Twenty-three patients, who had undergone bilateral sagittal split ramus osteotomy (SSRO), and 21 who had undergone intraoral inverted L ramus osteotomy (ILRO), were examined for postsurgical neurosensory disturbances. The neurosensory tests employed included light touch, using a Semmes-Weinstein monofilament tester (SW tester); electrical stimulation, and a questionaire to determine changes in subjective sensations, at the time of each sensory evaluation, in comparison with before surgery. Neurosensory examinations were performed bilaterally (88 sides) at 1, 3, 6 and 12 months after surgery. Both thresholds for the two measurement techniques were lower in the ILRO group than in the SSRO group, at each measurement. The number of sides showing postoperative subjective symptoms was lower in ILRO patients than in SSRO patients, although the difference was not statistically significant. In the SSRO group, at each measurement point, the thresholds for the lower lip and chin were unrelated to the set-back (or advance) distance. By contrast, in the ILRO group, at the 1-month evaluation point, the thresholds for the lower lip and chin were significantly higher than the control level in patients whose set-back (or advance) distances were larger than average (p<0.05). In the ILRO group, whether these distances were large or small made little difference at the other evaluation poits.

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In this study, changes in temporomandibular joint symptoms and mandibular stability after orthognathic surgery in patients with mandibular retrognathism were investigated. Eight patients were examined clinically for pain, sound, movement and limitation of TMJ and by computed tomography (CT) and lateral cephalograms. TMJ signs and symptoms disappeared in two of the symptomatic patients after surgery, whereas two of the asymptomatic patients developed TMJ signs and symptoms postoperatively. The incidences of TMJ signs and symptoms before treatment and a year after surgery were both 3/8 (27.5%). The position of the disk and the condylar morphology were evaluated with CT. Six patients had disk displacements before treatment and seven patients a year after surgery. Erosions and/or deformities of the condyles were observed in six patients before treatment and all (eight) patients a year after surgery. The diagnosis in five patients was progressive condylar resorption because the ramus vertical hights decreased more than 4mm and/or counterclockwise rotation of the proximal segment was observed on the cephalograms, and remarkable resorption was also identified on postoperative CT. There was no association between signs and symptoms of TMJ and CT findings. The mean anterior movement of the mandible at surgery was 10.1mm at pogonion, and the mean horizontal relapse was 4.1mm. Large horizontal relapses were recognized in cases with progressive condylar resorption.
In conclusion, patients with large mandibular advancement and counterclockwise rotation at surgery and condylar erosive bone change at preoperative examination appear to be at risk for progressive condylar resorption, but the mechanism is obscure.

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It is important, for the genioplasty, to make a plan for functional as well as aesthetic improvements because the chin includes not only influential parts of facial the balance but also attachment sites of suprahyoid and labiomental muscles.
Sliding genioplasty with little-detaching suprahyoid and labiomental muscles is useful for the correction of functional and aesthetic problems of chin deformities.
However, a bone graft may be employed in order to move a bony fragment in the anteroinferior border of a mandible, to correct chin deformities.
Porous hydroxyapatite and tricalciumphosphate composite (HAP·ETCP) blocks, designed specially for such cases, can be substituted for a bone graft to stabilize a bony fragment and to improve the soft tissue line of the chin.
None of 17 cases in which functional genioplasty incorporating the implantation of the HAP·ETCP blocks was applied, showed any abnormal clinical courses over three years of observation.
The results of histological and radiological study, which were indicated in some selected cases, substantiated the unproblematic clinical course of this treatment.

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A 33-year-old female had a class II malocclusion with a severe unilateral scissors bite. Initial records showed the overerupted upper left premolars and molars, and lingo-inclined lower left premolars and molars. The lower first molars and the second molar of the right side were missing. The upper left molars impinged on the buccal gingiva of the lower arch in habitual occlusion. She also complained of difficulty of closing her lips. Orthodontic treatment followed by surgical procedures was performed. Extraction of the upper first premolars was performed at first for the elimination of crowding in the upper arch, and then one of these teeth was transplanted to the lower right posterior segment as the orthodontic anchor. After the alignment of the upper arch, the upper left posterior segmental osteotomy and the lower left posterior segmental corticotomy were performed for the correction of the scissors bite. The lower left posterior segment was expanded buccally after surgery, and then the upper and lower anterior segments were retracted orthodontically. Finally fairly good functional occlusion was obtained, and her lips could be competent at rest.

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This patient was diagnosed as having sleep apnea syndrome with micrognathia caused by mandibular ankylosis. At the age of 22 years and 3 months, 18mm of mandibular body lengthening was performed, by distraction osteogenesis, during a period of 20 days. Four months after the distraction, the devices were replaced with titanium miniplates.
Ultrasonic evaluation was conducted every week, to estimate the bone formation. Distance and area measurement were performed with lateral cephalograms taken before and after the distraction, to analyze the augmented volume of bone. In addition, polysomnography and a pulse-oximeter were used to monitor physiological functions.
As a result, the mandible was distracted forward, and significant improvements of the apnea and the profile could be seen.

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We report an experiment using the Titanium Cranio Maxillofacial System (CMS^TM) for orthognathic surgery.
We had very good results using the CMS^TM for orthognathic surgery.
We used the CMS^TM system for fixation, even thin bone grafts to 47 cases, and we examined the stability of Le Fort I osteotomy from cephalometric analysis (12 patients). All of the patients had cephalograms taken immediately post-operatively and at after-three-months follow-up visits.

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