初学者应用两种镍钛机动器械预备树脂弯曲根管的效果比较

目的 比较初学者应用两种机用镍钛器械Protaper和Her0642预备树脂弯曲根管的效果.方法 选取仿制单弯树脂根管32个,15名初学者分别用两种机用镍钛系统Protaper和Her0642进行根管预备,2个仿制单弯树脂根管为阴性对照.分别从推出根尖碎屑量、根尖偏移量及根管弯曲度变化等方面评价两种器械系统的根管预备效果.所有数据均采用SPSS 13.0软件包进行统计学分析.结果 Protaper组预备前后根管弯曲度平均减小6.77°,Hero642组减小5.480°,Protaper组减小根管弯曲度较Hero642组明显.Protaper组成形后的根管宽度均值均大于Hero642组,且根管口、根中1/3成形后的根管宽度差异有统计学意义(P<0.05).此外,根管预备过程中Protaper器械折断3支,Hero642器械折断1支.结论 对于初次使用机用镍钛器械的操作者,尽管Protaper具有良好根管成形的优点,但Hero642系统操作技术简单容易掌握、高效、安全,更适合初学者在临床上使用.     

弯曲根管用镍钛器械预备后根管偏移的研究

目的:研究3种镍钛根管预备器械预备后牙弯曲根管产生根管偏移的情况。方法:选择48个弯曲度>25°的下颌第一、二磨牙近中根包埋于Branmante模型中,分别用机动Hero642、Profile和手用ProTaper、不锈钢K锉进行根管预备。拍摄根管预备前后根尖、根中段横截面的影像,测定根管偏移的量、方向和轴中心率。结果:Hero642和Profile在根尖段和根中段根管的偏移显著小于不锈钢K锉,手用ProTaper仅在根尖段小于不锈钢K锉; 3种镍钛器械的轴中心率均低于不锈钢K锉,而镍钛器械组间无显著性差异;镍钛器械和不锈钢器械在根尖段根管中心偏向近中侧,而在根中段不锈钢K锉和手用ProTaper根管中心多数偏向远中侧,与Hero642和Profile有显著性差异。结论:Hero642、Profile和ProTaper在预备弯曲根管时有较小的偏移及良好的中心定位作用,尤其是Hero642和Profile对根尖和根中段成形能力较佳。     

两种镍钛机动器械预备根管的疗效评价

目的探讨机动镍钛器械Hero 642和ProTaper对根管的成形能力及其临床应用方法。方法60例60颗患牙分为2组,每组患牙30颗,分别采用机动镍钛器械Hero 642和ProTaper预备根管,侧向加压充填技术充填根管,根据治疗前后的X线片评价根管预备和充填效果,记录根管预备后器械折断、变形情况,1周后复诊,评价患牙的疼痛发生率。结果两组患牙根管预备后的根管不良形态率、根充适充率、术后疼痛率均无显著性差异。Hero 642操作简单,在根管预备过程中体现出较低的器械折断率。结论Hero 642和Protaper镍钛机动系统具有良好的根管成形作用,临床上可根据其各自的特点选用。     

不同根管预备器械对根管充填后冠方微渗漏影响的实验研究

目的:比较不同根管预备器械对根管充填后冠方微渗漏的影响。方法:选择60个单根管前磨牙(弯曲度为10～20°)随机分为6组,分别以不锈钢K锉、VDW K锉、手动Protaper、机用Protaper、Hero642、Mtwo预备根管。采用冷侧压法进行根管充填,染色法比较不同根管预备器械对根管冠方封闭性能的影响。结果:不同根管预备器械对充填后根管冠方微渗漏影响不同,其中Hero 642预备组、Protaper预备组、VDWK锉组冠渗漏长度少于不锈钢K锉组,且差异有统计学意义(P<0.05),Hero 642预备组产生的冠方微渗漏最小。结论:不同根管预备器械预备根管后对冠渗漏影响不同,镍钛旋转器械预备根管后产生的冠方微渗漏较小,不锈钢K锉根管预备后产生的冠方微渗漏较大。     

