Related Experiment Video
Updated: Jun 19, 2026
Using Inducible Osteoblastic Lineage-Specific Stat3 Knockout Mice to Study Alveolar Bone Remodeling During Orthodontic Tooth Movement
Published on: July 21, 2023
Local delivery of EGF-liposome mediated bone modeling in orthodontic tooth movement by increasing RANKL expression
José B Alves1, Cynthia L Ferreira, Aline F Martins
1Laboratory of Molecular Biology, University of Uberaba, Uberaba, MG, Brazil. propg.pr@uniube.br
Aims:
It has long been demonstrated that epidermal growth factor (EGF) has catabolic effects on bone. Thus, we examined the role of EGF in regulating mechanically induced bone modeling in a rat model of orthodontic tooth movement.
Main Methods:
The maxillary first molars of rats were moved mesially using an orthodontic appliance attached to the maxillary incisor teeth. Rats were randomly divided into 4 groups: (G1) administration of PBS (phosphate buffer saline) solution (n=24); (G2) administration of empty liposomes (n=24); (G3) administration 20ng of EGF solution (n=24); and (G4) 20ng of EGF-liposomes solution (n=24). Each solution was injected in the mucosa of the left first molar adjacent to the appliance. At days 5, 10, 14 and 21 after drug administration, 6 animals of each group were sacrificed. Histomorphometric analysis was used to quantify osteoclasts (Tartrate-resistant acid phosphatase (TRAP)+cells) and tooth movement. Using immunohistochemistry assay we evaluated the RANKL (receptor activator of nuclear factor kappaB ligand) and epidermal growth factor receptor (EGFR) expression.
Key Findings:
The EGF-liposome administration showed an increased tooth movement and osteoclast numbers compared to controls (p<0.05). This was correlated with intense RANKL expression. Both osteoblasts and osteoclasts expressed EGFR.
Significance:
Local delivery of EGF-liposome stimulates osteoclastogenesis and tooth movement.
