三种不同器械预备弯曲根管时根管偏移的实验研究

目的 :研究镍钛合金 (Nickel-titanium ,NiTi)根管预备器械与不锈钢 (stainlesssteel,SS)器械预备弯曲根管时保持原根管解剖走向的能力。方法 :选择离体的人下颌单根管前磨牙 45个 ,弯曲度为 2 0°～40°。随机分为 3组 ,分别用SS -K锉、手用NiTi器械NiTiflex、机用NiTi器械ProFile .0 4进行根管预备 ,对根管偏移结果进行对比分析。结果 :NiTi器械无 1例出现根管偏移 ,而SS器械自 # 2 5开始均可发生根管偏移 ,且随器械号的增大而增加。结论 :NiTi器械保持原根管解剖走向的能力优于SS器械 ,SS器械使偏移根管的数目随号数的增大而增加     

弯曲根管的临床预备要点

弯曲根管的根管预备是根管治疗的难点，直接决定根管治疗的成功率。本文简述了近年来出现的新根管锉系统，保持弯曲根管预备后原有形状的技巧，以及改良的根管预备方法，对弯曲根管的临床预备作一较全面综述。     

预备弯曲根管时根管偏移的实验研究

目的：定量研究弯曲根管预备过程中根管的偏移。方法：使用不锈钢K锉按常规法预备8个弯曲人工根管，根管预备过程中对根管、根尖孔进行微距摄影，用图像分析软件Image—Pro Plus对根管的形态和位置变化进行测量、分析。结果：根管预备时随着锉号的递增，弯曲根管逐渐被拉直，表现为根管弯曲角度逐渐减小，弯曲半径、根管轮廓面积逐渐增大，根管口、根尖孔被拉开，根管壁出现3个过度切削区。结论：预备弯曲根管时，根管不同部位的偏移方向、偏移距离并不相同，掌握弯曲根管的解剖形态以及根管器械的力学性能，有助于准确估计根管偏移的大小和方向。     

弯曲根管的临床预备要点

弯曲根管的根管预备是根管治疗的难点,直接决定根管治疗的成功率。本文简述了近年来出现的新根管锉系统,保持弯曲根管预备后原有形状的技巧,以及改良的根管预备方法,对弯曲根管的临床预备作一较全面综述。     

三种根管器械预备弯曲根管的效果比较

目的:比较不锈钢K型锉(K-file)、手动镍钛合金锉(N i-Ti flex)和机动镍钛锉Profile(PF)预备弯曲根管时,保持原根管解剖走向的能力。方法:选择45个离体下颌单根管前磨牙,弯曲度为20°~45°,随机分为3组,分别用不锈钢K锉(SS-K锉)、手动镍钛器械(N i-Ti flex)、机动镍钛器械Profile进行根管预备。治疗前后分别拍摄可高度重叠的X线片,通过计算机扫描和放大,分析比较各组之间维持原根管形态的差异,并记录各组的操作时间和器械分离的发生率。结果:镍钛手动器械和机动器械都能较好地保持原根管解剖走向,SS器械所致的根管偏移的数目随器械号数的增大而增加,#30以上的器械,镍钛组(包括手动和机动)保持根管解剖走向能力与SS组相比有显著差异性(P<0.05),两镍钛锉之间无显著性差异。机动镍钛组有一器械分离,操作时间机动组比手动组快(P<0.01)。结论:对于弯曲根管,当根尖部预备大于#30时,镍钛锉保持根管原解剖走向的能力优于不锈钢锉,机动器械比手动器械操作时间短。     

