下颌第二磨牙C形根管的特点和临床治疗

目的探讨下颌第二磨牙C形根管的发生率、临床诊断和治疗方法。方法通过对152例下颌第二磨牙拍摄术前X线片和术中根管探查,按照Melton标准诊断C形根管;采用机用镍钛器械Hero642进行根管预备,次氯酸钠超声冲洗,热牙胶垂直加压技术充填根管。记录C形根管的发生率及临床特点,根据治疗前、中、后的X线片评价根管预备和充填的效果。结果下颌第二磨牙C形根管的发生率为32.2%,79.6%的C形根管患牙X线片表现为锥形融合牙根,20.4%表现为近、远中独立牙根;所有患牙均无根管内并发症发生,治疗效果好。结论下颌第二磨牙C形根管主要存在于融合牙根,根管探查结合X线片可诊断C形根管;机用镍钛器械预备根管、次氯酸钠超声冲洗和垂直加压技术充填根管可获得良好的治疗效果。

Clinical diagnosis and treatment of C-shaped root canals in mandibular second molars

Objective To discuss the incidence, diagnosis, and treatment of C-shaped root canals in mandibular second molars.Methods The C-shaped root canals in 152 mandibular second molars were diagnosed by X-ray films and canal exploration using Melton's method. The root canals were shaped by using Ni-Ti rotary instruments Hero 642,cleaned by using ultrasonic irrigation with sodium hypochlorite, and obturated with vertical condensation technique for C-shaped root canals. The efficiency of preparation and obturation was analyzed with radiographs before, during and after operation. The prognosis was evaluated by patients' signs, clinical examination, and recall radiographs.Results The frequency of C-shaped canals in mandibular second molars was 32.2%. According to the X-ray films, 79.6% of teeth with C-shaped canals had fused roots, and 20.4% of C-shaped canals teeth revealed the distinct mesial and distal roots. There was no any complication in all cases. The result of treatment was good.Conclusion The C-shaped canal system in mandibular second molars has the radiograph image showing a fused root or distinct mesial and distal roots, which could be diagnosed by X-ray films and canals exploration. The C-shaped mandibular second molars can be treated very well with rotary instrumentation, ultrasonic irrigation with sodium hypochlorite, and vertical condensation technique.