resumo
New bone cements made of Sr-substituted brushite-forming a-tricalcium phosphate (alpha-TCP) were prepared and characterized in the present work The quantitative phase analysis and structural refinement of the starting powders and of hardened cements were performed by X-ray powder diffraction and the Rietveld refinement technique Isothermal calorimetry along with setting time analysis allowed a precise tracing of the setting process of the pastes The pastes showed exothermic reactions within the first 10-15 min after mixing and further release of heat after about I h An apatitic phase formed upon immersion of the hardened cements in simulated body fluid for 15 and 30 days due to the conversion of brushite into apatite confirming their in vitro mineralization capability. The compressive strength of the wet cement specimens decreased with increasing curing time, being higher in the case of Sr-substituted CPC. The results suggest that the newly developed Sr-substituted brushite-forming alpha-TCP cements show promise for uses in orthopaedic and trauma surgery such as in filling bone defects (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd All rights reserved.
palavras-chave
CALCIUM-PHOSPHATE CEMENTS; TRICALCIUM PHOSPHATE; CRYSTAL-STRUCTURE; BRUSHITE CEMENTS; PARTICLE-SIZE; STRONTIUM; HYDROXYAPATITE; REACTIVITY; KINETICS; POLYMERIZATION
categoria
Engineering; Materials Science
autores
Pina, S; Torres, PM; Goetz-Neunhoeffer, F; Neubauer, J; Ferreira, JMF
nossos autores
José Maria da Fonte Ferreira
Professor(a) Jubilado(a)
Paula Maria da Costa Torres
Investigador Auxiliaragradecimentos
Thanks are due to CICECO for Support and to the Portuguese Foundation for Science and Technology for the fellowship grant of S.P (SFRH/BD/21761/2005).; The authors gratefully acknowledge the financial support from GRICES-DAAD The authors would like to thank Ch. Stabler and D. Jansen, Institute of Mineralogy, University of Erlangen-Nuremberg, for experimental support and helpful discussions