caa a22 4500 475782755 CHVBK 20180406123649.0 cr unu---uuuuu 170329e20000301xx s 000 0 eng 10.1023/A:1008927624493 doi (NATIONALLICENCE)springer-10.1023/A:1008927624493 In vitro aging of a calcium phosphate cement [Elektronische Daten] [M. Bohner, H. Merkle, J. Lemai^tre] Cement samples made of β-tricalcium phoshate (β-TCP), phosphoric acid (PA) and water mixtures were incubated in several aqueous solutions to determine their stability over time. The effects of the cement composition and the incubating temperature were investigated in more detail. The cement samples contained mostly dicalcium phosphate dihydrate (DCPD) and remnants of β-TCP crystals. Depending on the initial cement composition, a certain amount of dicalcium phosphate (DCP) crystals were formed. The larger the initial PA concentration, the larger the DCP amount. After setting, the cement composition was stable for at least 16 days up to 60 °C. Above that temperature, the DCPD crystals decomposed into DCP crystals. The latter reaction provoked a decrease of the pH of the incubation solution, phenomenon expected for a cement sample containing an excess of PA. As the cement samples contained an excess of β-TCP, it was postulated that β-TCP crystals became so covered by DCP or DCPD crystals during setting that the setting reaction was stopped prematurely. The latter phenomenon gave a good explanation for the low pH values measured in the incubation solutions. ©©2000 Kluwer Academic Publishers Kluwer Academic Publishers, 2000 Bohner M. Pharmacy Department, Swiss Federal Institute of Technology of Zurich (ETHZ), Winterthurerstrasse 190, 8057, Zurich, Switzerland aut Merkle H. Pharmacy Department, Swiss Federal Institute of Technology of Zurich (ETHZ), Winterthurerstrasse 190, 8057, Zurich, Switzerland aut Lemai^tre J. Laboratory of Powder Technology, DMX, Swiss Federal Institute of Technology of Lausanne (EPFL), 1015, Lausanne, Switzerland aut Journal of Materials Science: Materials in Medicine Kluwer Academic Publishers 11/3(2000-03-01), 155-162 0957-4530 11:3<155 2000 11 10856 https://doi.org/10.1023/A:1008927624493 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1008927624493 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Bohner M. Pharmacy Department, Swiss Federal Institute of Technology of Zurich (ETHZ), Winterthurerstrasse 190, 8057, Zurich, Switzerland aut NATIONALLICENCE 700 1- Merkle H. Pharmacy Department, Swiss Federal Institute of Technology of Zurich (ETHZ), Winterthurerstrasse 190, 8057, Zurich, Switzerland aut NATIONALLICENCE 700 1- Lemai^tre J. Laboratory of Powder Technology, DMX, Swiss Federal Institute of Technology of Lausanne (EPFL), 1015, Lausanne, Switzerland aut NATIONALLICENCE 773 0- Journal of Materials Science: Materials in Medicine Kluwer Academic Publishers 11/3(2000-03-01), 155-162 0957-4530 11:3<155 2000 11 10856 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer