In intraoral vertical ramus osteotomy (IVRO), the important issue is how to decide the initial point of the osteotomy to avoid injuring the mandibular nerves. We had developed a simple technique to transfer the initial point of the osteotomy determined by the preoperative panoramic radiograph to the actual ramus. This technique was recently modified. The aim of the present study was to introduce this modified technique and to confirm its better reproducibility.
IVRO using our technique was performed in seven mandibular prognathism cases. A highly experienced surgeon in this technique performed the surgery on the right side, while seven oral surgeons who had had no experience of IVRO performed it on the left side. Positional accuracy of the initial point of osteotomy was compared between the experienced surgeon and the unexperienced surgeons.
The maximum discrepancies between the scheduled and performed osteotomy points were 1.1mm anteriorly, 1.3mm posteriorly for the highly experienced surgeon, and 1.1mm anteriorly, 1.7mm posteriorly for the unexperienced group. The median and interquartile range of the absolute discrepancies were 1.1mm and 0.3mm for the experienced surgeon, and 0.8mm and 0.6mm for the unexperienced group, respectively. No significant differences were found between the two groups. In this series, transient hypesthesia of one side of the lower lip was documented in a case who underwent IVRO with genioplasty. It was not clear whether the hypesthesia was related to IVRO or geni oplasty.
This study shows the efficacy and safety of this modified technique even when performed by less experienced surgeons.

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The purpose of this study was to clarify soft tissue changes of a frontal face in prognathic patients following surgical mandibular retrusion.
Twenty-two adult prognathic patients without facial asymmetry, who underwent sagittal splitting ramus osteotomy using screw fixation, formed the basis of this study. A pair of pre- and postoperative standardized frontal facial photos and lateral cephalograms were used for soft and hard tissue analysis. For quantitative evaluation of the facial photos, the amount of sagittal rotation of the head based on FH head position (0°) was computed using lateral cephalograms and the facial photos presenting less than ±2°of pitching angle of the head were used for the sample as proper frontal facial photos. A paired t test was used to indentify significant hard and soft tissue changes of a frontal face following surgery. A Pearson correlation analysis was used to distinguish soft tissue changes from hard tissue changes.
The results were as follows:
1.Skeletal deformity of the subjects was characterized by remarkable protrusion of the mandible, coupled with lingual tipping of the lower central incisors. Distinguishing mandibular backward movement with a small amount of rotation was found following surgery.
2.Significant changes in the soft tissue were found in the shape and position of the lip. The thickness of the upper red lip significantly increased and the width of mouth aperture significantly decreased. The lip position demonstrated significant downward movement together with significantly increased height from subnasale to stomion and significantly decreased height from stomion to soft tissue menton.
3.The facial width increased significantly at all areas and in particular, the ratio of facial width to lower facial height increased remarkably around the chin and lip areas.
4.A significant correlation was found between the vertical positional change of lip and the sagittal change of the mandible, while no significant correlation was found between the change of lip shape and the sagittal change of the mandible.
These results suggested significant effects of sagittal splitting ramus osteotomy on the change of lip shape and position as well as facial outline, which could remarkably improve the frontal facial appearance following surgery.

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Although several reports have discussed the effect of two-jaw surgery on the nasal tip and upper lip region, few have mentioned changes in the cheek line, and no quantitative analysis of the cheek line was performed.
In this study, the morphological changes of the soft tissue profile (mainly the cheek line) were examined in skeletal Class III patients who had undergone two-jaw surgery. The subjects were 12 skeletal Class III patients (four females and eight males) on whom two-jaw surgery was carried out at Niigata University Dental Hospital. The controls were 12 skeletal Class III patients (eight females and four males) who had undergone mandibular setback only.
Preoperative and postoperative cephalograms were traced, and analyses of hard tissue, soft tissue, and the cheek line were done. On the cheek line, three angular measurements were made:∠C1, ∠C2, and ∠C3, in addition to the anteroposterior movement of the cheek line (C4, C5).∠Cl is the angle made between the cheek line and parallel line with the FH plane at the intermediate point between the FH plane and Pronasale.∠C2 is the angle made between the cheek line and a horizontal line located below Subnasale.∠C3 is the angle made by the lines connecting the intersection points of the cheek line on the parallel line with the FH plane at the intermediate point between the FH plane and Pronasale.
The results were that, in two-jaw surgery patients, changes of Pn and Sn were similar to those of previous studies. The upper part of the cheek line moved in a forward direction and ∠C1 tended to increase, the lower part of the cheek line changed to convex countor and ∠C2 tended to decrease. As a result, the cheek line tended to become more convex in the two-jaw surgery group than in the one-jaw surgery group.
In conclusion, two-jaw surgery was considered to be quite effective for the esthetic correction of skeletal Class III patients, especially those with maxillary deficiency.

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Although mandibular elongation by distraction osteogenesis is an effective procedure for treating hemifacial microsomia, improvement in the facial appearance and malocclusion is frequently difficult due to insufficient maxilla inferior elongation in cases of the distraction only in the mandible. Therefore, simultaneous distraction of the maxilla and mandible has been recently performed, in which distraction devices are placed only in the mandible, and the maxilla and mandible are simultaneously elongated, maintaining the occlusal relationship by intermaxillary fixation. However, there have been no reports of simultaneous maxillary and mandibular distraction osteogenesis, in which distraction devices were placed in both the maxilla and mandible, and bone elongation in the maxilla and mandible was separately performed. In this study, we performed simultaneous maxillary and mandibular distraction after inserting distraction devices in both the maxilla and mandible in a case of hemifacial microsomia.
The patient was a 14-year 4 month-old female, who was referred to our department because of facial asymmetry. The patient was diagnosed as having Murray's classification type II hemifacial microsomia with left hypoplasia in the mandibular ramus, coronoid process, and condylar process, and left hypoplasia of the maxillary bone, and underwent simultaneous maxillary and mandibular distraction 13 months after the preoperative orthodontic treatment.
In the maxilla, high Le Fort I osteotomy was performed, and an alveolar device was placed. In the mandible, corticotomy in the antegonial notch area was performed, and a mandibular distraction device was placed. As a result of simultaneous maxillomandibular bone extension, the left maxillary bone was vertically extended by approximately 10mm, and the mandibular bone was anteriorly extended by approximately 20mm, showing improvement in the occlusal plane inclination and facial asymmetry.

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