RADIATION EFFECTS ON DENTIN FORMATION OF RAT INCISORS
1984 Volume 24 Issue 2 Pages 100-113
Details
1984 Volume 24 Issue 2 Pages 100-113
Wistar strain male rats weighing about 100g were used in this study. The heads of the animals were irradiated with single dose from 25rad (0.25Gy) to 1000rad (10Gy) under the following conditions; 100kVp, 4mA, Filter: 0.1mmCu+0.5mmAl, FSD: 30cm, HVL: 3.5mmAl. The dentin and odontoblasts on the labial sides of maxillary incisors were observed with light-, fluorescence-, electron-microscope and microradiography.
The following results were obtained:
1) The minimal absorbed dose affecting the dentin formation was 100rad (1Gy), which was the lowest dose compared with the previous investigations.
2) Dentin hypoplasia was found remarkably as the absorbed dose increased.
3) The most radiosensitive cells were prefunctional preodontoblasts which were differentiating papilla cells with polarizing nuclei and without capacity of predentin-formation, and the second radiosensitive were preodontoblast precursors.
4) The alterations of nuclei and cytoplasm became severe as the absorbed dose and the lapse of days after irradiation increased.
