Assessment of the fracture resistance of teeth instrumented using 2 rotary and 2 reciprocating files versus the Self-Adjusting File (SAF): An ex vivo comparative study on mandibular premolars.
OBJECTIVE
Current ex vivo study compared fracture resistance of teeth instrumented using 5 endodontic files, filled with Gutta-percha and AH Plus.


METHODS
Sixty freshly extracted, single-rooted mandibular premolars were acquired and decoronated to obtain 15 mm segments. These samples were randomly divided into six groups (n = 10). Group 1 served as the control containing untreated samples (without instrumentation or filling). In Groups 2-6, samples were instrumented using rotary (Universal ProTaper and Revo-S), reciprocating (WaveOne and RECIPROC(®)), and self-adjusting file (SAF), respectively. Following instrumentation, the samples were filled by lateral compaction with Gutta-percha and AH Plus. A week later, after the sealer was completely set, a vertical load was applied to the specimen's canal in each group until fracture. The loads required for fracture were recorded, and statistical analysis was performed.


RESULTS
The mean fracture load differed significantly among the groups (P < 0.01; one-way ANOVA). Tukey's post-hoc tests revealed that the fracture resistance was similar in the control and SAF groups (P > 0.05) and was significantly higher than that of the 2 rotary and reciprocating groups (P < 0.01).


CONCLUSIONS
The samples instrumented by the SAF exhibited a better fracture resistance.
Department of Conservative Dentistry and Endodontics, D. Y. Patil Dental School and Hospital, Pune, Maharashtra, India.
Ajinkya M
AM
Pawar
Department of Conservative Dentistry and Endodontics, D. Y. Patil Dental School and Hospital, Pune, Maharashtra, India.
Digesh
D
Barfiwala
Department of Conservative Dentistry and Endodontics, Government Dental College and Hospital, Mumbai, Maharashtra, India.
Mansing
M
Pawar
Department of Endodontology, Tel Aviv University, Tel Aviv, Israel.
Zvi
Z
Metzger
Department of Endodontology, Tel Aviv University, Tel Aviv, Israel.
Anda
A
Kfir
Department of Conservative Dentistry and Endodontics, Hitkarini Dental College and Hospital, Jabalpur, Madhya Pradesh, India.
Niharika
N
Jain
Fracture strength; ProTaper; RECIPROC; Revo-S; WaveOne; instrumentation; self-adjusting file