A 23-year-old female whose chief complaint was asymmetric prognathism with temporomandibular joint disorder (TMD) underwent surgical orthodontics using sagittal splitting ramus osteotomy. A symmetric skeletal relationship and good occlusion were obtained. MRI and tomogram were taken before and after the treatment to evaluate condylar position. Concomitantly condylar movements were recorded with maximum opening and protrusion-retrusion of the mandible by means of a computer-aided diagnostic axiograph (CADIAX). The results indicated that the distance of condylar path tracing in maximum opening and protrusion movements decreased and the asymmetry of condylar movement was corrected after surgerv.

View full abstract

In orthodontic treatment, not only improved functional malocclusion but also esthetic facial balance is important. In addition to the morphology of the anterior facial region, that of the cervicomental region seems to be an important factor in the patients with jaw deformity when the craniofacial region as a whole is taken into consideration.
The purpose of this study was to establish standard values for determining the soft tissue profile of the cervicomental region in selected Japanese adults with normal occlusion by means of cephalometric analysis of the lateral cephalogram.
Results:
1. There was no significant difference in both lip-chin-throat and cervicomental angles between the male and the female subjects with normal occlusion. The lip-chin-throat angle was 113.2 ± 6.76°, and the cervicomental angle was 116.6 ± 9.94°.
2. The mean value of throat length was 35.2 ± 3.68mm. It was 36.57 ± 3.60mm in the male and 33.36 ± 3.01mm in the female. The male-female difference was significant only for throat length. This study established standard values for the cervicomental region in the Japanese adults with normal occlusion. This is considered to be one of the items that should be examined in case of genioplasty in the future.

View full abstract

Micrognathia with mandibular asymmetry is caused by either acquired or congenital underdevelopment of the mandible before adolescent growth spurt. The facial deformity develops progressively until the end of growth resulting in a bird face appearance associated with facial asymmetry, and surgical-orthodontic treatment is indicated for reconstruction of the unfavorable facial morphology and occlusion in such cases. This report describes a surgical-orthodontic treatment of a patient of micrognathia with mandibular asymmetry.
The patient was a 23-year 5-month-old female who had the chief complaint of facial asymmetry and masticatory dysfunction. The underdevelopment of the mandible on the shifted side might have been caused by inflammation of the mastoid process in infancy. Radiographic examinations depicted a severe deformity of the right mandibular ramus, condyle and mandibular body, and cystic appearances in the apical region of the lower anterior teeth. After preoperative orthodontic treatment, surgical treatment was performed employing mandibular sagittal split ramus osteotomy combined with an osteotomy for midline correction. The shifted side of the mandible was advanced, and the lower edge of the mandibular body on the contralateral side was rotated and twisted outward in this treatment. Eight months later, midline osteotomy was performed again to detail the facial symmetry. The resultant Class I occlusion was apparently stable for a long time. Improvement in masticatory function and facial esthetics was successfully obtained in this case.

View full abstract

Orthognathic surgery was performed on 362 patients from 1987 to 1997 at the Second Department of Oral and Maxillofacial Surgery, Osaka Dental University.
The results were as follows: 1. The male-female ratio was 1: 2.4.
2. The mean age was 22.4 years old.
3. The diagnosis of mandibular prognathism was made for most of the patients (89.2%).
4. Sagittal splitting ramus osteotomy (SSRO) was performed on 274 cases (75.7%).
5. The mean time of operation for SSRO was 3hr. 7 min±57min, and for mandibular body osteotomy was 3hr. 15min±60.7min.
6. The mean blood loss during operation for SSRO was 275.8±221.4ml and for mandibular body osteotomy was 171.8±147.5ml.
7. Paresthesia of the lip and mental area was observed in 404 sides after opration. 80.7% of patients treated for SSRO recovered within a year.
8. TMJ were examined in 202 cases for 1 year after SSRO. The symptom of TMJ was recognized in 5 cases.

View full abstract