Gambarini G, Miccoli G, Seracchiani M, Morese A, Piasecki L, Gaimari G, Di Nardo D, Testarelli L
Department of Oral and Maxillo Facial Sciences, Sapienza University of Rome, Rome, Italy.
Department of Periodontics and Endo- dontics, University at Buffalo, New York, USA.
Clin Ter. 2018 May-Jun;169(3):e96-e101. doi: 10.7417/T.2018.2061.
Aim of the present study was twofold. First, to evaluate in vitro, the performance of two different NiTi rotary instruments in one molar case; then, to evaluate their resistance to cyclic fatigue, compared to new ones.
25 ProTaper Next (PTN) nickel-titanium (NiTi) instruments (Maillefer-Dentsply, Baillagues, CH) for each of the following two sizes: X1 (17.04 ) and X2 (25.06) were randomly divided into two groups. The first group (n = 10) immediately under- went to a cyclic fatigue test. The second group (n = 15) was initially used to prepare 15 extracted molar teeth and then subjected to a cyclic fatigue test. Same was done for 25 Horizen (HZ) instruments (Kerr Endodontics, Orange, Ca) for each of the following two sizes: 20.04 and 25.06. Instruments were rotated in curved artificial canal until fracture occurred and times to fracture were recorded. All data were collected and statistically analyzed using a variance test (confidence interval CI = 95%).
HZ reached working length more rapidly than PTN, and with less deformations. For the fatigue tests, all the new instruments were significantly more resistant than the used ones. The HZ instru- ments were significantly more resistant in all sizes than PTN, both when new and used instruments were tested.
Since in previous studies ProTaper Next demonstra- ted a better resistance to cyclic fatigue than most of nickel-titanium instruments, Horizen's performance put them in a high rank amongst the most resistant nickel-titanium rotary instruments.
本研究有两个目的。其一，在体外评估两种不同镍钛旋转器械在一个磨牙病例中的性能；其二，与新器械相比，评估它们的抗循环疲劳性能。
25支ProTaper Next（PTN）镍钛（NiTi）器械（Maillefer-Dentsply，Baillagues，瑞士），每种以下两种尺寸：X1（17.04）和X2（25.06），随机分为两组。第一组（n = 10）立即进行循环疲劳测试。第二组（n = 15）最初用于预备15颗拔除的磨牙，然后进行循环疲劳测试。对25支Horizen（HZ）器械（Kerr Endodontics，Orange，加利福尼亚州），每种以下两种尺寸：20.04和25.06，进行同样操作。器械在弯曲的人工根管中旋转直至折断，记录折断时间。收集所有数据并使用方差检验（置信区间CI = 95%）进行统计学分析。
HZ比PTN更快达到工作长度，且变形更小。对于疲劳测试，所有新器械比使用过的器械显著更抗疲劳。无论是新器械还是使用过的器械进行测试，HZ器械在所有尺寸上都比PTN显著更抗疲劳。
由于在先前研究中ProTaper Next比大多数镍钛器械表现出更好的抗循环疲劳性能，Horizen的性能使其在最抗疲劳的镍钛旋转器械中名列前茅。
