2种机用镍钛器械根管成形效果的对比研究

目的:比较2种不同类型机用镍钛根管预备器械Mtwo、K3的根管成形效果.方法:选择36个离体上颌第一磨牙的近中颊侧根管.根据其弯曲度分成A(弯曲度≥20°)、B(弯曲度＜20°)2组,每组再随机分成2个亚组,分别采用镍钛锉Mtwo和K3进行根管预备.预备前后,分别向根管内注入造影剂并拍摄数字X线片,利用合作研制的计算机图像分析软件生成预备前根管几何中心线并投影至预备后根管,测定根管偏移量(几何中心线偏移量)及根管弯曲度的变化.所有数据用SPSS11.0软件包进行统计学分析.结果:各组样本经t检验分析,根管弯曲度≥20°时,根管弯曲起始处的根管偏移量Mtwo组显著小于K3组(P＜0.05);根管弯曲度减小量Mtwo组显著小于K3组(P＜0.05).根管弯曲度＜20°时,Mtwo、K3组间根管偏移量及根管弯曲度减小量均无显著性差异(P＞0.05).结论:Mtwo、K3根管预备时均能良好维持原始根管的中心位置;预备弯曲度大于20°根管时,Mtwo可更好维持原始根管弯曲度及走向.     

3种机用镍钛器械在重度弯曲根管预备中根管成形能力的研究

目的：比较机用镍钛Protaper、K3、iRaCe在重度弯曲根管预备中的根管成形能力。方法：收集新鲜拔除的人恒磨牙60颗,要求其中一个根管的弯曲角度为25°～45°,分为Protaper组、K3组和iRaCe组,每组20颗。每颗牙分别在根管预备前后拍摄标准化的平行投照片,通过影像分析来记录根管弯曲度的变化值和根尖偏移量,同时记录折断的器械和根管预备的时间。结果：实验过程中3个组均无器械折断。K3组、iRaCe组在根管预备后根管弯曲角度的变化小于Protaper组,差异有统计学意义（P〈0．05）,K3组和iRaCe组之间差异也具有统计学意义（P〈0．05）。Protaper组、K3组的根尖偏移量大于iRaCe组,差异有统计学意义（P〈0．05）,Protaper组和K3组之间差异无统计学意义（P〉0．05）。三组在操作时间上的差异无统计学意义（P〉0．05）。结论：iRaCe和K3在重度弯曲根管预备中的根管成形能力较Protaper要好,更适合用于重度弯曲根管预备。     

A comparison of the shaping characteristics of two nickel-titanium endodontic hand instruments

AIM: The purpose of this study was to compare the shaping characteristics of Ni-Ti K-files and Ni-Ti S-files manipulated by hand. METHODOLOGY: A total of 60 extracted human roots were embedded in resin blocks. The embedded roots were divided into three groups: (i) roots with straight; (ii) apically curved; and (iii) continuously curved canals. Each of the three groups was randomly divided into two subgroups; one subgroup in each group was prepared with Ni-Ti K-files and the other with Ni-Ti S-files. The files were used with a step-back technique and enlarged so that the master apical file was size 30, and the canals were stepped back to size 40. The performance of the files was assessed by the superimposition of projected radiographs taken in bucco-lingual and mesio-distal directions before and after the preparation. The results were analysed statistically using analysis of covariance and Duncan's multiple range test. RESULTS: Although canal preparation using Ni-Ti K-files was quicker, there were no statistically significant differences between file types. The Ni-Ti S-file removed significantly more material at the most coronal level (P < 0.05). There were minor differences between instruments at the apical level. Only in the proximal view of apically curved canals prepared with Ni-Ti S-files was significantly more dentine removed from the outer aspect of the curvature (P < 0.05). At the middle level (wide danger zone) the Ni-Ti S-files removed more dentine from the inner aspect of the curvature in those roots with apically curved canals. CONCLUSIONS: Under the conditions of this study, preparation with Ni-Ti K-files produced more appropriate shapes in roots with apically curved canals than Ni-Ti S-files.     

两种根管镍钛锉对L形和S形根管成形能力的研究

目的 评价两种机用镍钛锉对弯曲根管的预备成形能力.方法 20个L形树脂根管,随机分为2组,每组10个,分别使用#25,0.04锥度的M3铂金版、S3预备根管,术前术后拍摄数码照片,绘制根管外形线及中心线,分析根管预备前、后工作长度和弯曲角度变化值及根管中心线偏移量.另20个S形树脂根管,分组方法 和实验方法 同L形根管...     

