The purpose of this study was to compare the dimensional change in the upper airway of prognathic patients who underwent either sagittal split ramus osteotomy (SSRO) surgery only or a combination of Le Fort I osteotomy and SSRO surgery. The sample consisted of 65 patients who were diagnosed as having skeletal mandibular prognathism. They were divided into two groups: 32 patients who underwent mandibular setback surgery using SSRO (SSRO group) and 33 patients who underwent two-jaw surgery (i.e., Le Fort I osteotomy plus SSRO; two-jaw group). To compare the jaw relationship, the position of the hyoid bone and upper-airway dimensions using sets of three lateral cephalometric radiographs that were taken before surgery (T0), at three months after surgery (T1) and two or more years after surgery (T2) were examined in each group. As a result, the middle and inferior upper-airway dimensions became narrower after surgery and the middle upper-airway dimensions recovered after a few years in the SSRO group and two-jaw group. In the SSRO group, a significant positive correlation was found between the amount of mandibular set-back and the middle or inferior upper airway from T0 to T1, and T0 to T2. In the two-jaw group, a significant positive correlation was found between the amount of mandibular set-back and the middle or inferior upper airway only from T0 to T1. In both groups, the position of the hyoid bone was changed to the infero-posterior position from T0 to T1. After that, the hyoid bone in the SSRO group changed to a more superior position. However, the result was different in the two-jaw group because the position of the hyoid bone returned to the same position as before surgery. In conclusion, when orthognathic surgery is performed, it is suggested that the surgical method influences the upper-airway dimension between those patients treated with only SSRO and those with two-jaw surgery.

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[Purpose] We have developed a system for integrating three-dimensional facial and dental data obtained by optical laser scanner. The purpose of this study was to three-dimensionally analyze changes in soft tissue with those in hard tissue after mandibular setback surgery by a multiple linear regression analysis, and to improve the accuracy of explaining soft tissue changes.
[Materials and methods] The subjects consisted of 18 skeletal Class III patients, who had been surgically treated by BSSRO at the Department of Oral Surgery, Niigata University Medical and Dental Hospital. Ten subjects had over 3mm midline deviation of the lower dentition compared with the upper one.
Materials included three-dimensional surface data of the face with the anterior teeth, dental casts and lateral cephalograms taken before and after orthognathic surgery. Three-dimensional facial and dental data were integrated according to the method previously reported, and then the coordinate system, measurement regions and measurement items were established.
A multiple linear regression analysis was performed, with the variation of soft tissue as the dependent variable, and the change in hard tissue, variation of soft tissue thickness, soft tissue thickness before orthognathic surgery, overjet, and midline deviation in each area as explanatory variables, by the stepwise method (y = b₁x₁ + b₂x₂ + ··· + b_ix_i + c, p = 0.2). Adjusted R-squares were worked out as an index of the regression equation.
[Results] Obtained values of adjusted R-squares were 0.716-0.862 in the lower buccal region of the deviation side, lower lip region and chin region, and 0.284-0.687 in the upper buccal region of the deviation side, subnasal region, upper lip region, upper buccal region and lower buccal region of the non-deviation side. Although the latter values were less than 0.7, they were better than the values obtained by a simple linear regression analysis in our previous study.
[Conclusions] The results suggest that multiple linear regression analysis can be used to precisely explain soft tissue changes after mandibular setback surgery.

