TY - JOUR A1 - Knabe, C. A1 - Stiller, M. A1 - Kampschulte, M. A1 - Wilbig, Janka A1 - Peleska, B. A1 - Günster, Jens A1 - Gildenhaar, R. A1 - Berger, G. A1 - Rack, A. A1 - Linow, U. A1 - Heiland, M. A1 - Rendenbach, C. A1 - Koerdt, S. A1 - Steffen, C. A1 - Houshmand, A. A1 - Xiang-Tischhauser, L. A1 - Adel-Khattab, D. T1 - A tissue engineered 3D printed calcium alkali phosphate bioceramic bone graft enables vascularization and regeneration of critical-size discontinuity bony defects in vivo N2 - Recently, efforts towards the development of patient-specific 3D printed scaffolds for bone tissue engineering from bioactive ceramics have continuously intensified. For reconstruction of segmental defects after subtotal mandibulectomy a suitable tissue engineered bioceramic bone graft needs to be endowed with homogenously distributed osteoblasts in order to mimic the advantageous features of vascularized autologous fibula grafts, which represent the standard of care, contain osteogenic cells and are transplanted with the respective blood vessel. Consequently, inducing vascularization early on is pivotal for bone tissue engineering. The current study explored an advanced bone tissue engineering approach combining an advanced 3D printing technique for bioactive resorbable ceramic scaffolds with a perfusion cell culture technique for pre-colonization with mesenchymal stem cells, and with an intrinsic angiogenesis technique for regenerating critical size, segmental discontinuity defects in vivo applying a rat model. To this end, the effect of differing Si-CAOP (silica containing calcium alkali orthophosphate) scaffold microarchitecture arising from 3D powder bed printing (RP) or the Schwarzwalder Somers (SSM) replica fabrication technique on vascularization and bone regeneration was analyzed in vivo. In 80 rats 6-mm segmental discontinuity defects were created in the left femur. KW - Additive Manufacturing KW - Bio active ceramic KW - In-vivo KW - Alcium alkali phosphate PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584555 DO - https://doi.org/10.3389/fbioe.2023.1221314 SN - 2296-4185 VL - 11 SP - 1 EP - 20 PB - Frontiers SA CY - Lausanne AN - OPUS4-58455 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Adel-Khattab, D. A1 - Giacomini, F. A1 - Gildenhaar, R. A1 - Berger, G. A1 - Gomes, Cynthia A1 - Linow, Ulf A1 - Hardt, M. A1 - Peleska, B. A1 - Günster, Jens A1 - Stiller, M. A1 - Houshmand, A. A1 - Ghaffar, K. A1 - Gamal, A. A1 - El-Mofty, M. A1 - Knabe, C. T1 - Development of a synthetic tissue engineered three- dimensional printed bioceramic-based bone graft with homogenously distributed osteoblasts and mineralizing bone matrix in vitro N2 - Over the last decade there have been increasing efforts to develop three-dimensional (3D) scaffolds for bone tissue Engineering from bioactive ceramics with 3D printing emerging as a promising technology. The overall objective of the present study was to generate a tissue engineered synthetic bone graft with homogenously distributed osteoblasts and mineralizing bone Matrix in vitro, thereby mimicking the advantageous properties of autogenous bone grafts and facilitating usage for reconstructing segmental discontinuity defects in vivo . To this end, 3D scaffolds were developed from a silica-containing calcium alkali orthophosphate, using, fi rst, a replica technique – the Schwartzwalder – Somers method – and, second, 3D printing, (i.e. rapid prototyping). The mechanical and physical scaffold properties and their potential to facilitate homogenous colonization by osteogenic cells and extracellular bone matrix formation throughout the porous scaffold architecture were examined. Osteoblastic cells were dynamically cultured for 7 days on both scaffold types with two different concentrations of 1.5 and 3 × 10⁹ cells/l. The amount of cells and bone matrix formed and osteogenic marker expression were evaluated using hard tissue histology, immunohistochemical and histomorphometric analysis. 3D-printed scaffolds (RPS) exhibited more micropores, greater compressive strength and silica release. RPS seeded with 3 × 10⁹ cells/l displayed greatest cell and extracellular Matrix formation, mineralization and osteocalcin expression. In conclusion, RPS displayed superior mechanical and biological properties and facilitated generating a tissue engineered synthetic bone graft in vitro, which mimics the advantageous properties of autogenous bone grafts, by containing homogenously distributed terminally differentiated osteoblasts and mineralizing bone matrix and therefore is suitable for subsequent in vivo implantation for regenerating segmental discontinuity bone defects. KW - Bone tissue engineering KW - Calcium alkali orthophosphate KW - Rapid prototyping KW - Scaffold KW - Mandible PY - 2017 DO - https://doi.org/10.1002/term.2362 SN - 1932-6254 SN - 1932-7005 VL - 12 IS - 1 SP - 44 EP - 58 PB - Wiley Online Library AN - OPUS4-40745 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller-Mai, C.M. A1 - Berger, Georg A1 - Stiller, M. A1 - Gildenhaar, Renate A1 - Jörn, Daniela A1 - Ploska, Ute A1 - Houshmand, A. A1 - Bednarek, A. A1 - Koch, C. A1 - Knabe, C. T1 - Evaluation of degradable bone cements for percutaneous augmentation of bone defects KW - Bone defect KW - Bioactive bone cement KW - Calcium alkali orthophosphates KW - Histology KW - Histomorphometry KW - Knochendefekt KW - Bioaktiver Knochenzement KW - Calciumalkaliorthophosphat KW - Histologie KW - Histomorphometrie PY - 2010 DO - https://doi.org/10.1002/mawe.201000706 SN - 0933-5137 SN - 1521-4052 VL - 41 IS - 12 SP - 1040 EP - 1047 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-22891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lopez-Heredia, M.A. A1 - Gildenhaar, Renate A1 - Berger, Georg A1 - Linow, Ulf A1 - Wirth, Cynthia A1 - Günster, Jens A1 - Houshmand, A. A1 - Stiller, M. A1 - Knabe-Ducheyne, C. T1 - Effect of stressed and unstressed cell culture environments on the viability of MC3T3 cells with calcium phosphates T2 - ISACB-6 - International symposium on apatite and correlative biomaterials CY - Nantes, France DA - 2013-06-05 KW - Cell culture media KW - Fetal bovine serum KW - Stressed KW - Unstressed KW - Calcium alkaline orthophosphates PY - 2013 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-299387 DO - https://doi.org/10.4172/2090-5025.S1-002 SN - 2090-5017 SN - 2090-5025 N1 - Geburtsname von Wirth, Cynthia: Gomes, C. M. - Birth name of Wirth, Cynthia: Gomes, C. M. SP - 1 EP - 3(?) PB - Ashdin AN - OPUS4-29938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stiller, M. A1 - Rack, A. A1 - Zabler, S. A1 - Goebbels, Jürgen A1 - Dalügge, O. A1 - Jonscher, S. A1 - Knabe, C. T1 - Quantification of bone tissue regeneration employing Beta-tricalcium phosphate by three-dimensional non-invasive synchrotron micro-tomography - A comparative examination with histomorphometry KW - Sinus floor augmentation KW - Histomorphometry KW - Synchrotron micro-tomography KW - Multi-dimensional microscopy KW - Histovolumetry PY - 2009 DO - https://doi.org/10.1016/j.bone.2008.10.049 SN - 8756-3282 VL - 44 IS - 4 SP - 619 EP - 628 PB - Elsevier CY - New York, NY, USA AN - OPUS4-22888 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dombrowski, Felix A1 - Ploska, Ute A1 - Berger, Georg A1 - Gildenhaar, Renate A1 - Stiller, M. A1 - Knabe, C. ED - Kim, Sukyoung T1 - Rheological investigations on degradable and figuline calcium alkaline phosphate cements T2 - 22nd International symposium on ceramics in medicine (Bioceramics 22) CY - Daegu, Korea DA - 2009-10-26 KW - Rheology KW - Calcium alkaline phosphate cement KW - Gelatine KW - Composite PY - 2009 SP - 863 EP - 866 AN - OPUS4-20287 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rack, A. A1 - Stiller, M. A1 - Nelson, K. A1 - Knabe, C. A1 - Rack, T. A1 - Zabler, S. A1 - Dalügge, O. A1 - Riesemeier, Heinrich A1 - Cecilia, A. A1 - Goebbels, Jürgen T1 - Ex vivo and in vitro synchrotron-based micro-imaging of biocompatible materials applied in dental surgery N2 - Biocompatible materials such as porous bioactive calcium phosphate ceramics or titanium are regularly applied in dental surgery: ceramics are used to support the local bone regeneration in a given defect, afterwards titanium implants replace lost teeth. The current gold standard for bone reconstruction in implant dentistry is the use of autogenous bone grafts. But the concept of guided bone regeneration (GBR) has become a predictable and well documented surgical approach using biomaterials (bioactive calcium phosphate ceramics) which qualify as bone substitutes for this kind of application as well. We applied high resolution synchrotron microtomography and subsequent 3d image analysis in order to investigate bone formation and degradation of the bone substitute material in a three-dimensional manner, extending the knowledge beyond