[A retrospective clinical analysis of endodontic treatment of maxillary first molars].

PURPOSE: To evaluate the effect of root canal therapy (RCT) of maxillary first molars and the relevant influential factors. METHODS: A total of 170 maxillary first molars undergoing endodontic treatment were retrospectively studied. 100 molars were treated with vertical compaction technique (VCT) using warm gutta- percha under dental operating microscope (DOM), while 70 molars with traditional lateral compaction technique (LCT) under naked eyes. All patients were asked to revisit 5 years later and 5-year success rate was evaluated. Reversion 3.0.2 software package was used to analyze the data. RESULTS: The immediate high quality rates of RCT of VCT and LCT were 91% and 75.7%, respectively, which has significant difference (P<0.05). After 5 years, VCT kept high quality rate of RCT, while the high quality rate of RCT with LCT dropped from 75.7% to 68.6%. The 5-year clinical success rates of RCT with VCT and LCT were 98% and 81.4%, respectively; which had significant difference (P<0.05). CONCLUSIONS: VCT has excellent clinical effect in RCT of maxillary first molars. The use of DOM can increase the detection rate of the second mesiobuccal canal (MB2).