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It is a challenge to attain good stability in patients who have mandibular prognathism with open bite for a long time after surgical orthodontic treatment. In this study, we analyzed the cephalometric changes after sagittal split ramus osteotomy (SSRO) in mandibular prognathism patients with open bite in order to investigate the factors influencing the long-term stability.
Fourteen patients were enrolled in this study. All the patients were diagnosed as mandibular prognathism with open bite and underwent SSRO at Tokyo Medical and Dental University Dental Hospital, and were followed up for more than 10 years. Overbite (OB) was used as a parameter for the stability of occlusion. OBs were evaluated at two stages, i.e., at the beginning of retention and more than 10 years after surgery. The samples were divided into two groups: Unstable (U) group (8 cases) in which OB decreased by 1mm or more, and Stable (S) group (6 cases) in which OB decreased by less than 1mm. Dento-facial changes were analyzed by lateral cephalograms at 3 stages (T1: first visit, T2: beginning of retention, T3: more than 10 years after surgery) and cephalometric measurements were performed to compare the two groups.
The following results were obtained:
1. At T3, OB of the U group was significantly less than that of the S group. No significant difference was observed in overjet at all stages. OB of the U group significantly decreased during retention.
2. Significant differences were found in the amounts of setback between the two groups.
3. L1 to MP significantly increased during active treatment but it decreased during the retention period in the U group. Mandibular plane angle (MP) significantly increased during active treatment and retention in the U group.
4. A negative correlation was found between the changes of L1 to MP and OB during active treatment and retention in the U group.
From our data, unstable samples that showed an increase of MP and a decrease of L1-MP as a result of SSRO for mandibular prognathism with open bite tend to exhibit a reduction of OB along with labial tipping of the lower incisors during long-term follow-up. It is therefore suggested that excessive lingual tipping of lower incisors should be avoided during active treatment by considering the balance of soft tissues, such as the tongue and lip, for the long-term stability.

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This retrospective study analyzed the treatment of jaw deformities in 651 cases who underwent surgical orthodontic treatment at the Showa University from 2002 to 2011.
Our analysis found: More females (n = 402) than males (n = 249) were treated, with a male: female ratio of 1:1.6.
The mean age of all patients (n = 651) at time of surgery was 26.6 years, and this mean has tended to increase in recent years.
The most common presenting conditions were mandibular prognathism without other deformities of the jaw (64.1%), mandibular prognathism with asymmetry (18.9%), and maxillary protrusion (6.1%).
Cases of maxillary protrusion, mandibular prognathism with open bite, and mandibular prognathism with asymmetry have increased in recent years.
A combination of Le Fort I and horseshoe osteotomies were performed for two-jaw surgeries from 2008, and three-segment maxillary osteotomies were performed for arch reductions from 2009. These procedures tended to increase.
The improvement in surgical orthodontic treatment and diagnostic imaging seems to have resulted in a diversification of operative procedures.

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The committee which is drawing up guidelines for the treatment of jaw deformities in the Japanese Society for Jaw Deformities carried out an investigation of patients with jaw deformities. The purpose of the present investigation was to collect and analyze the patient questions (PQs) for the treatment of jaw deformities from these patients.
We collected 316 answers from 136 patients (54 males and 82 females) who had visited for treatment one of the medical and/or dental institutions to which committee members belonged. According to the classification of PQs, the duration and timing of treatment was the most common question (23.1%), followed by postoperative course (19.6%), treatment methods (19.3%), complications or postoperative symptoms (12.7%), anticipated efficacy (9.8%), treatment policy (5.1%), cost of treatment (3.2%), pathogenesis (1.6%) and others (4.4%). PQs were collected systematically and ranged widely.
In the next step, this committee will select clinical questions based on these PQs and create a draft version of the clinical guideline for the treatment of jaw deformities by the GRADE system.

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The development of velopharyngeal incompetence in patients who have previously received surgery of maxillary advancement has been reported. Here, we report a case of unilateral cleft lip and palate with mild preoperative velopharyngeal incompetence.
The case was a 20-year-old male patient, referred to our clinic with a chief complaint of maxillary retrusion. We confirmed the diagnosis of maxillary retrusion and mandibular prognathism. The patient underwent bilateral sagittal splitting ramus osteotomy and maxillary advancement by distraction osteogenesis with a rigid external distraction device. The velopharyngeal function was evaluated using perceptual speech assessment, nasoendoscopy, and cephalometric analysis. Although the maxillary advancement was larger than 10 millimeters in this case, the patient's velopharyngeal function remained without deterioration after the maxillary distraction.

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