3种方法预备磨牙弯曲根管的临床研究

目的比较双敞法、逐步后退法、逐步深入法用于弯曲根管预备的临床疗效。方法选择中、重度弯曲根管磨牙120颗,按就诊顺序随机分为3组,试验组40颗牙用双敞法、对照1组40颗牙用逐步后退法、对照2组40颗牙用逐步深入法预备根管后充填根管。根管充填完成后拍根尖片观察充填情况,记录根管预备后的并发症发生率。1周后完成冠部修复并随访2年,评价治疗效果。结果试验组根管预备并发症发生率为5.0%,对照1组并发症发生率为25.0%,对照2组并发症发生率为22.5%,试验组与对照1组的差异有统计学意义(χ2=6.26,P<0.05),试验组与对照2组的差异也有统计学意义(χ2=5.17,P<0.05)。术后2年随访观察,试验组成功率为92.5%,对照1组和对照2组成功率分别为70.5%和72.5%,试验组和对照1组的差异有统计学意义(χ2=6.65,P<0.05),试验组和对照2组的差异也有统计学意义(χ2=5.54,P<0.05)。结论双敞法预备弯曲根管,能有效减少根管预备并发症,提高根管治疗的成功率。     

三种根管预备器械预备弯曲根管的临床研究

目的　比较三种根管预备器械预备后牙弯曲根管的临床情况 ,从而评价镍钛机动根管预备器械的临床应用前景。方法　研究对象为年轻下颌第一恒磨牙 30例 ,分别采用手动不锈钢器械、手动镍钛器械和机动镍钛器械进行根管预备 ,治疗前后分别拍摄可高度重叠的X线片 ,通过计算机扫描和放大比较根管拉直情况以及根尖孔敞开、台阶和侧穿的发生率。并记录各组的操作时间和器械折断发生率。结果　对于低度弯曲的根管 ,不锈钢组比镍钛组更易造成根管拉直 (P <0 .0 1)。对于高度弯曲的根管来说 ,不锈钢组与镍钛组 ,相差更为明显 (P <0 .0 1)。治疗失败在各组均有发生 ,操作时间机动组比手动组要快 (P <0 .0 1)。结论　机动镍钛根管预备器械具有良好的临床应用前景     

3种器械预备弯曲根管的比较研究

目的 :比较不锈钢K型锉、镍钛合金K型锉以及镍钛合金X型锉预备弯曲根管的根尖偏移。方法 :将 4 5个 15°～ 35°的弯曲前磨牙根管按弯曲度排序后均匀分成 15个区组 ,每区组 3个根管 ,再随机分配至3个不同器械处理组。根管冠部用GG钻预处理后 ,行常规法预备根管 ,拍摄数字化X线片记录预备至不同锉号时根管器械尖端所在位置。最后 ,将根管预备前后器械尖端相应位置描记后 ,在立体显微镜下测量不同锉号根管预备后的根尖偏移。结果 :3组标本的根尖偏移均随锉号的增大而增大 ,# 35和 # 4 0不锈钢K型锉根管预备所致的根尖偏移与另外两组标本相比有显著性差异 (P <0 .0 5 ) ,另有两个标本根管侧穿 ;两组镍钛合金锉之间的根尖偏移无显著性差异 (P >0 .0 5 )。结论 :对于弯曲根管 ,用镍钛合金锉预备 ,其效果优于不锈钢锉。     

3种根管扩大器械预备弯曲根管的体外实验

目的：运用手持根管扩大器械预备弯曲根管，观察根尖偏移发生率，方法：选取57颗弯曲单根管离体前磨牙作为研究对象，随机分成三组，A组19颗用Lightspeed镍钛合金器械预备根管，B组运用K锉，C组运用H锉，C组运用H锉，预备方法均为逐步后退技术，使用双曝光技术判断根尖偏移情况，结论：A组中有19％的根管发生了根尖偏移，B组中有82％发生了根尖偏,C且中有88％发生了根尖偏移，结论：运用Lightspeed镍钛器械预备弯根管可以减少根尖偏移的发生。     

