微焦点计算机断层扫描术评价根管再治疗中不同器械根管清理效果的研究

目的基于微焦点计算机断层扫描术（Micro-CT）数据建立人前磨牙三维模型,定量评价根管再治疗过程中2种根管预备系统根管清理的效果。方法选择因正畸治疗拔除的前磨牙40颗,采用ProTaper机用镍钛锉进行根管预备,冷牙胶侧方加压法充填根管。随机分为2组,以弹性K锉和ProTaper Universal再治疗系统分别进行根管二次预备。分别于根管充填及二次预备后进行Micro-CT扫描,计算根管内剩余充填物比例,分别对根管冠1/3、中1/3和下1/3的根管内剩余物进行评分,评价2种器械对根管充填物的清理效果。结果使用弹性K锉进行根管二次预备的平均根管内剩余物比例低于ProTaper Universal再治疗系统（P=0.005）;弹性K锉组根尖1/3清理效果优 ProTaper Universal 再治疗系统组（P<0.05）。结论弹性K锉和ProTaper Universal再治疗系统均不能完全清除根管内充填物。     

两种镍钛锉清除椭圆形弯曲单根管内充填物的效果评价

目的：评价两种镍钛器械清除椭圆形弯曲单根管内充填物的效果。方法75颗椭圆形弯曲单根管下颌前磨牙经Hero642镍钛器械根管预备后用热牙胶垂直加压充填,随机分为3组,分别以机用ProTaper Universal Retreatment( ProTaper UR)镍钛锉、机用Mtwo镍钛锉和手用不锈钢H锉去除根管内充填物,X线片法测量各组根管内颊舌向和近远中向根管充填物的残留量百分比,并记录操作时间。结果3组根管内均有根管充填物残留。ProTaper UR组和Mtwo组颊舌向(F=7.94,P<0.01)和近远中向(F=26.93,P<0.01)根管充填物残留量百分比、操作时间(F=37.6,P<0.01)均少于H锉组,但ProTaper UR组和Mtwo组间颊舌向(t=0.23,P=0.81)和近远中向(t=0.36,P=0.76)根管充填物残留量百分比和操作时间(t=41.35,P=0.08)的差异均无统计学意义。结论 ProTaper UR镍钛锉和Mtwo镍钛锉对椭圆形弯曲单根管内充填物的清除效果优于不锈钢H锉,且可缩短操作时间,但仍不能完全去除根管充填物。     

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。     

ProTaper镍钛系统去除根管内充填物的效果评价

比较ProTaper镍钛系统去除不同充填方法的根管内充填物的效果。A组:侧方加压法充填;B组:热牙胶垂直加压法充填。2组均采用ProTaper Universal再治疗器械(D1,D2,D3)+ProTaper Universal(F2,F3,F4)去牙胶及根管再预备,测量镍钛器械操作时间及根管内充填物的残留量。B组根管壁充填物残留量低于A组,镍钛器械所需时间高于A组。2组中牙胶残留物均主要位于根尖三分之一区域。ProTaper镍钛系统去除垂直加压法充填的牙胶管壁清洁度较高。     

3种器械去除根管内牙胶充填物的效果评价

目的：比较H型锉和两种再治疗镍钛旋转器械去除根充物的效果。方法：45颗离体单根管下颌前磨牙,使用ProTaper镍钛器械根管预备,热牙胶垂直加压根管充填。标本随机分为3组（n=15）用不同方法去除根充物。A组H型锉、B组ProTaper Universal和C组Hero Shaper,分别记录再治疗所用时间。将标本沿牙体长轴纵劈,用立体显微镜观察根管壁残留的牙胶,t检验和单因素的方差分析one way ANOVA进行统计学分析。结果：B组根管内残留充填物的量较其他两组更少（P〈0.05）;B、C两组操作时间明显短于A组（P〈0.05）,而B、C两组间,C组用时较少,但没有显著性差异。结论：根管再治疗中,所有器械均会残留根充物,ProTaper Universal镍钛再治疗器械可以有效去除单根管下颌前磨牙根管内充填物。     

