The influences of molar intrusion on the inferior alveolar neurovascular bundle and root using the skeletal anchorage system in dogs

The skeletal anchorage system (SAS) was developed as intraoral rigid anchor s for open-bite correction by intrusion of molars. Since the application of SAS is a new modality in orthodontic treatment, the influences of radical molar intrusion on the root and the inferior alveolar neurovascular bundle were unknown. The purpose of this research is to verify the effect of molar intrusion on the neurovascular bundle, the level of osseointegration of bo ne screws, and root resorption. The results of this study showed mandibular molars were intruded 3.4 mm on the average over 7 months in dogs. The mini plates were well stabilized with osseointegrated bone screws and the peri-i mplant soft tissues showed slight inflammatory changes. Neither nerves nor blood vessels were damaged. Root resorption was observed but was repaired w ith new cementum. We concluded that the SAS utilizing transmucosal titanium miniplates as an immovable orthodontic anchorage could provide a new modal ity for molar intrusions without serious iatrogenic problems.