Novel ceramic bone replacement material Osbone® in a comparative in vitro study with osteoblasts.
OBJECTIVE
Hydroxyapatite (HA) is a very common ceramic material for bone replacement due to its similarity in composition to the mineral phase of natural bone. A recently developed bone graft material is Osbone(®), a synthetic HA ceramic available as porous granules with different sizes and block forms. The goal of this study was to characterise Osbone(®) in vitro in comparison to the already established calcium phosphate-based bone grafts Cerasorb M(®) and Bio-Oss(®).


METHODS
Adhesion and proliferation of SaOS-2 osteoblasts were evaluated quantitatively by determining DNA content and lactate dehydrogenase (LDH) activity and qualitatively by scanning electron microscopy (SEM). In addition, MTT cell vitality staining was performed to confirm the attachment of viable cells to the different materials. Osteogenic differentiation of the cells was evaluated by means of alkaline phosphatase (ALP) activity quantification as well as by gene expression analysis of osteogenic markers using reverse transcriptase PCR.


RESULTS
MTT staining after 1 day of adhesion showed viable cells on all examined materials. DNA content and LDH activity revealed proliferation of osteoblasts on Osbone(®) and Cerasorb M(®), but not on Bio-Oss(®) during cultivation over 28 days. SEM showed a well-spread morphology of cells attached to both Osbone(®) and Cerasorb M(®). We detected an increase of specific ALP activity during cultivation of osteoblasts on Osbone(®) and Cerasorb M(®) as well as expression of the bone-related genes ALP, osteonectin, osteopontin and bone sialoprotein II on both materials.


CONCLUSIONS
Osbone(®) granules support proliferation and osteogenic differentiation in vitro and are therefore promising candidates for in vivo applications.
Max Bergmann Center of Biomaterials and Institute for Materials Science, Technische Universität Dresden, Dresden, Germany. abernhardt@nano.tu-dresden.de
Anne
A
Bernhardt
Anja
A
Lode
Fabian
F
Peters
Michael
M
Gelinsky
D000469:Alkaline Phosphatase / Q000032:analysis; D018786:Bone Substitutes / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry; D002448:Cell Adhesion / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D049109:Cell Proliferation; D002470:Cell Survival / Q000502:physiology; D002516:Ceramics / Q000737:chemistry*; D004396:Coloring Agents; D004247:DNA / Q000032:analysis; D017886:Durapatite / Q000737:chemistry*; D006801:Humans; D058574:Integrin-Binding Sialoprotein / Q000032:analysis; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008903:Minerals / Q000737:chemistry; D010006:Osteoblasts / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology; D015676:Osteonectin / Q000032:analysis; D053495:Osteopontin / Q000032:analysis; D016062:Porosity; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013499:Surface Properties; D013778:Tetrazolium Salts; D013844:Thiazoles
C077540:Bio-Oss; D018786:Bone Substitutes; D002130:Calcium Phosphates; D004396:Coloring Agents; D058574:Integrin-Binding Sialoprotein; D008903:Minerals; D015676:Osteonectin; D013778:Tetrazolium Salts; D013844:Thiazoles; C485817:beta-tricalcium phosphate; D053495:Osteopontin; D004247:DNA; D017886:Durapatite; D007770:L-Lactate Dehydrogenase; D000469:Alkaline Phosphatase; C022616:thiazolyl blue