Since distraction osteogenesis is considered to be a so-called low stress treatment, it is applied also to growing children with maxillofacial deformity. In particular, maxillary distraction has been performed for children with cleft lip and palate often accompanying maxillary deficiency. However, in Japan, there are no reports comprehensively describing the treatment results of maxillary distraction for growing children with cleft lip and palate. The rigid external distraction (RED) system is a typical external device used for maxillary distraction. This review describes the maxillary change on CT images, the hard and soft tissue changes on the profile, and the change of velopharyngeal function after maxillary distraction using the RED system. These examinations revealed that bone formation in the distraction gap was accomplished 6 months after the maxillary distraction, and the postoperative change of the maxilla also tended to reduce simultaneously. However, over the long term after the distraction, reduction of overjet and overbite, and occlusal stability due to mandibular growth were observed. The movement amount of the hard tissue in the distraction was significantly more than that in the conventional surgery. However, the movement ratio of the soft to hard tissue in the distraction was equal to or more than that in the conventional surgery. Although there were no children who had undergone a very large distraction of more than 15 mm, no deterioration of the velopharyngeal function was observed in any of the cases. One of the problems of maxillary distraction in childhood is that it is very difficult to determine the treatment goal because mandibular growth is still progressing. The other problem is that it is difficult to use bone-borne appliances for the maxillary distraction because permanent tooth-germs exist in the maxilla. For the same reason as the latter, bone plate osseointegration after the distraction for reduction of the relapse and early removal of the distraction device is also difficult. In the present review, maxillary distraction of children was performed up to the level of catching up the mandible at the treatment point in time without overcorrection. This was because improvement of the masticatory function was considered to be more important than jaw morphology for growing children. Although it is very difficult to examine how maxillary distraction to catch up the mandible affects the subsequent mandibular growth in relation to improvement of the occlusal and masticatory functions, this problem should be solved when performing maxillary distraction for cleft children in the future.

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Facial morphology improvements are obtained following two-jaw surgery in mandibular protrusion patients. Changing external nasal morphology does not always lead to good results in all patients. In this study, using 3-dimentional computed tomography (3D-CT), we examined the changes of external nasal morphology of patients who had undergone two-jaw surgery to correct mandibular protrusion. Seven adult patients (5 male; 2 female) who had been treated by two-jaw surgery associated with upward transposition of the posterior maxilla were enrolled in this study. 3D analysis software superimposed 3D-CTs of the pre-operative and post-operative stages (at least 6 months after surgery) on the hard tissue surfaces. We employed the 3D coordinate system constructed by Frankfort horizontal (FH) plane, the frontal plane incorporating the orbitals on both sides and the sagittal plane intersecting at the midpoint between the orbitals. After superimposition, soft tissue images of 3D-CT were reconstructed and changes in external nasal morphology were three-dimensionally analyzed. 3D geographical analysis, linear and angular measurements were performed for the most inferior points on the nasal alar (LBi, RBi) on bilateral sides, the most anterior point on the nose (Prn), the most anterior point on the columella of the nose (Cm), the most posterior superior point on the nasolabial curvature (Sn) and the most anterior point on the convexity of the upper lip (Vu). Correlation of hard tissue and soft tissue changes were statistically analyzed by Spearman's rank correlation analysis.
LBi and RBi moved anterior according to the anterior movement of point A. Increase in distance of both LBi and RBi and angle of LBi-Prn-RBi were observed. We found significant increase in the area of external nasal aperture. Positive correlation was seen between the anterior movement of point A and the distance of LBi and RBi.
These results imply that our superimposition of CT images using the 3D coordinate system are useful to compare soft tissue changes before and after surgery. Further investigation for more information about the factors that influence facial morphology changes is necessary since the changes may not be uniform due to the individual variety of soft tissue characterization, and the direction and amount of maxillary movement by Le Fort I osteotomy.

