The Application of the Ultrafine Technology in Improving the Biocompatibility and Osteo-inductivity of Dental Implants

Dental implants are very effective medical devices. However, although stable, the conventional titanium implants are not very bioactive which in some instances could reduce their efficacy. This thesis described the research progress of using polymeric ultrafine-particles with bioactive additives to enrich the surface of titanium substrate, thereby increasing the biocompatibility and osteo-inductivity of the biomaterial. During this doctoral project, three different types of polymers were examined, initially the conventional polyester, and later the novel epoxy as well as the epoxy/polyester hybrid polymers. Physical characterizations confirmed that all of the coating powders were ultrafine particles, and homogeneous surfaces were constructed from these particles with the correct incorporation of the functional and flow additives. The biocompatibility of the enriched surfaces were confirmed after examining their water contact angles, cell attachment/proliferation abilities, and their mitochondrial activities. After proliferation and differentiation, the osteo-inductivity of the surfaces were studied by labelling the mineral deposits that were formed on the surfaces. In addition to the biological performance, the adhesive strength of the enrichment layer was also assessed. After comparing between calcium oxide and calcium phosphate as the bioactive additive, and a series of different epoxy and polyester based polymers in the presence/absence of micron-sized TiO2, the results showed that the calcium oxide and micron-sized TiO2 containing epoxy/polyester hybrid surface was the best candidate for future clinical in vivo studies. From this study, a better understanding in the factors that affect the biocompatibility and osteo-inductivity of titanium substrate were obtained in order to create more effective biomaterials