The purpose of this study was to compare the skeletal and dentoalveolar changes in skeletal class III patients who underwent only orthodontic treatment, with those in patients who received both orthodontic treatment and orthognathic surgery, and to identify a critical point in the treatment of skeletal class III malocclusion. Fifteen skeletal class III patients who underwent both orthodontic treatment and orthognathic surgery (mean age, 18.4 years; the surgical group), and 14 skeletal class III patients who underwent only orthodontic treatment (mean age, 18.1 years; the orthodontic group), were included in this study. They were treated by the multi-bracket edgewise technique without premolar extraction. Angular and linear cephalometric variables were measured, using lateral cephalograms, for each patient, taken before and at the end of the active orthodontic treatment. Unpaired and paired t-tests were used for statistical analysis. Before treatment, there were no significant differences in any of the cephalometric variables between the surgical and orthodontic groups, except for overjet. Significant changes commonly observed in both groups were a decrease in SNB, an increase in ANB, clockwise rotation of the mandible, counterclockwise rotation of the occlusal plane, and an increase in overjet. On the other hand, a significant increase in U1-FH, and a significant decrease in Ll-Mand. were found only in the orthodontic group. With regard to the extent of the change during treatment, the changes in SNB, ANB, Wits appraisal, and overjet were significantly greater in the surgical group than in the orthodontic group, whereas the changes in U1-FH and the functional occlusal plane angle were significantly greater in the orthodontic group than in the surgical group. Moreover, significant differences were also seen inL1-Mand. and overbite. These results suggest that counterclockwise rotation of the functional occlusal plane is the critical change in the orthodontic treatment of skeletal class III patients without orthognathic surgery, in addition to conventional skeletal and dentoalveolar changes, such as in the anteroposterior jaw relationship and the inclination of anterior teeth.

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The purpose of this study was to examine the differences in craniofacial structures at the prepubertal stage between skeletal class III patients treated only orthodontically (orthodontic group) and patients who received both orthodontic treatment and orthognathic surgery (surgical group) following growth control with a maxillary protraction appliance. The surgical group consisted of 5 males and 6 females (mean age, 9.8 years), and the orthodontic group consisted of 6 males and 11 females (mean age, 8.5 years). Cephalometric variables for evaluating skeletal and dentoalveolar structures were measured using lateral cephalograms taken at the first visit. The unpaired t-test and multiple-regression analysis were used for statistical analysis. With regard to skeletal cephalometric measurements, the gonial angle was significantly larger, and Wits appraisal was significantly smaller, in the surgical group compared with the orthodontic group. Although no significant difference was found in dentoalveolar cephalometric measurements, the functional occlusal plane tended to be steeper in the surgical group.The results of multiple-regression analysis indicated that Wits appraisal could be used to effectively discriminate between the two groups. Furthermore, none of the patients in the orthodontic group had a Wits appraisal value below-15mm. These results suggest that Wits appraisal may be useful for deciding whether to apply surgical or orthodontic treatment in the future at the prepubertal stage.

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The purpose of this study was to examine dentofacial changes treated by orthognathic surgery, and to clarify morphological factors affecting the stability of postoperative occlusion.
Seven adult patients treated by surgical orthodontics using symmetrical mandibular advancement with the Obwegeser sagittal osteotomy, were selected for this study. Lateral cephalograms taken at five stages: pre-treatment, immediately before and after surgery, at the beginning of retention, and under retention (more than one year after retention began), were used for quantitative evaluation of dentofacial changes.
Changes in dental and skeletal components, and anterior occlusion at each period, were analyzed in the anteroposterior and vertical dimensions, respectively.
The following results were obtained:
1. During the preoperative orthodontic treatment period, a remarkable correction of the malpositioned maxillary and mandibular incisors, associated with a little mandibular displacement, contributed to the change in the anterior occlusion.
2. Before and after surgery, marked improvement in anterior occlusion was completed by the surgical mandibular advancement. In some cases, positional changes in the maxillary and mandibular incisors were found in both the anteroposterior and vertical dimensions, leading to a skeletal relapse of the mandible.
3. During the postoperative orthodontic treatment period, a tendency of skeletal relapse was found. However, the anterior occlusion was generally stable because of compensatory changes in the dental components by the postoperative orthodontic treatment.
4. During the retention period, a notable deterioration in the anterior occlusion was found in a case presenting condylar resorption. Except for this case, the overjet was stable due to the compensatory changes in the dental components for the skeletal relapse, while the overbite was unstable because of the dental relapse.
The postsurgical stability of the anterior occlusion could be affected by the dentoskeletal relapse due to the amount of advancement, inadequate postoperative position of the condyle, fixation technique, and condylar resorption.

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Several attempts to make three-dimensional reconstructions using lateral and frontal cephalograms have been made. However, these did not sufficiently express the morphological features because of problems in magnification and distortion of the cephalograms.
In this study, we introduce a new method to construct three-dimensional hard tissue and soft tissue images from cephalograms and facial photographs. This new method was employed to perform computer simulation for patients with mandibular prognathism who underwent sagittal splitting ramus osteotomy (SSRO).
The advantages of this system were as follows:
1. A prototype model was constructed based on the coordinates of anatomical landmarks registered on three-dimensional computed tomography (3D-CT). Respective points obtained from cephalograms and facial photographs were superimposed on the prototype model, and then an interpolating procedure was performed between points after fitting the point each other, and then the morphological feature of the patient was extracted.
2. With the present three-dimensional integration system, a wire-frame model was used to represent the hard and soft tissues of the maxillofacial structure. As a result, we made it possible to reproduce the three-dimensional integrated model on a personal computer and view the structure from any desired angle.
3. The simulated postoperative skeletal and facial images were similar to the actual ones obtained after surgery. Thus, we believe that employing this new method will provide easy-to-understand information to patients and establish a method for communication with oral surgeons and orthodontists.

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A 19-year-old patient with hypernasality was reported before and after two-jaw surgery to evaluate the effects of the surgery on her speech. Cephalometric analysis was made of the oropharyngeal and hypopharyngeal areas, in addition to assessing her articulation and velopharyngeal function by nasopharyngeal fiberscopy. Results of the analysis indicated that maxillary advancement plus mandibular setback caused no adverse effect on articulation, or on velopharyngeal function, whereas the anteroposterior width of the oropharyngeal orifice increased, and hypopharynx cross-sectional areas decreased.

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Synovial chondromatosis is a disease of cartilagenous metaplasia of the synovial membrane accompanied with loose bodies within the articular cavity. It occurs frequently in the knee, elbow, and hip joints. However, reports of this lesion of the temporomandibular joint (TMJ) are rare.
A 21-year-old woman visited our hospital complaining of facial asymmetry, malocclusion, and a clicking sound in the left TMJ region. Her purpose was to undergo treatment of orthognathic surgery. But panoramic radiography, 3D-CT, and MRI revealed calcified loose bodies surrounding the condyle of the left TMJ.
After an intraoral vertical left ramus osteotomy was performed (IVRO), removal of all loose bodies, a synovectomy and a discectomy were performed, using the Al-Kayat-Bramley technique. The loose bodies totaled 88 white nodules measuring 3 to 7mm in diameter. Histological examination of the loose bodies demonstrated cartilagenous metaplasia. Using this technique, this patient was made free from disease and functional disturbances of the TMJ, and at the same time she had an improved facial and occlusal form after surgery.

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