## 2 Methods
### Combined Use of SBJA and High-Pull J-Hook Headgear
Treatment approach  
We decided to use the SBJA for the purpose of improving the overbite, and skeletal maxillary prognathism for bite jumping, suppression of maxillary growth, and promotion of mandibular growth. Furthermore, we elected to suppress the vertical growth of the maxillary anterior teeth and to improve the gummy smile by using a combination of SBJA and high-pull J-hook headgear. To improve the narrowed maxillary arch, we planned to expand the maxillae laterally through enlargement of the SBJA expansion screw. The patient was instructed to use the appliance for more than 12 h per day. Treatment course  
The patient used SBJA (with expansion screw) and the high-pull J-hook headgear for 28 months, from 11 years and 5 months to 13 years and 9 months of age. Treatment results  
In this patient, as a result of treatment, SNA remained unchanged from 85.0\({}^{\circ}\), while SNB increased from 78.5\({}^{\circ}\) to 80.5\({}^{\circ}\). As a result, ANB changed from 6.5\({}^{\circ}\) to 4.5\({}^{\circ}\), and the skeletal maxillary prognathism improved. The maxillary anterior teeth (Is-Is\({}^{\circ}\)), which had been high, returned to normal height. With growth, the maxillary molars protruded, but the protruding of the maxillary anterior teeth was suppressed, and the occlusal plane (oclusal plane to FH) changed from 19.0\({}^{\circ}\) to 11.5\({}^{\circ}\), and altered to an anterior elevation (Figure 4, Table 1). Wits appraisal was \(-\)2.0 mm. The left central incisor cervical exposure while smiling decreased from 6.0 mm to 0.0 mm, thus improving the gummy smile (Figure 5A). In addition, the overbite improved, and the molar relationship changed from class II to class I (Figure 5B). No root resorption was observed in the maxillary anterior teeth (Figure 6). Case 2. Findings from initial examination  
The patient was a Japanese boy of 10 years 0 months at the time of his initial examination, with a chief complaint of rattling anterior teeth. In terms of family history, the patient's father had teeth crowding. There was no history of current illness or medical history that was particularly problematic. He had no notable habits. In terms of facial findings (Figure 7A), the frontal view did not demonstrate any deviation of the mandible. When smiling, the distance between the upper lip to the maxillary left central incisor cervical line was 5.5 mm, and a gummy smile was notable. In the lateral view, a protrusion of the upper and lower lips was observed. Figure 5: Facial photograph and intra-oral photograph of Case 1 at the end of the first stage of treatment; facial photograph and enlarged photograph of the mouth at the end of the first stage of treatment (**A**); intra-oral photograph at the end of the first stage of treatment (**B**). Figure 6: Panoramic radiograph (**A**) and lateral roentgenographic cephalogram (**B**) of Case 1 at the end of the first stage of treatment. In the intra-oral findings (Figure 7B), the occlusal relationship of the molars was Angle Class II on both the left and right sides, and the overjet was +7.0 mm on the right side and +4.0 mm on the left side. In addition, the overbite was +2.0 mm on the right side and +5.5 mm on the left side, exhibiting a deep overbite. The maxillary anterior teeth were crowded, and the maxillary dentition midline was deviated 1.5 mm to the right from the facial midline. The dental age was stage IIIB, and the width of the dental arches was small in both the upper and lower jaws, exhibiting narrowing. The length of the dental arch was normal for both the upper and lower jaws. Furthermore, the dental arches exhibited a parabolic morphology in both the upper and lower jaws. The panoramic radiographs (Figure 8) showed no abnormalities in the number of teeth. In the cephalogram angle measurement (Table 3), the SNA angle was 85.0\({}^{\circ}\), the SNB angle was 77.0\({}^{\circ}\), and the ANB angle was +8.0\({}^{\circ}\) and large, thus exhibiting skeletal class II. The Frankfort-mandibular plane angle (FMA) was 33.5\({}^{\circ}\).