Objective Calcium phosphate cements are in clinical use for filling non-load bearing bone defects in crania- andmaxiofacial surgery. Two types of cements are distinguishable: cement formed at pH values lower than form brushier (DCPD) and above pH values of 4.2 they form hydroxyapatite (HA), the mineral component of bone and teeth. Cements are thermodynamically non-restorable due to the stability of HA under physiological conditions. Degradation is only possible by acid producing bone remodelling cells (osteoclasts) and is limited to the surface since cells cannot penetrate the cement. In contrast, brushier cements areresorbable under physiological conditions, because brushier has a much higher solubility product at pH7.4 compared to HA. This has been demonstrated in vivo. Up to now, no commercial brushier bone cements are available for clinical use, largely because of its comparatively low mechanical strength. The rate of crystal growth rate of brushier is 500 times that offhand and therefore these cements set very rapidly. Compressive strengths of brushier cements reported in literature are lower than 10 Map and setting times can just be increased to values of 3-5 minutes by these of retardants at the price of further reduction in the already low mechanical properties. Furthermore, unrelated components can lead to a low pH in the implant site, which raises toxicity concerns in some implantation sites, e.g. the spine. Clearly however if mechanical properties can be improved brushier cements will offer the substantial advantage of being restorable and hence replaceable by new bone. The overall aim of this project will be to investigate the powder physics of this cement system in order that mechanical performance and handling characteristics are improved. Surface charge modifiers and liquefiers will be used to further enhance these improvements. Fields of science engineering and technologymaterials engineeringcrystalsmedical and health sciencesclinical medicinesurgerynatural scienceschemical sciencesinorganic chemistryalkaline earth metalsengineering and technologyindustrial biotechnologybiomaterialsengineering and technologymaterials engineeringceramics Keywords Bone Graft Calcium Phosphate Cement Craniofacial Surgery Programme(s) FP6-MOBILITY - Human resources and Mobility in the specific programme for research, technological development and demonstration "Structuring the European Research Area" under the Sixth Framework Programme 2002-2006 Topic(s) MOBILITY-2.1 - Marie Curie Intra-European Fellowships (EIF) Call for proposal FP6-2002-MOBILITY-5 See other projects for this call Funding Scheme EIF - Marie Curie actions-Intra-European Fellowships Coordinator THE UNIVERSITY OF BIRMINGHAM EU contribution No data Address Edgbaston BIRMINGHAM United Kingdom See on map Total cost No data
