根管阻塞的临床研究

目的：总结根管阻塞的主要原因及影响阻塞根管疏通的主要因素。方法：收集病例89例，共107个根管阻塞，在显微镜下使用超声器械和小号手用器械进行根管疏通。记录根管阻塞的情况和效果。结果：根管阻塞的原因主要有根管治疗史及钙化等。磨牙的根管较前牙及前磨牙易发生阻塞，且疏通成功率较低。因牙胶充填、塑化、钙化和其他原因导致的根管阻塞疏通的成功率依次为85％、52．8％、69．7％和55．6％。在X线片上有根管影像的阻塞根管疏通成功率（75．3％）高于无根管影像者（47．6％）（P〈0．05）。根管上段阻塞的疏通成功率明显高于根管下段阻塞者（P〈0．05）。结论：塑化和钙化是较常见的导致根管阻塞的主要因素，塑化根管阻塞的再通成功率不高，根管阻塞的位置和牙位影响疏通成功率。

The clinic research of canal blockage.

Objective： To summarize the main etiology of canal blockage and the main contributing factors of successful negotiation through treating and analyzing the clinical cases with blocked root canals. Method： 89 patients with 107 blocked root canals were involved. All the canals were negotiated by using ultrasonic technique and small size hand files under dental operating microscope, The root canal blockage and negotiation results were recorded. Result： The common eti- ology of canal blockage included root canal treatment history, calcifications and other factors. The blocked canals were more often occurred in the molars than in anterior teeth and premolars, and the success rate of blocked canals being managed was lower in the molars. The success rate of each category of the blocked canals was： 85 % for canals filled with gutta-percha, 52.8 % for canals subjected to resinifying therapy, 69.7 % for calcified root canals, and 55.6 % for blocked canals caused by other factors. Canals showed on radiograph clearly had a success rate of 75.3 %, whereas those that were not visible on the X-ray film had a significantly lower success rate of 47.6 % （P 〈0.05）. The success rate of blocked canals at the coronal third is higher than that at the apical third （P 〈0.05）. Conclusion： Resinifying therapy and calcification are the main factors resulting in blocked canals. Blocked canals caused by resinifying therapy were managed with the lower success rate. The blockage locations in canals and the teeth positions influence the success rate of blocked canal therapy.