QUALITY OF SINGLE CONE AND GUTTA CORE OBTURATION IN CURVED ROOT CANALS AFTER NEEDLE OR DIODE LASER IRRIGANT ACTIVATION USING CONE BEAM COMPUTED TOMOGRAPHY AND STEREOMICROSCOPE

Objective: The purpose of this study was to assess the quality of single cone and gutta core obturation in curved root canals of the mandibular molars after needle and diode laser activation of both ethylenediaminetetraacidic acid (EDTA) and sodium hypochlorite (NaOCl) irrigation using cone beam computed tomography (CBCT) and stereomicroscope.
Methods: A total of twenty –four extracted human mandibular molars with root canal curvature more than 20 degrees and type IV anatomic configuration in the mesial roots were selected for this study. Canals in mesial roots were prepared with ProTaper next instruments up to x3 and equally divided into two experimental groups (n=12) according to final one minute activation for each of 5 ml 2.5% NaOCl and 5 ml 15% EDTA using; side-vented needle (group1) or 980 nm diode laser (group2). After preparation, the mesial canals were randomly obturated with either single-cone gutta-percha (sub group A) or gutta core Obturator (subgroup B). Obturated canals were scanned with cone beam computed tomography; images were used to assess the quality of obturation at different canals levels.  The roots were subsequently sectioned at 2, 4, 6, 8 and 12 mm levels from the apex for analyses of the percentage of gutta percha filled area (PGFA) and percentage of sealer filled area (PSFA) using stereomicroscope to examine the root sections. The areas of gutta percha and sealer for each segment of the root were measured using Image J software. Kruskal-Wallis test was used to analyze data.
 
Results: Both cone beam and digital stereomicroscopic data indicated that canals obturated with gutta core after irrigant activation had the highest PGFA. The Gutta core and diode laser acti- vation group produced significantly higher PGFA and lower PSFA at different root canal levels 4,6 and 8 mm levels of the root canal (P < .05) than all other groups at the same levels (P < .05). Single cone and EDTA has the lowest PGFA and highest PSFA (P < .05).
 
Conclusions: The results reinforced that 980-nm Diode activated irrigation improved the qual- ity of obturation of the mesial root canals in mandibular molars by using gutta core or single cone. Variation in root canal obturation technique and irrigation activation influenced the percentage of gutta percha filled area and percentage of sealer filled area.