Effect of post space preparation on the sealing ability of mineral trioxide aggregate and Gutta-percha: A bacterial leakage study

AIM: The purpose of this study was to evaluate the effect of post space preparation on the sealing ability of teeth obturated with mineral trioxide aggregate (MTA) and Gutta-percha. MATERIALS AND METHODS: Fifty intact human mandibular premolars, after decoronation and biomechanical preparation, were randomly divided into three experimental groups. In Group A (n = 10), the canals were obturated with Gutta-percha using cold lateral compaction technique, followed by immediate post space preparation. In Group B (n = 10), the canals were obturated with 8 mm of MTA and in Group C (n = 10), sectional obturation with 4 mm of MTA was done, followed by delayed post space preparation. All specimens were subjected to bacterial leakage analysis, and the occurrence of turbidity was checked. RESULTS: All specimens in the lateral compaction group leaked. The mean number of days at which leakage was observed in Groups A, B and C were 18.5 days, 93.6 days and 95.5 days. CONCLUSIONS: MTA can be considered as an alternative to Gutta-percha as an apical third restorative material for teeth indicated for post and core, as it demonstrates better-sealing ability compared with Gutta-percha. Further, the removal of set MTA for post space preparation does not disrupt the integrity of the remaining apical MTA.