Comparative evaluation of canal cleaning ability of various rotary endodontic filesin apical third: A scanning electron microscopic study

Abstract

Background:The purpose of this study was to evaluate the canal cleaning ability of three novel endodontic rotary instruments and compare with ProTaper files as a control in apical third of root canals under scanning electron microscopy (SEM).Materials and Methods:Eighty freshly extracted mandibular premolars were selected according to inclusion criteria. Buccal cusp tips were ground to ensure having a flat coronal reference point with a total tooth length of 16 mm for all samples. Teeth were divided equally into four groups: Group I (ProTaper group), Group II (ProTaper next group), Group III (variable taper group), and Group IV (self-adjusting file [SAF] group). Using SEM, the dentinal surfaces were observed and rated at apical thirds with a magnification of ×1000 for the presence/absence of smear layer and debris. Descriptive analysis was performed, and analysis of variance with Bonferroni post hoc test was carried out for comparison between the groups, at a significance level of 0.05.Results:There was statistically significant difference between Group II and Group IV for debris (P = 0.047) and smear layer (P = 0.037).Conclusion:In apical third of root canal, SAF showed statistically significant canal cleaning ability due to combined effect of continuous streaming irrigation with effectively replacing the irrigant from the apical portion of the root canal, irrigants activation through the creation of turbulence, and its self-adapting design to root canal anatomy with a scrubbing motion on the canal walls.

Root canal cleaning with different reciprocating and rotary instrumentation systems

“…With all four file systems, partially uninstrumented areas with remaining debris were found in all canal sections. This finding has also been described by others (5,19,22,23). In the present study, completely cleaned root canals were not found in any group.…”

“…Here, two reciprocal files were compared with traditionally used rotary systems (that is ProTaper file) for their canal cleaning ability and reciprocal instruments better than rotational systems for debris and smear removal. In the present study our ProTaper universal and Protaper next results similar the Jadhav's research (23).…”

“…However, difference between Protaper and Protaper next was not statistically significant. Jadhav et al showed the same result in their study (23). In the present study, WaveOne and Reciproc groups showed better result than ProTaper groups.…”

“…SEM is a valuable method to assess the cleaning effects because of allowing evaluations of the entire section of both halves of the canal on the basis of a separate numeric evaluation scheme for debris and smear layer (23). In the present study, the cleaning efficiency was analyzed by means of an SEM-evaluation of the coronal, the middle and the apical parts of the canals (22).…”

“…Debris and smear layer have been used as criteria in this study to evaluate the cleaning ability of the different instruments because debris includes dentine chips, residual vital or necrotic pulp tissue attached to the root canal wall that is thought to be infected in many cases (22). Debris and smear layer lead to following difficulties during endodontic treatment an unpredictable thickness and volume due to greater water portion limits its removal and optimum penetration of disinfectant and obturated material its loosely adherent nature is a potential avenue for leakage (23). Debris and smear layer removal depends not only the irrigation method but also on the design of endodontic instrument (size, taper, cross-section, etc), the way instrument is used (rotational or reciprocal) and the method of preparation (step back or crowndown) (10,24).…”