A Case Of Orthodontic Treatment For Mandibular Retrusion In Adolescent

This case reports a two-stage orthodontic treatment of skeletal ClassⅡ malocclusion with mandibular retrusion. The patient finally achieves good dental arch shape, tooth alignment, skeletal face pattern and soft tissue profile. An adolescent male with complaints of malocclusion and teeth protrusion. The patient had the following problems: deep overjet, deep coverage, narrow maxillary arch, mandibular retraction, upper and lower anterior teeth with scattered gaps,E5, F5 not replaced, Annular Class II, Class I classification, bony Class II, even angle. The upper anterior gap was closed and the occlusion was opened by vestibular shield plus straight wire arch non-extraction two-phase sequential orthodontic treatment to establish molar neutrality and anterior overdenture-coverage relationship. In this case, the perioral muscle strength was altered by vestibular shield in the pre-growth peak period to release the upper arch stenosis and mandibular growth obstruction, together with the two-phase full-mouth straight-wire arch technique, which finally achieved a stable occlusion and aesthetic result. The scientific selection of early orthodontic timing, full-cycle sequential orthodontic treatment, continuous and stable force selection to guide the mandibular anterior movement, force control and overcorrection are the key points and difficulties in this case. Two-phase sequence orthodontic treatment is a scientific and efficient orthodontic treatment, especially for complex skeletal malocclusions. Through phased intervention, it not only improves the occlusal function and facial aesthetics of the patient, but also promotes the healthy development of the jaws.