|Budget Amount *help
¥2,200,000 (Direct Cost : ¥2,200,000)
Fiscal Year 1995 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1994 : ¥1,400,000 (Direct Cost : ¥1,400,000)
Insulin-dependent juvenile diabetes mellitus (IDDM) patients are increasing and orthodontic treatment of these patients are also increasing in Japan. It is indicated that the orthodontic stimulation in the IDDM tends to get delay and that the force control is difficult clinically. The purpose of this study is to examine histopathologically the effects of experimental tooth movement and lateral expansion in the spontaneously rat (BBrat) with insulin therapy. Throughout the experimental period these BBrat were controlled every day with intravenous human insulin injection of 2-6U after diabetic attacks. Wistar-strain rats were used as a control.
1. In the experimental tooth movement, the upper first molar (M1) was mesially moved to using Ni-Ti closed coil spring with about 10g for 1,3,5,7,10,14,21 and 28 days. 2. In lateral expansion, an expansion device was installed between maxillary incisors for 2 days. The expansion space was retained for 1,3,5 and 7 days. Atter the experiments, all an
imals were sacrificed and the specimens were examined with the light microscope.
The results were as follows ; 1. The distance of tooth movement in BBrat groups was the same in control group till 5 days after tooth movement. But after 14 days, in the control group, the distance of tooth movement was much more than significantly larger than that in BBrat group. 2. In control group, the bone resorption of a pressure side and the bone formation of a tension side were more active than those of BBrat group from 5 days after tooth movement. The hyaline degeneration of a pressure side was retarded for a long term in BBrat group. 3. After lateral expansion, in control group, many fibroblasts and osteoblasts were actively observed in the sutural space, as compared with the BBrat group. In control group, the new bone formation and restoration were active and extensive in the sutural space.
It was suggested that the bone resorption, bone formation and remodeling following tooth movement and lateral expansion are retarded regardless of the control of blood glucose levels with insulin in IDDM patients. Less