Kohavi D, Dikapua L, Rosenfeld P, Tarazi E
Oral Implant Center, Dept. of Prosthodontics, Hebrew University-Hadassah School of Dental Medicine, Jerusalem.
Refuat Hapeh Vehashinayim (1993). 2003 Jul;20(3):70-8, 103.
Various statistics have shown that avulsion (total displacement of tooth out of its socket) following traumatic injuries is relatively infrequent, ranging from 0.5 to 16% of traumatic injuries in the permanent dentition. The maxillary central incisors are the most frequently avulsed teeth. Avulsion of teeth occurs most often in children from 7 to 9 years of age, when the permanent incisors are erupting. Most frequently, avulsion involves a single tooth; but multiple avulsion are occasionally encountered. Fractures of the alveolar socket wall are often associate with avulsion. After the tooth is lost, an almost certain sequelae is the rapid resorption of alveolar bone. In many cases, only a very thin crestal bony lamella remains after healing of the alveolus, with clinically obvious horizontal and vertical depressions. In a young patient missing an anterior tooth, the operator may find implant insertion, in the proper anatomical position, difficult or impossible, because of inadequate bone volume. This situation aggravates with time because of continuous resorption and relative growth of the adjacent alveolar bone around the teeth. New and predictable bone augmentation techniques allow compensation for bone reduction while waiting for completion of growth. In cases of localized ridge augmentation, the amount of initial bone volume and its shape dictate whether implant insertion and bone augmentation will be performed simultaneously. The indications for this approach are: sufficient bone volume to achieve initial implant stability and a predictably high success rate for the augmentation. When bone volume and shape do not allow for initial stability, there is indication for a staged approach, in which the bone is initially augmented, the results are evaluated and the implant is then inserted. The first stage, the bone regeneration phase, may last between 8-10 months. The second, the implant integration period, may take an additional 6-8 months. The effect of growth on the augmented bone is not quite clear and there is only a paucity of information concerning the use of bone regeneration procedures in growing patients. Clinical decision when to start implant treatment after avulsion is dependent not only on the timing of implant insertion, but also on bone regeneration procedures. When most of horizontal and vertical bony walls of the extraction site is lost, augmentation procedure as a measure to reduce the deficiency, may be considered even in preadolescents. Three cases describing different clinical situations following avulsion, tooth replacement, resorption, regeneration treatment and implant insertion are discussed.
各项统计数据表明，外伤后牙脱位（牙齿完全从牙槽窝中移位）相对少见，在恒牙列外伤中占比0.5%至16%。上颌中切牙是最常发生脱位的牙齿。牙齿脱位最常发生在7至9岁的儿童，此时恒牙正在萌出。最常见的是单个牙齿脱位，但偶尔也会遇到多个牙齿脱位的情况。牙槽窝壁骨折常与牙脱位相关。牙齿脱落后，几乎必然的后遗症是牙槽骨的快速吸收。在许多情况下，牙槽愈合后仅残留非常薄的牙槽嵴骨板，临床上会出现明显的水平和垂直凹陷。对于缺失前牙的年轻患者，由于骨量不足，手术者可能会发现在合适的解剖位置植入种植体困难或无法植入。由于牙槽骨的持续吸收以及牙齿周围相邻牙槽骨的相对生长，这种情况会随着时间加剧。新的、可预测的骨增量技术能够在等待生长完成的同时补偿骨量减少。在局部牙槽嵴增量的情况下，初始骨量及其形状决定了是否将同时进行种植体植入和骨增量。这种方法的适应证为：有足够的骨量以实现种植体的初始稳定性，且骨增量有可预测的高成功率。当骨量和形状无法实现初始稳定性时，则表明需要分阶段进行，即首先进行骨增量，评估结果后再植入种植体。第一阶段，骨再生期，可能持续8至10个月。第二阶段，种植体整合期，可能还需要6至8个月。生长对增量骨的影响尚不完全清楚，关于在生长中的患者中使用骨再生程序的信息也很少。外伤后何时开始种植治疗的临床决策不仅取决于种植体植入的时机，还取决于骨再生程序。当拔牙位点的大部分水平和垂直骨壁缺失时，即使是青春期前的患者，也可考虑采用增量程序作为减少骨量不足的措施。本文讨论了三个描述牙脱位、牙齿替换、吸收、再生治疗和种植体植入后不同临床情况的病例。
