乳歯の早期喪失-永久歯の萌出が成熟しているか未熟であるか

[Early deciduous tooth loss--the mature or immature eruption of their permanent successors].

抄録

本研究では，49名の患者の147枚のパノラマX線写真をもとに，乳歯の早期喪失が永久歯の萌出時の後継歯の形成に及ぼす影響を調査した．さらに，萌出時の後継歯の萌出運動についても調査した。その結果、未熟な後継小臼歯の萌出が促進されることに加え、8歳未満の乳歯を抜歯した場合、膿瘍形成を伴う感染乳歯がなければ、永久後継歯の萌出が遅れることが判明した。また、第二乳臼歯の早期喪失による永久歯の萌出移動については、第一永久歯の中側移動と第二永久歯の萌出促進が確認されました。

On the basis of 147 panoramic radiographs of 49 patients, this study investigated the influence of the premature loss of deciduous teeth on the formation of their permanent successors at the time of their eruption. Furthermore the study investigated the eruptive movement of the successor teeth at the time of eruption. In addition to detecting the accelerated emergence of still immature successor premolars, the study also determined that the extraction ot the deciduous molars before the age of eight years delayed the eruption of the permanent successors given the absence of an infected deciduous tooth with abscess formation. In relation to the eruptive movement of the permanent molars due to the premature loss of the second deciduous molar, the study ascertained a mesial movement of the first permanent molars and an accelerated eruption of the second permanent molars.