TY - JOUR A1 - Berger, Georg A1 - Mücke, Udo A1 - Harbich, Karl-Wolfram T1 - Determination of the internal surface of spongiosa-like ceramic scaffolds using light microscopy and X-ray refraction techniques JF - Key engineering materials N2 - This paper deals with spongiosa-like resorbable bone substitution material or scaffolds created by using Ca2KNa(PO4)6 as main crystalline phase. The material is prepared by melting, shock-cooling meanwhile the melt spontaneously crystallizes, milling to powder used to make a slip for PUR-sponge (Schwarzwalder process), and sintering. The spongiosa-like material is analyzed to characterize the pores but also the material surrounding the pores as well as the resulting internal surface by light microscopy and X-ray refraction technique, respectively. There is a big difference between the measured internal surface by the methods mentioned. Further investigations show that the differences are the result of powder particles that are not integrated in the sinter process. Introduction Ceramic scaffolds made of resorbable bone substitution material usefully have been appropriated as bone defect filling material as well as cell substrate. The spongiosa-like material was prepared using calcium phosphates consisting mainly of Ca2KNa(PO4)2 that is rapidly resorbable in comparison to tricalcium phosphate ceramics. For characterization of micro-structural parameters we used light microscopy image analysis and X-ray refraction technique. The later one enabled to determine characteristic microstructure parameters, i.e. spatially resolved internal surface densities and corresponding pore size distributions of spongiosa-like bioceramics. Methods The synthesis of glass-ceramics containing Ca2KNa(PO4)2 as the main crystalline phase has been described in detail elsewhere [1, 2]. T2 - 15th International Symposium on Ceramics in Medicine CY - Sydney, NSW, Australia DA - 2002-12-04 KW - Resorbable Ceramics KW - Ca2KNa(PO4)2 KW - Scaffolds KW - X-ray refraction technique KW - Internal surface PY - 2003 DO - https://doi.org/10.4028/www.scientific.net/KEM.240-242.469 SN - 1013-9826 VL - 240-242 SP - 469 EP - 472 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-2117 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Blaeß, Carsten A1 - Müller, Ralf A1 - Poologasundarampilai, G. A1 - Brauer, D. S. T1 - Sintering and concomitant crystallization of bioactive glasses JF - Journal of Applied Glass Science N2 - The sintering of bioactive glasses allows for the preparation of complex structures, such as three‐dimensional porous scaffolds. Such 3D constructs are particularly interesting for clinical applications of bioactive glasses in bone regeneration, as the scaffolds can act as a guide for in‐growing bone cells, allowing for good Integration with existing and newly formed tissue while the scaffold slowly degrades. Owing to the pronounced tendency of many bioactive glasses to crystallize upon heat treatment, 3D scaffolds have not been much exploited commercially. Here, we investigate the influence of crystallization on the sintering behavior of several bioactive glasses. In a series of mixed‐alkali glasses an increased CaO/alkali metal oxide Ratio improved sintering compared to Bioglass 45S5, where dense sintering was inhibited. Addition of small amounts of calcium fluoride helped to keep melting and sintering temperatures low. Unlike glass 13‐93, these new glasses crystallized during sintering but this did not prevent densification. Variation in bioactive glass particle size allowed for fine‐tuning the microporosity resulting from the sintering process. KW - Bioactive glass KW - Crystallization KW - Scaffolds KW - Sintering PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-485458 DO - https://doi.org/10.1111/ijag.13477 SN - 2041-1286 VL - 10 IS - 4 SP - 449 EP - 462 PB - Wiley AN - OPUS4-48545 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -