Performance of Three Single Instrument Systems in the Preparation of Long Oval Canals

Abstract

This study aimed to evaluate the performance of the Wave One, Easy ProDesign Logic and One Shape systems in the preparation of long oval root canals. Forty-two mandibular incisors were randomized into three groups: Group I, Wave One Primary (WO) (#25.08); Group II, Easy ProDesign Logic (EPL) (#25.06) and Group III, One Shape (OS) (#25.06). Micro-computed tomography scans were obtained pre- and post-preparation of the samples. Instrument fractures or loss of working length did not occur in any of the groups. There was a statistically significant difference in total root canal volume between the WO and EPL (p<0.05) and OS systems (p<0.05) The mean percentages of instrumented canal area in the middle thirds were 76.9% in the WO, 62.3% in the EPL and 71.8% in the OS (p>0.05). The OS system had the strongest correlation between volume increase and instrumented area (R=0.63). The WO, EPL and OS systems presented mean preparation times of 2.13 min, 0.54 min, and 2.21 min (p<0.05), respectively. All three systems enabled the safe preparation of long oval root canals. The WO system most effectively increased root canal volume, but it did not affect the instrumented areas. The OS system had the strongest correlation between volume increase and instrumented area, while the EPL system was the fastest.

Shaping ability of rotary or reciprocating systems for oval root canal preparation: a micro-computed tomography study

“…However, in spite of the increase in volumetric values, a higher percentage of untouched areas were also observed for this system. In previous studies, WaveOne, for example, promoted a higher increase in the volume value of the canal, with a similar percentage of uninstrumented surfaces of oval canals to Easy ProDesign Logic and OneShape systems [27]. It was also observed that although the SAF system touched the canal walls to a larger extent, it removed less dentin in the preparation of oval root canals [18].…”

Root canal preparation using micro-computed tomography analysis: a literature review

“…1,2,3,4,5 Since 2012, new protocols for biomechanical root canal preparation have been developed using nickeltitanium (NiTi) instruments, whose flexibility and resistance to torsion allow their use in a continuous rotating movement; these in turn reduce the working time, operator fatigue, and the risk of operative accidents. 6,7,8,9,10,11,12,13,14,15 NiTi instruments have been developed with various geometric conformations, 8 with the most significant design difference being the taper with conicity ranging from 2% to 12%, compared to the standard 2% taper of stainless steel instruments established by ANSI/ADA in 1976 and updated in 1982. 8 NiTi rotary instruments were first commercialized in the 1990s, and since then about 700 studies have been published in journals indexed in PubMed before June 2010.…”

“…These instruments are manufactured with a M-Wire alloy from a thermal treating process of the NiTi alloy, which provides greater flexibility and resistance to cyclic fatigue than the conventional NiTi alloy. 4,9,11,13,15,33,34,35,36,37,38,39,40,41,42,43,44,45 The movement dynamics of these instruments, known as reciprocating, is the rotation in the counterclockwise direction (cutting direction) followed by a less extensive clockwise rotation (instrument releasing direction), facilitating continuous and progressive movement toward apical. 15,26 According to some authors, the reciprocating movement reduces the risk of torsion fracture because the instrument is not subjected to the stress levels caused by a continuous rotary motion.…”

“…15,26,46,47,48 Another system for the preparation of the root canal based on the concept of a single instrument, but with continuous rotation, is the OneShape system (MicroMega, Besançon, France). 11,49,50 This system is produced from conventional NiTi alloy using a tip diameter of #25 and continuous 0.06 taper, with three different cross-sections along the active part, variable pitch, and idle spirals, with the goal of reducing the tapping effect. 11,50,51,52 This was also a goal for several other systems, including Race (FKG Dentaire S.A., La Chaux-de-Fonds, Switzerland), Rondo (FKG Dentaire S.A., La Chaux-de-Fonds, Switzerland), EndoSequence (Brasseler USA Dental, Savannah, USA), and EndoWave (J. Morita Corporation, Osaka, Japan), which presented a design of helical angles and alternating areas and, more recently, systems including BioRace (FKG Dentaire S.A., La Chaux-de-Fonds, Switzerland), Revo-S (Micro-Mega, Besançon, France) and ProTaper Next (Dentsply Maillefer, Ballaigues, Switzerland).…”

“…27,76,77,78 The development of micro-CT allows a more precise RCS evaluation than a conventional CT scanner, and more recent use of specific software has made it possible to accurately assess the biomechanical preparation as well as the anatomy, root canal filling, and retreatment. 2,3,4,5,7,9,11,12,13,14,15,25,27,28,29,30,31,34,35,37,38,39,40,41,42,43,44,45,47,56,57,58,59,61,62,63,68,79,80,81,82,83,84,85,86,87,88,…”