取断针失败后根管充填方法的选择和评价

目的探讨取断针失败后的根管的充填方法。方法制备80颗根尖含根管断针的离体牙模型,实验组对照组各半。实验组（预备组）预备根管,制备断针取出失败时的根管模型;对照组（非预备组）将断针模型不经预备直接进行根管充填,两组都用塑化液和牙胶根充糊剂进行根管充填,使用透明牙法观察对断针的封闭效果。结果①非预备组中塑化封闭根尖效果优于糊剂牙胶充填效果（P〈0.05）②预备组塑化治疗与糊剂牙胶根尖封闭效果无明显差异（P〉0.05）。结论临床上断针且取出失败时,宜选择牙胶和根充糊剂充填根管。     

不同根管预备方法对老年人根管再治疗术后疼痛的影响

目的：对比ProTaper镍钛系统冠向下预备法和采用不锈钢手用锉逐步后退技术两种根管预备方法对老年人根管再治疗术后疼痛的影响。方法：选择106颗首次根管治疗失败再治疗患牙随机分为实验组与对照组,实验组使用ProTaper Universal再治疗器械（D1、 D2、 D3）去除根管内充填物后, ProTaper（F1、 F2、 F3）进行根管预备,对照组采用不锈钢手用锉去除牙胶后以逐步后退法预备根管,观察两组术后1h、6h、12h、24h、48h、7d VAS自评分值,24h与7d临床评定的疼痛发生率。结果：两组术后疼痛在6h出现,12h达到峰值,此后呈下降趋势,7d时已完全缓解;实验组在疼痛发生期间（6、12、24、48h 4个时间点）VAS自评分值均低于对照组,差异有统计学意义（P值分别为0.000、0.000、0.000、0.004, P〈0.05）;24h临床评定疼痛发生率实验组为11.1%,对照组为34.6%,差异有统计学意义（P=0.042, P〈0.05）;7d时临床评定疼痛发生率实验组为1.85%,对照组为3.85%,差异无统计学意义（P=0.807, P〈0.05）。结论：两种根管预备方法均会引起再治疗术后疼痛,使用ProTaper镍钛系统能有效降低老年人根管再治疗术后疼痛的发生。     

手用ProTaper镍钛器械根管预备后不同充填方法的效果研究

目的:比较手用ProTaper镍钛器械预备根管后不同方法充填后的根尖封闭能力。方法:将手用ProTaper器械预备的45个上颌磨牙单根管牙根,随机分为3组,每组15个。第1组:侧方加压法配合ISO标准牙胶充填;第2组:单尖法配合非ISO标准牙胶充填;第3组:热牙胶垂直加压法配合非ISO标准牙胶充填。牙根经过染色、透明,镜下测量染料渗入深度。结果:第1组和第3组的染料渗入的深度小于第2组,有统计学意义(P<0.05)。结论:手用ProTaper器械预备后的根管采用热牙胶垂直加压法 非ISO牙胶或侧方加压法 ISO牙胶可以获得良好的根尖封闭。     

机用镍钛器械ProTaper用于再治疗根管预备效果的临床评价

目的 评价机用镍钛器械ProTaper预备再治疗根管的临床效果.方法 选择临床上需进行根管再治疗的120颗患牙,随机分为实验组(PT组)和对照组(HF组),每组各60颗.PT组使用机用镍钛器械ProTaper和冠向下技术预备根管,HF组使用标准手用不锈钢H型锉和逐步后退法预备根管.两组均用冷牙胶侧方加压技术充填根管.记录两组根管预备时间和术后并发症出现情况,根据治疗前、中、后的X线片评价根管预备和充填的效果.结果 PT组根管预备时间明显少于HF组,根管成形和充填效果明显优于HF组,但有3例器械分离发生.结论 机用镍铁器械ProTaper应用于根管再治疗预备具有良好的成形和充填效果,且根管预备快速、高效,但应注意预防器械分离.     

