Rasmussen P, Kotsaki A
Department of Pedodontics, School of Dentistry, University of Bergen, Norway.
J Clin Pediatr Dent. 1997 Spring;21(3):205-11.
The term retarded eruption, may be used in cases where eruption is inhibited, causing an interruption in the coordination of tooth formation and tooth eruption. The phenomenon may be local or general, and several etiological factors for retarded eruption have been listed, comprising a lack of space, ankylosis, cysts, supernumerary teeth, hormone and vitamin deficiencies and several developmental disturbances and syndromes. The present paper describes several cases of retarded eruption where no factors other than inheritance have been evident. So far 14 cases have been evaluated, 9 boys and 5 girls. In addition several cases have been registered among parents and grandparents of the probands. Typical features are: retarded eruption, defined as more than 3 SD beyond mean eruption figures, comprises all teeth in the permanent dentition, and in 5 cases also second primary molars. The chronology of tooth formation are within normal limits. Consequently the teeth finish development still laying deeply buried in the jaws, often in aberrant positions and with curves or hooks on the roots. When the teeth finally get the "signal" for eruption, 5-15 years beyond normal eruption time, they move rather quickly into right positions, despite the long eruption paths and the hooked roots. Permanent teeth without, as well as with predecessors, are affected. Extraction of predecessors does not seem to provoke eruption. The main features in management are to take care of the primary teeth, to improve-esthetics, and offer surgery and orthodontics when needed. Analyses of pedigrees indicates that the genetic transmittance may be autosomal dominant as both sexes are affected, about half of the siblings show the trait, and the trait shows continuity through generations.
萌出迟缓这一术语可用于描述萌出受到抑制，导致牙齿形成与萌出协调过程中断的情况。这种现象可能是局部性的或全身性的，已有多种导致萌出迟缓的病因被列出，包括空间不足、牙齿粘连、囊肿、多生牙、激素和维生素缺乏以及一些发育障碍和综合征。本文描述了几例除遗传因素外无其他明显因素的萌出迟缓病例。到目前为止，已评估了14例，其中9名男孩和5名女孩。此外，在先证者的父母和祖父母中也记录了几例。典型特征如下：萌出迟缓定义为超过平均萌出数据3个标准差以上，包括恒牙列中的所有牙齿，5例中还包括第二乳磨牙。牙齿形成的时间顺序在正常范围内。因此，牙齿在发育完成后仍深深埋在颌骨中，常常处于异常位置，牙根有弯曲或钩状。当牙齿最终获得萌出“信号”时，比正常萌出时间晚5至15年，尽管萌出路径长且牙根有钩状，但它们仍能相当迅速地移动到正确位置。有无乳牙的恒牙均受影响。拔除乳牙似乎不会促使恒牙萌出。治疗的主要要点是保护乳牙、改善美观，并在需要时提供手术和正畸治疗。系谱分析表明，这种遗传传递可能是常染色体显性遗传，因为男女均受影响，约一半的兄弟姐妹表现出该性状，且该性状代代相传。
