ABSTRACT
Objectives:
The study’s objective was to contrast the two distinct rotary file techniques used to shape mandibular first molars.
Materials and Methods:
The investigation involved twenty recently removed mandibular molars. A digital single-lens reflex (DSLR) camera was placed in a fixed position, a muffle block was built, and images of each tooth’s three cross sections were obtained. The specimens were split into the following two groups at random: Rotary files from WaveOne were used to prepare group A and Mtwo rotary files were used to prepare group B.
Results:
At the coronal, middle, and apical thirds of the root canals, WaveOne file system demonstrated improved centering ability compared with the Mtwo file system (P 0.05).
Conclusion:
When compared to the Mtwo file system, WaveOne file system demonstrated improved centering capabilities and needed significantly less time to build the curved canals.
KEYWORDS: Centering ability, Mtwo file, WaveOne
INTRODUCTION
An effective endodontic instrumentation strategy should uniformly prepare all of the canal surfaces while preserving the sound peripheral dentin. Because of their greater flexibility compared with their SS counterparts, the development of instruments made from nickel–titanium (NiTi) alloys has dramatically improved root canal shaping in terms of quality and time.[1]
Iatrogenic mistakes, such as ledges, zips, perforations, and apical conveyance, frequently occur while sculpting extremely curved canals. Numerous preparatory approaches and instrument systems have been developed to reduce these iatrogenic mistakes.[2]
To improve the dependability and effectiveness of rotary instruments in managing the preparation of curved canals, significant adjustments have recently been proposed. Numerous NiTi instruments have been introduced as a result of this trend.[1] A recent WaveOne reciprocating single-file system has been created. There are three single-use files in the WO system. A multiple-file system utilized for root canal shaping is the Mtwo file system.[2] It has a non-cutting tip and an S-shaped cross-sectional design.[3]
The purpose of this study was to assess the centering abilities of the WaveOne and M2 file systems in the mandibular molars’ curved mesial canals.
MATERIALS AND METHODS
Twenty freshly extracted mandibular molars, for periodontal reasons were divided evenly into two groups; group A-WAVE ONE rotary files (Dentsply, Maillefer, Ballaigues, Switzerland) with size 25, taper 8% and Group B-. Mtwo file system with size 25, taper 8% across the first three mm from the apical tip (Mtwo,VDW, Munich, Germany). Before use, teeth were chosen based on the inclusion criteria and cleaned.
By removing the crown with diamond disks from each tooth specimen, any one canal of the mesial root was standardized to a length of 9 mm (Dentsply Maillefer, Ballaigues, Switzerland), which used International Organization for Standardization (ISO) No. #10 K files to check the canals for apical patency. Using the Schneider technique, the degree and radius of canal curvature were identified from preoperative radiographs using CorelDRAW X6 software tools.[4]
The canals were positioned in the muffle block using self-curing acrylic resin after the apices were wax-sealed. A narrow cutting disk was used to cut the blocks into three horizontal sections at the coronal, middle, and apical locations. Three cross sections of every tooth were photographed using a DSLR camera (Nikon Digital, Tokyo, Japan) in a fixed posture. One skilled operator prepared all of the canals. Thorough irrigation with side-vented, close-ended needles and 5.0 ml of 5% Sodium hypochlorite (NaOCl) solution. All sectioned canals were divided after instrumentation, and pictures taken after instrumentation were taken in the same way as those taken before instrumentation. The computer program CorelDRAW X6 software was used to assess the rotary instruments’ shaping capabilities. To assess the canal centering ratio, transportation, and pre and post-instrumentation, measurements were obtained.
Using statistical software SPSS version 20.0, the obtained data were assessed using the normality tests of Kolmogorov–Smirnov (K-S) and Levene’s variance homogeneity analysis of variance (ANOVA), as well as the post hoc Tukey’s HSD (honestly significant difference) test at P 0.05.
RESULT
In the present research, the WaveOne (WO) file system showed superior centering ability compared with the Mtwo file system (P < 0.05) at all three diverse positions: coronal, middle, and apical thirds of the root canals [Table 1]. The absence of instrument fracture or deformation was found.
Table 1.
Intergroup comparison of centering ability at coronal, middle and apical thirds of the root canals
| Location | Group | Mean | P |
|---|---|---|---|
| Coronal | Group A | 1.038 | <0.001* |
| Group B | 1.538 | ||
| Middle | Group A | 1.375 | <0.001* |
| Group B | 1.578 | ||
| Apical | Group A | 1.354 | <0.001* |
| Group B | 1.497 |
DISCUSSION
In the coronal, middle, and apical thirds of the root canals, the WaveOne file system demonstrated superior centering capability compared with the M2 file system, according to the study’s findings.
WaveOne is composed of M-wire alloy, whereas ProTaper is constructed of traditional martensitic NiTi, and WaveOne promotes centered instrumentation more than a continuous rotating motion does.[5]
Bürklein et al.[6] discovered no discernible difference between the single-file technique and a full NiTi file sequence technique. Yuan and Yang claimed that both of the two instrument sets successfully preserved the canals’ original outlines. Less transportation was required for the canals made with ProTaper Next (PTN), and the apical region was better served.[2]
Through the use of many factors, including canal surface, volume, uninstrumented canal surface area, and structure model index (SMI), the impacts of canal instrumentation were quantitatively examined.[2] According to Kuzekanani et al.,[3] Mtwo tools are preferred in cases where canals are curved, especially for maxillary molars.
CONCLUSION
When compared to the Mtwo file system, the WaveOne file system demonstrated superior centering capabilities and needed significantly less time to build the curved canals.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
REFERENCES
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