Researches on bone defects are focused on the use of composites due to the
composite and well-organized hierarchical structure of the bone. In this study,
it is aimed to develop Polycaprolactone based implants with different organic & / #8211 / DBM, HYA- and/or inorganic & / #8211 / bioglass, calcium sulfate- compositions for
augmenting bone healing.
Bioactivity of the discs was evaluated by scanning electron microscopy and
EDS analysis after incubation in SBF for 1, 7 and 14 days. All bioglass
containing groups showed apatite molecules at different incubation times.
Degradation studies demonstrated that only PCL/BG/HYA discs had fast
degradation upon incubations in PBS (4 and 6 weeks). Initial mechanical
properties of composites were found to be directly related to the composition.
However, decreases in disc mechanical properties were also obtained in the
same order with the amount of water uptake at composite groups.
According to biocompatibility studies investigated with cytotoxicity tests on
Saos-2 cells, all groups, except the HYA involving one were found as
biocompatible.
After in vivo application of discs to critical size defects on rabbit humeri (for 7
weeks), their efficacy on healing was studied with computerized tomography,
SEM and biomechanical tests. The results revealed that bone-implant
interface formation has started for all groups with high bone densities at the
interface of implant groups compared to empty defect sites of negative
controls. Also the healing was suggested to be gradual from bone to implant
site as microhardness values increased at regions closer to bone. However,
regeneration was found to not reach to healthy bone levels.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/2/12608785/index.pdf |
| Date | 01 September 2007 |
| Creators | Erdemli, Ozge |
| Contributors | Tezcaner, Aysen |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | M.S. Thesis |
| Format | text/pdf |
| Rights | To liberate the content for METU campus |
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