Nonsurgical treatment of a Class III malocclusion with maxillary skeletal retrusion using rapid maxillary expansion and reverse pull headgear.

The patient demonstrated a Class III malocclusion with 30% overbite, 1 mm overjet, a centered upper dental midline, and a lower dental midline 2 mm to the left. She had a straight profile, a protrusive lower lip, and an interlabial gap of 3 mm (Figs. 1, 2, and 3). Space analysis indicated approximately 5.5 mm maxillary and 3 mm mandibular space deficiency. The maxillary arch was constricted. Radiographs revealed all third molars developing normally in their crypts. The patient had an ANB angle of –4°, an SNA angle of 72°, an SNB angle of 76°, an SN-MP angle of 31°, and an FMA angle of 21° (Fig. 4). The maxillary incisors were 7 mm anterior to the N-A line with an angle to SN of 102°, whereas the mandibular incisors were positioned on the N-B line with an angle to FH of 77°. There was a slight shift anteriorly when the patient was manipulated from centric relation to centric occlusion. These findings were consistent with a diagnosis of Class III malocclusion with maxillary skeletal retrusion.