The purpose of this study was to evaluate postoperative changes of the frontal facial soft and hard tissues and to clarify the limit of treatment in patients with facial asymmetry who had undergone only sagittal splitting ramus osteotomy.
Method: The subjects were 21 adult jaw deformity patients with facial asymmetry, and a pair of pretreatment and postoperative (more than 6 months after operation) standardized frontal facial photos and postero-anterior cephalograms were used to evaluate the improvement of facial symmetry. For quantitative evaluation of the facial photos, the patient's FH plane and the plane of the floor were set up in parallel, and the head was fixed firmly by a ear rod. We measured the soft tissue Menton deviation angle and distance, the lip tilt angle and the facial mandibular plane tilt angle on the standardized frontal facial photos. Next, we measured the hard tissue Menton deviation angle, the occlusal plane tilt angle and the mandibular plane tilt angle on the postero-anterior cephalograms. Hard and soft tissue changes were statistically evaluated.
Result: The soft tissue Menton deviation angle (4.4 ± 1.2°) and distance (9.1 ± 2.8mm) significantly decreased (2.0 ± 1.7° and 4.2 ± 3.4mm) after operation. The lip tilt angle (3.8 ± 2.3°) and the facial mandibular plane tilt angle (2.7 ± 3.1°) also significantly decreased (1.9 ± 1.9° and 1.4 ± 2.9°) after operation. Hard tissue Menton deviation angle (4.5 ± 1.8°) significantly decreased (2.6 ± 1.3°) after operation. The occlusal plane tilt angle (2.1 ± 3.3°) and the mandibular plane tilt angle (2.4 ± 3.3°) slightly decreased (2.0 ± 2.9° and 1.4 ± 3.4°) but were not statistically significant. According to regression analysis of the cases whose angle between the soft tissue facial midline and the soft tissue Menton was less than 4.0°, and also whose angle between the hard tissue facial midline and the Menton was less than 3.2°, the soft tissue Menton deviation was improved to a normal range. However, in those cases whose angle exceeded 4.0° and 3.2°, the soft tissue Menton could not be corrected within the normal range. Therefore, in such cases, after thorough examination of maxillary deflection against the skull and the mandibular deformation itself, which cannot be detected by cephalogram, two-jaw surgery, genioplasty and mandibular angle plastic surgery will be necessary.

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With the growth of the aged population, untreated elderly patients who have malocclusion with prognathism will increase. When a patient with prognathism becomes edentulous, we often experience, during treatment, complete dentures not being stable and the patient is not satisfied with the form of the dentures because the relative position of the maxilla and mandible is skeletal Class III. We report a case of mandibular prognathism with edentulous maxilla by orthognathic treatment. The patient is a 58-year-old woman. Her complaint is that because the full maxillary denture is not stable, she cannot bite right and where the mandibular protrusion is. The diagnosis is a mandibular protrusion with edentulous maxilla and partially edentulous mandible (7-4). We made a full maxillary denture and sagittal split ramus osteotomy (SSRO) was performed. After orthognathic surgery, the position of the maxilla and mandible were improved. Thereafter, we made a definitive prosthesis. As the dentures were stable and the mandibular protrusion had improved, the patient was satisfied.

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