Case Report Figure 3. Initial lateral cephalogram and panoramic radiograph Radiographic Findings A panoramic radiograph shows that the patient's maxillary right and left wisdom teeth are congenitally missing along with his maxillary left second premolar (UL5), and his maxillary right second premolar and mandibular third molars are developing. The lateral cephalometric tracing shows a skeletal Class I pattern (ANB = 2.8°) with a high mandibular plane (SN-MP = 46.6°, FMA = 34.7°), possibly because of the steep anterior cranial base. The patient is in cervical vertebral maturation stage 5 (Figure 3; Table 1). Puberty had already begun before his first visit to our office, and his peak mandibular growth ended at least one year prior to this stage. His ABO Discrepancy Index score is 27 (Figure 4). 42 Table 1. Initial Lateral and Cephalometric Measurements Variable Norm Pretreatment SNA (°) 82.0 75.4 SNB (°) 80.0 72.6 ANB (°) 2.0 2.8 FMA (FH-MP) (°) 25.0 34.7 SN-MP (°) 32.0 46.6 4.0 8.9 104.0 104.4 4.0 11.1 IMPA (L1-MP) (°) 90.0 96.6 Upper lip E-line (mm) −4.0 2.6 Lower lip E-line (mm) −2.0 6.4 U1-NA (mm) U1-SN (°) L1-NB (mm) PCSO Bulletin Spring 2020