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...     

手用镍钛锉对弯曲根管根管成形能力的评价

目的：评价手用镍钛锉（ISO）预备弯曲根管时的根管成形能力。方法：利用自主研制的《牙齿模拟根管辅助分析测量系统》软件，定量检测8个模拟根管在用手用镍钛锉（ISO）以提拉方式预备前后的形态变化，并进行统计学分析。结果：手用镍钛锉（ISO）虽有良好的弹性，但以四壁提拉方式预备根管时仍有明显拉直根管的趋势。手用镍钛锉对弯曲根管的各部位切割很不均衡。结论：结果提示仅有弹性好的手用镍钛锉并不能保证获得弯曲根管预备的良好效果，预备方式和手法的改进是弯曲根管预备所必须的。     

Dentine chips produced by nickel-titanium rotary instruments

Abstract – This study aimed to compare the cross-sectional shape of two nickel-titanium rotary instruments, namely ProFile and Quantec files, both ISO 25, 0.06 taper, and sought to relate this to the chips produced by cutting dentine. A limited comparison was made with stainless steel engine reamers. First, five files of each type were sectioned transversely at 12 mm, 8 mm and 4 mm from the tip and examined by scanning electron microscopy. The cutting angles were assessed by a direct measurement technique which allowed for the inclination of a cutting edge to the root canal. Second, eight samples of cutting debris were collected from instrumentation by each type of nickel-titanium file and four samples from the engine reamers. The major and minor axis, area and roundness of the dentine chips in each sample were measured using computerized particle analysis. The results demonstrated that all files had a negative cutting angle which varied at the different levels (ProFiles range 69.4° to 58.4° and Quantec range 74.8° to 56.8°). The consistency within files of the same type was good as demonstrated by low standard deviations, except for Quantec files at the 4 mm level where higher standard deviations of 4.1° and 5.5° for the two blades were found. The chip analysis showed significant differences between chips produced by ProFile and Quantec files ( P <0.05). The latter were larger and rounder. The chips from the ProFile and the engine reamer chips were similar in dimension ( P >0.05). No simple relationship existed between file geometry and the dentine chips produced during instrumentation.     

Influence of different types of automated devices on the shaping ability of rotary nickel-titanium FlexMaster instruments

AIM: To compare the shaping ability of rotary FlexMaster nickel-titanium instruments in simulated curved canals and in curved canals of extracted teeth when set into permanent rotation with three different torque-limited automated devices. METHODOLOGY: Root canal instrumentation was performed with three different torque-limited automated devices (ENDOadvance, SIRONiTi and Endo IT motor) by FlexMaster nickel-titanium instruments up to size 35. Simulated canals: 28 degree and 35 degree curved canals in resin blocks (n = 20 canals in each group) were prepared. Pre- and post-instrumentation images were recorded and assessment of canal shape was completed with a computer image analysis program. Extracted teeth: A total of 60 curved root canals were divided into three groups, which were balanced with respect to the angle and the radius of canal curvature. Straightening of the canal curvatures was determined with a computer image analysis program. Incidence of canal aberrations, preparation time, changes of working length and instrument failures were recorded both in simulated and real canals. RESULTS: In simulated and real canals, instrumentation with Endo IT was significantly faster than with SIRONiTi (P < 0.05). With respect to canal aberrations in simulated canals, there were no significant differences between the devices (P > 0.05), even though more aberrations were created with ENDOadvance and SIRONiTi. In real canals, the Endo IT motor resulted in significantly less straightening during instrumentation (P < 0.05) than SIRONiTi. A total of three instruments separated (one file in each group) during the enlargement of 35 degree curved simulated canals. All systems maintained working distance well. CONCLUSIONS: All systems respected original root canal curvature well and were safe, indicating that torque-limited rotation handpieces are suitable for preparing curved root canals.     

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。     

三种镍钛器械对弯曲根管成形能力的实验研究

目的 比较Reciproc、Reciproc Blue和Protaper 3种机用镍钛器械在弯曲根管中成形能力的差异,为临床器械选择提供实验依据.方法 选择透明树脂弯曲根管30个,随机分成3组.分别用Reciproc(R组)、Reciproc Blue(RB组)和Protaper(P组)机用镍钛锉进行根管预备,记录预备...     

