Under the conditions of these in vitro leakage studies , it is concluded that smear layer removal improves the fluid-tight seal of the root canal system whereas other factors such as the obturation technique or the sealer , did not produce significant effects
The purpose of this systematic review was to determine whether smear layer removal reduces leakage of obturated human teeth in vitro .
Coronal leakage following three obturation techniques.
AIM To compare coronal bacterial and India ink leakage in three different obturation techniques with the smear layer having been removed . METHODOLOGY Seventy extracted single-rooted teeth were instrumented to an apical preparation size 7 Profile Series 29 ( Tulsa Dental Products , Tulsa , OK , USA ) . The smear layer was removed and 20 teeth were r and omly obturated with lateral compaction , 20 teeth with vertical compaction , and 20 teeth with Thermafil ( Tulsa Dental Products , Tulsa OK , USA ) . Ten teeth were used for positive ( five teeth ) and negative ( five teeth ) controls . Teeth were stored for 90 days in 100 % humidity , then subjected coronally to Proteus vulgaris for 21 days to assess bacterial leakage . Following bacterial challenge , India ink was placed coronally for a further 21 days , then scored according to depth of dye leakage . RESULTS  Vertical compaction leaked significantly less than lateral compaction during bacterial challenge . However , when dye was used there were no significant differences . CONCLUSIONS Bacterial leakage and dye leakage demonstrated considerable variability . The use of a dye following bacterial testing may highlight the failure of experimental devices and vertical root fractures , thus avoiding false positive results found with bacterial testing alone
Under the conditions of these in vitro leakage studies , it is concluded that smear layer removal improves the fluid-tight seal of the root canal system whereas other factors such as the obturation technique or the sealer , did not produce significant effects
The purpose of this systematic review was to determine whether smear layer removal reduces leakage of obturated human teeth in vitro .