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Objective: We measured the formant frequency of vowels in retrusion patients and normal healthy control patients, and made a comparative study of the purpose in phonology. We wanted to know how orthognathic surgery has influenced the articulation of vowels in patients. We investigated how the relationships between the position of the maxilla and mandible and incisor occlusion affected vowel sounds. And because resonance space is believed to affect sound frequencies, we investigated the effect of the width of the airway preoperatively and postoperatively on vowel sounds.
Methods: Five vowel sounds in 10 Japanese patients with mandibular retrusion requiring surgery for jaw deformity and malocclusion preoperatively and at 3 and 6 months postoperatively were recorded and compared with those in normal healthy control patients. Also, the effect of the positional relationship between the maxilla and the mandible and incisor occlusion on these vowel sounds was investigated by correlating skeletal and denture patterns of cephalometric measurements taken preoperatively and at 3 months postoperatively with these vowel sounds. The width of the airway was measured preoperatively and 3 months after the operation, and the correlation with the frequency of the vowels was examined.
Results: In /e/ F1, /o/ F2-F1, significant differences were observed between the preoperative patients and the control patients. However, these differences disappeared at 3 and 6 months postoperatively.
A significant difference was admitted with F1 of /a/ and F1 of /e/ in comparing the preoperative with the postoperative patients 6 months by a rank test with a sign of Wilcoxon.
Both preoperatively and postoperatively, positive correlations were observed between F2-F1 the narrow, open vowels /i/ with SNA and SNB. In the preoperative patients, some correlations were observed between F1 the semi-narrow, open vowel /e/ and denture patterns.
Significant increases were observed between the preoperative and 3 months postoperative patients in the width of the hypopharyngeal cavity. Many correlations were observed between the change of width of the airway and the vowel frequency, particularly in the posterior tongue vowel /u/. But other vowels had few correlations.
Conclusion: A change of occlusion of the front teeth and a change of frame by the mandible correction operation greatly influenced close vowels and half close vowels that were a front tongue vowel, especially the influence of /i/ and /e/ in retrusion patients. It was an interior tongue vowel that the change in the airway influenced the vowel frequency of only /u/.

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The patient was a 52 years, 11 month old male, who came to our hospital with a chief complaint of an occlusion anomaly on the left side. There was previous medical history of excess secretion of growth hormone due to a pituitary gland tumor that caused acromegaly. The patient was in follow up after a lumpectomy. Molar relationships were Angle Class III. Overjet was -4.0mm and an overbite was -2.0mm. Dental arches were spaced in association with macroglossia. Lateral cephalometric analysis showed skeletal mandibular protrusion and an open bite of the left side. Based on these findings the patient was diagnosed as having a skeletal mandibular protrusion with a left sided open bite associated with acromegaly. Glossectomy, Le Fort I osteotomy and sagittal split ramus osteotomy (SSRO) were planned. Le Fort I osteotomy and SSRO were performed after the lower molar width was reduced with a semi-fixed constriction appliance. Postoperative orthodontic treatment and myofunctional therapy were performed for detailing. The treatment period was 2 years and 2 months. The results showed that the spaces caused by macroglossia were closed efficiently. Maxillary and mandibular dental arch widths were coordinated well and a good occlusion with molar relation of Angle Class I was acquired.

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We report a case of Pruzansky grade II hemifacial microsomia, where a patient had improved facial asymmetry with modified simultaneous maxillomandibular distraction, so-called hybrid osteodistraction.
A female patient was diagnosed with first and second branchial arch syndrome and was followed up at another pediatric hospital. She came to our hospital to receive treatment for facial asymmetry with jaw deformity at the age of 9 years. She had right hemifacial microsomia with her chin distorted on the right side. Examination of her oral cavity revealed occlusal plane inclination and an Angle Class II occlusion. The patient underwent corrective surgery at the age of 14 years after pre-surgical orthodontic treatment was finished.
The first step for this corrective surgery involved Le Fort I osteotomy of the maxilla and removal of a 5 mm cuneiform bone fragment of the left side. Next, the left piriform aperture was loosely wired. This step was followed by right horizontal osteotomy and left sagittal osteotomy of the mandibular ramus. The mandible body was advanced 5 mm in order to improve the Angle Class II occlusion, and an intraoral distractor was placed parallel to the right mandibular ramus. From the third day after surgery, the distractor device was lengthened while the occlusion was maintained by intermaxillary fixation. Using this approach, the integrated maxillomandibular bone could be extended on the right side and shortened on the left side as it rotated. Thus, the patient's mandible was gradually distracted in a vertical vector after instantaneous advance. As a result, facial asymmetry and the tilt of the occlusal plane improved with completed functional occlusion.

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