Mashyakhy M H, Chourasia H R, Jabali A H, Bajawi H A, Jamal H, Testarelli L, Gambarini G
Department of Restorative Dental Sciences, College of Dentistry, Jazan University, Jazan, Saudi Arabia.
General Dentist, Baish Hospital, Ministry of Health, Jazan, Saudi Arabia.
Niger J Clin Pract. 2020 Feb;23(2):232-239. doi: 10.4103/njcp.njcp_335_19.
To evaluate the prevalence, correlation, and differences of C-shaped canal morphology in mandibular premolars and molars by means of cone-beam computed tomography (CBCT).
A total of 1433 mandibular premolars and molars CBCT scans from the Saudi population were evaluated. Axial sections of the roots were acquired at coronal, middle, and apical levels to evaluate C-shaped canals types. The prevalence, correlation, differences of C-shaped canals, bilateral/unilateral presence, gender differences, and location of external grooves on roots were assessed.
The prevalence of C-shaped canals in the first premolars was 1.5%, 0.80% in second premolars and 7.9% in second molars, whereas C-shaped canals were absent in first molars. No correlation was found between the presence of C-shaped canals within premolars and molars and between the two groups in the same individual. Both premolars and molars exhibited different types of C-shaped canals, C2 being predominant in premolars and C3 in second molars. Longitudinal external grooves were mostly located on mesiolingual (ML) surface in premolars and lingual in molars. Females showed more prevalence of C-shaped canals in second molars and no differences in premolars. Bilateral symmetry and unilateral presence in premolars and second molars were not significant.
Although the prevalence of C-shaped canals is significantly higher in mandibular second molars, they are also found in mandibular premolars but in small percentages. No significant differences were found between both genders and both sides. Since they exhibit unpredictable morphology and differences across the root length, the use of small field CBCT is recommended when such anatomy is presented in a tooth indicated for root canal treatment for better management.
通过锥形束计算机断层扫描（CBCT）评估下颌前磨牙和磨牙C形根管形态的患病率、相关性及差异。
对来自沙特人群的1433例下颌前磨牙和磨牙的CBCT扫描进行评估。在冠部、中部和根尖水平获取牙根的轴向截面，以评估C形根管类型。评估C形根管的患病率、相关性、差异、双侧/单侧存在情况、性别差异以及牙根上外部沟的位置。
第一前磨牙中C形根管的患病率为1.5%，第二前磨牙为0.80%，第二磨牙为7.9%，而第一磨牙中不存在C形根管。在前磨牙和磨牙中C形根管的存在情况之间以及同一个体的两组之间均未发现相关性。前磨牙和磨牙均表现出不同类型的C形根管，前磨牙中C2型为主，第二磨牙中C3型为主。纵向外部沟在前磨牙中大多位于近中舌侧（ML）表面，在磨牙中位于舌侧。女性在第二磨牙中C形根管的患病率更高，在前磨牙中无差异。前磨牙和第二磨牙的双侧对称性和单侧存在情况均不显著。
尽管下颌第二磨牙中C形根管的患病率显著更高，但在下颌前磨牙中也有发现，不过比例较小。在性别和两侧之间均未发现显著差异。由于它们表现出不可预测的形态以及牙根长度上的差异，当在需要进行根管治疗的牙齿中出现这种解剖结构时，建议使用小视野CBCT以更好地进行处理。
