[The effect of artificial traumatic occlusion on the pulp and periodontium in rat molars].
In order to study relationship between the period of occlusal trauma and pulpal and periodontal tissues, 44 rats were used in experimental occlusal trauma. The pulpal and periodontal tissues of rat molars were observed by histological examination and micrographic examination. The results showed that the damage of pulp became more serious as time went on, but periodontium appeared adaptive changes. The same changing area in periodontal tissues were observed between histological section and micrographic film. The results provide experimental evidences for the pathology and pathogeny of pulpitis and perioapical periodontitis caused by occlusal trauma.