Nanostructured Hybrid Materials for Bone Implants Fabrication

Bone is one of the few tissues capable of self-regeneration during skeletal deficiency, but this regeneration is limited by the nature and size of the defect. In general, skeletal deficiency occurs as a result of trauma, tumor, bone disease, or abnormality. In the case of severe fracture, bone will not heal by itself. For this reason, artificial bone substitutes may be required to restore routine function without damaging living tissue, and the selection of the bone graft substitute is the most important factor for better performance in vivo. 

Natural bone grafts would appear to provide the ideal material. However, autografts are necessarily limited in volume and xenografts or allografts should be considered with caution due to the potential risk for transmission of viruses or other non-conventional agents [6]. For these reasons, there has been a growing 

Bio-inorganic Hybrid Nanomaterials. Edited by E. Ruiz-Hitzky, K. Ariga, Y. M. Lvov Copyright 2008 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 978-3-527-31718-9 

There are two types of bone (a) compact or cortical bone and (b) trabecular or cancellous bone. Cortical bone is found principally in the shafts (diaphyses) of long bones. It consists of a number of irregularly spaced overlapping cylindrical units termed Haversian systems. Each consists of a central Haversian canal surrounded by concentric lamellae of bony tissue. Trabecular bone is found principally at the ends of long bones and flat bones. It is composed of a meshwork of trabeculae within which 

The skeleton consists of approximately 80 % cortical bone and 20 % trabecular bone, mainly in the axial skeleton. These amounts vary according to site and relate to the need for mechanical support. While trabecular bone accounts for the minority of total skeletal tissue, it is the site of greater bone turnover because its total surface area is greater than that of cortical bone. 

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Nanostructured Hybrid Materials for Bone Implants Fabrication... 

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