锥形束CT在下颌第二磨牙C形根管系统应用的研究

目的　采用锥形束CT（简称CBCT）研究下颌第二磨牙C形根管的解剖形态，为根管治疗提供更加直观的影像学依据。方法　使用CBCT观察441例患者双侧下颌第二磨牙，统计C形根管的发生率以及根管形态。结果　C形根管的发生率为41.72%，C形根管类型变化多样，C形根管的发生率在性别、年龄间无统计学差异。结论　C形根管在下颌第二磨牙有很高的发生率，并且解剖形态有较大差异，CBCT在诊断C形根管方面具有重要作用。

Study on application of cone-beam computed tomography in C-shaped root canal system in mandibular second molars

Objective To evaluate the anatomical structure of C-shaped canal systems in mandibular second molars by cone-beam computed tomography（CBCT） and to provide more intuitive imaging foundations for canal treatment.Methods The mandibular second molars of 441 patients were observed by CBCT.The incidence of the C-shaped canals in mandibular second molars and the anatomical features of the C-shaped canal systems were analyzed.Results C-shaped canal system was present in 41.72% of the mandibular second molars.This prevalence did not vary in gender or age.The patterns of C-shaped canals varied a lot.Conclusions The incidence of the C-shaped canals of the mandibular second molars is high.The C-shaped canals vary greatly in their anatomical configurations.Besides,CBCT is of great significance for the diagnosis and treatment of C-shaped canal systems.