Mtwo机用镍钛器械预备感染根管的临床对照研究

目的研究Mtwo机用镍钛器械预备感染根管的临床效果。方法选择56例患者共68个感染根管,随机分为Mtwo组（35个）与ProTaper组（33个）,Mtwo组采用单一长度技术预备根管,ProTaper组采用冠根向深入法预备根管。分别于预备前后根管内取样,接种,培养,然后检测厌氧菌量的变化;记录两组根管预备所需时间;患牙术后疼痛情况;摄片比较两组根管预备和充填质量。结果两组根管预备后厌氧菌量均明显减少,Mtwo组厌氧菌减少量大于ProTaper组;Mtwo组术后疼痛发生率较高;两组都能在较短时间内完成根管预备,都有较好的根管适充率。结论 Mtwo可以高效的清除根管内感染,有良好的根管成形能力,值得在临床推广应用。     

机用镍钛器械预备后牙狭窄弯曲根管的临床研究

目的临床评价使用4种机用镍钛器械预备后牙狭窄弯曲根管的治疗效果。方法需进行根管治疗的磨牙或前磨牙狭窄弯曲根管170个,按患者就诊顺序随机分成4组。TF组44个根管,采用TF机动预备;PathT组42个根管,采用PathFile联合TF机动预备;P组41个根管,采用ProTaper机动预备,PathP组43个根管,采用PathFile联合ProTaper机动预备。4组根管预备后均采用热牙胶连续波垂直加压充填。记录4组的根管预备时间、器械分离数量,根据x线片观察术前与术后根管弯曲度的变化量,评价根充效果。结果TF组、PathT组、P组、PathP组的根管预备时间分别为（3．50±0．13）rain、（2．80±0．09）min、（5．39±0．08）min、（4．66±0．12）min,4组根管预备时间差异具有统计学意义（F=374．081,P〈0．001）,PathT组根管预备时间最短（P〈0．05）,PathP组（t=28．65）、TF组（t=34．67）根管预备时间均短于P组（P〈0．001）。4组中PathT组根管弯曲度变化量最小（0．90°±0．69°）,与其余3组比较差异有统计学意义（P〈0．05）;4组根充效果理想。未发现欠充及牙胶尖超克,TF组与P组出现2例糊剂超充,PathT组与PathP组各出现1例糊剂超充。结论与ProTaper相比,Tr锉能缩短狭窄弯曲根管的预备时间,与PathFile联合使用,则能进一步提高根管预备效率,减少根管偏移。     

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机用镍钦器械的发展与应用,为临床医生创造了获得最佳根管预备效果的可能性,是根管预备技术的一场革命.机用镍钛器械从螺纹设计、几何外形到锥度,与传统标准器械存在很大差别.这些改变不仅提高了根管预备的效率,也最大限度减少了根管的移位和变形,但同时临床医生也面临着机用镍钛器械折断的风险.本文对根管镍钛器械的特点以及目前常用机用镶钦器械的操作方法、操作原则等方面加以阐述.     

Shaping ability of Quantec Series 2000 rotary nickel-titanium instruments in simulated root canals: Part 1

The aim of this study was to determine the shaping ability of Quantec Series 2000 nickel-titanium instruments in simulated canals. A total of 40 simulated root canals made up of four different shapes in terms of angle and position of curvature were prepared by Quantec instruments using the technique recommended by the manufacturer. Part 1 of this two-part report describes the efficacy of the instruments in terms of preparation time, instrument failure, canal blockages, change in canal length and three-dimensional canal form. The time necessary for canal preparation was on average 5.7 min and was significantly influenced ( P < 0.01) by canal shape. One instrument fractured and three size nine instruments deformed; however, canal shape did not influence significantly instrument failure. All of the canals remained patent, none became blocked with debris. The majority of the canals maintained working distance (26 out of 40), however the mean change in length differed significantly ( P < 0.05) between canal types. Overall, canals with 40° curves lost length whilst those with 20° curves gained in length. Examination of intracanal impressions revealed that preparation with Quantec Series 2000 instruments produced canals with definite apical stops, smooth canal walls and good flow and taper. However, the quality of apical smoothness and flow was influenced significantly ( P < 0.0001) by canal shape with specimens having 40° canals displaying less desirable qualities. Under the conditions of this study, Quantec Series 2000 rotary nickel-titanium instruments prepared simulated canals rapidly, safely and with good three-dimensional form.     

