The clinical evaluation of the effect of traditional attachment and optimized attachment on maxillary teeth movement in patients with extracted first premolar teeth

Abstract Background: The purpose of this study was to compare the effects of G6 optimized attachment and traditional attachment on maxillary teeth movement in patients with first premolar extraction. Methods: In this study, 29 patients who received 4 first premolar extraction treatment with Invisalign (Align Technology) and completed the first series of aligners were included. Superimposition of pretreatment and predicted posttreatment dental models was acquired from ClinCheck software. By superimposing skull models and dental models, the final superimposition of the pretreatment and posttreatment dental models were obtained. Posttreatment and predicted posttreatment three-dimensional teeth movements of the maxillary central incisors, canines, second premolars and first molars were compared between the two groups using paired t-tests, respectively, and the differences between two groups were compared using independent samples t-tests. Results: Compared to the predicted changes, the maxillary central incisors achieved greater distal rotation and palatal inclination and extrusion. The maxillary canines achieved greater distal rotation, distal tipping and extrusion. The maxillary second premolars achieved less distal tipping and intrusion. The maxillary first molars achieved greater buccal inclination and less distal tipping and intrusion. For the comparison of teeth movement achieved between the two groups, there was a significant difference in changes in torque and buccolingual displacement of the maxillary central incisors and angulation of the maxillary canines between the traditional attachment group and the G6 optimized attachment group. Conclusions: There are differences between traditional attachments and G6 optimized attachments in controlling the torque and buccolingual displacement of the maxillary central incisors, as well as the axial angulation of the canines.