Destruction and repair of periodontal tissues during burst episodes of activity in hamster XXXX .

@entity604 @entity133 @entity79 @entity329 @entity2521
This study describes episodes of rapid destruction and repair of periodontal tissues occurring during the course of hamster @entity2521 . The mandibular molar periodontia of 120 male @entity329 exposed to Keyes 2000 diet for periods ranging from 45 to 180 days were examined on undecalcified serial sections. The destructive phase of the episodes was characterized by the localized appearance of a large number of osteoclasts creating a cone-shaped defect. Bone resorption was associated with disorganization of the gingival tissues, including epithelial ulceration, and a dense PMN infiltration. The repair phase was observed in these cone-shaped defects by the use of fluorescent and corresponding stained sections. Bone formation was intense with woven bone filling the cervical aspect of the defect. Apically, bone formation was more regular and less rapid. A healthy band of connective tissue always separated the bone reaction from the infiltrated connective tissue. Despite its magnitude this repair did not restore the overall @entity79 . The burst episodes of activity were found far more frequently in animals with significant macroscopic @entity604 . They mobubly play a key-role in the progress of @entity133 in the hamster.
