TY - CONF A1 - Berger, Georg T1 - Calciumphosphat-Keramik für den resorbierbaren Knochenersatz T2 - Jahrestagung der Deutschen Keramischen Gesellschaft 2007 CY - Dresden, Germany DA - 2007-03-19 PY - 2007 AN - OPUS4-15863 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Berger, Georg T1 - Schnell resorbierbare, offenporige Knochenersatzwerkstoffe auf Basis von Calciumphosphaten T2 - Symposium "Materialforschung für Innovation in der Region Berlin/Brandenburg" CY - Potsdam, Germany DA - 2007-09-27 PY - 2007 AN - OPUS4-15864 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kalbe, Ute A1 - Berger, Wolfgang A1 - Simon, Franz-Georg A1 - Eckardt, Jürgen A1 - Christoph, Gabriele T1 - Results of interlaboratory comparisons of column percolation tests N2 - Laboratory leaching tests may be used for source term determination as a basis for risk assessment for soil–groundwater pathway (leachate forecast) on contaminated sites in Germany. Interlaboratory comparisons on the evaluation of the reproducibility of column percolation tests were conducted within the framework of an integrated R + D program using three waste reference materials. The interlaboratory comparisons of column percolation tests showed good reproducibility of the results for inorganic and organic parameters as well as for the accompanying parameters. This is due to the stipulations concerning the time of contact between leachant and sample material as well as the sample placement in the columns. Different column dimensions used by the participants of the interlaboratory comparisons did not have any substantial influence on the column test results. KW - Leachate forecast KW - Column percolation tests KW - Interlaboratory comparisons KW - Contaminated soil KW - Waste material PY - 2007 DO - https://doi.org/10.1016/j.jhazmat.2007.03.039 SN - 0304-3894 VL - 148 IS - 3 SP - 714 EP - 720 PB - Elsevier CY - Amsterdam AN - OPUS4-15754 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Franz-Georg A1 - Berger, Wolfgang A1 - Mantyk, Matthias T1 - Rückgewinnung von Kupfer aus Rostaschen aus der thermischen Abfallbehandlung KW - Flotation KW - Ressourcen KW - Rostasche PY - 2007 SN - 0026-0746 VL - 61 IS - 11 SP - 713 PB - Giesel Verlag GmbH CY - Isernhagen AN - OPUS4-16122 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knabe, C. A1 - Houshmand, A. A1 - Berger, Georg A1 - Ducheyne, P. A1 - Gildenhaar, Renate A1 - Kranz, I. A1 - Stiller, M. T1 - Effect of rapidly resorbable bone substitute materials on the temporal expression of the osteoblastic phenotype in vitro N2 - Ideally, bioactive ceramics for use in alveolar ridge augmentation should possess the ability to activate bone formation and, thus, cause the differentiation of osteoprogenitor cells into osteoblasts at their surfaces. Therefore, in order to evaluate the osteogenic potential of novel bone substitute materials, it is important to examine their effect on osteoblastic differentiation. This study examines the effect of rapidly resorbable calcium-alkali-orthophosphates on osteoblastic phenotype expression and compares this behavior to that of β-tricalcium phosphate (TCP) and bioactive glass 45S5. Test materials were three materials (denominated GB14, GB9, GB9/25) with a crystalline phase Ca2KNa(PO4)2 and with a small amorphous portion containing either magnesium potassium phosphate (GB14) or silica phosphate (GB9 and GB9/25, which also contains Ca2P2O7); and a material with a novel crystalline phase Ca10[K/Na](PO4)7 (material denominated 352i). SaOS-2 human bone cells were grown on the substrata for 3, 7, 14, and 21 days, counted, and probed for an array of osteogenic markers. GB9 had the greatest stimulatory effect on osteoblastic proliferation and differentiation, suggesting that this material possesses the highest potency to enhance osteogenesis. GB14 and 352i supported osteoblast differentiation to the same or a higher degree than TCP, whereas, similar to bioactive glass 45S5, GB9/25 displayed a greater stimulatory effect on osteoblastic phenotype expression, indicating that GB9/25 is also an excellent material for promoting osteogenesis. KW - Bone substitute materials KW - Calcium-alkali-orthophosphate ceramics KW - SaOS-2 cells KW - Osteoblast differentiation KW - Bioactive glass PY - 2008 DO - https://doi.org/10.1002/jbm.a.31383 SN - 1549-3296 SN - 1552-4965 VL - 84A IS - 4 SP - 856 EP - 868 PB - Wiley CY - Hoboken, NJ AN - OPUS4-16658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dombrowski, Felix A1 - Marx, Heidi A1 - Ploska, Ute A1 - Nicolaides, Dagmar A1 - Stiller, M. A1 - Knabe, C. A1 - Berger, Georg T1 - Solubility and ingrowth behaviour of degradable and figuline calcium alkaline phosphate cements N2 - The thrust of the investigations presented here is to point out the degradation behaviour in vitro and the ingrowth behaviour in