两种机用镍钛根管预备器械预备"S"形树脂根管的效果观察

目的探讨两种镍钛根管预备器械（ProTaper与Hero642）预备“S”形树脂根管的成形效果。方法将30个“S”形树脂根管模型分为3组，分别使用机用ProTaper（A组）、Hero642（B组）及ProTaper联合Hero642（C组）预备根管。使用扫描仪扫描获取根管图像，使用计算机软件测量预备后根管内、外侧树脂去除量和根管宽度。结果对比相同型号的器械对根尖部弯曲内侧、根尖孔外侧壁树脂去除量，C组与A组差异有统计学意义（P〈0．05），C组对根管内外侧壁的预备较均匀，预备后的根管宽度从根管口到根尖逐渐减小，优于B组预备的根管锥度。结论ProTaper联合Hero642预备“S”形树脂根管时能在维持根管原形的基础上形成锥度良好的管形。     

机用镍钛Hero642与不锈钢K锉预备弯曲根管的比较研究

目的比较机用镍钛器械Hero 642和手用不锈钢K锉对弯曲根管的预备效果.方法随机选择有弯曲根管的患牙髓炎和尖周炎的前磨牙和磨牙80个,分别采用机用镍钛器械Hero 642和手用不锈钢K锉进行根管预备,采用侧方加压充填,比较根管弯曲度的变化.结果Hero 642组平均减小1.85°,K锉组平均减小9.26°,二者之间有显著性差异(P＜0.01).结论Hero642能够更好地保持根管的原始走向,并且并发症少.     

机用镍钛Hero642与不锈钢K锉预备弯曲根管的比较研究

目的:比较机用镍钛器械Hero642和手用不锈钢K锉对弯曲根管的预备效果。方法:随机选择有弯曲根管的患牙髓炎和尖周炎的前磨牙和磨牙80个,分别采用机用镍钛器械Hero642和手用不锈钢K锉进行根管预备,采用侧方加压充填,比较根管弯曲度的变化。结果:Hero642组平均减小1.85°,K锉组平均减小9.26°,二者之间有显著性差异(P<0.01)。结论:Hero642能够更好地保持根管的原始走向,并且并发症少。     

两种镍钛机动器械预备根管的效果分析

目的　评价使用两种镍钛机动器械预备磨牙根管的临床疗效。方法　选取需行根管治疗的 10 0颗患有牙髓炎及根尖周炎的磨牙 ,分别使用机用镍钛器械Protaper、Hero6 4 2冠向下预备根管 ,两组均使用侧压充填法充填根管。记录根管预备时间及器械折断数量。根据治疗前、中、后的X线片计算弯曲根管的弯曲度变化 ,评价根管预备和充填的效果。结果　Protaper和Hero6 4 2预备根管时间短 ,根管锥度、流畅度好 ,术后疼痛发生少且程度轻。Protaper预备后根管弯曲度平均减小 4 0 2°,Hero6 4 2平均减小 1 72°,二者差异有统计学意义 (P <0 0 0 1)。Protaper器械折断 5支、Hero6 4 2未发生器械折断 (P <0 0 5 )。结论　镍钛机动器械Protaper、Hero6 4 2预备磨牙根管成形、根充效果好。Protaper减小根管弯曲度较Hero6 4 2明显 ,但易折断。Hero6 4 2操作简单 ,不易折断目的　评价使用两种镍钛机动器械预备磨牙根管的临床疗效。方法　选取需行根管治疗的 10 0颗患有牙髓炎及根尖周炎的磨牙 ,分别使用机用镍钛器械Protaper、Hero6 4 2冠向下预备根管 ,两组均使用侧压充填法充填根管。记录根管预备时间及器械折断数量。根据治疗前、中、后的X线片计算弯曲根管的弯曲度变化 ,评价根管预备和充填的效果。结果　Protaper和He     

