Orthodontic Correction of Bimaxillary Protrusion with Mini-screws in Class II Hyperdivergent Patient

Orthodontic Correction of Bimaxillary Protrusion with Mini-screws in Class II Hyperdivergent Patient

To achieve a harmonious profile with pleasant smile arc in Class II hyperdivergent adult cases has been a clinical challenge. Adequate retraction and intrusion of maxillary dentition as well as vertical control are the key factors to improve the smiling appearance and the facial profile. A 19-year-old female initially presented with lip protrusion, convex profile, retrusive chin, and a Class II malocclusion. The cephalometric analysis showed a Class II skeletal pattern (ANB = 9°) with high mandibular plane angle (SN-MP = 38°). The treatment plan included extraction of four first premolars for anterior teeth retraction as well as installation of three miniscrews in the maxilla as bony anchorage. Two miniscrews were placed into the infrazygomatic crest of the maxilla and one was inserted in the sub-apical region of maxillary incisors for retraction, intrusion, and torque control of anterior teeth. Bimaxillary protrusion was improved and a stable occlusal relationship was established after treatment. The total treatment duration was 24 months. Cephalometric analysis showed significant intrusion and retraction of maxillary incisors as well as a slight counterclockwise rotation of the mandible. This case demonstrated that the combined use of upper posterior and anterior miniscrews could be an effective manner to treat Class II hyperdivergent adult case with dentoalveolar protrusion.