Liu Ya-Jing, Liu Shu, Liu Ting, Zhang Jun, Zhu Ya-Nan
Department of Endodontics, Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
Department of Dentomaxillofacial Radiology, Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China.
Arch Oral Biol. 2023 Nov;155:105781. doi: 10.1016/j.archoralbio.2023.105781. Epub 2023 Aug 5.
This retrospective study aims to analyze the root canal morphology of permanent mandibular incisors and the bifurcating/merging sites of root canal systems in children aged 9-12 in a Chinese subpopulation.Design Cone-beam computed tomography scans of 976 healthy, untreated and fully developed mandibular incisors were collected. Root canal morphology was identified by Vertucci's classification. Combined three-dimensional reconstruction and visualization techniques were used to locate bifurcating/merging sites in root canals.
Vertucci I was the most common classification of mandibular central incisors (42.3%) while Vertucci III was most common in mandibular lateral incisors (37.9%). Females more frequently showed Vertucci I classification (49.5% central incisors and 36.7% lateral incisors) while Vertucci III was most common among males (44.5% central incisors and 41.0% lateral incisors). The difference in canal classification by sex was statistically significant (p < 0.05). 58.7% of Vertucci V canals bifurcated in the apical third (AT) in central incisors, while 69.5% bifurcated in the middle third (MT) in lateral incisors. Bifurcating and merging in AT (44.3%) was the most common style of Vertucci III canals in central incisors, while bifurcating in MT and merging in AT (53.8%) was the most common in lateral incisors.
The root canal morphology of mandibular incisors in children aged 9-12 was different from that reported in previous studies on adults, and closely related to sex. Males had significantly greater canal variability than females. Lateral incisors had greater canal variability than central incisors. The bifurcating/merging sites were closely related to tooth type.
本回顾性研究旨在分析中国9至12岁儿童恒牙下颌切牙的根管形态及根管系统的分叉/融合部位。设计收集976颗健康、未经治疗且发育完全的下颌切牙的锥形束计算机断层扫描图像。采用Vertucci分类法确定根管形态。运用三维重建和可视化技术相结合的方法来定位根管中的分叉/融合部位。
Vertucci I型是下颌中切牙最常见的分类（42.3%），而Vertucci III型在下颌侧切牙中最为常见（37.9%）。女性更常表现为Vertucci I型分类（中切牙为49.5%，侧切牙为36.7%），而Vertucci III型在男性中最为常见（中切牙为44.5%，侧切牙为41.0%）。根管分类在性别上的差异具有统计学意义（p < 0.05）。58.7%的Vertucci V型根管在中切牙的根尖三分之一处（AT）分叉，而69.5%的根管在侧切牙的根中三分之一处（MT）分叉。中切牙中，Vertucci III型根管在AT处分叉并融合（44.3%）是最常见的类型，而侧切牙中，在MT处分叉并在AT处融合（53.8%）是最常见的类型。
9至12岁儿童下颌切牙的根管形态与先前关于成人的研究报道不同，且与性别密切相关。男性的根管变异明显大于女性。侧切牙的根管变异大于中切牙。分叉/融合部位与牙齿类型密切相关。
