Correcting the Anteroposterior Discrepancy of Class Ⅱ Patient with Overject by the Vertical Control of Miniscrew

Abstract

Background: While various orthodontic appliances were designed to manage the anteroposterior and vertical discrepancy, miniscrew was one of the powerful appliances and was widely utilized as anchorage to treatment the anteroposterior relationship. Method and Result: In the study we treated the severe Class Ⅱ skeletal discrepancy subject with protrude upper incisors and mandibular hypoplasia by the vertical control with the miniscrew. After two years treatment, all the objectives were achieved. The skeletal Class Ⅱ discrepancy was improved (ANB 6.3), the protrude upper incisors were treated (U1 angulation 92.8, U1-L1 120.7) and the occlusive plan was leveled (Occ Plane 8.2). Class Ⅰ molars and canines relationship were obtained. Conclusion: The vertical control was vital for the correction of anteroposterior discrepancy. The anteroposterior, vertical and transverse dimension and the time, especially the long term of post-treatment stability, interacts with each other.