4种机用镍钛器械预备模拟弯曲根管的效果评价

目的:比较4种机用镍钛器械预备模拟弯曲根管的成形效果。方法:40个单弯(弯曲度38.5°)树脂根管,随机编号分4组(Hero642、Protaper、K3及Mtwo)。按厂家推荐方法预备,记录预备时间,扫描仪获取图像,使用图像分析、测量软件将预备前、后的图像重叠,测量根管内、外侧壁树脂去除量、弯曲度及弯曲半径等的变化。采用SPSS13.0软件包对数据进行单因素方差分析。结果:K3预备速度最慢,Mtwo最快(P<0.05)。在根管弯曲起始点(BC)、根管口(O)和两者中点(HO)处内侧壁以及弯曲最凸点(AC)、HO和O处外侧壁的预备量4组间差异显著,Protaper预备后根管锥度变化最大,Hero642最小(P<0.05)。Protaper在根管弯曲段的中心定位能力最差;越接近根管下份偏移增大。K3与Protaper各1例断针,K3有2例台阶,安全性能、不良形态、根管弯曲角度及半径的改变方面,4种器械无显著差异,但预备后根管工作长度缩短,略有被拉直趋势。结论:Mtwo能快速预备根管;Protaper预备后根管锥度最明显;4种机用镍钛器械均具备良好的切屑力且维持原始根管走向。     

两种镍钛机动器械根管预备的比较研究

目的:评价两种镍钛机动器械预备后牙弯曲根管的效果。方法:选择根管弯曲度10°~20°之间,及>25°的单根管前磨牙各24个,包埋于Branmante模型中。采用Hero642和Profile镍钛机动系统进行根管预备。测定根管预备前后根尖、根中、根冠段的牙本质切削面积、形态因子,并记录操作时间和器械折断情况。结果:Hero642对根尖段及重度弯曲根管根中段的牙本质切削大于Profile,在根管预备过程中体现出较短的操作时间和器械折断率;根管预备后的截面形态在两者间无显著差异。结论:Hero642和Profile镍钛机动系统具有良好的根管成形作用,较高的工作效率,可作为临床上弯曲根管的预备器械。     

三种器械用于磨牙弯曲根管预备的临床评价

目的：评价不锈钢K锉、机用ProTaper和机用Safe Sider预备磨牙弯曲根管的临床疗效。方法：选取因牙髓炎或根尖周炎需要进行根管治疗的磨牙180颗（413个根管）,随机分为K-file组、ProTaper组和Safe Sider组,每组60颗牙。分别用不锈钢K锉、机用ProTaper和机用Safe Sider进行根管预备。三组均采用冷牙胶侧方加压技术充填根管。记录三组病例根管预备时间和术后并发症发生情况,根据治疗前、中、后的X线片评价根管预备和充填效果。结果：机用ProTaper、机用Safe Sider分别与不锈钢K锉在根管预备时间、根管成形以及充填效果方面在统计学上有显著性差异（P﹤0.05）,机用ProTaper与机用Safe Sider在上述方面无显著性差异（P﹥0.05）。结论：机用ProTaper和机用Safe Sider预备磨牙弯曲根管时能较好地保持原有根管形态,省时省力,术后反应少。     

Shaping ability of different NiTi rotary systems during the preparation of printed mandibular molars

This study aimed to evaluate the shaping ability of XP-endo Shaper, TruNatomy and EdgeFile X3 during the preparation of resin-printed mandibular molar mesial root canals. Thirty-three resin-based mandibular mesial roots with two canals, obtained from extracted tooth cone-beam computed tomography (CBCT) image and printed on a three-dimensional (3D) printer, were divided into three experimental groups according to the different nickel–titanium (NiTi) systems used for root canal preparation. The specimens were scanned using CBCT imaging before and after root canal preparation. Then images were registered using a dedicated software and changes in the canal area, volume, untouched canal surface and the maximum and minimum dentine wall wear were calculated. The XP-endo Shaper instruments showed improved shaping ability with lower untouched root canal surface and better preservation of root canal anatomy during the preparation of resin-printed mandibular mesial root canals compared with TruNatomy and EdgeFile X3 systems.     

