Fracture resistance of teeth instrumented by the Self-Adjusting File, ProTaper NEXT and WaveOne

AimThe present in-vitro study aimed to compare the fracture resistance of mandibular premolars, obturated after instrumentation by Self-Adjusting File (SAF), ProTaper NEXT (PTN) and WaveOne (WO).MethodSixty extracted mandibular premolars were decoronated to obtain the root length of 15 mm. The samples were divided into 4 experimental groups: Group 1 without instrumentation (control), Group 2 instrumented with SAF, Group 3 with PTN (X1 and X2) and Group 4 with WO (primary). Following instrumentation, the samples were obturated by cold lateral compaction technique using gutta-percha and AH Plus sealer. A week later, after the sealer was completely set, a vertical load was applied to the specimen's canal until fracture. Statistical analysis was performed.ResultsThe mean fracture load exhibited significant difference (p < 0.01) (One-way ANAOVA) between the groups. The Multiple Tukey post hoc tests revealed, the fracture resistance by group 1 showed no statistical difference when compared to group 2 and group 3 (p > 0.05), but a significant difference with group 4 (p < 0.01). Group 2 (SAF) presented a significantly higher fracture resistance when individually compared to group 3 and 4 (PTN and WO) (p < 0.01).ConclusionTeeth instrumented by SAF exhibited a better fracture resistance.