Abstract
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.
