Effects of dietary consistency on the mandible of rats at the growth stage: computed X-ray densitometric and cephalometric analysis.

Thirty 3-week-old male Wistar rats were grouped into a hard diet control group, a kneaded-diet group, and a powdered-diet group. After 6 weeks of growth, all rats were killed under deep anesthesia. The effects of dietary physical consistency on the mandible were investigated with respect to morphology and bone mineral content using lateral cephalometric analysis and computed X-ray densitometry. Significant differences between the experimental and control groups were determined by measuring the means and standard deviation of the coordinates and differences between 15 points selected on the mandibles. Gonion (Go), which is a measurement of depth to the X-axis, was significantly less in the powdered-diet group, while the kneaded-diet group showed no significant differences. The most posterior point of the coronoid process (Cr) and the most posterior point of condylar process (Cd), which are measures of height to the Y-axis, were less in the kneaded-diet group than in the control group. In the powdered-diet group, Cr, Cd, Go and Infradentale were significantly less than in the control group. On the other hand, the bone mineral content was significantly lower in the coronoid process and angle of mandible in only the powdered-diet group.