Bioactivity: Mechanisms

Development of a synthetic tissue engineered three-dimensional printed bioceramic-based bone graft with homogenously distributed osteoblasts and mineralizing bone matrixin vitro

“…() demonstrated a beneficial effect of Si 4+ and Ca 2+ ionic dissolution products on osteoblast differentiation. Previously, we were able to show that the greater stimulatory effect on osteogenesis in vitro and in vivo observed with the silica containing CaOP material, which was used for fabricating the scaffolds in the current study, when compared to TCP and bioactive glass 45S5 as well as other CaOPs, was associated with simultaneous activation of the ERK‐differentiation, the PI3K cell survival and the alternate p38 pathways, which in its turn was positively correlated with silica and calcium release from the bioceramic as well as calcium uptake at the biomaterial surface (Knabe and Ducheyne ). Consequently, it may be speculated that the greater Si and Ca‐ion release noted with the RP scaffolds, when compared to the SSM scaffolds, may have had a beneficial effect on osteoblast differentiation and bone matrix formation in the present study, since a higher amount of cells and ECM formation was observed in RP scaffolds, when compared to SSM scaffolds, with these osteoblasts and newly formed bone matrix displaying greater OC expression, i.e.…”

“…an advanced maturation stage. Furthermore, previously we were able to demonstrate formation of a carbonated apatite surface and fibronectin serum protein adsorption after immersion of CaOP ceramics in physiologic solutions (Knabe and Ducheyne, ). The Ca–P‐rich zone under the adsorbed protein layer thickened as a result of continuous Ca and P diffusion.…”

“…In addition, histological findings of biopsies sampled from patients 6 months after sinus floor augmentation using this material confirm the excellent osteogenic properties of this material in the human case (Knabe et al ., ). This CaOP material has a higher solubility than TCP, and on this basis and as a result of the findings outlined above, can be regarded as excellent biodegradable bioactive alloplastic bone grafting material (Knabe & Ducheyne ; Knabe et al ., , , ).…”

“…The choice of this bioactive ceramic material for producing 3D scaffolds resulted from previous studies, in which this silica‐containing CaOP material had a greater stimulatory effect on osteoblast differentiation and bone formation in vitro and in vivo after implantation in a clinically relevant large animal model in the sheep mandible in combination with a greater biodegradability, when compared to clinically established bone grafting materials such as TCP and bioactive glass 45S5 (Knabe and Ducheyne, ; Knabe et al ., , , ). This was associated with simultaneous activation of the ERK‐differentiation, the PI3K cell survival and the alternative p38 pathways (Knabe and Ducheyne ). In addition, histological findings of biopsies sampled from patients 6 months after sinus floor augmentation using this material confirm the excellent osteogenic properties of this material in the human case (Knabe et al ., ).…”

“…the Ras/MAP kinase cell differentiation pathway, the PI3K/Akt‐cell survival pathway and the alternate p38 pathway. This was in addition to displaying an antiapoptotic effect (Knabe and Ducheyne, ). On this basis, this silica containing CaOP can be considered as excellent alloplastic material for alveolar ridge augmentation, mandibular and maxillary bone reconstructive surgery including bone tissue engineering approaches, which pursue generating individualized tissue‐engineered constructs that exactly match the shape of the patient's defect seen in the patient's computed tomographic (CT) data (Figure ) (Knabe et al ., 2008, ).…”