两种机用镍钛根管预备器械在树脂模拟弯曲根管内的成形能力

目的 利用树脂模拟弯曲根管,研究K3和Hero642两种机用镍钛根管预备器械的成形能力.方法 使用K3和hero642分别预备两组树脂模拟弯曲根管至06锥度25#,运用扫描仪采集根管预备前后图像,Image ProPlus软件测量根管预备后的根管宽度和预备前后的弯曲度,使用SPSS13.0统计软件对预备前后树脂模拟弯曲根管宽度和弯曲度变化进行统计学分析.结果 K3组和Hero642组根管预备前后角度的变化分别为（4.11±0.18）°和（4.05±0.23）°,两者差异无统计学意义（P＞0.05）;两组器械预备后根管宽度的比较在根尖1/3、根中1/3和根管口处都无显著性差异（P＞0.05）.结论 两种机用镍钛根管预备器械均能较好地完成根管预备.     

两种机用镍钛器械根管预备的临床应用研究

目的评价两种设计特点不同的机用镍钛器械Hero642和Mtwo预备磨牙根管的临床效果。方法选取需行根管治疗的60颗患有牙髓炎或根尖周炎的恒磨牙,随机分为两组,分别使用机用镍钛器械Hero642冠向下法预备根管和Mtwo改良逐步后退法预备根管,两组均使用冷侧压法充填根管。根据治疗前后的X线片评价根管预备效果,比较器械损耗、预备时间及术中、术后并发症的发生率。结果两组均能形成较好的根管流畅度,但Mtwo组预备后根管锥度优于Hero642组（P〈0.05）。Hero642组预备时间短于Mtwo组（P〈0.05）。Mtwo组有两例发生器械分离、Hero642组未发生器械分离。结论Mtwo用于磨牙根管预备的成形效果优于Hero642,但Hero642具有省时、成本低且安全性好的优点。     

A comparative study of root canal preparation with HERO 642 and Quantec SC rotary Ni-Ti instruments

AIM: The purpose of this study was to compare several parameters of root canal preparation using two different rotary nickel-titanium instruments: HERO 642 (Micro-Mega, Besancon, France) and Quantec SC (Tycom, Irvine, CA, USA). METHODOLOGY: Fifty extracted mandibular molars with root canal curvatures between 20 micro and 40 micro were imbedded into a muffle system. All root canals were prepared to size 45 (Quantec SC), or 40 (HERO 642), respectively. The following parameters were evaluated: straightening of curved root canals, postoperative root canal diameter, safety issues (file fractures, perforations, apical blockages, loss of working length), cleaning ability, and working time. RESULTS: Both Ni-Ti-systems maintained curvature well; the mean degree of straightening was 2.3 degrees for Quantec SC and 1.6 degrees for HERO 642. Most procedural incidents occurred with Quantec SC instruments (five fractures, three apical blockages, eight cases of loss of working length), HERO 642 preparation resulted in three blockages and one perforation. Following preparation with HERO 642, 63% of the root canals showed a round, 24% an oval, and 17% an irregular diameter; Quantec SC preparations resulted in a round diameter in 24% of the cases, oval shape in 29%, and irregular cross-section in 47% of the cases. Mean working time was shorter for HERO 642 (52 s) than for Quantec (117 s). Cleanliness of the root canal walls was investigated under the SEM using a five-score system for debris and smear layer. For debris HERO 642 achieved better results (80% scores 1 and 2) than Quantec SC (76%). The results for smear layer were similar: cleaner root canal walls were found after preparation with HERO 642 (53% scores 1 and 2), followed by Quantec SC (41%). CONCLUSIONS: Both systems respected original root canal curvature well and showed good cleaning ability; Quantec SC showed deficiencies in terms of safety.     

