The aim of this thesis is to develop a method to produce melt-derived bioactive glass scaffolds, without the glass crystallizing into a glass-ceramic, while establishing an interconnected pore network suitable for bone tissue regeneration. In order to achieve this, the scaffold must have the ability to closely mimic the porous structure of cancellous bone and its mechanical properties. Two bioactive glasses were used in this project, both are modified from the Bioglass® composition: ICIE 16 (49.46% SiO2, 36.27% CaO, 6.6% Na2O, 6.6% K2O and 1.07% P2O5, all in mol%) and ICIE 16M (49.46% SiO2, 27.27% CaO, 6.6% Na2O, 6.6% K2O, 3% ZnO, 3% MgO, 3% SrO and 1.07% P2O5, all in mol%). Gel-cast foaming produced improved pore networks over alternative methods for producing porous scaffolds. There are many variables in the process. An initial protocol was established and each of the variables assessed systematically. The relationships between each component, the gelling time and the foam body volume were evaluated to develop an optimized protocol for the process. The size of the glass powder was critical in determining the sintering efficiency. A suitable drying and sintering program was also determined to prevent crystallization of the glass and formation of crystal species from by-products of the process. The scaffolds were characterized in terms of the interconnect size, the rate of hydroxycarbonate apatite (HCA) formation in simulated body fluid (SBF) solutions, the ion release rate and the compressive strength. The results showed that ICIE 16M sintered better and was stronger than ICIE 16, however in the bioactivity aspect of view, the rate of HCA formation in SBF was faster for ICIE 16 than ICIE 16M.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:530244 |
| Date | January 2010 |
| Creators | Wu, Zoe Yunxie |
| Contributors | Jones, Julian ; Hill, Robert |
| Publisher | Imperial College London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/10044/1/6410 |
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