The effects of pulsed and sinusoidal electromagnetic fields on E-cadherin and type IV collagen in gingiva: a histopathological and immunohistochemical study.

BACKGROUND The potential beneficial effects of extremely low frequency pulsed and sinusoidal electromagnetic fields have been shown on many tissues. Gingival epithelium plays an important role in immunosurveillance of the periodontal tissues. The epithelium acts as a mechanical barrier through cell junctions such as E-cadherin. OBJECTIVES Investigation of the effects of extremely low frequency magnetic fields on gingiva. MATERIAL AND METHODS Twenty-seven male Wistar albino rats were used. The rats were divided into three groups: control group (n = 9), SEMF group (n = 9), PEMF group (n = 9). The SEMF and PEMF (pulse time: 25 µsn, pulse frequency: 50 Hz) groups were subjected to 1.5 mT, 50 Hz, exposure 6 h a day, 5 days a week for 28 days in methacrylate boxes. The gingival tissue pieces processed for routine histological and immunohistochemical examination and tissue sections were stained with H-E and Masson trichrome. In addition, E-cadherin and type IV collagen expressions were examined immunohistochemically. RESULTS Intraepithelial lymphocytes and proliferation of epithelial cells increased in both electromagnetic field groups. The over-expressions of E-cadherin on gingival epithelium was detected in the PEMF and SEMF groups. The expression level of type IV collagen was not significant between the control and electromagnetic field treated groups, except for a significant increase in the basal cell layer of the PEMF group, as compared to the control and SEMF groups. CONCLUSIONS PEMF and SEMF have a local pro-inflammatory effect on gingiva, leading to an increase in E-cadherin level but not type IV collagen. Both PEMF and SEMF can be used as a supportive device in the treatment of gingival diseases, especially those which lead to defects in the epithelial barrier.