engleski

Characterisation of Calcium Phosphate-based Bone Substitution Materials by Electron Paramagnetic Resonance Spectroscopy

Ionic substitutions have been proposed as a tool to improve the biological performance of calcium phosphate based ceramics (E. Boanini, M. Gazzano, A. Bigi, Acta Biomaterialia 6 (2010) 1882). Particular attention was focused on the cations: Mg, Zn, and Mn. 14 different synthetic and biological bone substitution materials were characterized recently by x-ray, infra-red and scanning electron microscopy and the main parameters: chemical composition, crystalinity and morphology were found strongly different as compared with natural bone samples (as reference for autologous bone) (D. Tadic, M. Epple, Biomaterials 25 (2004) 987). In this work Electron Paramagnetic Resonance (EPR) spectroscopy was used to detect paramagnetic ions like: Mn2+ and Fe3+ (I. Mayer, F.Cuisinier, I. Popov, Y. Schleich, S. Gdalya, O. Burghaus, D. Reinen, Eur. J. Inorg. Chem. 2006 (2006) 1460) as well as, the point defects (T. Murata, K. Shiraishi, Y. Ebina, T. Miki, Appl. Radiat. Isot. 47 (1996) 1527) in the calcium phosphate materials present on the market. The EPR study of the paramagnetic species in these biomaterials may be considered as a probe to investigate structural details in synthetic bone graft substitutes. Paramagnetic species Mn2+, Fe3+, and hydrogen atoms detected in the ten different bone substitute materials were compared with synthetic hydroxyapatite and beta tricalcium phospate. The results suggest that analysis of the biomaterials with EPR spectroscopy should be included after synthesis, design, manufacturing and sterilization of products as complementary method to check the biocompatibility.

electron paramagnetic resonance; dental implantology; biomaterials

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