Background and Aims: Root canal obturation is of great importance in root canal treatment. Its purpose is to eliminate microleakage, re-entry and growth of micro-organisms in the root canal system. The aim of this study was to compare coronal salivary microleakage in obturated root canals using lateral compaction, single cone gutta-percha and System B vertical compaction methods.

Materials and Methods: In this in-vitro study, 80 single rooted, human extracted teeth were randomly divided into 3 experimental groups (n=20) and 2 positive and negative control groups (n=10). The specimens in each experimental group were obturated by using cold lateral compaction, single cone obturation, or continuous wave of condensation (system B). After that, coronal saliva leakage was evaluated. Data were analyzed using Survival analysis and Log-rank test.

Results: The results showed that all the specimens in the positive control group showed evidences of leakage during the first 7 days of study. None of the specimens in negative control group showed leakage during the 30-days period of the experiment. Survival test and log-rank test showed that at the end of the 30 days, there was significantly less resistance to coronal salivary leakage in single cone method compared with lateral compaction (P=0.039) and continuous wave of condensation (P=0.019) groups. No significant difference was observed between lateral compaction and System B vertical continuous method (P=0.564).

Conclusion: Based on the results of this study, lateral compaction and system B groups showed higher resistance against the coronal leakage compared with single cone group.