弯曲根管预备器械和方法的研究进展

弯曲根管的预备历来是根管预备中的难点,由于其特殊的形态很容易出现各种并发症,难以达到根管预备的要求。本文就近年来弯曲根管预备器械和方法的研究进展作一综述。     

Comparison of three instruments in the preparation of curved root canals

Abstract The transportation produced in the apical and middle areas of 30 mesiobuccal root canals of human mandibular molars was evaluated after circumferential instrumentation using stainless steel K-files (group A), nickel-titanium K-files (group B), and clockwise/counterclockwise file rotation using Flexogates (group C). The canals were instrumented with files #15 to #35 in size. Apical transportation was assessed radiographically while that occurring in the middle area was studied microscopically in cross-sections. Although apical transportation was greatest in the canals of group A, this difference was not statistically significant (P>0.05). With respect to the middle area of the root canal, considerable transportation was observed in 7 of the 30 instrumented roots. Of these, live belonged to group A and two to group B, a difference which was not statistically significant (P>0.05). The best results for transportation in the middle area of the canal were obtained in group C, in which no transportation occurred. This difference was significant when compared with the transportation observed in group A (P=0.02) but not with that in group B (P>0.05).     

Effectiveness of two different methods for preparing curved root canals

Abstract In this study, the effect of using two different methods for preparing curved root canals of extracted, single-rooted teeth were analyzed with the scanning electron microscope. The instrumentation systems tested were the Canal Master and a standard circumferential filing technique in which conventional K-files were used. Shaping effectiveness was qualitatively evaluated in terms of respect for conservation of the apical constriction and the presence or absence of ledging, specially in the apical third of the root canals. As a result of our observations, it appeared that the Canal Master instrumentation technique provided well-centered and tapered preparations. Conversely, the use of conventional K-files with a standard circumferential filing technique resulted in frequent alterations of the initial pattern of the root canals, showing transportation of the apical foramen and ledge formation.     

Comparison of three instrumentation techniques in the preparation of simulated curved root canals

Forty-five acrylic blocks with simulated curved canals were divided into three groups of 15 blocks each. In group 1 the canals were instrumented with ultrasoni-cally energized K-files (UEF) using a piezoelectric ultrasonic device. In group 2 the canals were prepared with ProFile 0.04 Taper Series 29 Rotary Instruments (PRI) in conjunction with a low-speed high torque handpiece. In group 3 (control) the canals were hand instrumented (HI) with conventional K-type files using a standard push-pull circumferential technique. The efficiency of these techniques for preparing the simulated canals were compared by measuring the amount of transportation of the prepared canals at different levels from the working length using a double exposure photographic technique. A statistical analysis was used to indicate any significant difference among groups. The results showed that the use of PRI provided well-centred and more tapered preparations. Conversely, the use of UEF and HI resulted in frequent alteration of the original curvature, showing transportation at different levels from the working length.     

4种镍钛器械预备弯曲根管后成形能力比较

目的:比较4种镍钛器械预备弯曲根管后的成形能力.方法:收集临床上拔除的近颊根牙根弯曲度在20°～40°的上颌第一或第二恒磨牙40颗,随机分为4组,每组10颗,分别采用Protaper Universal、Protaper Next、TF、S3对近颊根进行根管预备.预备前、后采用Micro-CT扫描,使用Mimics17...     

声波、超声波、手用根管器械预备弯曲根管的效果比较

目的：比较声波、超声波和手用根管器械预备弯曲根管的效果。方法：采用3种根管器械预备树脂块模拟根管并进行比较。结果：30个树脂块模拟根管预备效果显示：声波、超声波和手用器械根管预备效果无显著性差异。结论：声波根管器械具有临床应用价值。     

Effectiveness of nickel-titanium files for preparing curved root canals

Abstract In this study, the effect of 2 different endodontic files on the final shape of curved root canals of extracted single rooted teeth were examined in the scanning electron microscope. The instruments tested were a newly designed nickel-titanium endodontic file and a conventional K-type file. The files were used with in and out linear movements with a circumferential motion starting with a size 15 file. Final preparation of the apical thirds of the canals was performed with a size 35 file. Shaping effectiveness of the tested instruments was evaluated in terms of respect for conservation of the apical constriction and the presence or absence of ledging. Our observations revealed that more centered and tapered preparations were obtained with the use of the nickel-titanium files than with the conventional K-type files.     

