School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China.
Department of Endodontics, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, Zhejiang Province, People's Republic of China.
BMC Oral Health. 2023 Sep 30;23(1):707. doi: 10.1186/s12903-023-03271-w.
The purpose of this study was to survey the prevalence of C-shaped root canal system in mandibular first premolar in Chinese population by reading Cone-beam computed tomography (CBCT) images and to analyze its anatomical characteristics by CBCT and Micro-computed tomography (Micro-CT).
The prevalence and the morphologic features of C-shaped root canal system were evaluated by observing CBCT images of 760 patients (1520 mandibular first premolars). 66 mandibular first premolars with C-shaped root canal system were scanned by Micro-CT. The morphologic features including radicular groove, C-shaped root canal categories in the cross-sections and in the 3D models, accessory and connecting canals, apical foramina and accessory foramina, were analyzed using image software.
C-shaped root canal system was identified in 16.9% of mandibular first premolars. The minimum mesial wall thickness most commonly occurred at the lingual site (69.7%). Regarding to the cross-sectional classification, the maximum was C2 (41.5%). In the 3D classification, the most common was S (34.8%). Accessory canals were observed in 36.4% of the samples and occurred mostly in the middle and apical regions. 42.4% samples had 1-3 variable connecting canals, and 40.9% samples had only one apical foramen.
The incidence of C-shaped root canal system in mandibular first premolars was 16.9% in the Chinese population. The anatomy was very complex and variable, mostly distributed in the middle and apical regions of the root canal. The mesial wall of C-shaped canal was extremely thin on the lingual side.
本研究通过阅读锥形束 CT（CBCT）图像，调查中国人群下颌第一前磨牙 C 型根管系统的发生率，并通过 CBCT 和微计算机断层扫描（Micro-CT）分析其解剖特征。
通过观察 760 名患者（1520 颗下颌第一前磨牙）的 CBCT 图像，评估 C 型根管系统的发生率和形态特征。对 66 颗具有 C 型根管系统的下颌第一前磨牙进行 Micro-CT 扫描。使用图像软件分析形态特征，包括根沟、横断面和 3D 模型中的 C 型根管分类、副根管和连接根管、根尖孔和副孔。
下颌第一前磨牙 C 型根管系统的发生率为 16.9%。最小近中壁厚度最常见于舌侧（69.7%）。在横断面分类中，C2 型（41.5%）最多见。在 3D 分类中，最常见的是 S 型（34.8%）。副根管在 36.4%的样本中观察到，主要发生在根管的中部和根尖区。42.4%的样本有 1-3 个可变连接根管，40.9%的样本只有一个根尖孔。
在中国人群中，下颌第一前磨牙 C 型根管系统的发生率为 16.9%。解剖结构非常复杂且多变，主要分布在根管的中部和根尖区。C 型根管的近中壁在舌侧非常薄。
