OBJECTIVETo establish a novel in-vitro culture device simulating distraction osteogenesis, and to understand the the changes of cytoskeleton of osteoblasts under different magnitudes of mechanical distraction.

METHODSA novel in-vitro culture device simulating distraction osteogenesis was developed with titanium and silicon membrane. The expressions of F-actin cytoskeleton subjected to different magnitudes of distraction were observed in situ under a confocal laser scanning microscope, and protein levels of actin and tubulin alpha were analyzed by electrophoresis of Western blot.

RESULTSThe mode of culture device simulating distraction osteogenesis was similar to that of distraction osteogenesis used in clinic. After 24 h mechanical distraction with physiological magnitude, F-actin of osteoblasts was organized and paralleled to the direction of distraction forces. After 24 h mechanical distraction with hyperphysiological magnitude, however, F-actin of osteoblasts became reorganized and disrupted, and protein levels of actin and tubulin alpha decreased.

CONCLUSIONSThe novel in vitro culture device simulating distraction osteogenesis is suitable for the study of distraction osteogenesis in vitro. Physiological mechanical distraction causes organization and rearrangement of actin cytoskeleton. However, hyperphysiological mechanical distraction results in reorganization and disruption of actin cytoskeleton.