the limits of classical histology. Following the bone regeneration, titanium-based implants to replace lost teeth call for high mechanical precision, especially when two-piece concepts are used in order to guaranty leak tightness. Here, synchrotron-based radiography in comparison with classical laboratory radiography yields high spatial resolution in combination with high contrast even when exploiting micro-sized features in these kind of highly attenuating objects. Therefore, we could study micro-gap formation at interfaces in two-piece dental implants with the specimen under different mechanical load. We could prove the existence of micro-gaps for implants with conical connections as well as to study the micromechanical behavior of the mating zone of conical implants during loading. The micro-gap is a potential issue of failure, i. e. bacterial leakage which can induce an inflammatory process. T2 - SPIE Conference 7804 - Developments in X-ray tomography VII CY - San Diego, CA, USA DA - 2010-08-02 KW - Microtomography KW - Synchrotron radiation KW - Radiography KW - Dental implants KW - Bioceramics KW - Implant-abutment interface PY - 2010 DO - https://doi.org/10.1117/12.858435 SN - 0277-786X N1 - Serientitel: SPIE proceedings series – Series title: SPIE proceedings series VL - 7804 SP - 78040E-1 - 78040E-8 AN - OPUS4-22731 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jörn, Daniela A1 - Gildenhaar, Renate A1 - Berger, Georg A1 - Stiller, M. A1 - Knabe, C. T1 - Behaviour of calcium alkali orthophosphate cements under simulated implantation conditions KW - Calcium alkali orthophosphates KW - Calcium phosphate cement KW - Compressive strength KW - Setting times PY - 2009 SN - 1013-9826 VL - 396-398 SP - 213 EP - 216 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-17881 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knabe, C. A1 - Berger, Georg A1 - Gildenhaar, Renate A1 - Ducheyne, P. A1 - Stiller, M. T1 - Novel, rapidly resorbable bioceramic bone grafts produce a major osteogenic effect - the pre-clinical evidence KW - Calcium phosphates KW - Bone substitute materials KW - Bioactive ceramics KW - Biodegradability PY - 2010 DO - https://doi.org/10.4028/www.scientific.net/AST.76.214 SN - 1662-0356 VL - 76 SP - 214 EP - 223 PB - Techna CY - Faenza AN - OPUS4-22028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rack, A. A1 - Rack, T. A1 - Stiller, M. A1 - Riesemeier, Heinrich A1 - Zabler, S. A1 - Nelson, K. T1 - In vitro synchrotron-based radiography of micro-gap formation at the implant-abutment interface of two-piece dental implants N2 - Micro-gap formation at the implant-abutment interface of two-piece dental implants was investigated in vitro using high-resolution radiography in combination with hard X-ray synchrotron radiation. Images were taken with the specimen under different mechanical loads of up to 100 N. The aim of this investigation was to prove the existence of micro-gaps for implants with conical connections as well as to study the mechanical behavior of the mating zone of conical implants during loading. Synchrotron-based radiography in comparison with classical laboratory radiography yields high spatial resolution in combination with high contrast even when exploiting micro-sized features in highly attenuating objects. The first illustration of a micro-gap which was previously indistinguishable by laboratory methods underlines that the complex micro-mechanical behavior of implants requires further in vitro investigations where synchrotron-based micro-imaging is one of the prerequisites. KW - X-ray imaging KW - Dental implants KW - Digital radiography KW - Implant-abutment interface PY - 2010 DO - https://doi.org/10.1107/S0909049510001834 SN - 0909-0495 SN - 1600-5775 VL - 17 IS - 2 SP - 289 EP - 294 PB - Blackwell Publishing CY - Oxford AN - OPUS4-22121 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gildenhaar, Renate A1 - Berger, Georg A1 - Lehmann, Erhard A1 - Stiller, M. A1 - Koch, C. A1 - Ducheyne, P. A1 - Rack, A. A1 - Seligmann, H. A1 - Jonscher, S. A1 - Knabe, C. T1 - A comparative study of the biodegradability of calcium-alkali-orthophosphate ceramics in vitro and in vivo KW - Calcium-alkali-orthophosphate KW - Solubility KW - Biodegradability PY - 2007 SN - 1013-9826 VL - 330-332 SP - 63 EP - 66 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-14528 LA - eng 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 -