不同方法去除根管内充填物的体外试验观察

目的通过体外试验比较根管内充填物的去除比率,评价不同方法去除根管内充填物的效果。方法选择因正畸需要拔除的40颗健康离体单根管前磨牙,根据试验要求预备充填后随机分为2组,实验组用ProTaper Universal再治疗锉+H锉去除根管内充填物,对照组仅用ProTaper Universal再治疗锉去除根管内充填物。处理前后进行CBCT扫描,数据用mimics软件分析,计算根管内充填物去除比率。结果实验组和对照组的根管内充填物去除比率分别为(95.15±2.56)%和(82.73±4.94)%,实验组根管内充填物去除比率高于对照组,差异有统计学意义(P<0.05)。结论在根管再治疗术中去除根管内充填物时,ProTaper Universal再治疗锉与H锉联合使用能取得更满意的效果。     

Efficacy of three rotary NiTi instruments in removing gutta-percha from root canals

Aim To investigate the ability of three rotary nickel–titanium instruments and hand instrumentation to remove gutta‐percha and sealer. Methodology Sixty freshly extracted human single‐rooted teeth, each with one root canal, were instrumented with K‐files and filled using cold lateral compaction of gutta‐percha and AH Plus (Dentsply Detrey, Konstanz, Germany) sealer. The teeth were randomly divided into four groups of 15 specimens each. Removal of gutta‐percha was performed with the following devices and techniques: ProTaper, R‐Endo, Mtwo and Hedström files. The specimens were rendered transparent and the area of remaining filling material on the root canal wall was measured using a computer image analysis program. Statistical analysis was accomplished by Kruskal–Wallis and Mann–Whitney U‐tests with Bonferroni correction for the analysis of residual root filling material and working time. Results The ProTaper group had less filling material inside the root canals than the other groups, but a significant difference was found between only the ProTaper and Mtwo groups (P < 0.05). The retreatment time for Mtwo and ProTaper was significantly shorter compared with R‐Endo and manual instrumentation with Hedström files (P < 0.001). R‐Endo was significantly faster than manual instrumentation (P < 0.001). Conclusions Under the experimental conditions, ProTaper left significantly less gutta‐percha and sealer than Mtwo instruments. Complete removal of materials did not occur with any of the instrument systems investigated.     

Comparison of ProTaper and Mtwo retreatment systems in the removal of resin‐based root canal obturation materials during retreatment

To evaluate the effectiveness of the ProTaper and Mtwo retreatment systems for removal of resin‐based obturation techniques during retreatment. A total of 160 maxillary anterior teeth were enlarged to size 30 using ProTaper and Mtwo rotary instruments. Teeth were randomly divided into eight groups. Resilon + Epiphany, gutta‐percha + Epiphany, gutta‐percha + AH Plus and gutta‐percha + Kerr Pulp Canal Sealer (PCS) combinations were used for obturation. ProTaper and Mtwo retreatment files were used for removal of root canal treatments. After clearing the roots, the teeth were split vertically into halves, and the cleanliness of the canal walls was determined by scanning electron microscopy. Specimens obturated with gutta‐percha and Kerr PCS displayed significantly more remnant obturation material than did specimens filled with resin‐based obturation materials. Teeth prepared with Mtwo instruments contained significantly more remnant filling material than did teeth prepared with ProTaper. ProTaper files were significantly faster than Mtwo instruments in terms of the mean time of retreatment and time required to reach working length. The Resilon + Epiphany and AH Plus + gutta‐percha obturation materials were removed more easily than were the Epiphany + gutta‐percha and Kerr PCS + gutta‐percha obturation materials. Although ProTaper retreatment files worked faster than did Mtwo retreatment files in terms of removing root canal obturation materials, both retreatment systems are effective, reliable and fast.     

