The effect of Resilon system on the fracture resistance of endodontically treated roots using two instrumentation techniques : an in vitro study

الملخص EN

Background : vertical Root Fracture (VRF) is one of the most common problems facing endodontic ally treated teeth.

The greatest incidence of VRF occurs in teeth that have undergone endodontic therapy.

The aim of this study was to evaluate the fracture resistance of endodontic ally treated roots using two instrumentation techniques either rotary with ProTaper system or hand instrumentation with k-files and obturated with different obturation techniques: Guttapercha with ZOE.

Sealer, Gutta-percha with AH-26 sealer or Resilon cones with Real-Seal sealer.

Materials and Methodology: Ninety root samples were sectioned, from natural mandibular premolar teeth freshly extracted for various reasons and stored in sterile water, to a length of 14 mm, and then the samples were randomly divided into 9 groups with ten roots for each group.

Group I: Uninstrumented-unfilled roots, (control group) Group II : Hand instrumentation-GP+Z.O.E.

sealer obturation.

Group III : Hand instrumentation-GP+AH-26 sealer.

Group IV : Hand instrumentation-Resilon+Real-Seal sealer.

Group V: Hand instrumentation-No obturation.

Group VI: Rotary instrumentation-GP+Z.O.E.

sealer.

Group VII: Rotary instrumentation-GP+AH-26 sealer.

Group VIII: Rotary instrumentation-Resilon+Real-Seal sealer.

Group IX : Rotary instrumentation-No obturation.

The samples were incubated in 37 c and 100% humidity for 7 days, and then they were subjected to the mechanical test in a universal testing machine and the maximum load at the fracture point for each sample was recorded.

Results : Descriptive statistics showed higher means of fracture loads for Resilon groups and student t-test showed a significant difference between Resilon group over other experimental groups for rotary instrumented roots, for hand instrumented roots there was no significant difference between different obturation techniques.

Rotary ProTaper instrumented roots were significantly less than hand instrumented roots in resistance to fracture.

Conclusion : rotary instrumentation with ProTaper instruments significantly decreased fracture resistance of teeth and Resilon system significantly increased resistance to fracture more than other obturation materials used in this study.