Abstract
Although pulsed electromagnetic fields (PEMFs) have been used for treatments of nonunion bone fracture healing for more than three decades, the underlying cellular mechanism of bone formation promoted by PEMFs is still unclear. It has been observed that a series of parameters such as pulse shape and frequency should be carefully controlled to achieve effective treatments. In this article, the effects of PEMFs with repetitive pulse burst waveform on the cellular activity of SaOSβ2 osteoblastβlike cells were investigated. In particular, cell proliferation and mineralization due to the imposed PEMFs were assessed through direct cell counts, the MTT assay, tissue nonspecific alkaline phosphatase (ALP) and Alizarin Red S (ARS) staining. PEMF stimulation with repetitive pulse burst waveform did not affect metabolic activity and cell number. However, the ALP activity of SaOSβ2 cells and mineral nodule formation increased significantly after PEMF stimulation. These observations suggest that repetitive pulse burst PEMF does not affect cellular metabolism; however, it may play a role in the enhancement of SaOSβ2 cell mineralization. We are currently investigating cellular responses under different PEMF waveforms and Western blots for protein expression of bone mineralization specific proteins. Bioelectromagnetics 29:125β132, 2008. Β© 2007 WileyβLiss, Inc.