vivo of four different calcium alkaline phosphate cements. Two of the figuline and mouldable composites consist of the crystalline phase Ca2KNa(PO4)2 and two of the crystalline phase Ca10[K/Na](PO4)2 each containing 2wt% medium gel strength porcine gelatin. Furthermore A-TCP was added to both Ca10[K/Na](PO4)2 cements as a hardening supporting reactant. The testing material groups differ in small amorphous portions containing either silica phosphate (GB9), magnesium potassium phosphate (GB14) or diphosphates (401545 and 401545(70)). The respective composites show a monomodal particle size distribution (d50~7µm; span~4) and an average total porosity around 28vol%.For the solubility studies cylindrical samples (d=6mm; h=12mm) were stored in a 0.1mol TRIS buffer solution and incubated at 37°C for maximum 50 weeks. The storage solution was analysed and renewed every week. The results are plotted cumulative. For the in vivo studies critical size defects were dissected to mandibles in a sheep model in which a 1cm³ area of the bottom of the mandibles was surgically resected and replaced with the figuline cements whereas the mouldability allows the reconstruction of the original outer contour without draining off even when replacing upside down. KW - Calcium alkaline phosphate cement KW - Gelatin KW - Figuline KW - Solubility KW - Ingrowth behavior PY - 2012 DO - https://doi.org/10.4028/www.scientific.net/KEM.493-494.387 SN - 1013-9826 VL - 493-494 SP - 387 EP - 390 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-24924 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dombrowski, Felix A1 - Hoffmann, Rita A1 - Ploska, Ute A1 - Marx, Heidi A1 - Berger, Georg T1 - Investigations on degradable and figuline calcium alkaline phosphate cements with multimodal particle size distribution N2 - The paper presented here deals with rheological and hardening properties during the setting reaction, and density and compressive strength after the final setting of a figuline composite consisting of Ca2KNa(PO4)2 and 2wt% medium gel strength gelatin. Compared to the composite with monomodal particle size distribution (d50=7.18µm; span=3.9) and its properties during and after setting reaction, the goal of this work is to increase the resulting product compressive strength by mixing different particle sizes in order to obtain bi- and trimodal distributions. For the bimodal powder mixtures the ratio in diameter (dcourse/dsmall) was chosen with 7/1 and volume ratio dcourse/dsmall was 70/30%. For the trimodal powder mixtures the ratio in diameter (dcourse/dmedium/dsmall) was chosen with 70/7/1 and volume ratio dcourse/dmedium/dsmall was set to 44/28/28%.After establishing an adequate crushing and sieving process the tap density and powder density of each fraction was determined. Subsequently, the different particle sizes were mixed and the densities and the Hausner ratio were determined again. The mixtures show an increase in both densities especially the tap density increased significantly. Rheological investigations show that the graphs of storage and loss moduli of the multimodal powder mixtures respectively are similar. The characteristic setting times show a slight decrease compared with the monomodal composite but not significantly different data. When comparing the resulting compressive strength of cylindrical samples, which were stored direct after reaching the initial setting time under physiological conditions, the studies illustrated in all cases for the multimodal mixtures a significant increase in compressive strength and a higher density. KW - Calcium alkaline phosphate cement KW - Gelatin KW - Compressive strength KW - Figuline KW - Particle size PY - 2012 DO - https://doi.org/10.4028/www.scientific.net/KEM.493-494.355 SN - 1013-9826 VL - 493-494 SP - 355 EP - 360 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-24925 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gildenhaar, Renate A1 - Knabe, C. A1 - Wirth, Cynthia A1 - Linow, Ulf A1 - Houshmand, A. A1 - Berger, Georg T1 - Calcium alkaline phosphate scaffolds for bone regeneration 3D-fabricated by additive manufacturing N2 - Calcium alkaline phosphate granulates can be used for substitution of several bone defects but for the reconstruction of large skeletal parts in the maxillofacial and orthopaedic fields fitted scaffolds are preferable. Within the additive manufacturing methods, the 3D printing process offers exciting opportunities to generate defined porous scaffolds. We used a R1 printer from ProMetal Company, USA, for producing scaffolds directly from a ceramic powder. For this direct free form fabrication technology the powder has to possess a lot of specific properties both for the generation of a stable green body and also for the subsequent sintering preparation. For this printing process we prepared