上颌前牙区多生牙的锥形束CT影像学特征研究

Study on the radiographic characterizations of supernumerary teeth in maxillary anterior region using cone beam computed tomography

目的 利用锥形束CT(cone beam computed tomography,CBCT)分析上颌前牙区多生牙(supernumerary tooth,ST)的影像学特征,为ST的治疗提供帮助。方法 共收集805例CBCT数据,利用专用软件NNT评价ST的影像学特征,包括:数目、形态、位置、方向、发育情况和并发症,并分析上述影像学特征的性别差异。结果 男女比例2.96∶1,男性和女性ST均以单枚、锥形、牙弓腭侧、倒置和阻生为主,但男性发生2枚ST的比例显著高于女性(P<0.001),女性ST倒置的比例更高(P<0.001)。最常见的ST相关的并发症是鼻腭管管壁骨质吸收,且男性高于女性(P=0.01)。此外,ST累及解剖结构及相关临床并发症还包括鼻底骨质吸收,形成颌骨囊肿,牙滤泡间隙增宽,邻牙阻生、移位或扭转、根吸收。结论 男性和女性上颌前牙区的ST以单枚、锥形、牙弓腭侧、倒置和阻生为主,但发病特点存在性别差异。ST可导致多种并发症,CBCT的准确分析有助于ST的诊断和治疗。

Objective To analyze the radiographic characterizations of the supernumerary tooth(ST)in the anterior maxillary region using cone-beam computed tomography(CBCT),in order to help clinicians treat ST.Methods CBCT data of 805 patients were selected.The radiographic characterizations of the ST were evaluated using NNT software,including the number,morphology,location,orientation,growth condition and associated clinical complications.Gender differences of the radiographic characterizations were analysed.Results Male patients outnumbered females with a gender ratio of 2.96∶1.The majority of ST was single,conical shape,palatal,inverted orientation and impacted in both males and females,but the ratio of two ST in males was higher than that in females(P<0.001).Inverted orientation in females was higher than that in males(P<0.001).The most common ST-associated complication was bone resorption of the walls of the nasopalatine canal,and the ratio in males was higher than that in females(P=0.01).In addition,anatomical structures involved by ST and other complications also included bone resorption of nasal floor,odontogenic cyst formation,follicle gap of tooth widen,impaction,malposition,rotation and root resorption of adjacent teeth.Conclusion The majority of ST was single,conical shape,palatal,inverted orientation and impacted in both males and females,but the clinical characterizations between males and females showed significant difference.The presence of ST may produce several complications.The accurate analysis of CBCT scan assists the diagnosis and treatment of ST.