Biological regulation of orthodontic tooth movement, anchorage and retention

The purpose of the present study was to investigate the effect of transforming growth factor-β1(TGF-β1)，1，25-dihydroxyvitamine D I D 23 ii D2，24，25-dihydroxyvitamine D3 on relapse after experimental tooth movement in rats.Fifty five Sprague Dawley rats，6weeks old，were used for this experiment。The upper first molar was moved mesially with the magnitude of 20gf exerted by a ringlet。It took about48 days to obtain1 mm movement。The appliance them removed.10个D1-10个D1-10个D1-9个D1mol/L1，25-dihydroxyvitamine D D 23个D2，10个D1-8个D1-10个D1-5个D1mol/L24，25-dihydroxyvitamine D D23个D2或0.2-20 ng/ml TGF-β1was injected into the subperiosteum of upper first molar of animals of experimental groups every two days for 14days.Injection was initiated on2days prior to removal of the appliance and continued till 12days after the removal.24，25-dihydroxyvitamine D D 23个D2 treated group，和TGF-β1 treated group showed suppressive effects on the relapse after experimental too…More th movement compared with PBS treated group.The PBS treated group exhibited 0.60 mm relapse on12 days after removal of the appliance，while10 I D1-5个D 1 mol/L24，25-dihydroxyvitamine D I D 23个D 2 treated group showed 0.31 mm and 2 ng/ml TGF-β1 treated group showed 0.38 mm relapse，respectively。However，there was no significant difference between 1，25-dihydroxyvitamine D I D 23个D 2treated group and PBS treated group.Bone histomorphometrically，on the pressure side of the interradicular septum in 24，25-dihydroxyvitamine D I D 23个基因D2treated group and TGF-β1treated group，BV/TV and Ob.S/BS were significantly larger，and Oc.S/BS and was No.Oc/BS were significly larger，and Oc.S/BS and was No.Oc/BS were significantly larger，and Oc.S/BS and was No.On the tension side in 24，25-dihydroxyvitamine D I D 23 ii D2 treated group and TGF-β1treated group，BV/TV and ob.S/BS were significantly large，and No.Oc/BS was significantly smaller than those of PBS treated group.There was no significant difference between 1，25-dihydroxyvitamine D I D 23个D 2treated group and PBS treated group in BV/TV，Ob.S/BS，oc.S/Bs，and No.Oc/BS on both pressure and tension sides.These results suggest that the 24，25-dihydroxyvitamine D I D 23个D 2 and TGF-β1 inhibit bone resorption and stimulate bone formation of the alveolar bone during relapafter experimental tooth movement and couth.Less：Less

The purpose of the present study was to investigate the effect of transforming growth factor-β1 (TGF -β1), 1, 25-dihydroxyvitamine DィイD23ィエD2, 24, 25-dihydroxyvitamine D3 on relapse after experimental tooth movement in rats. Fifty five Sprague Dawley rats, 6 weeks old, were used for this experiment. The upper first molar was moved mesially with the magnitude of 20 gf exerted by a ringlet. It took about 48 days to obtain 1mm movement. The appliance them removed. 10ィイD1-10ィエD1〜10ィイD1-9ィエD1 mol/L 1, 25-dihydroxyvitamine DィイD23ィエD2, 10ィイD1-8ィエD1〜10ィイD1-5ィエD1 mol/L 24, 25-dihydroxyvitamine DィイD23ィエD2 or 0.2〜20ng/ml TGF -β1 was injected into the subperiosteum of upper first molar of animals of experimental groups every two days for 14 days. Injection was initiated on 2 days prior to removal of the appliance and continued till 12 days after the removal. 24, 25-dihydroxyvitamine DィイD23ィエD2 treated group, and TGF -β1 treated group showed suppressive effects on the relapse after experimental too … More th movement compared with PBS treated group. The PBS treated group exhibited 0.60 mm relapse on 12 days after removal of the appliance, while 10ィイD1-5ィエD1 mol/L 24, 25-dihydroxyvitamine DィイD23ィエD2 treated group showed 0.31 mm and 2 ng/ml TGF -β1 treated group showed 0.38 mm relapse, respectively. However, there was no significant difference between 1, 25-dihydroxyvitamine DィイD23ィエD2 treated group and PBS treated group.Bone histomorphometrically, on the pressure side of the interradicular septum in 24, 25-dihydroxyvitamine DィイD23ィエD2 treated group and TGF -β1 treated group, BV/TV and Ob.S/BS were significantly larger, and Oc.S/BS and was No.Oc/BS were significantly smaller than those of PBS treated group on 12 days after removal of the appliance. On the tension side in 24, 25-dihydroxyvitamine DィイD23ィエD2 treated group and TGF-β1 treated group, BV/TV and Ob.S/BS were significantly large , and No.Oc/BS was significantly smaller than those of PBS treated group. There was no significant difference between 1, 25-dihydroxyvitamine DィイD23ィエD2 treated group and PBS treated group in BV/TV, Ob.S/BS, Oc.S/Bs, and No.Oc/BS on both pressure and tension sides.These results suggest that the 24, 25-dihydroxyvitamine DィイD23ィエD2 and TGF -β1 inhibit bone resorption and stimulate bone formation of the alveolar bone during relapse after experimental tooth movement, and could be useful in preventing the orthodontic relapse. Less