Calcium phosphate-based systems doped with bioactive ions for applications as bone substitutes

Στολίδου, Δέσποινα

Calcium phosphate-based systems doped with bioactive ions for applications as bone substitutes

Date

2024-07-11

Authors

Στολίδου, Δέσποινα

Abstract

Throughout history, surgeons have strived to discover efficient methods for bone restoration, even in the absence of the required tools and materials for durable prosthetics. An early milestone in the field of bone grafting was achieved in the 17th century by van Meekeren[1], who successfully used a bone graft using a dog skull. After World War II, there were important developments in bio-materials, which led to their progression through three generations. The first generation focused on providing mechanical stability, the second generation aimed at integrating bioactivity for long-termprostheses, and the third generation specifically focused on biodegradability for bone regeneration.Advances in biomaterials technology are in progress, however, the problem of antimicrobial re-sistance (AMR) is still a major challenge. This issue is caused by the improper use of antibiotics andpresents significant hazards to public health. By the year 2050, infections associated with microbialresistance (AMR) are estimated to result in 10 million deaths per year and have significant eco-nomic consequences. This matter is of utmost importance for orthopedic procedures, requiring the use of alternatives to standard antibiotics. The research undertaken at the CIRIMAT laboratory(Toulouse, France) focused on synthesizing and improving the properties of nanocrystalline apatites, based on stoichiometric hydroxyapatite in which the constitutent ions were partly substitutedby one or more foreign ions. The ultimate objective was the enhance the antibacterial and bioactive properties of the apatitic minerals, as well as their ability to promote angiogenesis and osteogenesis. The present thesis aims to demonstrate the properties of doped core-shell biomimetic apatite particles with more than one metals, obtained using the three-fluid nozzle spray drying technique. This technique offers several functionalities to the prepared materials past their implantation and improves bone regeneration by controlling bioactivity. Moreover, it seemed to improve antimicrobial properties as well. Understanding the behavior of the novel biomineral compositions, necessities their as thorough as possible physicochemical and biological characterization.