, Volume 62, Issue 2, pp 143–155 | Cite as

The static magnetic field accelerates the osteogenic differentiation and mineralization of dental pulp cells

Original Research


Dental pulp cells (DPCs) can differentiate into osteoblasts and are deemed a promising cell source for bone regeneration. Static magnetic field (SMF) stimulates osteoblast differentiation but the effect in DPCs remains unknown. The aim of this study was to investigate the effect of SMF exposure on the osteogenic differentiation and mineralization of rat DPCs in vitro. Cells were continuously exposed to SMF at 290 mT in the presence/absence of osteogenic induction [dexamethasone (Dex)/β-glycerophosphate (β-GP)]. Results showed that SMF alone did not impair the cell cycle and proliferation. On the other hand, obvious condensation in the metachromatic staining of the extracellular matrix with toluidine blue was observed for SMF-exposed cells as well as the Dex/β-GP treated cells. SMF in combination with Dex/β-GP significantly increased the mRNA expression of osteogenic genes, as well as the ALP activity and extracellular calcium concentration at the early stage, followed by obvious calcium deposits later. Besides, SMF exposure increased the activity of extracellular signal-regulated kinase 1/2 (ERK1/2) at 3 h and accelerated the mRNA expression of osteogenic transcription factor, Cbfa1, advancing its activation time from 168 to 72 h under osteogenic induction. In summary, SMF exposure in combination of Dex/β-GP induction could significantly accelerate the osteogenic differentiation and mineralization of DPCs.


Static magnetic field Dental pulp cells Dexamethasone Gene expression Mineralization 



This work was supported by the National Health Research Institutes and the National Science Council, Taiwan, Republic of China, and conducted in the Center of Tissue Engineering and Stem Cells Research of this university.


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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.Institute of Polymer Science and EngineeringNational Taiwan UniversityTaipei, TaiwanRepublic of China
  2. 2.Rehabilitation Engineering Research CenterNational Taiwan UniversityTaipei, TaiwanRepublic of China
  3. 3.Department of Life SciencesNational Chung Hsing UniversityTaichung, TaiwanRepublic of China

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