Disputas: Hanna Tiainen
M. sc. Hanna Tiainen ved IKO vil forsvare sin avhandling for graden ph.d.: Ceramic TiO2 Scaffolds for Bone Repair
Tid og sted for prøveforelesning
- Professor, PhD Jonathan Knowles, UCL Eastman Dental Institute, University College London, London (førsteopponent)
- Professor, PhD Kärlis-Agris Gross, Institute of Biomaterials and Biomechanics, Riga University, Riga (andreopponent)
- Førsteamanuensis dr.odont. Bente Brokstad Herlofson, komiteens leder
- Dekan Pål Barkvoll, Det odontologisk fakultet, Universitetet i Oslo
- Professor Ståle Petter Lyngstadaas, Det odontologiske fakultet, Universitetet i Oslo
- Senioringeniør Ph.d. Håvard Jostein Haugen, Det odontologiske fakultet, Universitetet i Oslo
Synthetic bone scaffolds can be used in assisting the repair and regeneration of bone tissue in critical size bone defects. Such bone scaffolds need to meet several chemical, physical, and pore architectural requirements in order to facilitate optimal conditions for unobstructed bone tissue regeneration. Reticulated ceramic TiO2 foams can potentially fulfil many of these requirements, and thus, it was hypothesised that with appropriate processing history, TiO2 foams may provide a suitable three-dimensional template for the formation of viable bone tissue in a load-bearing physiological environment. Therefore, the main objective of the research work was to produce ceramic TiO2 scaffolds with appropriate physical, structural, and surface chemical properties for providing a favourable microenvironment for promoting osteogenesis in applications where moderate mechanical support is required, such as maxillofacial and dental applications.
The produced TiO2 foams were found to exhibit pore architectural features that closely resemble the structural morphology of highly porous human trabecular bone tissue, and which are well-matched with those required from a bone scaffold, namely high porosity, appropriate pore size distribution, and well-interconnected pore volume. When combined with the excellent biocompatibility of the ceramic TiO2, the highly interconnected pore structure also provided a favourable microenvironment for bone formation, which was manifested by the ingrowth of large quantity of viable mineralised bone tissue within the porous TiO2 scaffold structures in vivo. As one of the most important prerequisite for a bone scaffold structure is the sufficient permeability of the pore network, the excellent osteoconductive capacity of the TiO2 scaffolds was attributed to the highly interconnected pore network that allows maximal volume for vascularisation and tissue ingrowth, while still facilitating sufficient structural support at the bone defect site.