不同器械预备根管对隐裂性牙髓炎临床治疗效果的影响

目的　探讨使用不同器械预备根管对隐裂性牙髓炎临床治疗效果的影响，为临床选择根备器械治疗隐裂性牙髓炎提供参考。方法：将60颗患有隐裂性牙髓炎的双根管型上颌第一前磨牙随机分为3组，Protaper组、MTwo组、K锉组，每组各20颗，分别用相应器械进行根备，其根管治疗步骤均相同。分别观察患牙根管治疗约诊间痛、术后3月治疗效果及1.5年内牙根纵裂发生率，并用卡方检验进行统计学分析。结果：K file组的根管治疗约诊间痛发生率（50.00%）明显高于Protaper组（10.00%，χ2=7.657，P=0.022）和MTwo组（15.00%，χ2=7.958，P=0.019），而Protaper组和MTwo组之间无统计学差异（χ2=2.029，P=0.363）。此外，近期治疗效果（χ2=1.966，P=0.742）、牙根纵裂（χ2=0.000，P=1.000）均与根备器械无明显相关性。结论：机用镍钛器械相比不锈钢K锉，可以明显降低根管治疗约诊间痛的发生率，近期具有良好的治疗效果，而且不会明显增加牙根纵裂的风险。

Influence of root canal preparation by different instruments on the therapeutic effect of pulpitis caused by hidden cracks

Objective To explore the clinical efficacy of pulpitis caused by hidden cracks using different root canal preparation instruments and provide clinical reference for choosing the instruments. Methods 60 two-root-canal 1st premolars with pulpitis caused by hidden cracks were randomly divided into three groups: the Protaper group, the MTwo group and the K File group, each with 20 teeth. The teeth in different groups were treated with different root canal preparation instruments and the other root canal treatment steps were the same. Endodontic interappointment pain, postoperative treatment effect in 3 months and the occurrence of vertical root fracture in 1.5 years were observed and analyzed by chi-square test. Results The occurrence rate of endodontic interappointment pain of K file group(50.00%) was significantly higher than that of Protaper group(10.00%,χ^2=7.657, P=0.022)and MTwo group(15.00%,χ^2=7.958, P=0.019), while there was no significant difference between Protaper group and MTwo group(χ^2=2.029, P=0.363). Moreover, there was no significant correlation between root canal preparation method and short-term treatment effect(χ^2=1.966, P=0.742)or occurrence of vertical root fracture in 1.5 year(χ^2=0.000, P=1.000). Conclusion Compared with K file, rotary NiTi instruments can significantly reduce the occurrence rate of endodontic interappointment pain, have good therapeutic effect and do not significantly increase the risk of vertical root fracture.