下颌第二磨牙C形根管诊断与治疗探讨

目的 探讨下颌第二磨牙C形根管的发生率、临床诊断和方法.方法 通过对130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,用"拉网法"进行根管设备,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线光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26.9%.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;所有惠牙均无根管内并发症发生,治疗效果理想.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;采用机用镍钛器械,"拉网法"进行根管预备,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 130 cases of 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 and using the so-called drawing-fish-net'root canal preparation technique,cleaned by using ultrasonic irrigation with sodium hypochorite,and obturated with vertical condensation technique for C-shaped root canals.The efficiency of preparation and obturation was analyzed with radiographs before,during and afer operation.The prognosis was evaluated by patients'signs,clnical examination,and recall radiographs.Results The frequency of C-shaped canals in mandibular second molars was 26.9%.According to the X-ray films,79.6% of teech with C-shaped canals had fused roots,and 20.4% of C-shaped canals teech 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,the so-called drawing-fishnet's root canal preparation technique,ultrasonic irrigation with sodium hypochlorite,and vertical condensation technique.