ラット上下顎臼歯歯根膜の機械的強度に及ぼすβ‐ａｍｉｎｏｐｒｏｐｉｏｎｉｔｒｉｌｅ（ＢＡＰＮ）経口投与の影響

Abstract

Changes in the ultimate loads required to extract the mandibular and maxillary 1st, 2nd and 3rd molars from the dissected jaws were examined 1, 2, 4, 8, 16 and 24 days following oral administration of a lathyrogen, beta;-aminopropionitrile (BAPN). The average amount of water taken by the rats was fairly constant but because their body weight increased during the experimental period, the average dose of BAPN decreased gradually from 331 to 192mg/Kg b. w. In the control groups, the ultimate loads increased gradually from the beginning to the end of the experimental period. They were 34.4, 26.9 and 13.6N (newtons) in the mandibular 1st, 2nd and 3rd molars and were 34.2, 30.6 and 18.0N in the maxillary 1st, 2nd and 3rd molars respectively at the end of the experimental pe-riod. In the experimental groups, they were 9.9, 10.2 and 8.4 N in the mandibular 1st, 2nd and 3rd molars and were 13.5, 14.6 and 10.9N in the maxillary 1st, 2nd and 3rd molars respectively at the end of the experimental period. The biggest values of the percentage reductions of the ultimate loads were 73, 71 and 51 in the mandibular 1st, 2nd and 3rd molars and were 64, 58 and 64 in the maxillary 1st, 2nd and 3rd molars respectively during the experimental period. From an analysis of the results, it is suggested that the effects of BAPN appeared rather rapidly in the teeth with imm ature periodontal ligaments and that the functioning teeth tended to be affected more severely by the drug