Objetives: This study evaluated the sealing capability of MTA when it is used as the only root canal filling material and when it is used as sealing cement combined with gutapercha points. Materials and methods: The mesial roots of 24 inferior molars were selected; they were instrumented until an apical master file # 40 with Crown Down technique. Group I were obtured with gutapercha points and MTA as sealing cement; group II were obtured only with MTA. Four roots were used as positive and negative control, samples were covered with sticky wax, leaving free the apical last 2 mm, they were centrifugued with chinese ink for one hour and then they were turned transparent, to measure the microleakage with a stereoscopic microscope. Results: Results were analyzed statistically with the KRUSKAL-WALLIS test for independent variables and statistically no significant difference was found between the two groups. Conclusion: Statistically no significant difference was found between the two groups. In such clinical situations that don't permit conventional obturation with gutapercha points, both MTA techniques are viable.