Comparative evaluation of pericervical dentin preservation and fracture resistance of root canal-treated teeth with rotary endodontic file systems of different types of taper - An in vitro study.

Abstract

The aim of this study was to evaluate and compare the pericervical dentin preservation and fracture resistance of root canal-treated teeth with rotary endodontic file systems of different types of taper. Thirty-two single-rooted human-extracted premolars were used. They were mounted in wax, and preoperative cone-beam computed tomography (CBCT) scans were taken with 11 × 8 Field of view (FOV). The evaluation of the pericervical dentin thickness was done at the cementoenamel junction level. After pre-CBCT, the 32 samples were divided into four groups (n = 8) - Group A: fixed tapered hand files, Group B: variable regressive tapered TruNatomy, Group C: progressive tapered ProTaper Gold, and Group D: fixed tapered HyFlex EDM. Following instrumentation, postoperative CBCT scans were taken to evaluate pericervical dentin thickness. Obturation was done and access cavity was restored with composite. Fracture strength was checked for all the samples using "universal testing machine" until fracture, and calculated in newtons (N). Student's t-test and ANOVA test, along with Tukey's post hoc analysis, were used for comparing mean values between the groups, and P < 0.05 was considered statistically significant. The results of this study showed that there is no statistically significant difference in preserving pericervical dentin with file system of different types of taper and fracture resistance between the groups. Within the limitations of the study, it was concluded that different types of file taper systems used for root canal preparation have no significant effect on the preservation of pericervical dentin and fracture resistance of teeth.