Influence of sealer placement technique on the quality of root canal filling by lateral compaction or single cone.

The aim of this study was to evaluate the influence of the sealer placement technique on the quality of root canal filling using Lateral Compaction (LC) or Single Cone (SC). In order to do that, 60 mesial roots of mandibular first molars were prepared and divided into 2 groups (n=30), according to the filling technique: LC and SC. Each group was subdivided into 3 subgroups (n=10), according to the different sealer placement methods: A: Master gutta-percha (GP) cone; B: Lentulo spiral; C: File. The roots were sectioned at 2, 4 and 6 mm from the apex and photographed with the aid of a digital microscope. Then, areas of GP, endodontic sealer and voids were measured, and these data were subjected to statistical analysis. LC technique showed no statistically difference (p>0.05) in the percentage of GP area, sealer and voids between the subgroups at any of the three levels. After use of SC, higher percentages of sealer area were found at all levels (p<0.01) when the sealer was placed with a file. At 2 mm, higher percentage of void areas (p<0.05) was observed when the cone was used, lower percentage with K-file and the lowest percentage with Lentulo. At 4 mm, cone showed higher percentage of void areas (p<0.05). At 6 mm, there were no significant differences (p>0.05) between the three methods. Considering these results, using an instrument for sealer placement was important in the SC technique to reduce voids. Regarding LC, the sealer placement techniques provided similar results.