The most frequently used techniques for correcting skeletal Class III deformity are sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO). The purpose of this study was to compare the clinical outcome including skeletal stability after SSRO with semirigid fixation and IVRO. The subjects of this study were 23 patients who underwent SSRO for mandibular setback with semirigid fixation by titanium miniplate and 20 patients who underwent IVRO for mandibular setback without interosseous fixation. The mean period of maxillo-mandibular fixation was 5.1 days in the SSRO group and 7.3 days in the IVRO group. The evaluation items were skeletal changes, operation time, blood loss, sensory disturbance, temporomandibular joint (TMJ) sound and mandibular range of motion (ROM). Compared with the SSRO group, the B-point and pogonion moved significantly posteriorly in the IVRO at more than 6 months after surgery. Operation time, blood loss and occurrence of sensory disturbance were also less than those in the SSRO group. There were no significant differences in TMJ sound and ROM. The results of this study showed that both methods had minimal relapse and no significant difference in comparison by measurement of B-point and pogonion. In conclusion, both methods are effective for correcting skeletal Class III malocclusion, and the surgical method should be selected in consideration of each clinical distinction.

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This study compared dento-facial changes after two-jaw surgery with or without horseshoe osteotomy of the maxilla in mandibular protrusion patients with open bite or long face. Twenty adult patients who underwent orthognathic surgery to correct mandible protrusion were enrolled in this study. The subjects were divided into two groups based on surgical method: 10 who underwent bilateral sagittal split ramus osteotomy for the mandible and combination osteotomy by Le Fort I and horseshoe for the maxilla (HS-TJ group), and 10 who underwent bilateral sagittal split ramus osteotomy for the mandible and Le Fort I osteotomy for the maxilla (TJ group). Lateral cephalograms were used to analyze dento-facial changes at five stages (T0: first visit, T1: before surgery, T2: within 3 months after surgery, T3: beginning of retention, T4: more than 2 years after surgery). Statistical analysis was performed using two-way layout analysis of variance with Tukey correction. We considered p<0.05 to represent statistical significance.
The following results were obtained:
1. At T0, no significant difference in dento-facial patterns was observed between the two groups.
2. From T1 to T2, SNA angle, SNB angle and ANB angle were improved in both groups after surgery. Significant differences were observed in SNA, SNB, ANB and occlusal plane angle. However, significant differences were observed in mandibular plane angle only in the HS-TJ group. In the HS-TJ group significant differences were observed in all linear measurement items except the horizontal distance of U1. In the TJ group, significant differences were observed in all linear measurement items except the vertical distance of U1.
3. From T2 to T3 and from T3 to T4, no significant differences were observed between the two groups in respect of changes in all measurement items.
4. In two-way layout analysis of variance, a significant difference in ANS-Me was observed between the two groups in respect of the method of orthognathic surgery.
In the HS-TJ group, superior repositioning of the maxillary molar without anterior movement of the maxillary incisor, clockwise rotation of the occlusal plane and decrease in the lower facial height were observed. The postoperative stability of the HS-TJ group was found to be satisfactory. It is suggested that a combination osteotomy by Le Fort I and horseshoe for the maxilla is a useful technique for treating mandibular protrusion patients with open bite or long face.

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The present study conducted a statistical survey of 1118 patients with jaw deformity who underwent surgical orthodontic treatment in the Section of Maxillofacial Orthognathics, Department of Orthodontics, Tokyo Medical and Dental University from 1980 to 2009.
The results were as follows:
1. There were 442 male and 676 female patients (ratio 1:1.5).
2. The mean age at operation of all patients was 24.2 years old. The mean age has tended to increase in recent years.
3. The most common condition was mandibular prognathism without other deformities of the jaw, accounting for 47.3% of the patients. Next was mandibular prognathism with asymmetry, accounting for 20.4%, and then mandibular prognathism with open bite, accounting for 14.1%.
4. The most frequently used surgical procedure was sagittal split ramus osteotomy (SSRO), accounting for 64.0%. The combination of Le Fort I osteotomy and SSRO accounted for 21.0%.
5. For bone fixation after SSRO, wire fixation, which used to be the most common method, has been almost completely replaced by screw or mini-plate fixation in recent years.

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Aspiration pneumonia is defined as lung injury caused by the contents of the oral cavity, pharynges, and gaster accidentally entering the airway. It is divided broadly into three categories: chemical injury, aspiration of particulate food matter, and injury by pathogenic bacteria. Aspiration pneumonia during general anesthesia is very rare, occurring in only 0.01-0.03% of cases. The process of lung injury by chemical pneumonitis is divided into two phases: direct chemical injury and secondary inflammation reaction in the lung tissue. In severe cases, excess inflammation reaction in the lung tissue leads to a systemic inflammatory response syndrome and causes acute respiratory distress syndrome. We report a case of aspiration pneumonia of gastric juice occurring upon induction of general anesthesia for orthognathic surgery in a 23-year-old male. Immediate treatment in the intensive care unit resulted in satisfactory progress. We confirmed later that he had an esophageal hiatal hernia. It is important to prevent perioperative complications and consider measures for aspiration pneumonia.

