Studies on Biomineralisation Leading to the Preparation of a New Bio Inorganic Composite for Bone Substitution

Abstract

The scope of the present investigation was to: Achieve at phase transitions using the calcium phosphate salt di calcium dihydrate Ca HPO4. 2H20. Preparation and characterization of the new bone graft device using a prepared collagen introduced into the calcifying solution for crystal growth. Evaluation of this new substitute material in vivo. Improvement of this material by coating with osseoinductive protein - A BMP like protein isolated form ossein, demineralized bone. Results obtained can be tabulated as follows: Phase transitions of the di calcium phosphate was achieved by changes in pH which eventually brought about changes in saturation. The phase changed form the di calcium salt to octa calcium salt to hydroxyapatite. An anti-microbial system was developed to facilitate phase transitions and bring about crystal growth on any organic matrix on introduction into the aqueous system, without significant microbial degradation of the organic matrices so introduced. These results were further confirmed through the Fourier transform infra red spectroscopic studies, Differential calorimetric studies and the Scanning electron micrographic studies (Chapter 2). The new Bone Graft Device (BGD) was prepared by initially preparing the denatured collagen web and introducing the same into calcifying solutions for crystal growth. The gross architecture of this new composite goes parallel to the scheme of architecture of cancellous bone in vivo (Chapter 3). The new bone graft device so engineered was evaluated for its osseoinductive capacity and gross biocompatability with in vivo studies done in canines. The material proved to be compatible, as it did not evince any serious antigenic reactions and osseoconduction inferred from the results of harvested tissue from the experimental dogs (canines) (chapter 4). To improve on the new design focusing on the osseoinductive nature of the composite the material was coated with a new bone morphogenetic protein isolated from a new source through a newly designed procedure (chapter 5).