The 18th Annual Meeting of the Society for Jaw Deformities was held in 2008, and the 4th education workshop, which included a lecture and training on cephalometric prediction, was held at the same time. To analyze the degree of satisfaction with the contents of the workshop, a questionnaire survey was conducted. Participants were requested to complete a questionnaire and a free-response section which allowed participants to freely express their opinions about the program.
The degree of satisfaction with the workshop, discussion and training was higher than that for the lecture. As for the training programs, the participants requested not only basic contents but also more advanced contents. Both expert participants and young participants attended the workshop, so it was considered that the training programs should be designed to suit the experience of the participants to create more practical and popular workshops.
Future training programs should be divided into a basic course and an advanced course, which should be conducted concurrently by the same staff in separate places. This would enable more efficient educational results to be obtained with limited time, funds and staff available.

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The objective of this study was to visually classify soft tissue profile patterns of patients with skeletal mandibular prognathism using self-organizing maps (SOM).
The subjects of this retrospective study were 90 Japanese adult females (mean age: 22.6±4.2 years) who underwent surgical orthodontic treatment for skeletal mandibular prognathism. The control subjects were 27 Japanese adult females (mean age: 23.8±4.4 years) who underwent non-surgical orthodontic treatment. Pre-treatment cephalograms for the 90 mandibular prognathism and post-treatment cephalograms for the control subjects were traced, and 48 points of measurement were digitalized. Among the 48 points, 27 soft tissue points were used as input data for the SOM with multiple calculation units. The unit groups performed automatic learning of the input data by means of a self-organizing algorithm, and virtual profiles were obtained for each unit. As a result, four soft tissue profile patterns were visualized, and close relationships to the skeletal and dental characteristics were found in each pattern. The most typical soft tissue pattern in Japanese mandibular prognathism seems to be a pattern showing a moderately retrusive maxilla and a moderately protrusive mandible with the lower lip protrusion and the small nasolabial angle.

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The aim of this study was to investigate the relationship among objective and subjective evaluations of facial asymmetry and the results of eye tracking analysis in order to clarify what part of the face medical professionals examine when judging symmetry.
Evaluation was conducted on the preoperative full-face photographs of 30 patients (7 men, 23 women) examined at the Niigata University Medical and Dental Hospital and diagnosed with jaw deformity between June 2002 and May 2008. Evaluators (n=10), comprising 7 oral surgeons and 3 orthodontists, were asked to view a full-face photograph of each patient displayed on a monitor for 20 seconds and to subjectively evaluate and classify them as either 0, ‘almost symmetry’; 1, ‘asymmetry observed, but within permissible limits’; or 2, ‘obvious asymmetry observed requiring treatment.’ Points of gaze were analyzed using an eye-tracking method from the trajectory of the evaluators’ gaze movements during evaluation. We calculated the initial gaze point among the features and gaze time with regard to the eyes, nose, mouth, chin and cheek.
The subjective degree of facial asymmetry was calculated for each patient as the mean evaluation score of the 10 evaluators. Upon comparison with the results of objective photographic analysis, correlations were observed for the degree of deviation of the mental region and oral fissure inclination, angular asymmetry ratio of the mandibular angle, angular asymmetry ratio of the mouth commissure and distance asymmetry of the mandibular angle. Gaze point analysis revealed that the initial gaze point was most often the nose, followed by the lip region. Longest gaze times were observed for the mental region followed by the nose then the lip area; gaze area was focused from the mid to the lower face.
In conclusion, it is suggested that the degree of deviation of the mental region and lip inclination have a large effect on the subjective evaluation of full facial asymmetry.

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Aim: The purpose of this study was to examine the precision of integrating three-dimensional facial and dental data.
Materials and methods: The subject was a 27-year-old male with normal occlusion. Materials consisted of two kinds of facial three-dimensional data: three-dimensional dental cast data and the lateral cephalogram. To confirm the precision of data obtained, measurements were performed three times on different days. Integration of the soft tissue and dental cast data was achieved by using markers. The reference plane was defined with bilateral ear-rods and the left orbital on the soft tissue. The Y axis was the perpendicular line dropped from sella converted from the cephalogram to the reference plane. For analysis of the hard tissue and the soft tissue, cross sections were set up parallel to the reference plane at 2 mm intervals. Radial patterns from the Y axis on each cross section to the hard tissue and the soft tissue were set at 1 degree intervals, and the hard tissue and soft tissue measured values were defined as the distance from the Y axis to the hard and soft tissues, respectively. The mean and standard deviation of the distances among two facial data at gingival exposure and closed lips, and dental cast data in the common region were used to evaluate the precision of the integration. Reproducibility was investigated from the mean and standard deviation of the measured values for the hard tissue and the soft tissue at the same angle of the same cross section.
Results: The mean and standard deviation of the distances between two facial data were 0.15 mm and 0.01 mm, and those of the distances between facial data at gingival exposure and dental cast data were 0.37 mm and 0.01 mm. With respect to reproducibility of the integrated three-dimensional data, no significant differences were found in the measured values for the hard tissue and the soft tissue for the same three randomly selected points.
Conclusion: The present system is valid for precisely analyzing three-dimensional changes in soft tissue without computerized tomography.

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In this report, we describe the case of a 22-year-old male with severe skeletal Class III who was treated with distraction osteogenesis of the maxilla and intraoral vertical ramus osteotomy (IVRO). The severe skeletal Class III was accompanied by hypoplasia of the maxilla and overgrowth of the mandible (overjet, -20.0 mm; overbite, 1.0 mm). A high Le Fort I osteotomy was carried out, and the maxilla was distracted using the rigid external distraction II (RED II) system. After the active distraction and consolidation period, rigid fixation of the maxilla and IVRO were carried out; splitting of the mandible midline was added to the procedure to achieve a narrow mandibular arch width. After 6 months of postoperative orthodontic treatment, the occlusion and masticatory function of the patient had improved, and he was satisfied with the outcome of the treatment.

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The patient was a 19-year-old male with mandibular prognathism, open bite and a thin symphysis. The chief complaints were difficulty in biting with the anterior teeth and anterior crowding. The problems were: 1) mandibular prognathism; 2) skeletal open bite; 3) a narrow upper dental arch; 4) severe lingual inclination of the lower incisors and a thin symphysis; and 5) crowding.
Surgical procedures were utilized to perform orthodontic treatment. Before the orthognathic surgery, crowding and the narrow dental arch were eliminated with orthodontic treatment involving surgically assisted rapid palatal expansion. Segmental osteotomy and gradual distraction osteogenesis of the lower anterior teeth were performed to change the severe lingual inclination of the symphysis. After alignment of the upper and lower dental arches, sagittal split ramus osteotomies were undergone to correct the mandibular prognathism and skeletal open bite. In the post-operative period, detailing and completing teeth alignment were performed, and suitable occlusion was finally achieved. This case shows that changing the inclination of the symphysis by distraction osteogenesis is effective for patients with a thin symphysis.

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