Nonsurgical correction using miniscrew-assisted vertical control of a severe high angle with mandibular retrusion and gummy smile in an adult

摘要

Orthodontic treatment in adult patients with a skeletal discrepancy can be challenging. In this case report, we achieved both sagittal and vertical control by combining the classic sliding mechanics straight-wire technique with miniscrew anchorage. We treated a 21-year-old Chinese woman with a severe high mandibular plane angle, a retrusive chin, and a gummy smile. Her diagnosis included a skeletal Class II skull base with a mild anterior open bite, a protrusive maxilla, and a backwardly rotated mandible. This case underscores the importance of anchorage control in both the sagittal and vertical directions. First, we used miniscrews in the maxillary and mandibular buccal segments to obtain rigid anchorage. Next, we achieved good anterior and posterior vertical control with miniscrews in the maxillary anterior labial and posterior buccolingual segments. Intrusion of the maxillary molars contributed to deepening of the anterior overbite and counterclockwise rotation of the mandibular plane, which, in turn, improved the facial profile. Intrusion of the maxillary incisors contributed to correction of the gummy smile. After 1 year of retention, the patient had a stable, well-aligned dentition with ideal intercuspation and an improved facial contour. Our results thus suggest that placement of miniscrews in the anterior and posterior regions of the maxilla is effective for camouflaging a high-angle skeletal Class II defect. This technique requires minimal patient compliance and is particularly useful for correction of a high angle in an adult with a gummy smile.