上颌埋伏倒置中切牙3例及文献复习

目的探讨上颌埋伏倒置中切牙病例的临床特点、诊断及治疗方法，以期为临床诊治提供参考。 方法回顾性分析南方医科大学附属深圳妇幼保健院2017—2019年期间收治的3例上颌埋伏倒置中切牙患者的临床表现、影像学表现、治疗方法及治疗效果，并进行相关文献复习。 结果3例上颌埋伏倒置中切牙病例主要表现为单侧上颌中切牙缺失、邻牙倾斜、缺牙间隙变小，锥形束CT（CBCT）检查均发现缺隙处有1颗唇侧倒置埋伏中切牙，其中1例牙根根尖孔已闭合，另外2例牙根发育至根尖1/2 ~ 1/3，现有冠根比≥1∶1，牙根弯曲部分在根尖1/2 ~ 1/3。3例均采用外科开窗联合正畸牵引进行治疗，患牙均顺利进入牙列，无松动，咬合良好，未出现明显牙根吸收。 结论上颌埋伏倒置中切牙的矫治难度较大，应掌握其临床特点及治疗原则，重视矫治时机的选择及矫治方法设计，提高患牙保存率。

Inversely impacted maxillary central incisor: three case reports and literature review

ObjectiveTo investigate the clinical characteristics, diagnosis and therapeutic methods of inversely impacted maxillary central incisor cases, further to provide reference for clinical work. MethodsThe clinical manifestations, imaging manifestations, therapeutic methods and therapeutic effects of three cases of the inversely impacted maxillary central incisor which were collected from 2017 to 2019 in the Affiliated Shenzhen Maternity and Child Healthcare Hospital, Southern Medical University were retrospectively analyzed and related literature was reviewed. ResultsThe main clinical manifestations of the three cases were the loss of unilateral maxillary central incisor, with the adjacent teeth tilted and the edentulous space reduced. Cone-beam computed tomography (CBCT) showed that the three cases were labial impacted teeth. In one case, the apical foramen of the impacted tooth was closed, in the other two cases, the root of the impacted teeth developed to the 1/2 ~ 1/3 of the root tip. The crown-root ratios of the impacted teeth were≥1∶1 and the root curves were at the 1/2 ~ 1/3 of the root tip. Surgical exposure combined with orthodontic traction were used in the three cases. The teeth of the three cases were moved into arches without loosening of the teeth and root resorption, establishing good occlusal relationship. ConclusionsThe treatment of the inversely impacted maxillary central incisor was difficult. Doctors ought to master the clinical characteristics and therapeutic principle, paying attention to the treatment timing of these cases, in order to improve the preserving rate of the inversely impacted maxillary central incisor.