Efficacy of different solvents in removing gutta‐percha from curved root canals: A micro‐computed tomography study

The aim of this study was to compare the root filling material that remained after retreatment of curved root canals with chloroform and Endosolv R as solvents. The evaluation employed micro‐computed tomography (CT) imaging. Thirty‐six extracted molar teeth with curved roots were selected. After preparation with ProTaper rotary instruments, the canals were filled with gutta‐percha and AH26 sealer. The teeth were randomly divided into three groups according to solvent used (n = 12) as follows: group 1: chloroform; group 2: Endosolv R; group 3: no solvent (negative control). ProTaper Universal Retreatment files were used to remove each root canal filling and then the self‐adjusting file was applied for two minutes. Preoperative and postoperative micro‐CT images were used to assess the percentage of residual filling material. The mean percentage of residual filling material was quantified. There were no statistically significant differences between the groups in terms of percentage volume of residual root canal filling.     

Efficacy of 2 Reciprocating Systems Compared with a Rotary Retreatment System for Gutta-percha Removal

Introduction

The maximum removal of root canal filling material is essential for successful endodontic retreatment. The purpose of this study was to assess the efficacy of 2 reciprocating systems (Reciproc [VDW, Munich, Germany] and WaveOne [Dentsply Maillefer, Ballaigues, Switzerland]) compared with a nickel-titanium (NiTi) rotary system (ProTaper Universal Retreatment [Dentsply Maillefer]) in the removal of root canal filling material.

Methods

Sixty root canals of extracted human maxillary incisors were prepared using the NiTi ProTaper rotary system with the complementary use of a #40 K-type file and then obturated. The specimens were divided into 3 groups (n = 20) according to the system used for filling removal: group 1: instrument R25 of the Reciproc system, group 2: primary instrument of the WaveOne system, and group 3: NiTi rotary instruments of the ProTaper Universal Retreatment system. The teeth were cleaved longitudinally and photographed under a dental operating microscope with 5 × magnification. Images were transferred to a computer, and residual filling material was quantified using Image Tool software (University of Texas Health Science Center, San Antonio, TX). Results were compared using 1-way analysis of variance (P < .05).

Results

All teeth examined had filling remnants within the canal. No statistically significant difference (P > .05) in residual filling material was observed among the groups, with 4.30% in group 1, 2.98% in group 2, and 3.14% in group 3.

Conclusions

The Reciproc and WaveOne reciprocating systems were as effective as the ProTaper Universal retreatment system for gutta-percha and sealer removal.     

Vitapex糊剂充填根管的临床研究

目的 观察Vitapex糊剂充填根管的疗效，探讨其最适宜的使用方法。方法 将490例慢性根尖周炎随机分为5组，A，B，C，D为实验组，使用Vitapex糊剂，分别用下列方法进行根充；A组，一次法，加牙胶尖；B3组,一次法，不加牙胶尖；C组，二次法，加牙胶尖；D组，二次法，不加牙胶尖。E为对照组，用常规根管充填剂加牙胶法，二次法根充。结果 1年后复查，B组有效率显著低于其他各组（P＜0．05），且A，B，两组的治愈率低于另外三组（P＜0．05）。结论 Vitapex是一种理想的根管充填材料，二次法根充，不加牙胶尖为其最适宜使用方法。     

Efficacy of automated versus hand instrumentation during root canal retreatment: an ex vivo study

