Objective To observe the therapeutic effect of one-time root canal therapy with vitapex paste in the treatment of pulpitis and chronic periapical periodontitis.Method 184 patients（190 diseased teeth） with pulpitis and chronic periapical periodontitis in our department of dentistry from 2006 to 2008 were randomly divided into experimental group with 93 cases（96 diseased teeth） and control group with 91 cases（94 diseased teeth）

and were treated with one-time root canal compaction with vitapex paste and with regular root canal compaction paste and lateral condensed gutta percha respectively.The clinical responses and therapeutic effect were observed one week and twelve months after the surgery respectively.Results One week after the surgery

89 diseased teeth in the experimental group felt no pains and 62 diseased teeth in the control group felt no pains

which accounted for 92.71% and 65.96% of each group respectively

and the differences were statistically significant（p<0.01）;Twelve months after the surgery

93 diseased teeth in the experimental group were cured with a success rate of 96.88% and 71 diseased teeth in the control group were cured with a success rate of 75.53%

and the differences were statistically significant（p<0.01）.Conclusion Vitapex paste has relatively good therapeutic effects in one-time root canal therapy for treating pulpitis and chronic periapical periodontitis and thus it is an ideal root canal sealer material for the one-time root canal therapy.