Orthognathic treatment for jaw deformity is performed to improve skeletal malocclusion, functional disorders, and the aesthetics of the face from the frontal and lateral aspect. It is important to understand the dentofacial stability of the jaw after surgical orthodontic treatment. In this review, we survey the literature concerning postoperative stability for all types of orthognathic maxillary for jaw deformities. １． The postoperative stability of single-tooth dento-osseous osteotomy and anterior segmental maxillary osteotomy was good, but that of maxillary posterior segmental osteotomy was poor. ２． Following two-jaw surgery (Le Fort Ⅰ osteotomy and sagittal splitting ramus osteotomy or intraoral vertical ramus osteotomy), the anteroposterior position of the upper/lower jaws and the overjet were stable. However, the vertical position of the upper/lower jaws was unstable, the overbite tended to decrease, and it was thought that the vertical stability depended on the patientʼs dentofacial state atthe first examination. ３． Although maxillary bone lengthening by distraction osteogenesis was subject to relapse from 6 months to 1 year after the surgery, it tended to become stable thereafter.

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We report a case of oral hygiene control with a toothbrushing calender as a visual support tool. A 8 year-old boy patient visited our department with chief conplaint of toothache in left lower molar. There were a lot of decayed tooth in his mouth. He had autism spectrum disorder. We performed a comprehensive treatment under general anesthesia. After treatment under general anesthesia, the patient brushed his tooth after every meal, 3 times a day according to toothbrushing calender. In addition, dentures was weared as a space maintainer. It is important the need for cooperation consultation room and home and school to keep oral hygiene.

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Dietary habits in Japan have shown recent changes, such as unbalanced nutrition intake and irregular meals, as well as poor eating posture. However, there are few studies of the effects of eating posture, such as foot position and trunk inclination, on the area of occlusal contact and masticatory ability. In the present study, we examined the correlation of foot position and trunk inclination with occlusal contact area and masticatory ability in adults. 　We measured the occlusal contact area using a T-scan Ⅲ®. For masticatory ability, the number of times chewing gummy jelly and time until swallowing were determined. For the reference sitting position, all subjects were ask to use a posture with the soles of the feet in contact with the ground, while keeping the trunk vertical to the floor surface and a horizontal eye-ear plane. In addition, 3 different types of poor posture were used. The occlusal contact area was examined in relation to the reference sitting position, chewing frequency, and time until swallowing for correlations among the parameters, as well as gender and degree of obesity. Furthermore, occlusal contact area, chewing frequency, and time until swallowing were compared among the 4 posture groups. 　There was no significant difference between genders in regard to occlusal contact area. In contrast, chewing frequency and chewing time until swallowing were significantly lower in males. There were no significant differences in occlusal contact area among the groups related to the degree of obesity. However, chewing frequency and time until swallowing were significantly lower in the obesity group as compared to the standard body weight and low body weight groups. A high correlation was observed between chewing frequency and time until swallowing, while no correlation was found between occlusal contact area and chewing frequency or chewing time. As for the influence of posture, the occlusal contact area was significantly decreased, and chewing frequency and time until swallowing were significantly increased when sitting in the 3 different poor posture positions as compared to the reference position. 　On the basis of our findings, it is suggested that chewing frequency and time until swallowing vary by gender and degree of obesity. Furthermore, poor posture has effects on occlusal contact area, as well as on chewing frequency and time until swallowing.

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