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Updated: Apr 10, 2026

Scanning Electron Microscopic Evaluation of Surface Defects of Remover Retreatment File After Single and Multiple Uses
Published on: October 11, 2024
Stereomicroscopic evaluation of dentinal defects induced by new rotary system: "ProTaper NEXT"
Deepa Deepak Shori1, Pratima Ramakrishna Shenoi1, Arshia R Baig1
1Department of Conservative Dentistry and Endodontics, Vidya Shikshan Prasarak Mandal's Dental College and Research Centre, Nagpur, Maharashtra, India.
Introduction:
The objective of this study was to evaluate dentinal defects formed by new rotary system - Protaper next™ (PTN).
Materials And Methods:
Sixty single-rooted premolars were selected. All specimens were decoronated and divided into four groups, each group having 15 specimens. Group I specimens were prepared by Hand K-files (Mani), Group II with ProTaper Universal (PT; Dentsply Maillefer), Group III with Hero Shaper (HS; Micro-Mega, Besancon, France), and Group IV with PTN (Dentsply Maillefer). Roots of each specimen were sectioned at 3, 6, and 9mm from the apex and were then viewed under a stereomicroscope to evaluate presence or absence of dentinal defects.
Results:
In roots prepared with hand files (HFs) showed lowest percentage of dentinal defects (6.7%); whereas in roots prepared with PT, HS, and PTN it was 40, 66.7, and 26.7%, respectively. There was significant difference between the HS group and the PTN group (P < 0.05).
Conclusion:
All rotary files induced defects in root dentin, whereas the hand instruments induced minimal defects.

