This study investigated the relation between personality characteristics and types of jaw deformities and evaluated the influence of orthognathic surgery on personality characteristics.
The subjects consisted of 52 patients (16 males and 36 females) in whom jaw deformities were surgically corrected and the mean age at surgery was 26.3 years. They were divided into four groups based on the types of jaw deformities such as mandibular protrusion with or without maxillary retrusion, mandibular retrusion with or without maxillary protrusion, open bite and asymmetry.Personality characteristics were analyzed using Minnesota Multiple Personality Inventory (MMPI) and Rosenberg's Self-Esteem Scale before and six months after surgery, and the Kruskal Wallis test and t-test were used for statistical analyses.
Preoperative MMPI scores were not significantly different from normal values of their generation as a whole, but the distribution of Depression Scale and Self-Esteem Scale scores among the four groups were significantly different. The Depression Scale score in the asymmetry group was higher than those in the other groups and the Self-Esteem Scale score in the asymmetry group was lower than those in the other groups. After surgery, the Depression Score decreased in the asymmetry group and the Self-Esteem Scale score increased in all groups except the open bite group.
In conclusion, it is considered that patients with asymmetry are likely to have an inferiority complex and orthognathic surgery for such patients has a favorable effect on personality characteristics because the deformity and the change of full-face appearance are easily recognized by themselves.

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This study was designed to evaluate the morphological changes of the frontal facial soft tissue in prognathic patients with mandibular deviation who had undergone One-jaw or Two-jaw surgery. The subjects were divided into two groups: Group 1 (Two-jaw group) consisted of 18 skeletal Class M female patients who had undergone Le Fort I osteotomy and Sagittal Splitting Ramus Osteotomy (SSRO). Group 2 (One-jaw group) comprised 18 skeletal Class HI female patients treated by only SSRO.
A pair of pre-and post-operative standardized frontal facial photos were used for soft tissue analysis.
The angular and linear measurements of the nose, lip, and lower facial lines were studied on the standardized frontal facial photos.
The results obtained were as follows:
1. The quantity of postoperative Me deviation significantly decreased in the Two-jaw surgery group.
2. No change in the nose width was observed in the One-jaw surgery group, while the nose width was significantly increased after surgery in the Two-jaw surgery group. Asymmetric nose width before surgery changed to the symmetric one after surgery in the Two-jaw surgery group.
3. Lip width was significantly increased in the Twojaw group after surgery. The difference in the lip width between deviated and non-deviation sides was decreased in both groups after surgery. Asymmetric lip width before surgery improved in both groups after surgery.
4. The lip line and the lower facial line improved to a more suitable inclination after surgery in both groups.

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A detailed functional and morphological evaluation of the pharynx, especially its relationship with the mandible, is essential for the surgical orthodontic treatment and diagnosis of sleep apnea syndrome. The present study assessed the correlation between pharyngeal and mandibular morphology in 45 adult Japanese women (average age, 27.9 years). Nine measurements in the pharynx, hyoid bone, and epiglottis were analyzed by conebeam computed tomography (CBCT), and six parameters of mandibular morphology were analyzed using lateral cephalograms. A positive correlation was found between pharyngeal space volume and gonial angle, and between pharyngeal vertical length and the mandibular plane. In addition, the results suggested that both antero-posterior position of the hyoid bone and epiglottis width are related to mandibular size. This study suggested that CBCT is a useful tool for three-dimensional evaluation of the pharynx. The results provide clinically valuable information for the diagnosis and treatment of surgical orthodontics, and enhance our understanding of sleep apnea syndrome.

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It is known that excessive strain and strength of the perioral musculature greatly affect dentition and the alveolar process. I devised a lip pressure gauge capable of separately measuring upper and lower lip pressure, and then measured lip pressure in 507 subjects with normal occlusion (244 males and 263 females, aged 7 to 18 years) after confirming the reproducibility of measurement. As a result, (1) lower lip pressure was significantly stronger than upper lip pressure;(2) lip pressure in males was significantly stronger than in females;(3) both upper and lower lip pressures increased with age;(4) the ratio of upper and lower lip pressures was approximately 1: 1.2 to 1.3.

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We reviewed 16 two-jaw surgery cases among 112 cases of orthognathic surgery and patients diagnosed as having jaw deformity between October 1998 and May 2007 at the Department of Oral and Maxillofacial Surgery, Kumamoto University Hospital. The 112 patients who underwent orthognathic surgery showed a male: female ratio of 1: 2.0, the average age at surgery was 22.9 years old, and various surgical procedures were performed.
The 16 patients who underwent two-jaw surgery consisted of 4 males and 12 females and the average age at surgery was 25.1 years old. Ten of the 16 patients were diagnosed as mandibular prognathism with mandibular asymmetry. All patients who underwent two-jaw surgery were treated by Le Fort I osteotomy and sagittal split ramus osteotomy with positioning of the proximal segment by a repositioning system. All the patients underwent fixation with mini-plates on the maxilla, and titanium screws into the mandible. The average surgical duration in these 16 patients was 395 minutes, and the average amount of blood loss was 924g. In 9 of the 16 patients, surgery was performed under hypotensive anesthesia. All patients also received autologous blood transfusion and the average amount transfused was about 760ml.

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Bilateral sagittal split ramus osteotomy (SSRO) is commonly used to treat jaw deformities. The purpose of this study was to evaluate the postoperative course of patients that underwent SSRO from before operation to fiveyearsafteroperation.
A total of 41 female patients with jaw deformities underwent SSRO and their masticatory functions and neurosensory recovery were examined with appropriate indicators pre-and posto-peratively. The control group consisted of 24 females with individual normal occlusion assessed as having normal masticatory function.
The skeletal stability was well maintained for five years after the operation.
The result was that masticatory function following orthognathic surgery showed a decline at one month after surgery, but gradually improved. Especially, the values of occlusal contact area and occlusal force reached the maximum level at four years after surgery. There were no significant differences between the levels of the patients and control subjects three to five years after surgery. The score of the Helkimo index for temporomandibular dysfunctions at one year after surgery was lower than that before surgery. However, this score increased from three years after surgery.
The S-W sensory test was used for clinical sensory testing of the lower labiomental area, and differences in degree of sensory disturbance were statistically analyzed. Most patients experienced a marked sensory disturbance in the immediate postoperative period. These symptoms dramatically improved within one year after surgery. However, the result showed that recovery of sensation tended to be limited to within one year after surgery.

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A late foreign body reaction to a bioabsorbable poly-Llactic acid (PLLA) plate for use in orthognathic surgery is reported.
A 26-year-old female was referred to our hospital in 2001 because of mandibular prognathism. Sagittal split ramus osteotomy was carried out with the use of PLLA mini-plates and screws. The postoperative course was unremarkable, and bone healing was satisfactory. In 2003, 19 months after the operation, the patient had a swelling in the right cheek region. There was no discharge of pus. Curettage was immediately performed, and some fragments of the PLLA mini-plates and screws were removed. We diagnosed this case as a late foreign body reaction to a bioabsorbable mini-plate.

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