# Comparison of Hand Files, Mtwo, Reciproc, and Gentlefile Rotary Systems Regarding Canal Transportation, Centering Ability, and Obturation Quality of Primary Molars

## TL;DR

This study compares different dental instruments for root canal treatments in primary molars, focusing on how well they follow the canal path and fill the canals.

## Contribution

The study introduces a comparative analysis of canal transportation, centering ability, and obturation quality using four different root canal instrumentation systems in primary molars.

## Key findings

- Mtwo showed better centering ability than Gentlefile at 2mm from the apex in the mesiodistal direction.
- Reciproc had the highest obturation density, followed by Mtwo, Gentlefile, and hand files.
- Gentlefile exhibited higher canal transportation compared to other systems.

## Abstract

Employing different instruments may have different impact on the outcome of root canal treatments. Deviation from the original canal path and defective root canal obturation may lead to pulpectomy treatment failure.

This study compared the primary molar canal transportation, centering ability, and obturation quality of hand files, Mtwo, Reciproc, and Gentlefile rotating machines in root canal treatments.

In this in vitro experimental study, eighty primary molar roots were randomly assigned to four groups. Cone-beam computed tomography (CBCT) scans were provided for the samples, and hand files (group 1), Mtwo (group 2), Reciproc (group 3), and Gentlefile (group 4) were used to instrument the root canals. Once more, CBCT scans were acquired, and at 1, 2, and 3mm from the apex as well as 1 mm from the orifice, the canal transportation and centering ability were evaluated in buccolingual and mesiodistal directions. Zeolite (ZOE) cement was used to obturate every root canal. To evaluate the obturation density, number of voids, and underfilling in each group, new CBCT scans were obtained. For every tooth, the maximum, minimum, and average Hounsfield units (HU) were noted. One-way ANOVA, the Kruskal-Wallis test, and Tukey's HSD test were used to analyze the data.

Mtwo exhibited considerably superior centering ability than Gentlefile at 2mm from the apex in the mesiodistal direction (p Value< 0.05).
Gentlefile had significantly higher buccolingual canal transportation than Reciproc at 3 mm from the apex (P0.05). Minimum HU, underfilling, and void numbers did
not differ amongst the four groups (p= 0.791, p= 0.1, and p= 0.548). Reciproc had substantially higher maximum and average HU, followed by Mtwo, Gentlefile,
and hand files (p< 0.05).

When compared to other systems, Gentlefile showed higher transportation and less centering ability. Reciproc had the highest obturation density, followed by Mtwo, Gentlefile, and hand files.