三种器械预备弯曲根管成形效果的比较

目的：评价K锉、Safesiders锉和HERO Shaper锉预备离体牙弯曲根管的成形效果。方法60颗根管弯曲的离体下颌前磨牙随机分为3组,分别用K锉、Safesiders锉和HERO Shaper锉进行根管预备,根管预备前后分别往根管内注入复方泛影葡胺并拍摄X线片,分析根管预备后根管弯曲内外侧壁牙本质去除量、中心定位能力及根管直化角度。结果在根管弯曲内外侧壁所有观测点,Safesiders锉组和HERO Shaper锉组牙本质去除量均少于K锉组（P均＞0.05）。 Safesiders锉组牙本质去除量多于HERO Shaper锉组,但仅在根管弯曲内侧壁3和4 mm观测点处差异有统计学意义（3 mm：t＝3.72,P＜0.05;4 mm：t＝7.62,P＜0.05）。在距根尖孔5 mm以下观测点,Safesiders锉组和HERO Shaper锉组中心定位能力优于K锉组（1 mm：F＝7.45,P＜0.05;2 mm：F＝10.20,P＜0.05;3 mm：F＝7.75,P＜0.05;4 mm：F＝23.45,P＜0.05;5 mm：F＝10.91,P＜0.05）;而在所有观测点上,Safesiders锉组与HERO Shaper锉组差异均无统计学意义（P均＞0.05）。 Safesiders锉组和HERO Shaper锉组根管直化角度均小于K锉组（F＝58.95,P＜0.05）,但Safesiders锉组与HERO Shaper锉组间差异无统计学意义（P＞0.05）。结论 K锉、Safesiders锉和HERO Shaper锉预备离体牙弯曲根管均有不同程度的根管偏移,其中Safesiders锉和HERO Shaper锉根管偏移较少,具有较好的根管成形效果。     

两种镍钛器械联合预备弯曲根管的效果评价

目的：评价联合使用K3和TF两种不同镍钛器械预备弯曲根管的效果。方法：选择离体下颌前磨牙及磨牙各40颗,依根管弯曲度分为轻度及中重度弯曲组,每组再随机分为两组,分别采用K3联合TF、单独K3进行根管预备。记录并分析各组单根管预备时间、并发症、根管直化角度、器械中心定位能力。结果：轻度弯曲组采用K3联合TF进行根管预备仅预备时间明显短于K3组（P<0．05）;中重度弯曲组采用K3联合TF进行根管预备,预备时间、术中并发症、根管直化角度、自根尖孔1～4 mm观测点的器械中心定位能力与K3组相比均有统计学差异（ P<0．05）。结论：K3联合TF预备弯曲根管,可节省操作时间,减少并发症,更好地维持根管原有形态,尤其适用于中重度弯曲根管的预备。     

两种根管再治疗镍钛器械去除椭圆形弯曲根管内充填物的效果评价

目的:评价2种根管再治疗镍钛器械去除椭圆形弯曲根管内充填物的效果。方法:离体的80颗根管呈椭圆形且弯曲的下颌前磨牙经Hero642预备、热牙胶垂直加压充填后随机分为4组,分别用ProTaper Universal、R-Endo、Hero642和手用H锉去除根充物,测量各组根充物的残留量百分比和操作时间。结果:4组样本均有根充物残留,ProTaper Universal、R-Endo和Hero642组根充物残留量百分比、操作时间均少于手用H锉组(P<0.01),前3组间的差异无统计学意义(P>0.05)。结论:ProTaper Universal、R-Endo机动镍钛器械对椭圆形弯曲根管内充填物的清除效果优于手用器械,且可减少操作时间,但仍不能彻底清除根充物。