This study investigated the soft tissue profile change of the chin following genioplasty. The subjects were 20 females who underwent genioplasty. They were divided into two groups depending on the directions of surgical displacement of the chin. In 11 patients anterior repositioning was made (forward movement group) and in 9 patients posterior repositioning was made (backward movement group).
For each patient, lateral cephalograms taken preand postoperatively were traced and superimposed, and then linear measurements were obtained.
The results were as follows: 1. There were differences in soft tissue reaction to hard tissue displacement between the forward movement group and backward movement group.
2. In the forward movement group, the size of the chin increased as a result of further forward displacement of soft tissue pogonion in spite of forward displacement of lower labial sulcus. In the backward movement group, the size of the chin decreased as a result of backward displacement of soft tissue pogonion and forward displacement of lower labial sulcus.
3. The horizontal displacement ratio of soft tissue pogonion to pogonion was 148% in the forward movement group, and 33% in the backward movement group.
4. There was a significant positive correlation between the horizontal change of pogonion and soft tissue pogonion, horizontal change of menton and soft tissue menton, horizontal change of pogonion and the size of the chin, and horizontal change of menton and the size of the chin. On the other hand, in the forward movement group, there was no correlation between skeletal changes and soft tissue changes of the chin.

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This study investigated the long-term stability of jaw relations and occlusion following surgical orthodontic treatment cases. Subjects consisted of seventeen adult patients. Eleven patients received sagittal splitting ramus osteotomy, SSRO, of the mandible and six patients received two-jaws surgery, Le Fort I osteotomy, of the maxilla and SSRO of the mandible. They were observed over five years after the end of active treatment (mean: 8 years 5 months), and lateral X-ray cephalograms were taken at the beginning (T1), the end of active treatment (T2) and the latest examination (T3).
The results were as follows between T2 and T3. In the SSRO group, there was no significant difference and that was stable. In the SSRO + LF I group, total face height was increased 1.4mm and upper incisors were lingually inclined and decreased by 3.9 degrees.
The result of the surgical orthodontic treatment was stable and the change of retention phase limited in clinical acceptance. There was no significant difference in postoperative stability between the SSRO group and SSRO + LF I group.

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This study simulated the bone support after maxillary advancement by CT images and evaluated morphological characteristics of maxillary sinus in Le Fort I osteotomy sites. For forty-nine Japanese jaw deformity patients, CT images were taken before orthognathic surgery. In 3mm and 5mm maxillary advancement, the overlap of bone images was examined from the CT images 2mm above the anterior nasal spine of maxilla. The results were as follows: All cases had bony contact at the lateral piriform rim, the base of the zygomatic process of the maxilla and the medial wall of the sinus in 5mm maxillary advancement. Few cases had bony contact at the anterior wall in 3mm. Some cases had it at the posterior wall in 3mm or 5mm. The shape of the posterior wall of the maxillary sinus was subjectively grouped into the following three types: Straight type, S type or J type. In the S and J types, the percentage of bony contact of the posterior wall after maxillary advancement was higher than that in the Straight type.
These findings suggest that the preoperative CT scan along the osteotomy line is clinically useful.

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To shorten the treatment period for maxillary protrusion in adults, we moved the upper anterior alveolar segment posteriorly en bloc by compressive osteogenesis using skeletal anchorage combined with corticotomy.
The operation was performed in two stages. In the first operation corticotomy of the palate bone was performed at the first or second premolar region. In the second operation, corticotomy of the labial side alveolus and fitting of the anchor plate were performed, and with compression beginning about two weeks later. Also, the distal segment was compressed using skeletal anchorage posteriorly, and superiorly.
A 19-year-old female with maxillary protrusion was treated by this method. After retraction started, posterior movement of the anterior segment was observed after about 3 months. The treatment period for the maxilla was about 12 months.
The advantages of this method include, 1) operation under local anesthesia is possible, 2) the blood supply to the bone segment is maintained, 3) the treatment period can be greatly shortened, 4) it is possible to operate in parallel with the orthodontic treatment, 5) the operative method is simple and the invasiveness of surgery is reduced, 6) the possibility of necrosis of pulp is low, and 7) anchor loss of molar can be prevented by using skeletal anchorage.
The demand for orthodontic treatment for adults will likely continue to increase in the future, and surgically assisted orthodontics in adult patients with various restrictions is a useful treatment.

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In cases of severe mandibular prognathism, hypergrowth of the mandible is frequently complicated by maxillary undergrowth. Recently, two-jaw surgery has been performed in such cases, in which gradual advancement of the maxilla by distraction osteogenesis, and then posterior shift of the mandible by sagittal split ramus osteotomy are carried out. To treat mandibular prognathism complicated with maxillary undergrowth, we performed gradual advancement of maxilla by using an internal distraction device, and then carried out sagittal split ramus osteotomy approximately 5 months after.
The patient was an 18-year and 4 month-old male with malocclusion, and was diagnosed as having skeletal class III deformities with maxillary undergrowth and open bite. After preoperative orthodontic treatment, the maxilla was advanced approximately 10mm by distraction osteogenesis. About 5 months after, the mandible was posteriorly shifted by 10mm on the left side, and 12mm on the right side by sagittal split ramus osteotomy.
As a result, the concavity of the middle face and the mandibular prognathism were improved. Good and stable occlusion was obtained. Furthermore, improvement in speech function by this treatment was also confirmed.

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