Investigations into silicate-substituted hydroxyapatite (Si-HA) were performed. The aqueous precipitation method produced phase pure Si-HA with modi cations to the method causing impurities in the material. A novel study using Raman spectroscopy followed the behaviour of the silicate ions and provided a new interpretation regarding silicate substitution. The silicate ions created interactions with hydroxyl ions, initially, which reduced upon sintering of the material. As the silicate ions do not behave inde- pendently in the HA structure initially, suggests that these interactions may contribute to the bioactivity of Si-HA. Also industrial aspects of Si-HA were investigated regarding the silicate reagent (TEOS). A small di erence of 1% in the percentage concentration of TEOS was not negligible and caused a decrease in the amount of silicate substituted into HA. Di erent brands and grades of TEOS did produce Si-HA with similar structural properties. Therefore, a variety of brands and grades of TEOS can be used and thus the most cost e ective choice can be made. The rst analytical investigations into the molecular arrangement of fully mineralised osteoarthritic (OA) and osteoporotic (OP) bone were performed through small angle neutron scattering (SANS) studies. This study provided a description for the molecular arrangement of collagen molecules, along the lateral plane, regarding the molecular di- ameter and the packing of these molecules into the bril by the development of a model based on SANS theory. The collagen molecules behave like a 2-dimensional liquid-like system. Through the development of the model, the rst written solution for the struc- ture factor for a system of hard-disks was stated. This study provided an understanding into how collagen molecules are arranged in OA and OP bone. Also, compositional studies iterated possible di erences between the organic content of OA and OP bone. Thus the organic content of bone may play a role in the bone disorders.

Diss. (sammanfattning) Umeå : Univ., 2003. / Härtill 5 uppsatser.