Mohammad N, Omar S H, Ravindran S, Muhamad A Z, Mohd Desa Snf, Al-Kadhim Aha
Department of Conservative Dentistry and Prosthodontics, Faculty of Dentistry, Universiti Sains Islam Malaysia, Malaysia.
Department of Periodontology and Community Oral Health, Universiti Sains Islam Malaysia, Malaysia.
Niger J Clin Pract. 2025 Sep 1;28(9):1066-1075. doi: 10.4103/njcp.njcp_114_25. Epub 2025 Sep 27.
C-shaped canals are a complex root canal variation, most frequently observed in mandibular second molars. Their atypical anatomy can make root canal treatment more difficult and may lead to complications if not properly identified. The use of Cone Beam Computed Tomography (CBCT) offers superior visualisation of canals morphology compared to conventional radiography. While the prevalence of C-shaped canals has been reported in various populations, there is limited data regarding their prevalence and configuration in the Malaysian's multiracial population. Understanding these morphological variations is essential for treatment planning and improving clinical outcomes.
This cone beam computed tomography (CBCT) study aimed to determine the prevalence and configuration of C-shaped canals in permanent mandibular and maxillary second molars among the Malaysian population using the Modified Melton's classification.
A total of 274 CBCT images involving 605 second maxillary (n = 269) and second mandibular molars (n = 336) were obtained from Oral Radiology Unit, Faculty of Dentistry, Universiti Sains Islam Malaysia. For each tooth, the canal configurations were evaluated at three different levels: 'coronal', 'middle', and 'apical'. The canal configurations were subsequently classified according to the Modified Melton's classification. The prevalence and canal configuration correlation between sex, ethnicities, and tooth positioning were determined using odds ratio (P = 0.05).
The patients' ages ranged from 12 to 72 years old, with a mean age of 29.47 ± 11.53 years. The patients were female (76.6%) with Malays or Bumiputera (78.8%) predominance. The prevalence of C-shaped canals found was 10.1% (n = 44), and all were presented in second mandibular teeth. The most frequent C-shaped canals configuration found was C3-C3-C3 (29.5%). C-shaped canals were presented more likely when the patient is Chinese than other ethnicities with an odds ratio of 3.18 (95% CI, 1.562-6.488; P = 0.001) and in fused roots than multirooted roots (OR = 173.43; 95% CI, 65.077-462.195; P < 0.001). Sex was not associated with the prevalence of C-shaped canals in this study.
The prevalence of C-shaped canals of the mandibular second molar in the Malaysian subpopulation in this study was 10.1% with the most frequent configuration of C3-C3-C3 at 29.5%. The Chinese ethnicities and tooth with fused roots were more frequently associated with the incidence of C-shaped canals. Identification of the C-shaped canal morphology allows the clinician to modify the canal preparation and obturation techniques to obtain a good endodontic treatment outcome, while also preventing any iatrogenic or procedural errors.
C形根管是一种复杂的根管变异，最常见于下颌第二磨牙。其非典型的解剖结构会使根管治疗更加困难，如果未正确识别可能会导致并发症。与传统放射成像相比，锥形束计算机断层扫描（CBCT）能更好地显示根管形态。虽然不同人群中C形根管的发生率已有报道，但关于马来西亚多民族人群中其发生率和形态的数据有限。了解这些形态变异对于治疗计划和改善临床结果至关重要。
这项锥形束计算机断层扫描（CBCT）研究旨在使用改良的梅尔顿分类法确定马来西亚人群中恒牙下颌和上颌第二磨牙C形根管的发生率和形态。
从马来西亚伊斯兰理科大学牙科学院口腔放射科获取了总共274张CBCT图像，涉及上颌第二磨牙（n = 269）和下颌第二磨牙（n = 336）。对于每颗牙齿，在三个不同水平评估根管形态：“冠部”、“中部”和“根尖部”。随后根据改良的梅尔顿分类法对根管形态进行分类。使用优势比确定性别、种族和牙齿位置之间的发生率和根管形态相关性（P = 0.05）。
患者年龄在12至72岁之间，平均年龄为29.47±11.53岁。患者以女性为主（76.6%），马来人或原住民占多数（78.8%）。发现C形根管的发生率为10.1%（n = 44），且均出现在下颌第二磨牙中。最常见的C形根管形态为C3 - C3 - C3（29.5%）。与其他种族相比，华裔患者出现C形根管的可能性更大，优势比为3.18（95%可信区间，1.562 - 6.488；P = 0.001），融合根牙齿比多根牙齿更易出现C形根管（优势比 = 173.43；95%可信区间，65.077 - 462.195；P < 0.001）。在本研究中，性别与C形根管的发生率无关。
本研究中马来西亚亚人群下颌第二磨牙C形根管的发生率为10.1%，最常见的形态为C3 - C3 - C3，占29.5%。华裔和融合根牙齿与C形根管的发生率更相关。识别C形根管形态可使临床医生调整根管预备和充填技术，以获得良好的根管治疗效果，同时也能防止任何医源性或操作失误。
