The Study On The Effects And Mechanism Of The Magnetic Field On The Osteoblast

The orthodontist utilizes the force to make orthodontics, the force to the orthodontics is as the medicine to the physician; and the magnetic force is an important force which is still underdeveloped. With the development and utilization of magnetics, the orthodontics with magnetic force was widely carried out. The movement of the teeth is dependent on the bionomics of the alveolar bone; the osteoblast is the major effector cell and at the same time is the regulator of the osteoclast. Therefore, emphasis paid to the effect and mechanism of the magnetic magnetic field on the osteoblast is considered necessary and important to clarify the mechanism of orthodontics with magnetic force.There are few reports about the osteoblast's biological effects of the static magnetic field, and we have not seen the mechanism report of it.In this study, osteoblast cultures were exposed to static magnetic fields for different times with different density. The effects on the cell shape and the cell surface ultrastructure, cell proliferation, alkaline phosphatase (ALP), intracellular Ca²⁺ concentration, and the cytoskeleton of the static magnetic field were examined with molecular biology technology, electronic scanning microscope(SEM) and Laser Scanning Confocal Microscope(LSCM). The results showed as following:1. The pieces methods could culture many stable osteoblasts.2. No changes on the cell shape, cell growth and distribution were observed with inverted phase contrast microscope under the static magnetic field; but the scanning electric microscope observation showed that the static magnetic could result in the rebuilding of the cell surface ultrastructure, compared with the control group, experimental group showed more micirovili in the cell surface and some fused into vesicle.3. Different static magnetic field makes different proliferation effects on the osteoblast. Compared with the 8mT and 160mT static magnetic fields, which laten 24 hours and 48hours in promoting proliferation, the 50mT could keep on promoting proliferation from 24hours to 72huors.4. The static magnetic field could increase the ALP activity of osteoblast. Comared with the 8mT and 160mT static magnetic field, the 50mT static magnetic field make larger effect on increasing the osteoblast's ALP activity. With the lasting of the static magnetic field application, the ALP activity increasing extent decreased.5. The static magnetic field decreases the intracellular Ca²⁺ concentration within our experiment SMF density.6. The static magnetic field could result in the reorganization and rebuilding of the cytoskeleton of the osteoblast. After the application of the static magnetic field, the cytoskeleton protein upregulated and the cytoskeleton concentrated to the cellular nucleus.Based on these findings in the study, it was demonstrated that static magnetic fields with intensities of 8mT, 50mT and 160mT could increase the proliferation and ALP activity of the osteoblast. The static magnetic field may effect on the cell membrance, so as to evoke the Ca²⁺ pump in the membrance and drease the the intracellular Ca²⁺ concentration, thus result in the changes of the osteoblast's biological activity. Another mechanism is through the cytoskeleton, the static magnetic field transmitted the magnetic signal to the inner of the cell, thus lead to the changes of the osteoblast's biological activity.