4种机用镍钛根管通畅锉通道制备能力的对比研究

目的对临床中使用的4种机用镍钛根管通畅锉根管制备后的形态进行分析,评价4种通畅锉的通道制备能力。方法32个树脂根管(弯曲角度28~30°)随机分为4组,每组8个,分别使用M3-path0.02(A组)、M3-path双通道版(B组)、Scout RaCe0.02(C组)、RaCe ISO10(D组)制备根管通道,采集术前、术后图像,使用Photoshop和Caxa软件处理图像,测量术前、术后根管直径、弯曲角度及中心线偏移量并进行分析。结果弯曲角度变化值:A、B、C组小于D组(P<0.05)。中心线偏移量:在根尖段,C组最小;在弯曲段,B组、D组大于A组、C组;在直线段,D组最大,B组次之,A、C组最小(P<0.05)。通道制备后根管直径:在根尖段,D组最小(P<0.05);在弯曲段3~5mm位点,D组最大(P<0.05),B组与A组、C组接近(P>0.05);弯曲段6~7mm位点及根管直段,D组最大,B组次之,A、C组较小(P<0.05)结论4种器械均有较好的中心定位能力,0.02锥度通畅锉在根管全长的中心定位能力更优,大锥度通畅锉在根管中上段的预敞效果更好。     

Shaping ability of NT Engine and McXim rotary nickel-titanium instruments in simulated root canals. Part 1

The aim of this study was to determine the shaping ability of NT Engine and McXim nickel-titanium rotary instruments in simulated root canals. In all, 40 canals consisting of four different shapes in terms of angle and position of curvature were prepared by a combination of NT Engine and McXim instruments using the technique recommended by the manufacturer. Part 1 of this two-part report describes the efficacy of the instruments in terms of preparation time, instrument failure, canal blockages, loss of canal length and three-dimensional canal form. Overall, the mean preparation time for all canals was 6.01 min, with canal shape having a significant effect ( P <0.01) on the speed of preparation. One instrument fractured and only four instruments deformed, with most of the failures occurring in canals with curves which began 12 mm from the orifice, that is, in short acute curves. None of the canals became blocked with debris. Following preparation, 20 canals retained their original working length but 19 lost length and one gained in length; there were significant differences ( P <0.05) between the canal shapes in terms of mean loss of distance and in the category of distance change. Apical stops as determined from intracanal impressions were present in 37 of the canals; 16 were judged to be of good quality and 21 of poor quality. The canals were found to be smooth in the apical half of the canal in 33 specimens and in the coronal half of 39 specimens. All canals had good taper characteristics and 35 had good flow characteristics. Under the conditions of this study, NT Engine and McXim instruments prepared canals rapidly, with few deformations, no canal blockages and with minimal change in working length. The three-dimensional form of the canals demonstrated good flow and taper characteristics.     

Shaping ability of Hero 642 rotary nickel-titanium instruments in simulated root canals: Part 1

AIM: To determine the general efficacy and shaping ability of Hero 642 nickel-titanium rotary instruments during the preparation of simulated canals. Part 1 of this two-part report describes the efficacy of the instruments in terms of three-dimensional canal form. METHODOLOGY: A total of 40 simulated root canals made up of four different shapes in terms of angle and position of curvature were prepared by Hero 642 instruments using a crown-down preparation sequence. The efficacy of the instruments was assessed in terms of preparation time, instrument failure, canal blockages and loss of canal length. Intra-canal impressions were taken of the prepared canals in order to assess three-dimensional canal form. RESULTS: The mean time for canal preparation was 8.6 min and was influenced significantly (P < 0.05) by canal shape. Two instruments fractured and eight instruments deformed; significant differences were observed between canal shapes (P < 0.05). All of the canals remained patent. Fifteen canals (39.5%) maintained the correct working distance, 15 lost distance and eight canals gained length. Examination of intracanal impressions demonstrated that the majority of canals (79%) had apical stops; canal shape had a significant influence (P < 0.001) on the quality of apical stops. With one exception all canals had smooth canal walls and all of the canals showed good flow characteristics. Taper was poor in 30 canals (79%) and good in eight canals (21%). CONCLUSIONS: Hero 642 rotary nickel-titanium instruments prepared simulated canals rapidly but with a three-dimensional form that lacked adequate taper.     