different granules in a fluidized bed process containing Ca2KNa(PO4)2 as main crystalline phase. Granules were characterized by different methods and several sieve fractions were used for preparing disc like and cylindrical parts. The suitability of granules for this printing process was determined by porosity and strength of produced bodies. Next to granules' performance both of these properties can be directly influenced by 3D printing process parameters. With knowledge of suitable process parameters scaffolds with different porosity in a respective desired design can be created. In this study, cylindrical scaffolds with graded porosity were produced for bone regeneration of segmental defects in maxillofacial surgery and dental implantology by tissue engineering. KW - 3D printing KW - Calcium alkaline phosphates KW - Ceramic scaffolds KW - Oral surgery PY - 2012 DO - https://doi.org/10.4028/www.scientific.net/KEM.493-494.849 SN - 1013-9826 N1 - Geburtsname von Wirth, Cynthia: Gomes, C. M. - Birth name of Wirth, Cynthia: Gomes, C. M. VL - 493-494 SP - 849 EP - 854 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-24989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Quillard, S. A1 - Mellier, C. A1 - Gildenhaar, Renate A1 - Hervelin, J. A1 - Deniard, P. A1 - Berger, Georg A1 - Bouler, J.-M. T1 - Raman and infrared studies of substituted ß-TCP N2 - Several substituted β-tricalcium phosphates have been prepared with different cations (monovalent, divalent and trivalent) and at various levels of substitution. Structural investigations have proved that fewer than ~10% wt substitution, the substituted compounds are isostructural to β-TCP, leading to solid solutions. These samples have been characterized by infrared and Raman spectroscopies. The vibrational spectra show mainly the bands related to the vibrations of PO43- tetrahedrons present in the structure. As Raman scattering and infrared absorption are local probes, the bands are sensitive to the local environment of the distinct tetrahedrons, related to the site of substitution and to the nature of the cations. KW - Tricalcium phosphates KW - Ionic substitution KW - Vibrational spectroscopies PY - 2012 DO - https://doi.org/10.4028/www.scientific.net/KEM.493-494.225 SN - 1013-9826 VL - 493-494 SP - 225 EP - 230 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-24954 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Franz-Georg A1 - Holm, Olaf A1 - Berger, Wolfgang T1 - Resource recovery from urban stock, the example of cadmium and tellurium from thin film module recycling N2 - Raw material supply is essential for all industrial activities. The use of secondary raw material gains more importance since ore grade in primary production is decreasing. Meanwhile urban stock contains considerable amounts of various elements. Photovoltaic (PV) generating systems are part of the urban stock and recycling technologies for PV thin film modules with CdTe as semiconductor are needed because cadmium could cause hazardous environmental impact and tellurium is a scarce element where future supply might be constrained. The paper describes a sequence of mechanical processing techniques for end-of-life PV thin film modules consisting of sandblasting and flotation. Separation of the semiconductor material from the glass surface was possible, however, enrichment and yield of valuables in the flotation step were non-satisfying. Nevertheless, recovery of valuable metals from urban stock is a viable method for the extension of the availability of limited natural resources. KW - Flotation KW - Cadmium KW - Tellurium KW - Thin film technology KW - Sand blasting PY - 2013 DO - https://doi.org/10.1016/j.wasman.2012.12.025 SN - 0956-053X VL - 33 IS - 4 SP - 942 EP - 947 PB - Pergamon Press CY - New York, NY AN - OPUS4-29312 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Berger, Georg A1 - Mensing, M. A1 - Müller-Mai, C. A1 - Gross, U. A1 - Rahmanzadeh, R. A1 - Sittinger, M. T1 - Bioresorbable carriers for subchondral anchoring of tissue-engineered cartilage in articular defects T2 - 3rd Biennial Meeting of the Tissue Engineering Society International (TESI) CY - Lake Buena Vista, FL, USA DA - 2000-11-30 PY - 2000 AN - OPUS4-1042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Berger, Georg A1 - Ploska, Ute A1 - Gross, U. A1 - Mesgarian, M. A1 - Müller-Mai, Ch. A1 - Voigt, C. T1 - Tissue response in the femur of rabbits after implantation of a new calcium titanium phosphate composition KW - Bone Bonding KW - Calcium Titanium Phosphate KW - Coated Implants KW - Tissue Response PY - 2001 SN - 1013-9826 VL - 192-195 SP - 383 EP - 386 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-1044 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Berger, Georg A1 - Ploska, Ute A1 - Willmann, G. T1 - Hydroxyapatite's Solubility May