The purpose of the present study was to investigate the effect of a fine-grained diet on the rabbit maxillofacial skeleton. Twelve male Japanese white rabbits, at age 5 weeks (juveniles), were used for the experiment. Six of these rabbits were fed a finegrained diet, as the experimental group, and the other six were fed a normal hard diet (pellet form), as the control group. Both groups were raised until 18 weeks (adults, 3.0kg). Maxillofacial skeletons of the two groups were compared using standardized digital photographs.
The characteristics of the experimental group were as follows:
1) The zygomatic arch width and the area of the facial tuber that related to the attachment of the masseter muscle were smaller compared with the control group.
2) The mandiblar ramus width was significantly smaller, and the mandibular body-ramus angle was larger, in the experimental group than in the control group.
3) In the superimposition of the lateral view, the point of the lower incisor lingual cervical line was shifted forward. The apex of the angle process was shifted forward; however, there were no significant differences in the positions of the mandibular condyle and the mandibular fossa.
4) In the superimposition of the frontal view, the lowest points of the mandibular angle showed laterotrusion.
These findings suggested that the morphological features of the rabbit, raised on a fine-grained diet, especially the attachment of the masticatory muscle, were altered by decreasing the functional masticatory load.

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The purpose of this study was to investigate soft tissue changes in the nose and upper lip following maxillary alveolar osteotomy. The subjects selected for this study were 20 maxillary protrusion cases, which underwent two different treatment modalities: A surgical group, consisting of 10 subjects treated with a combination of maxillary alveolar osteotomy and orthodontic treatment, and an orthodontic group, consisting of 10 subjects treated with only orthodontic treatment after 4 bicuspids were extracted.
For each patient, lateral cephalograms before and after treatment were traced and superimposed, and linear and angular measurements were obtained, and the data from the two groups were compared. We further evaluated the relationship between changes of the hard and soft tissues in each group. The results were as follow:
1. After treatment, point A and the prosthion were significantly moved backward, in the surgical group, compared with the orthodontic group.
2. There was no significant change of the pronasale in both groups. In the surgical group, subnasale were significantly more retracted than in the orthodontic group. Nasal height increased more in the surgical group than in the orthodontic group. Although there was a significant positive correlation between subnasale and point A retraction in the surgical group, there was no correlation in the orthodontic group.
In conclusion, compared with orthodontic treatment, an anterior maxillary osteotomy influences the subnasale by retracting it posteriorly, consequently increasing nasal height and improving the overall facial profile appearance.

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Macroglossia and abnormal posture of the tongue are considered to be etiological factors that lead to skeletal openbite. Furthermore, both factors influence the stability after orthognathic surgery. This is a case report of an 18-year-old male patient with anterior open-bite and mandibular prognathism. He underwent surgical orthodontic treatment combined with mandibular body ostectomy and glossectomy. No relapse was observed after a mandibular counterclockwise rotation procedure.

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The study examined the stability of a bioabsorbable osteosynthesis system after surgical correction of jaw deformity. Nine patients received sagittal splitting ramus osteotomy (SSRO), fixed with a bioabsorbable poly-L-lactide (PLLA) osteosynthesis system. Of these, three received simultaneous Le Fort I osteotomy. A control group, of eleven patients, received SSRO. Of these, six received simultaneous Le Fort I osteotomy, fixed titanium plates, and screws. Stability after surgery was analyzed cephalometrically. There was no significant difference in postoperative stability between the two groups, not only in cases of SSRO alone but also in cases of SSRO with Le Fort I osteotomy. These results indicate that the PLLA osteosynthesis system can be used effectively in surgery for jaw deformity.

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