Abstract:

BACKGROUND: Self-locking bracket appliance is small in size, comfortable, and conducive to the protection of the oral hygiene, which has gained more and more attention from orthodontists.
OBJECTIVE: To investigate the role of different orthodontic appliances in the histopathological changes in rabbit periodontal tissue in the tension side.
METHODS: Totally 64 healthy rabbits were selected to establish the animal model of orthodontic tooth movement, and then were randomly divided into four groups: control group, MBT appliance group, Begg appliance group, and Damon III appliance group. The appliance was ligated between the maxillary incisor and the first molar, pulling the 1-mm mesial movement of the maxillary first molar.
RESULTS AND CONCLUSION: At 14 days of appliance application, trabecular bone volume and trabecular width were significantly increased, the trabecular space became narrower, and the number of osteoblasts and osteoclasts was dramatically increased in the MBT appliance group, Begg appliance group, and Damon Ⅲ appliance group as compared with the control group (P < 0.05). At 21 days, Damon Ⅲ appliance had a superior effect over the MBT appliance and Begg appliance in trabecular bone volume, trabecular width, trabecular space and the number of osteoblasts and osteoclasts (P < 0.05). These findings indicate that in the initial phase of orthodontic tooth movement, MBT appliance, Begg appliance, and Damon Ⅲ appliance all have orthodontic effects, and furthermore, Damon Ⅲappliance is better than the MBT appliance and Begg appliance in the late stage.