Cause Loosening of Coated Implants KW - pH Value KW - Solubility KW - Coated Implants KW - Hydroxyapatite PY - 2001 SN - 1013-9826 VL - 192-195 SP - 111 EP - 114 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-1045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Berger, Georg A1 - Ploska, Ute A1 - Willmann, G. T1 - Auflösung von Hydroxylapatit-Beschichtung durch Entzündung PY - 2001 SN - 1616-0177 SN - 0011-8656 VL - 2 IS - 2-3 SP - - PB - Verl. Neuer Merkur CY - München AN - OPUS4-1142 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Berger, Georg T1 - Spongiosa-artige Formkörper und poröse Folien aus Calciumphosphat-Keramiken T2 - Statusseminar Bio-Med.Net - Tissue Engineering und zellbasierte Therapie in der Region Berlin CY - Berlin, Deutschland DA - 2001-06-29 PY - 2001 SP - 7 EP - 8 AN - OPUS4-1151 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klaffke, Dieter A1 - Berger, Georg A1 - Hartelt, Manfred T1 - Tribologische Untersuchungen an anorganischen Implantatwerkstoffen PY - 2002 SN - 1616-0177 SN - 0011-8656 VL - 3 IS - 1 SP - 42 EP - 47 PB - Verl. Neuer Merkur CY - München AN - OPUS4-1332 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ploska, Ute A1 - Berger, Georg T1 - A new long-term stable biomaterial containing Apatite and Calcium-Zirconium-Orthophosphate PY - 2002 SN - 0957-4530 SN - 1573-4838 VL - 13 IS - 12 SP - L54 PB - Springer CY - Norwell, Mass. AN - OPUS4-1421 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hitzegrad, Frank A1 - Berger, Georg A1 - Ploska, Ute A1 - Öchsner, A. T1 - Comparison of static and dynamical analysis material properties of opencell ZrO2 foams T2 - Materials Week 2002 ; European Congress on Advanced Materials, their Processes and Applications ; 6th International Conference on Joining Ceramics, Glass and Metal CY - Munich, Germany DA - 2002-09-30 PY - 2002 SN - 3-88355-314-X PB - Werkstoff-Informationsges. AN - OPUS4-1462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hitzegrad, Frank A1 - Berger, Georg T1 - Untersuchung viskoelastischer Eigenschaften von porösen biokeramischen Werkstoffen und Bestimmung der durch applikationsbedingten Medieneinfluss verursachten Eigenschaftsänderungen T2 - Kolloquium des Lehrstuhls für Technische Mechanik CY - Erlangen, Deutschland DA - 2002-07-15 PY - 2002 AN - OPUS4-1463 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hitzegrad, Frank A1 - Berger, Georg A1 - Ploska, Ute A1 - Oechsner, A. ED - Claussen, N. T1 - Comparison of static and dynamic material properties of spongiosa-like bioceramics T2 - 8th International Conference on Ceramic Processing (ICCPS-8) CY - Hamburg, Germany DA - 2002-09-02 PY - 2004 SN - 0955-2219 VL - 24 IS - 2 PB - Elsevier CY - Orlando, FL AN - OPUS4-1464 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Berger, Georg A1 - Acil, Y. A1 - Jepsen, S. A1 - Spitzer, Andrea T1 - Rapidly resorbable and spongiosa-like dicalcium potassium sodium phosphate glass-ceramics for three-dimensional cultivation of human osteoblast-like cells T2 - 14th International Symposium on Ceramics in Medicine ; Annual meeting of the International Society for Ceramics in Medicine CY - Palm Springs, CA, USA DA - 2001-11-14 PY - 2002 UR - http://www.scientific.net/1013-9826/ SN - 1013-9826 VL - 218-220 SP - 233 EP - 236 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-1934 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gross, U. A1 - Müller-Mai, C. A1 - Voigt, C. A1 - Berger, Georg A1 - Spitzer, Andrea T1 - In Vivo Tests of a Highly Porous Rapidly Resorbable Dicalcium Potassium Sodium Phosphate Glass-Ceramics N2 - Glass-ceramics containing Ca2KNa(PO4)2 as the main crystalline phase have a solubility which is 8 times higher than that of alpha-tricalcium phosphate ceramics. When using these compositions in drug delivery systems, especially in bone, it is necessary to create a material with a high open porosity. A Ca2KNa(PO4)2-based glass-ceramic was prepared from a borosilicate glass melt. The processed material includes minor amounts of boron which are low enough for medical application. Tissue response was studied using an animal model. Particles were implanted in rabbit femurs. Bone and soft tissue development occurred at the particle interfaces. In general, most particles were enclosed in the network of trabecular bone. The advantages of using a biomaterial with high porosity (pore size of 1-3 micron), together with rapid biodegradation, bioactivity and biocompatibility, despite traces of boron, were shown. 4 refs. T2 - 14th International Symposium on Ceramics in Medicine CY - Palm Springs, CA, USA DA - 2001-11-14 PY - 2002 DO - https://doi.org/10.4028/www.scientific.net/KEM.218-220.307 SN - 1013-9826 VL - 218-220 SP - 307 EP - 310 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-1935 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -