Comparison of a magnetic treatment system combined with miniscrews and a conventional NiTi spring for tooth movement and bone formation: A Beagle model study.

BACKGROUND: The Magnetic Treatment System Combined with Miniscrews (MTSCM) is a novel orthodontic appliance designed to deliver continuous and stable forces for tooth movement while enhancing alveolar bone remodelling. This study evaluated the efficacy and biological effects of MTSCM compared with conventional NiTi spring in a Beagle dog model.

METHODS: Twelve Beagle dogs underwent extraction of the mandibular first and second premolars and truncation of the ipsilateral maxillary canine crowns. Animals were randomly assigned to three groups: MTSCM group (M group), conventional NiTi spring group (N group), and control group. Cone-beam computed tomography (CBCT) was performed before and after force application to assess tooth movement. Bone remodelling was evaluated by tetracycline double fluorescence labelling, haematoxylin and eosin (HE) staining, and tartrate-resistant acid phosphatase (TRAP) staining.

RESULTS: The MTSCM generated stable forces ranging from 60 to 160g. Both M and N groups showed significant reductions in the distance between the mandibular third premolar and canine compared to the control group (P<0.001), with greater displacement and less inclination in the M group. Bone mineral deposition rates and osteoblast counts were significantly higher in the M group than in the N group (P<0.001), indicating enhanced bone formation. Osteoclast counts were also elevated in both experimental groups, with the M group showing more TRAP-positive cells than the N group (P<0.01), suggesting intensified bone remodelling under magnetic stimulation.

CONCLUSIONS: MTSCM promotes efficient, controlled tooth movement and enhances bone remodelling, suggesting promising clinical applications in orthodontic treatment.