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 .
Adaptation and sealability of two contemporary obturation techniques in the absence of the dentinal smear layer.
AIM The aim of this study was to evaluate the adaptation and short- and long-term sealability of two different thermoplastic techniques -- a core carrier technique , Thermafil ; and a warm vertical continuous wave of compaction technique , System B. METHODOLOGY Fifty-one mesial roots of m and ibular molars with separate canals , patent canal orifices and curvature greater than 15 degrees were cleaned and shaped with Orifice Shapers and ProFile.04/.06 taper Ni-Ti rotary files using 5.25 % NaOCl and 17 % REDTA to a size 30.04 taper Profile at the apex to create a continuous tapered preparation . Canals were r and omly obturated with Sealapex root canal sealer and either alpha-phase gutta-percha on a plastic Thermafil carrier , or nonst and ardized beta-phase gutta-percha using the System B heat source . Proximal radiographs of roots were evaluated by three examiners based on established criteria for overall material adaptation , apical adaptation and filling material extrusion . Teeth were r and omly separated into three groups of 17 each and placed in black India ink for 10 days , 24 h , or after 67 days storage in Hank 's Balanced Salt Solution . All roots were demineralized and rendered transparent . Three examiners evaluated the apical leakage by the linear measurement of dye penetration under the stereo-microscope . The movement of filling material into canal irregularities was also evaluated . RESULTS Both obturation techniques were not significantly different in the overall canal obturation and in the apical third adaptation ( P > 0.05 ) . Significantly more filling material extrusion beyond the apex was noted with the Thermafil technique ( P < 0.001 ) . No significant difference was found amongst the 67-day , 10-day and 24 h System B groups ( P > 0.05 ) . The 67-day Thermafil group showed significantly more leakage than the 10-day and 24 h Thermafil groups . There was a significant difference in the degree of leakage between the 67-day Thermafil group and the 67-day System B group ( P < 0.05 ) , but not between the 10-day and 24 h groups ( P > 0.05 ) . Both obturation techniques produced substantial filling material movement into canal irregularities . CONCLUSIONS It was concluded that Thermafil demonstrated more filling material extrusion beyond the apex and significantly more long-term apical leakage
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 .