Mashyakhy Mohammed
Department of Restorative Dental Sciences, College of Dentistry, Jazan University, Kingdom of Saudi Arabia, Phone: +966 557224154, e-mail:
J Contemp Dent Pract. 2019 Jul 1;20(7):773-777.
This study evaluated the prevalence of a second root and canal, gender differences, and bilateral symmetry of mandibular and maxillary permanent canines in a Saudi Arabian population using a cone-beam computed tomography (CBCT).
The first step was to evaluate CBCT images of 208 patients with 794 canines (410 mandibular and 384 maxillary canines). The second step was to identify the number of roots, number of canals, and canal configurations based on Vertucci's classification to investigate the prevalence of a second root and a second canal, gender differences, and bilateral symmetry. A test evaluated differences in the independent proportions; a Chi-square test determined differences between genders and Cohen's Kappa test assessed bilateral symmetry.
The prevalence of two roots and two canals in mandibular canines was 2.7% and 9.3%, respectively, and Vertucci's type III appeared in 6.1%, and Vertucci's type V appeared in 3.2%. In maxillary canines, there were no two-rooted teeth, and only 1% of two canals were present with Vertucci's type III. There were no statistically significant differences between genders in both mandibular and maxillary canines. High bilateral symmetries of roots and canals appeared in mandibular canines (95.5% and 91.1%, respectively) and maxillary canines (100% and 98.9%, respectively).
One root, one canal, and Vertucci's type I are the primary and typical characteristics of mandibular and maxillary canines. The presence of a second root in mandibular canines is small, although the presence of two canals is not unusual. Conversely, it is rare to find a second root and canal in maxillary canines.
Mandibular canines showed bilateral asymmetry (8.9%) in the number of canals between the right and left sides, which could be of clinical importance when planning root canal treatment (RCT) on contralateral canines.
本研究使用锥形束计算机断层扫描（CBCT）评估沙特阿拉伯人群下颌和上颌恒牙尖牙第二根和根管的患病率、性别差异以及双侧对称性。
第一步是评估208例患者的CBCT图像，其中有794颗尖牙（410颗下颌尖牙和384颗上颌尖牙）。第二步是根据韦尔图奇分类法确定牙根数量、根管数量和根管形态，以研究第二根和第二根管的患病率、性别差异以及双侧对称性。t检验评估独立比例的差异；卡方检验确定性别差异，科恩kappa检验评估双侧对称性。
下颌尖牙两根和两个根管的患病率分别为2.7%和9.3%，韦尔图奇III型出现率为6.1%，韦尔图奇V型出现率为3.2%。在上颌尖牙中，没有双根牙，只有1%的两个根管为韦尔图奇III型。下颌和上颌尖牙的性别之间均无统计学显著差异。下颌尖牙（分别为95.5%和91.1%）和上颌尖牙（分别为100%和98.9%）的牙根和根管呈现高度双侧对称性。
一根、一个根管和韦尔图奇I型是下颌和上颌尖牙的主要和典型特征。下颌尖牙中第二根的出现率较低，尽管两个根管的情况并不罕见。相反，上颌尖牙中发现第二根和根管的情况很少见。
下颌尖牙左右两侧根管数量显示出双侧不对称（8.9%），这在对侧尖牙进行根管治疗（RCT）规划时可能具有临床重要性。