Aim To compare automated and manual instrumentation techniques for removing filling material from root canal walls during root canal retreatment. Methodology One hundred extracted human single‐rooted teeth were root filled and stored. Specimens were divided into two groups: group A, Endofill plus gutta‐percha; group B, Sealer 26 plus gutta‐percha. The filling material was removed using the following techniques: group I – Gates–Glidden and K‐type files; group II – ProFile; group III – ProTaper; group IV – K3; group V– Micro Mega Hero 642. The remaining filling debris on the root canal walls were assessed radiographically, images were digitized and analysed using Image ProPlus software. The roots were split for evaluation in a stereomicroscope by epiluminescence and photomicrographs were taken for further analysis. The area covered with filling debris was analysed by means of Student's t‐test to compare the evaluation methods. The student's t‐test was also used to compare the removal of filling materials. An anova test was applied to compare the different techniques (P < 0.05). Results A significant difference occurred between radiographic and photomicrographic evaluation methods (P < 0.05). No significant difference was observed between the filling materials on terms of their removal (P > 0.05). Manual instrumentation left more filling debris on the root canal walls when compared to K3 (P < 0.05) and ProTaper (P < 0.01). Conclusions A photomicrographic method by epiluminescence was more effective than the radiographic method to evaluate filling debris. There was no significant difference between the filling materials in terms of their removal. K3 and ProTaper were more efficient than manual instrumentation.     

3种器械去除椭圆形根管内充填物的效果研究

目的：研究两种镍钛器械和手用不锈钢器械去除椭圆形根管内充填物的效果。方法：45颗具有椭圆形根管的下颌前磨牙经逐步后退法预备、热牙胶垂直加压充填后随机分为3组,分别用ProTaper再治疗器械和ProTaper器械,Mtwo再治疗器械和Mtwo器械,手用H锉和K锉去除牙胶。测量各组中充填物的残留量及各个器械使用的时间。结果：手用器械组充填物的残留量百分比明显低于ProTaper组和Mtwo组,但操作时间高于ProTaper组和Mtwo组。结论：椭圆形根管内,使用机用镍钛器械可以减少操作时间,但是残留的根管充填物较多。     

Efficacy, cleaning ability and safety of different rotary NiTi instruments in root canal retreatment

Aim To evaluate the efficacy, cleaning ability and safety of three different rotary nickel‐titanium instruments with and without a solvent (eucalyptol) versus hand files in the removal of gutta‐percha root fillings. Methodology Eighty extracted single‐rooted anterior teeth were enlarged to size 35 and obturated with laterally condensed gutta‐percha using AHPlus as the sealer. Removal of gutta‐percha was performed with the following devices and techniques: FlexMaster, GT Rotary, ProTaper and Hedström files. All techniques were used with and without the solvent eucalyptol. The following data were recorded: time taken to reach the calculated working length and time required for the removal of gutta‐percha. The teeth were split longitudinally and photographed. Cleanliness of the root canal walls was scored using the projected slides with a total magnification of approximately 70×. Statistical analysis was performed using the two‐way anova (P < 0.001) for the analysis of working time. Results The technique that reached the working length most rapidly was that using ProTaper instruments and eucalyptol (+E), followed by FlexMaster + E, ProTaper, FlexMaster, Hedström files + E, GT Rotary + E, Hedström files, and GT Rotary. No significant differences were found for retreatment with or without a solvent in all groups. ProTaper and FlexMaster worked significantly more rapidly than Hedström files and GT Rotary (anova , P < 0.001). Time for complete removal of gutta‐percha was again shortest with ProTaper + E, followed by FlexMaster + E, ProTaper, FlexMaster, GT Rotary + E, Hedström files + E, Hedström files, and GT Rotary. ProTaper and FlexMaster again worked significantly faster than the other techniques (anova , P < 0.001). There was no visible filling material extruded apically. Root canal cleanliness proved best following the use of FlexMaster + E, and Hedström files + E, followed by ProTaper + E, and GT Rotary + E. Conclusion Under the experimental conditions, FlexMaster and ProTaper NiTi instruments proved to be efficient and time‐saving devices for the removal of gutta‐percha. The use of eucalyptol as a solvent shortened the time to reach the working length and to remove the gutta‐percha, but this was not significant.