## 1 Introduction  
One of the goals of orthodontic treatment is to achieve aesthetic harmony between maxillofacial morphology and facial features, whilst also establishing occlusion. Obtaining a beautiful smile line is important [1, 2]. In general, gingival exposure of less than 2 mm with a full smile is considered aesthetically pleasing and youthful [3]. On the other hand, a gummy smile is a condition in which excess gingiva is visible during a full smile. Gummy smiles are thought to be caused by soft tissue odontogenic causes due to the overeruption of maxillary anterior teeth, altered passive eruption, short upper lip, and skeletal causes due to excessive vertical growth of the maxilla [2, 4, 5, 6]. Moreover, gummy smiles are considered an instigation factor for gingivitis in the anterior maxillary region [7, 8], and improvement of the gummy smile from a young age is considered beneficial.  
Conventional methods for improving a gummy smile include the intrusion of incisors, extrusion of posterior teeth using activator, bite ramps, gingivectomy of the maxillary anterior teeth, injection of Botox into the upper lip, retraction of the maxillary anterior teeth, and surgical orthodontic treatment by a combination of LeFort 1 and maxillary horseshoe osteotomy [4, 5, 6]. Treatments are chosen in accordance with the cause. In recent years, a method for improving gummy smiles in adults using an orthodontic anchor screw has been reported [9, 10]. However, the improvement of a gummy smile by surgical orthodontic treatment is usually achieved by combined LeFort 1 and maxillary horseshoe osteotomy, a type of orthognathic surgery, to shorten the facial height [11, 12], which is very invasive. Furthermore, ways to improve a gummy smile using an orthodontic anchor screw are also slightly invasive. In addition, these approaches are used after growth is complete.  
Several treatment methods using orthodontic anchor screws have been reported for gummy smiles during the growth period [13, 14]. [PERSON] et al. treated two Angle Class II division patients with gummy smiles, in the growth period, using orthodontic anchor screws, and reported the correction of excessive vertical growth of the maxillary anterior teeth and the subsequent alleviation of gummy smiles [13; 14]. This suggests that gummy smiles may be improved if the vertical growth of the maxillary anterior teeth is suppressed. However, gummy smile patients, especially those of school age, and their parents, may exhibit resistance to surgical invasion or treatment using orthodontic anchor screws. In addition, patients in the growth period require special attention because permanent tooth germs may be present in the bone, or the roots may be immature. We therefore considered whether it would be possible to suppress the eruption of maxillary anterior teeth with a removable orthodontic appliance without surgical intervention in patients with gummy smiles in their growth period.  
Here, we used SBJA [15] in combination with the high-pull J-hook headgear to suppress the vertical excessive growth of the upper jaw in three class II patients with vertical excessive growth of the upper jaw during the growth period.  
Consent was obtained from patients and their guardians for their inclusion in this report according to Ethical Guidelines for Medical and Health Research Involving Human Subjects in Japan.