パルス電磁場刺激の家兎大腿骨インプラント埋入モデルへの応用

第2報新生骨形成状態の経時的変化の観察

抄録

Osteogenesis promotion during bone repair following placement of an endosseous implant may reduce the time required for initial implant fixation, permitting early seating of the superstructure. Prosthodontically, this may provide significant benefits by promoting early restoration of the occlusion.
Pulsing electromagnetic fields (PEMFs) were applied to the oral implants of 9 adult male Japanese white rabbits (experimental group), and 9 unstimulated rabbits were used as controls. Implants were inserted into bilateral femurs. PEMFs were applied at a magnetic intensity of 0.2mT, a pulse width of 25μEsec, and a pulse frequency of 100Hz. The duration of stimulation was 8 hours per day. The rabbits were sacrificed at 1, 2, or 4 weeks after implantation. The results were analyzed using a basic fuchsin-methylene blue double stain, contact microradiography, fluorescent labeling, and computer image analysis.
The experimental group showed a tendency to increase new bone formation compared to the control group one week after implantation. This tendency became significant by 2 weeks after implantation. Promotion of osteogenesis did not significantly differ from that seen in the control group 4 weeks after implantation. These findings showed that PEMFs are effective for promoting new bone formation during the early stages after implantation.