It is considered that the morphology of the cervicomental region is important when the therapeutic target is established in patients with dento-facial deformity. In the present study, the lateral aspect of soft tissue in this portion was examined in adult Japanese females with normal occlusion and compared with those in patients after orthognathic surgery. As a result, the mean lip-chin-throat angle in patients after orthognathic surgery was 105.7±9.9°, which was smaller than the value of 113.0±5.9° in the subjects with normal occlusion. The mean cervicomental angle in the patient group was 119.1±13.5° which resembled the value of 116.7±8.6° in the normal group. The mean throat length of 33.7±3.6mm in the former was similar to the value of 33.4±3.1mm in the latter group. However, it was suggested that with the aid of an operative method using SSRO alone, complete removal of protruded appearance in the mental region is hardly attainable. In patients who strongly desire improvement in this area, a method to correct this protruded appearance was considered necessary.

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The purpose of this study was to clarify the difference of the mandibular movement between the normal occlusion and the skeletal mandibular protrusion.
The sagittal inclination of condyle paths and the horizontal inclination of condyle paths were examined.
The results were as follows:
1. The sagittal inclination of condyle paths of the normal occlusion was statistically larger than that of the mandibular protrusion.
2. The sagittal inclination of condyle paths of the normal occlusion in anterior movement had a close correlaretion to that in mastication, but the mandibular protrusion had no relation thereto.
3. The horizontal inclination of condyle paths of the normal occlusion in lateral movement was 12.3±2.7° and that of the mandibular protrusion was 13.0±9.6°.
4. The horizontal inclination of condyle paths of the normal occlusion in mastication was distinctly smaller than that in lateral movement, but the mandibular protrusion had no relation thereto.

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Recently, intraoral vertical ramus osteotomy (IVRO) has been applied to patients with jaw deformities as a method for orthognathic surgery in many institutes.
This procedure is relatively easy because the use of special instruments is not necessary and few cases show sensory disturbance in the mental region due to surgical damage of the inferior alveolar nerve. However, the postoperative stability of this method remains unclear. Therefore, to clarify the skeletal (point B) and dental (axis and extrusion) stability of this procedure, the postoperative follow-up data of 12 cases that were treated with IVRO bilaterally were retrospectively investigated.
Point B of the mandible on lateral cephalograms was measured in each case preoperatively, immediately after maxillomandibular fixation (MMF), at MMF removal, and 3 months, 6 months, and 1 year after the operation. In addition, the changes in the upper and lower medial incisors were simultaneously analyzed concerning their axes and extrusion by lateral cephalography and their postoperative occlusal findings were also evaluated.
The results were as follows:
1) The position of point B was remarkably changed posteriorly and inferiorly at MMF removal, and this position was maintained at all follow-up examinations.
2) There were three cases that showed open bite at MMF removal. These cases could obtain good occlusions through postoperative orthodontic treatment.
In conclusion, the results suggested the necessity of skeletal maxillomandibular fixation for good occlusal stability.

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The purpose of this study was to clarify the longterm dentofacial changes after sagittal splitting osteotomies in skeletal Class III patients.
The lateral cephalograms of 7 females observed for more than fifteen years after surgery were used. The postoperative changes in the position of Pogonion were measured.
The results were as follows:
1) From five years to fifteen years after surgery, Pogonion moved antero-posteriolly and vertically. However, five patients who had stable occlusion revealed less displacement.
2) Pogonion of two patients showing some relapse occlusion-wise moved more backwardly and downwardly from two years postoperatively to more than five years postoperatively. Some continuous positional changes of Pogonion was observed even fifteen years after surgery.
The less Pogonion displacement was, the more stable the occlusion was. However, when greater Pogonion displacement is observed, the patient should be given more careful postoperative management.

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Superior repositioning of the maxilla is required in cases with long face and/or open bite. In this paper, clinical evaluations of superior repositioning of the maxilla at Hamamatsu University Hospital are reported.
Patients and methods: Osteotomy was carried out in 277 cases over a period of 21 years. In those cases, superior repositioning was performed in 4 cases (3 females, 1 male). These cases were evaluated in terms of the amount and direction of the maxillary movement, and incidence of the relapse.
Results: In the four cases with open bite, the molar region was planned to be moved superiorly at 3-5mm, and the anterior region at 7--2mm. Le Fort I osteotomy was performed in all cases and the fragments were fixed with miniplates. During the operation, the major palatal artery was not damaged and partial necrosis was not observed in any case. The inferior concha did not interfere with superior repositioning. Postoperatively, no nasal symptoms were observed. The movement of the maxilla was evaluated as the movements of PNS or ANS. In the four cases, cases 1 and 2 showed superior repositioning almost as expected, but cases 3 and 4 showed no superior repositioning and a slight relapse.

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Orthognathic surgery for skeletal open bite is considered to be one of the operations which easily causes relapse. A case of recurrent open bite 12 years after sagittal splitting osteotomy for prognathic and skeletal open bite is presented. The patient was a seventeen-year-old female who underwent sagittal splitting osteotomy after preoperative orthodontic treatment for 1 year 10 months. After that, the follow-up was strictly performed for 3 years, while monitoring the tongue habit, the location of temporomandibular joints, and dental reconstruction. However, she stopped visiting our clinic, and 9 years later she revisited our clinic with a complaint of openbite. During this period, various prosthodontic treatments had been performed by another dentist and the maxillary and mandibular dental arches had changed. She had undergone orthodontic treatment for recurrent open bite for 3 months and open bite had been alleviated.
From the experience of this case, it was suggested that a team-approach, including the postoperative treatment by an oral surgeon, orthodontist, and prosthodontist, is needed during therapy for skeletal open bite.

