Purpose: To study the changes of expression of signal transducer and activator of transcription 3 (STAT3) during orthodontic tooth movement (OTM).
Methods: Twenty six-week-old SD rats were selected, the upper left first molars were moved by coil spring and lasted for 7 days. The maxillary tissues were obtained at 0, 1, 3, 7 d and subjected to histological study. Statistical analysis was performed using SPSS 16.0 software package.
Results: The main changes in alveolar bone during orthodontic tooth movement included significant increase in osteoblast number and bone formation in the tension area, and bone resorption in the pressure area. The positive cells of osteocalcin in the tension area increased during OTM. The expression of STAT3 increased in the tension area at 3 d and 7 d in comparison with that at 0 d.
Conclusions: Orthodontic force can stimulate alveolar bone remolding. The expression of STAT3 in the tension area may have effects on alveolar bone remolding during orthodontic tooth movement.