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This case report presents the surgical orthodontic treatment with two-piece maxillary Le Fort I and intraoral vertical ramus osteotomies of the mandible (IVRO). The patient was a 21-year 3-month-old female with the chief complaint of reversed occlusion and temporomandibular joint pain. The patient had mandibular prognathism with an overbite of 3 mm and overjet of −4 mm and Class III canine and molar relationships. Cephalometric analysis showed a skeletal Class III relationship (ANB, −2.5 degrees). The presurgical orthodontic treatment started with a multi-bracket appliance and without premolar extraction. An arch-width discrepancy between the maxilla and mandible was observed in the dentoalveolar region, which was compensated by buccal inclination of the maxillary posterior teeth and lingual inclination of the mandibular posterior teeth. After 20 months of presurgical orthodontic treatment, a 2-jaw surgery including two-piece maxillary Le Fort I and IVRO was performed. The total treatment period was 28 months. A good facial profile and occlusal relationship were obtained. Our results suggested that orthodontic treatment incorporating two-piece maxillary Le Fort I and IVRO might be effective for patients with arch-width discrepancy between the maxilla and mandible.

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This study investigated maxillary stability after maxillary anterior alveolar osteotomy for maxillary protrusion. Bioabsorbable poly-L-lactide (PLLA) mini plates were compared with titanium mini plates. In the study group, 5 patients received titanium mini plates and 4 patients received PLLA mini plates. For all 9 patients, cephalometric analysis was performed preoperatively (T1), immediately after surgery (T2), and at 1 year after surgery (T3). No significant differences between cases with titanium mini plates and those with PLLA mini plates were found in all cephalometric variables. These results suggest that PLLA mini plates may be used safely for clinical stabilization after maxillary anterior alveolar osteotomy.

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A 40-year-old female visited our department in June 2008 with chief complaints of intraoral denudation of the canine root, occlusion anomaly, and mastication disorder. She had a history of mandibular anterior subapical osteotomy and genioplasty by removal of the mandibular margin of the mental region under general anesthesia in another hospital in June 2007. In December 2007, an aperture was found at the osteotomy site and plate fixation was performed in the same hospital in January 2008. However, denudation of the canine root was found in February 2008 with a mastication disorder that had persisted since the initial surgery, which led her to visit to our department.
At her initial visit, denudation of the canine root was confirmed. The right molars were missing and no contact was found in the anterior teeth. Skin mobility in the mental region was limited, indicating oral food intake without mastication. The patient was diagnosed as fissure fracture of the mandibular bone at the distal region of the lower left canine and faulty union of the alveolar osteotomy site.
Alveolar osteotomy was repeated and the mandibular fracture was fixed under general anesthesia in September 2008. The cortical bone of the former alveolar osteotomy site showed faulty union. Following repeated osteotomy, the dentures were reconstructed by supporting them with preoperatively prepared plate splints and wire splints to check the occlusion, and then the osteotomy site was fixed with a miniplate. Iliac bone was grafted in the bone gap, and intermaxillary anchorage was retained for 20 days postoperatively. Following treatment, the occlusion in the anterior teeth improved and the patient was able to take regular food. However, continuous follow-up is necessary because of persistent partial denudation of the canine root and denudation of the grafted bone.
In the diagnosis and treatment of jaw deformities to correct occlusion and masticatory functions, we consider that preoperative and postoperative occlusal management is important, especially when it appears to be difficult to obtain stability of postoperative occlusion.

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The residual wide alveolar cleft often causes potential risk in bone grafting and prosthodontic treatment for cleft lip and palate patients. While performing cleft reduction, maxillary advancement is required because closure of the cleft space itself with orthodontic/orthognathic treatment will result in a crossbite. In this paper, we report the case of a 21-year 4-month old male with left cleft lip and palate. The patient had undergone orthodontic treatment once at another institute, and he visited our Orthodontic Clinic at the University Hospital of Dentistry, Tokyo Medical and Dental University with a chief complaint of residual cleft space. Overjet and overbite were both 2.0 mm and the intercuspation of the buccal segments was optimal. However, the residual cleft space was 14.5 mm with no history of bone grafting. The right maxillary lateral incisor lacked congenitally, and the left lateral incisor was a lingually malpositioned conical tooth. The midline of the maxillary had right deviation of 6.5 mm. A multibracket appliance was used for the presurgical orthodontic treatment and a Le Fort I osteotomy was performed when the patient was 22-years and 4-months old. During the operation, the left maxillary lateral incisor in the cleft area was extracted. A Twin-Track device was placed along with the maxillary dental arch to guide the surgical movement of the alveolar segments into place. After complete cleft closure was achieved along this splint, maxillary segments were fixed using mini-plates and bone grafting was simultaneously performed. After 2 years of post-surgical orthodontic treatment, acceptable occlusion was achieved and no further prosthetic treatment was required.

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