R-相热处理镍钛锉预备S形树脂根管成形能力的体外研究

Shaping ability of R-phase nickel-titanium rotary instruments in simulated S-shaped canals

目的 比较TF、K3和EndoWave 3种机用镍钛锉预备S形树脂模拟根管的成形能力。方法 120个S形树脂模拟根管,随机分为3组,每组40例,使用TF、K3和Endo Wave 3种器械分别进行根管预备,记录预备时间;数码显微镜获取预备前、后根管图像,使用Photoshop和Image J软件进行图像重叠,测量预备后根管冠方弯曲角度和根方弯曲角度的变化值;从根尖止点开始,每隔1mm测量根管内、外侧壁树脂去除量,共10个测量点。以外弯量减去内弯量,表示中心定位能力。单因素方差分析进行统计学检验,显著性水平0.05。结果 TF预备时间为（14.00±4.56）s,显著短于K3和Endo Wave[（59.53±35.92）s和（44.00±14.38）s]（P〈0.05）。3种器械预备后根管冠方和根方弯曲角度变化差异无统计学意义（P〉0.05）。3种器械预备后,根尖弯曲处,TF在内侧壁树脂去除量显著小于Endo Wave和K3（P〈0.05）;冠部弯曲处,TF在外侧壁去除量显著小于K3（P〈0.05）;根管直线段,TF在内侧壁的去除量显著小于Endo Wave和K3（P〈0.05）。中心定位能力方面,TF在距根尖孔5~9mm位点均显著优于Endo Wave（P〈0.05）;除距根尖止点6mm位点以外,其他位点TF均与K3差异无统计学意义。结论 TF预备S形树脂模拟根管效率高,不良预备形较少且根管偏移较小。

Objective To evaluate the shaping ability of TF, EndoWave and K3 instruments in simulated S- shaped root canals. Methods A total of 120 simulated S-shaped resin blocks were divided randomly into three groups （n = 40）, each group was prepared with each instrument, respectively. Preparation time was recorded. Pre- and postoperative images were obtained by a digital microscope and superimposed using Photoshop. The change of curvatures, and material removal from the inner and outer canal walls at 10 points beginning from 0 mm at the end point of the canal were measured using ImageJ. Centering ability was determined, accordingly. The data were analyzed using the One-Way ANOVA at a significance level of P 〈 0. 05. Results Preparation time for TF was 14.00 ± 4.56 s, significantly faster than that for K3 and EndoWave, while the changes of curvatures were not significantly different among the three instruments. At the apical curve, the removal of resin from the inner wall by TF was significantly less than EndoWave and K3 （ P 〈 0.05 ）. At the coronal curve, the material removal from the outer wall of TF were significantly less than K3 （ P 〈 0. 05 ）. At the straight part, TF removed significantly less material from the inner wall than EndoWave and K3 （P 〈 0. 05 ）. At points from 5 mm to 9 mm, the transportation of TF were significantly less than EndoWave （ P 〈 0. 05 ）, while that of TF was not significantly different with that of K3 （ P 〉 0. 05 ） , except for the 6 mm point （ P 〈 0. 05 ）. Conclusion TF prepares S-shaped resin canals efficiently, with less aberrations and transportations than EndoWave and K3.