乳歯列期下顎骨の放射線障害に関する実験的研究

概要

論文の詳細を見る
In order to make a radiological and histopathological investigation of radiation injury to jaw bones at growth stage, the region of left mandibular third deciduous tooth of young dogs were irradiated for 3, 000R with 200kVp X-ray. The results were as follows : 1. In the periodontal tissue of deciduous teeth, inflammatory cell infiltration was observed in the periodontal membrane on 12th day after irradiation. Thereafter, with progress in bone resorption, proliferation of cementum and alveolar bone was seen at 4th month. At 8th month, prolifered alveolar bone filled the periodontal membrane space and infiltrated into the region where root dentin was resorbed. Radiologically, this finding was shown as narrowing of the periodontal membrane space of deciduous teeth. 2. Resorption of deciduous teeth from the root apex, although slight, was seen at 4th month. At 8th month, resorption due to proliferation of the alveolar bone was seen markedly on the mesio-distal side of the root apex. Ankylosis of the proliferated alveolar bone and the deciduous tooth root was observed. This finding was thought to cause persistence of deciduous teeth. 3. As injury to the cortical bone, resorption in moth-eaten pattern and vacuolation or enlargement of bone lacunae were observed at 2nd month. At 4th month, however, resorption and vacuolated bone lacunae decreased and new Haversian system was also seen at 8th month. Radiological findings of coarsening and resorption were observed delayed when resorption in moth-eaten pattern appeared. When new Haversian system appeared, cortical bones appeared normal in radiograms. 4. As injury to the alveolar bone, radiological finding of irregular trabeculae was seen on 9th day and spotty bone resorption was seen at 2nd month. Irregular trabeculae was due to resorption of the alveolar bone. Spotty bone resorption image was the finding seen at the time bone resorption and new bone were observed concurrently. When new Haversian system was seen in the alveolar bone at 8th month, spotty bone resorption image became more marked. 5. Formation of fatty marrow began on 12th day after irradiation of bone marrow. About at 2nd month, fibrous marrow was observed and inflammatory cell infiltration was seen there. Resorption of bone trabeculae was due to appearance of osteoclasts and the appearance of osteoclasts was closely related with inflammatory cell infiltration. 6. As changes in the inferior alveolar artery, extension of elastic fibers and looseness of circular tunica media were seen between 1st and 4th month. At 8th month findings were nearly normal. 7. As injury to tooth germ of permanent teeth, hyper-calcification image resulting from early completion of calcification of dentin at the crown portion was observed. Root formation stopped at 2nd month. The root region was obstructed by osteodentin and root formation was no longer observed thereafter. On the basis of the foregoing findings, it was made clear that radiation injury to the jaw bones at growing stage was closely related with development of the jaw bones and teeth.
九州歯科学会の論文
1986-08-25

乳歯列期下顎骨の放射線障害に関する実験的研究

スポンサーリンク

概要

著者

関連論文

スポンサーリンク