Faculdade de Medicina Dentária, Universidade de Lisboa, Lisboa, Portugal.
Grupo de Investigação em Bioquimica e Biologia Oral, Unidade de Investigação em Ciências Orais e Biomédicas (UICOB), Faculdade de Medicina Dentária, Universidade de Lisboa, Lisboa, Portugal.
Int Endod J. 2023 Nov;56(11):1412-1428. doi: 10.1111/iej.13971. Epub 2023 Sep 12.
To compare the design, metallurgy, and mechanical properties of four heat-treated reciprocating instruments coupled with the evaluation of the irrigation flow using an in silico model.
New EdgeOne Fire Primary, Easy-File Flex Regular 25, WaveOne Gold Primary and Reciproc Blue R25 instruments (n = 124) were initially evaluated regarding their design through stereomicroscopy, scanning electron microscopy and 3D surface scanning. In addition, energy-dispersive X-ray spectroscopy was utilized to determine their elemental composition, and differential scanning calorimetry tests to evaluate their phase transformation temperatures. Their mechanical performance was further assessed through torsional and bending tests. Using scans obtained from a real tooth and the instruments, a computational fluid dynamics assessment was conducted to determine the irrigation flow pattern, apical pressure, and wall shear stress in simulated canal preparation. Mood's median and One-way anova post hoc Tukey tests were used for statistical comparisons (α = 5%).
Reciproc Blue exhibited a superior number of blades (n = 8), whereas EdgeOne Fire had the highest overall volume (4.38 mm ) and surface area (32.32 mm ). At the 3-mm axial level, EdgeOne Fire displayed the lowest core diameter (0.13 mm), while Reciproc Blue had the highest (0.16 mm). All blades were symmetrical, and the tips of the instruments were non-active but differed from each other. The most irregular surfaces were observed in EdgeOne Fire and Easy-File Flex. All instruments were manufactured from nickel-titanium alloys and exhibited distinct phase transformation temperatures. WaveOne Gold and Reciproc Blue demonstrated the highest maximum torque values (1.87 and 1.62 N cm, respectively), while the lowest was observed on EdgeOne Fire (1.21 N cm) (p < .05). The most flexible (p < .05) were EdgeOne Fire (angle of rotation: 602.6°; maximum bending load: 251.4 g.f) and Reciproc Blue (533.2° and 235.6 g.f). There were no significant differences observed in the irrigation flow among the four domains generated by the tested instruments.
Despite observing variations in the design, phase transformation temperatures, and in the torsional and bending test outcomes among the four heat-treated reciprocating instruments, no significant differences were found in the irrigation flow pattern among the different groups in the simulated root canal preparations.
通过计算机模拟模型，比较四种经热处理的往复器械的设计、冶金和机械性能，并评估其冲洗流量。
对 New EdgeOne Fire Primary、Easy-File Flex Regular 25、WaveOne Gold Primary 和 Reciproc Blue R25 器械（n=124）进行初始评估，通过立体显微镜、扫描电子显微镜和 3D 表面扫描观察其设计，此外，还利用能量色散 X 射线光谱法测定其元素组成，利用差示扫描量热法评估其相变温度。通过扭转和弯曲试验进一步评估它们的机械性能。利用从真实牙齿和器械获得的扫描结果，进行计算流体动力学评估，以确定模拟根管预备中冲洗流量模式、根尖压力和管壁剪切应力。采用中位数 M oods 和单向方差分析事后 Tukey 检验进行统计比较（α=5%）。
Reciproc Blue 具有更多的刀片（n=8），而 EdgeOne Fire 具有最大的总体体积（4.38mm ）和表面积（32.32mm ）。在 3mm 轴向水平上，EdgeOne Fire 的芯部直径最低（0.13mm），而 Reciproc Blue 的芯部直径最高（0.16mm）。所有刀片均为对称刀片，器械尖端非活性，但彼此不同。最不规则的表面出现在 EdgeOne Fire 和 Easy-File Flex 中。所有器械均由镍钛合金制成，并表现出明显的相变温度。WaveOne Gold 和 Reciproc Blue 显示出最高的最大扭矩值（分别为 1.87 和 1.62N·cm），而 EdgeOne Fire 的扭矩值最低（1.21N·cm）（p<.05）。最灵活的（p<.05）是 EdgeOne Fire（旋转角度：602.6°；最大弯曲载荷：251.4g·f）和 Reciproc Blue（533.2°和 235.6g·f）。在模拟根管预备中，四种经热处理的往复器械产生的四个区域之间的冲洗流量没有显著差异。
尽管观察到四种经热处理的往复器械在设计、相变温度以及扭转和弯曲试验结果方面存在差异，但在模拟根管预备中，不同组之间的冲洗流量模式没有发现显著差异。
