Fracture resistance of roots using different canal filling systems

P>Aim To evaluate the fracture resistance of teeth filled with various canal filling materials. Methodology The crowns of 100 single-rooted teeth were removed leaving 12 mm of the roots. The canals were shaped using Endo-Sequence files. Following instrumentation, 80 teeth were divided into four groups. The remaining 20 teeth were divided into two groups. The teeth in each group were filled as follows: Group 1: AH-Plus + Gutta-percha (Cold lateral compaction), Group 2: Resilon + Epiphany (Cold lateral compaction), Group 3: ActiV GP cone + ActiV GP sealer, Group 4: ActiV GP sealer + Gutta-percha (Cold lateral compaction), Group 5: No instrumentation or filling, Group 6: Instrumentation but no filling. After the sealers had set, the roots were embedded in acrylic moulds and subjected to a compressive loading at a rate of 1 mm min(-1). The load at which fracture occurred was recorded and statistically analysed using Kruskal-Wallis one-way analysis of variance and Z-tests. Results The fracture values of the experimental teeth were significantly higher than those of the instrumented but unfilled group (P < 0.05). Teeth in the AH-Plus + lateral compaction group had higher fracture resistance compared with the ActiV GP sealer + Gutta-percha group (P < 0.05). Conclusions Systems aiming to obtain a monoblock system were not superior to the conventional AH-Plus + Gutta-percha technique in terms of fracture resistance. The fracture resistance of roots using ActiV GP + lateral compaction Gutta-percha was significantly reduced compared with the AH-Plus + Gutta-percha group.