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

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EndoWave 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ImageJ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1 mm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EndoWave[(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EndoWave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EndoWave和K3(P＜0.05).中心定位能力方面,TF在距根尖孔L 5～ 9mm位点均显著优于EndoWave(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.     

往复运动镍钛锉根管预备成形能力的体外研究

目的 比较4种机用镍钛器械预备树脂模拟弯曲根管的成形能力,为临床应用提供实验依据。方法 40个单弯树脂模拟根管随机分为4组,每组10个,分别使用Reciproc（组1）、WaveOne（组2）、Mtwo（组3）和ProTaper（组4）进行根管预备,记录4组的预备时间,测量预备后根管的工作长度;使用扫描仪获取4组预备前后的根管图像,使用Photoshop和 Image J软件进行图像重叠并测量预备后根管弯曲角度的变化值,从距根尖孔1 mm开始,每隔1 mm测量根管内外侧壁树脂去除量,共10个测量点,计算中心定位能力。使用单因素方差分析、Kruskal-Wallis检验和SNK检验进行统计学分析,检验水准为双侧α=0.05。结果 组2预备时间最短,为（53.7±6.7）s,组1、组3和组4分别为（86.9±8.1）、（112.2±8.2）、（177.9±11.2）s,4组间差异有统计学意义（P<0.05）。4种器械预备前后根管工作长度变化的差异无统计学意义（P>0.05）。组1、组2、组3、组4根管弯曲角度变化值分别为（2.671±0.637）° 、（2.667±0.450）°、（3.664±0.870）°、（3.797±0.601）°,组1和组2的变化值显著小于组3和组4（P<0.05）。在距根尖孔3 mm位点,组1的偏移程度为（-0.016±0.094） mm,显著小于其余3组（P<0.05）;在距根尖孔4 mm和5 mm处,组2的偏移程度分别为（-0.080±0.104） mm和（-0.312±0.088） mm,显著小于组1 [（-0.243±0.099） mm和（-0.404±0.064） mm,P<0.05]。结论 Reciproc和WaveOne可快速有效地预备根管,且可较好地保持树脂弯曲根管的原始形态;Reciproc在根尖区具有较好的中心定位能力,WaveOne在根管弯曲中段部分具有较好的中心定位能力。     

Shaping ability of Quantec Series 2000 rotary nickel-titanium instruments in simulated root canals: Part 2

The aim of this laboratory based study was to determine the shaping ability of Quantec Series 2000 nickel-titanium rotary instruments in simulated root canals. A total of 40 canals with four different shapes in terms of angle and position of curve were prepared with Quantec Series 2000 instruments using the technique recommended by the manufacturer. Part 2 of this report describes the efficacy of the instruments in terms of prevalence of canal aberrations, the amount and direction of canal transportation and overall post-operative shape. Pre- and post-operative images of the canals were taken using a video camera attached to a computer with image analysis software. The pre- and post-operative views were superimposed to highlight the amount and position of material removed during preparation. Twenty-one zips and elbows were created during preparation with a significant difference (P < 0.005) between canal shapes in terms of the incidence of aberrations. Four perforations were created, with significant differences (P < 0.005) between the canal shapes; three ledges were also created but no danger zones. Highly significant differences (P < 0.001) were apparent between the canal shapes in total canal width at specific points along the canal length and in the amount of resin removed from the inner and outer aspects of the curve. Canal transportation at the end-point of preparation was most frequently directed towards the outer aspect of the curve, and without exception in canals with 40° curves. At the beginning of the curve, transportation became more evenly balanced between the inner and outer aspect of the curve, although predominated towards the outer. Transportation was generally directed towards the outer at the orifice, especially in canals with 40° curves. Mean absolute transportation at the various measurement points was less than 0.11 mm; significant differences occurred between canal shapes at the end-point of preparation (P < 0.0001), at the zips (P < 0.005), at the apex (P < 0.0001) and beginning of the curve (P < 0.05) and at the orifice (P < 0.0001). Under the conditions of this study, Quantec Series 2000 rotary nickel-titanium instruments created a relatively large number of aberrations including four perforations. The aberrations were created by the larger instruments implying that these should be used with caution at the full working distance. Scanning electron micrographs of these instruments revealed sharp instrument tips which appeared likely to predispose to transportation and the creation of defects along the outer aspect of severely curved canals.