Exposure duration: continuous for 4 h/day during 6 months
|Exposure duration||continuous for 4 h/day during 6 months|
|Setup||two pairs of Helmholtz coils with a diameter of 70 cm and 125 turns of insulated soft copper wire with a diameter of 1.5 mm, coils placed vertically at a distance of 47 cm inside a 130 cm x 65 cm x 80 cm Faraday cage; rats kept in 43 cm x 42 cm x 15 cm methacrylate boxes|
|Sham exposure||A sham exposure was conducted.|
|magnetic flux density||1.5 mT||-||measured||-||-|
In all experimental groups (groups 2-4), some histopathological changes such as irregular appearance in bone marrow cavities were observed, while the structure in the control group appeared normal. In the ovariectomized rats (groups 2 and 4), a loss in bone marrow was determined, while there was an increased amount of bone marrow in the rats exposed to magnetic field alone (group 3). In both magnetic field exposed groups (groups 3 and 4), a disruption and latency in the calcification and ossification was observed. However, no significant differences occurred in the thickness of the condylar cartilage layers between the groups.
The authors conclude that long-term exposure to extremely low frequency magnetic fields and the ovariectomy could induce histopathological changes in the rat's mandibular condyle. However, magnetic field exposure had no influence on the ovariectomy-induced changes.