogenic characteristics of S53P4 bioactive glass

Nicole van Gestel

In current bone defect repair, autologous bone material is the golden standard to be used as graft material. The reason why autologous bone is undefeatable as graft material to date, is because of its great osteogenic, osteoinductive and osteoconductive potential, its mechanical stability and its lack of immunogenicity. However, it is known that the usage of autograft material provides several drawbacks, since harvesting the autograft warrants a second surgery site and bone quantity and quality is patient dependent. For these reasons research on materials that could replace the golden standard procedure are extensively performed on a great number of materials. S53P4 bioactive glass granules are one of the materials of interest of scientists and clinicians because of its great potential in (load-bearing) bone graft applications or as a novel treatment for bone infections (osteomyelitis). The S53P4 bioactive glass is already used in clinical practice in several clinical indications. However, to date, characteristics like degradation rates and mechanisms, angiogenic and load-bearing potential of bioactive glass granules are not well understood or even unknown. Moreover, new formulations are being developed for more specific applications or to improve user-friendliness. Research on these new bioactive glass based materials is still missing, while very important for the applications.

This research therefore focuses on the degradation, mechanical properties and angiogenic potential of the S53P4 bioactive glass granules and (new) putty formulations in vitro and in vivo in order to gain more insight in the characteristics of the materials.

The degradation characteristics of bioactive glass materials will be performed in vitro under different conditions. Physiological conditions will be compared to conditions that are mimicking inflammation (by a decrease in pH and/or an increase in temperature). Longitudinal follow-up will be performed with micro-CT analysis and evaluation of the media.

Mechanical properties will be both determined in vitro and in silico with the use of finite element analysis on patient specific high resolution peripheral quantitative CT (HR-pQCT) images. These images will be provided by Maastricht UMC+ and VieCuri Venlo.

Angiogenic potential will be studied in vitro. These studies focus on the formation of tubules by endothelial cells in contact with bioactive glasses. Within this angiogenesis tests not only S53P4 bioactive glass materials will be tested, but for comparison also other bioactive glass compositions (e.g. 45S5) will be evaluated on their angiogenic potential. 

 

This project is supported by WISE