应用锥形束CT对成人上颌前磨牙牙根和根管系统形态的研究

Study of Root and Root Canal Morphology of Maxillary Premolars Evaluated By Cone Beam Computed Tomography

目的:运用锥形束CT(CBCT)观察中国人群上颌前磨牙的牙根和根管系统的解剖形态,为临床根管治疗提供影像学依据。方法:选择200名患者的双侧上颌前磨牙(上颌第一前磨牙、上颌第二前磨牙各358颗)的CBCT扫描数据,使用NNT软件分析上颌第一、第二前磨牙的牙根数、根管数、根管分型以及双侧对称情况。结果:上颌第一前磨牙主要为单根(65.92%)和双根(33.80%)。上颌第二前磨牙主要为单根(93.85%)。上颌第一前磨牙的根管系统主要为双根管(84.36%)。上颌第二前磨牙的根管系统单、双根管比例接近(分别为52.79%和46.08%)。上颌第一前磨牙主要根管分型为:Ⅳ型(48.32%)、Ⅱ型(24.30%)和Ⅰ型(12.56%)。上颌第二前磨牙主要根管分型为:Ⅰ型(51.68%)、Ⅱ型(21.51%)和Ⅳ型(14.25%)。上颌第一、第二前磨牙的根管分型左右对称(对称率分别为74.57%和81.29%)。上颌前磨牙根管系统的主要变异为:管间交通支、颊根C形根管和多根管(树形根管或神经根样根管)。结论:上颌第一、第二前磨牙的根管系统主要为单根管和双根管。术前了解根管形态的变异是治疗成功的关键因素。

Objective： To investigate variations in root canal configuration of the maxillary first and second premolar teeth using cone-beam computed tomography （CBCT）. Methods： A total of 200 patients with healthy ,untreated ,well-developed maxillary first and second premolars were envolled. Radiographic examined by CBCT was conducted as part of their routine examination. Over all, 358 maxillary first premolars and second premolars with same number were examined in vivo by CBCT. The number of roots, the number of canals per root ,the canal configuration and symmetry of bilateral canal classification were record. Results： 65.92 %of maxillary first premolar teeth had one root and 33.80%had two roots. 93.85% of maxillary second premolar teeth had one root. Most of maxillary first premolars（84. 36%）had two canals, the most frequent canal configuration of these teeth was type IV （48. 32%） ,followed by type Ⅳ[ （24.3%） ,with 12.56% of teeth having type Ⅰ. 51.68% maxillary second premolars had one canal and 46.08% had two canals. The most frequent canal configuration was type Ⅰ（51.68%）,followed by type Ⅱ （21.58%） and type Ⅳ （14.25%）,74.57% maxillary first premolars and 81.29% second premolars had bilateral canal symmetry in configurations. There were some other anatomic variation in root canal system such as ： intercanal communications ,＂ ridiculous＂ premolar , and C-shaped canal in buccal roots were also identified. Conclusion： There was a high frequency of one or two root canals in maxillary first and second premolars. Clinacians should be aware of the different variations in root morphology and canal configuration when performing an endodontic treatment.