Abstract
To establish an experimental model of the occlusal trauma of first molar in germ-free mice, crowns of 2nd and 3rd molars were cut or ground.
Histopathological examinations of the periodontal tissue were performed in one day and up to 56 days after the operation.
The results were as follows:
1. The irregular arrangement and the atrophy of the periodontal fibers, the decrease of the cellular components, as well as the destruction of the alveolar bone were the typical changes observed.
2. More consistent results were obtained in the group of mice that had cutting procedure of the crowns than those that had grinding procedure.
3. Pathological or senile changes were not found in the gingival, periodontal and alveolar tissue in control animals.