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In this paper, a mandibular prognathism with posterior disc displacement in TMJ performed intraoral vertical ramus osteotomy (IVRO) was reported. The patient was an 18-year-old female with the chief complaint of difficulty in mouth closing. Posterior disc displacement in left TMJ and anterior disc displacement in right TMJ were found by MRI examination. Although splint therapy and arthrocente-sis in left TMJ were performed, the symptoms did not change. This patient underwent IVRO after preoperative orthodontic treatment. After sugery, bilateral disc position and the symptoms of difficulty in mouth opening and TMJ pain were improved.

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This article is on a case of unilateral Le Fort I corticotomy of a female patient (18 years old). She had a maxillo-facial deformity, accompanied by an asymmetrical unilateral narrow alveolar arch. Her skeletal pattern showed mandibular prognathism. The distances between the mid-palatal line and the first premolar, as well as the first molar, were shorter on the right side of the arch than on the left side by 4mm and 5mm respectively. Her mandible was shifted to the left side from the facial midline by 6mm.
A two-stage surgical operation was performed on this patient. The treatment procedures were 1) to set the rapid expansion appliance, to perform unilateral Le Fort I type corticotomy only on the right buccal side, and to perform preoperative orthodontic treatment without tooth extraction; 2) to carry out the sagittal splitting ramus osteotomy (SSRO) and postoperative orthodontic treatment.
The results showed that the length of total maxillary expansion was greater on the right operated side than on the left side by 2 to 3mm. Moreover, after SSRO, the asymmetry of her frontal view was completely corrected, and a balanced, harmonized profile was obtained.

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A case of mandibular asymmetry of a 19-year-old male is reported. The unilateral sagittal ramus osteotomy combined with contralateral intraoral vertical ramus osteotomy was performed on this case. Although the occlusion and the jaw movement were seemingly improved at the end of active orthogna-thic treatment, new symptoms of temporomandibular joint were observed during the retention period, which required further follow-up.

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This paper describes a patient with microgenia and open bite who was treated by mandibular ramus distraction osteogenesis using an intraoral device.
The patient was a 21-year-old male. An osteotomy was performed in the mandibular ramus region according to Obwegeser's original method (1955).
The mandible was fixed for 4 days to permit callus formation. The mandible was then serially lengthened 0.8mm per day for 20 days, and the mandiblewas lengthened approximately 16mm in total.
Occlusion improved, and after 6 months of consolidation, the intraoral device was removed. Bone union was confirmed in X-ray examination. No marked changes in occlusion have been found after 11 months of follow-up by clinical and radiographic observation.

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A case of osteopathia striata with mandibular prognathism treated by orthognatic surgery is reported. The patient was 17-year-old male with the complaint of mandibular prognathism. In preoperative radiological examinations, sclerosis of the skull and mandible with wave-like striations were found. From the radiographs of the knee, striated pattern of the metaphysis of the long bones parallel to their long axis was found and a diagnosis of osteopathia striata was made. Bilateral sagittal split ramus osteotomy was carried out at the age of 21 years 1 month, however, bone cutting and segmentationwere very difficult owing to the thick cortical bone of more than 10mm at the thickest portion. Partial osteonecrosis was found in the anterior portion of the left side proximal bone segment in the subsequent surgery to remove the fixation screws performed after four months. This seemed to be caused by insufficient blood supply and heat generation while cutting the bone. Fifteen months after surgery, the postoperative course was uneventful and no sign of skeletal relapse had been found.

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A case of maxillary excess is rare in our country. In this case, it is necessary for upper jaw to be moved enough backward movement for obtained satisfactry esthetic result. However, it is difficult to aquire enough backward movement for improvement of functional and esthetic obstruction.
In our case, maxillary excess with labioversion for improvement of functional and esthetic obstruction, it was necessary for to move the upper jaw backward 23mm. However, it was impossible to improve an esthetic obstruction by a surgical method, Le Fort Iosteotomy or alveoler segmental osteotomy.
Therefore, it was necessary to devise a preoperative orthodontic treatment.
Upper first molars were extracted before preoperative orthodontic treatment, and so it was possible to improve functional and esthetic obstruction by simple surgical method, followed by anterior alveolar segmental osteotomy for maxilla.

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For surgical correction of masseteric muscle hypertrophy, Obwegeser-Beckers method, removal of the exostoses at the mandibular angle, is usually performed. However, it is difficult to obtain satisfactory esthetic results by this conventional method. In this paper, a new surgical technique to easily obtain good esthetic results is reported. This technique can remove exostosis at the mandibular ramus without damage to the inferior alveolar neurovascular bundle and surrounding tissue.
The method is as follows:
1. A Lindemann bar is used to cut through the exterior cortical plate of the ramus and the area of the antegonial notch. Then, a bone saw is used to cut through the cortical plate on an oblique line.
2. A splitting chisel is directed and driven inward to the osteotomy line. The exterior cortical plate of the mandibular ramus is removed, and so, this portion has thin, facial esthetics which are improvable.

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