Disputas: Hanna Tiainen

Tid og sted for prøveforelesning

29. mai 14.15, Auditorium I, Geitmyrsveien 69

Bedømmelseskomité

• 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

Disputasleder

• Dekan Pål Barkvoll, Det odontologisk fakultet, Universitetet i Oslo

Veiledere

• Professor Ståle Petter Lyngstadaas, Det odontologiske fakultet, Universitetet i Oslo
• Senioringeniør Ph.d. Håvard Jostein Haugen, Det odontologiske fakultet, Universitetet i Oslo

Sammendrag

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.