Comparative study of torsional and bending properties for six models of nickel-titanium root canal instruments with different cross-sections

This study investigated the influence of cross-section profile on the mechanical behaviors of six commercial nickel-titanium (NiTi) root canal instruments using the finite element method. The nonlinear mechanical characteristics of the NiTi alloy were taken into account. The six root canal instruments studied were ProTaper, Hero642, Mtwo, ProFile, Quantec, and NiTiflex. Mathematical models for these instruments were constructed and their performances were analyzed under equal torque conditions. The ProTaper and Hero642 models achieved the lowest stress levels that made them the most torque-resistant while the NiTiflex model was the poorest. The maximum stress value and the stress distribution in a model were found strongly influenced by the cross-section profile. Factors affecting the stress distribution include the cross-sectional inertia, depth of the flute, area of the inner core, radial land, and peripheral surface ground. As the area of the inner core of the cross-section increased, the model was more torque-resistant.     

A comparative SEM investigation of the smear layer following preparation of root canals using nickel titanium rotary and hand instruments

The aim of this study was to compare the efficacy of NiTi flex K-file instruments and rotary FlexMaster and Race instruments (short for reamers with Alternating Cutting Edges) in root canal preparation. A total of 75 single rooted teeth with minimum curvature (< 5 degrees ) were selected and divided into three groups, each containing 25 teeth. Canals were prepared with NiTi flex K-file, FlexMaster and Race instruments using crown down preparation technique, up to size #40. After each instrument, the root canals were flushed with 5 ml of 0.5% NaOCl solution. The amount of debris and smear layer was quantified on the basis of Hulsmann method using a scanning electron microscope. Completely cleaned root canals were not found after instrumentation with any of the three instruments. In general, FlexMaster instruments left significantly less debris and smear layer than Race and NiTi flex K-file instruments (P < 0.05). NiTi flex K-files resulted in significantly more smear layer (P < 0.05) compared to Race and FlexMaster instruments only in the apical third of the canal.     

倒敞法结合2 种机用镍钛锉预备重度弯曲后牙根管的应用研究

目的:评价倒敞法结合Hero 642和ProTaper机用镍钛锉预备重度弯曲后牙根管的疗效.方法: 随机将100 颗患牙髓炎或根尖周炎、最大根管弯曲度≥25°的后牙分为2 组,各50 例.实验组(A组)采用倒敞法,而对照组(B组)不采用倒敞法机械预备.A组以机用开口锉根管中上端敞开后,手用K锉预备根尖,再先用镍钛器械Hero 642,后用ProTaper预备根管;B组则直接应用Hero 642和ProTaper冠向下法预备根管. 2 组均用侧压法充填根管.根据X线片情况,预备时间,器械折断、疼痛等并发症,评价根管预备和充填的疗效,1 年随访率95%.结果:A组倒敞法结合Hero 642和ProTaper机用镍钛锉预备重度弯曲后牙根管,锥度、流畅度好,术后疼痛少且程度轻,无器械折断;而B组发生器械折断3 支(P>0.05);充填恰充率、欠充率、流畅度、术后疼痛两者有显著性差异(P<0.05).结论: 倒敞法结合Hero 642和ProTaper机用镍钛锉预备重度弯曲后牙根管,成形、根充效果好,并发症少,最大限度发挥了各自优点,是预备重度弯曲后牙根管值得推广应用的有效方法.     

新型机动镍钛器械预备根管的疗效评价

目的:探讨新型机动镍钛器械Hero642预备根管的临床疗效。方法:选取患牙髓炎或根尖周炎的恒磨牙60例(60颗患牙),试验组用机动镍钛器械Hero642及根向预备技术预备根管,对照组用K锉及逐步后退技术预备根管,两组均采用侧向加压充填技术充填根管。根据治疗前后的X线片评价根管预备和充填效果,t检验比较两组根管弯曲度和操作时间,χ2检验比较根管内并发症和术后疼痛的发生率。结果:试验组能维持根管的原走向,无根尖阻塞、台阶、根管偏移及侧壁穿孔等并发症发生,对照组并发症的发生显著多于试验组(P<0.005);试验组操作时间短,术后疼痛发生少。结论:机动镍钛器械Hero642预备根管快速、有效,成形效果好,值得临床推广应用。