A comparative study of root canal preparation using FlexMaster and HERO 642 rotary Ni-Ti instruments

Aim To compare several parameters of root canal preparation using two different rotary nickel–titanium (Ni–Ti) instruments: FlexMaster (VDW, Munich, Germany) and HERO 642 (Micro‐Mega, Besançon, France). Methodology Fifty extracted human mandibular molars with root canal curvatures between 20 and 40° were embedded into a muffle system. All root canals were prepared to size 45 using a high‐torque motor with two different Ni–Ti instruments, FlexMaster and HERO 642. In both groups, irrigation was performed with 2 mL NaOCl (3%) after each instrument size. RC‐Prep (Premier, Philadelphia, USA) was used as a chelating agent with each instrument. The following parameters were evaluated: straightening of curved root canals, postoperative root canal diameter, working safety (file fractures, perforations, apical blockages, loss of working length), cleaning ability and working time. Statistical analysis was performed using the Wilcoxon's test (P < 0.05) for straightening and Fishers's exact test (P < 0.05) for comparison of cross‐sections, contact between pre‐ and postoperative diameter, root canal cleanliness and working time. Results Both Ni–Ti systems maintained the curvature well: the mean degree of straightening was 0.6° for FlexMaster and 0.5° for HERO 642. One file was fractured with the FlexMaster system, but further procedural incidents were not recorded. Following preparation with FlexMaster, 18% of the root canals had a round diameter, 53% an oval diameter and 29% an irregular diameter; HERO 642 preparations resulted in a round diameter in 25%, oval shape in 47% and irregular cross‐sections in 28% of the cases. Mean working time was shorter for HERO 642 (66.0 s) than for FlexMaster (71.1 s). Cleanliness of the root canal walls was investigated under the SEM using 5‐score indices for debris and smear layer. For debris, HERO 642 and FlexMaster achieved 73 and 70% scores of 1 and 2, respectively. The results for smear layer were similar: HERO 642 and FlexMaster achieved 33 and 26% scores of 1 and 2, respectively. Significant differences between the two systems were not detected for any of the parameters evaluated. Conclusions Both systems respected original root canal curvature well and were safe. Both systems failed to remove debris and smear layer in the majority of the cases.     

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.     

Comparison of root canal preparation with two rotary NiTi instruments: ProFile .04 and GT Rotary

AIM: To compare root canal preparation using ProFile .04 and GT Rotary nickel-titanium instruments (both Dentsply Maillefer, Ballaigues, Switzerland). METHODOLOGY: Fifty extracted mandibular molars with mesial root canal curvatures between 20 and 40 degrees were randomly divided into two groups and embedded in a muffle system. All root canals were prepared to size 45 using ProFile .04 or GT rotary instruments. The following parameters were evaluated: straightening of root canal curvature, postoperative root canal cross-section, cleaning ability, safety issues and working time. RESULTS: Both NiTi systems maintained curvature well; the mean degree of straightening was <1 degrees . The majority of the root canals prepared with ProFile .04 (80.8%) and GT (84.0%) postoperatively showed a round or oval cross-section. For debris, ProFile .04 and GT rotary achieved 67.1% and 71.6% scores of 1 and 2, respectively. Concerning the coronal region statistical analysis showed a better result for GT than for ProFile .04. For the middle and apical thirds of the root canals, results did not differ significantly. None of the two systems completely removed smear layer. Ten procedural incidents occurred with ProFile .04 compared with five with GT. Mean working time was shorter for ProFile .04 (131.8 s) than for GT (143.7 s); the difference was not significant. CONCLUSIONS: Both systems respected original root canal curvature well and were safe to use. Smear layer removal was not satisfactory with either systems.     

A comparative study of root canal preparation with NiTi-TEE and K3 rotary Ni-Ti instruments

Aim To evaluate and compare several parameters of curved root canal preparation using two different Ni‐Ti systems: NiTi‐TEE (Sjöding Sendoline, Kista, Sweden) and K3 (Sybron Endo, Orange County, CA, USA). Methodology Fifty extracted mandibular molars with mesial root canal curvatures ranging from 20 to 40° were divided into two groups. In one group, 50 root canals were instrumented using NiTi‐TEE files to an apical size 30; 0.04 taper (the largest available size at the time of this study). In the other group, 50 root canals were prepared with K3 instruments to an apical size 45; 02 taper. Both systems were used in a crowndown manner, with copious NaOCl (3%) irrigation and a chelating agent (Calcinase Slide, lege artis, Dettenhausen, Germany), employing torque‐controlled motors. For assessment of shaping ability, pre‐ and postinstrumentation radiographs and cross‐sectional photographs of canals were taken and changes in canal curvature and root canal diameter documented. Cleaning ability was evaluated by investigating specimens of the apical, medial and coronal third of the root canal wall under a scanning electron microscope using 5‐score indices for debris and smear layer. Procedural errors (instrument separations, perforations, apical blockages, loss of working length) and working time were recorded. Nonparametric anova was used to compare straightening of canal curvatures, canal cross‐sections and canal wall cleanliness (P < 0.05), whereas working time was analysed using the parametric anova (P < 0.05). Results Both Ni‐Ti systems maintained curvature well: the mean degree of straightening was 0.2° for NiTi‐TEE and 0.4° for K3 with no statistical significance between the groups. Post‐instrumentation cross‐sections of the root canals revealed an acceptable contour (round or oval) in 50.6% of cases for the NiTi‐TEE group and in 65.3% of cases for the K3 group. The difference was not significant. The SEM investigation of canal walls showed equally good debris removal for both systems: NiTi‐TEE prepared canal walls in 74.7% of cases with scores I and II; K3 achieved these scores in 78.7% of cases. For smear layer, NiTi‐TEE and K3 only received good scores (I and II) in 38.7% and 40% of canal wall specimens, respectively. For both parameters, no significant differences were found between groups. File fractures did not occur, but loss of working length was observed in one case following the preparation with NiTi‐TEE and in three cases during K3 instrumentation. Mean working time was significantly shorter for NiTi‐TEE (170 s) than for K3 (208 s). Conclusions Both systems maintained original canal curvature well and were safe to use. Whilst debridement of canals was considered satisfactory, both systems failed to remove smear layer sufficiently.     

Comparison of root canal preparation using RaCe and ProTaper rotary Ni-Ti instruments

AIM: To compare various parameters of root canal preparation using RaCe (FKG Dentaire, La-Chaux-de-Fonds, Switzerland) and ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) nickel-titanium (Ni-Ti) instruments. METHODOLOGY: Fifty extracted mandibular molars with mesial root canal curvatures between 20 degrees and 40 degrees were embedded in a muffle system. All root canals were prepared to size 30 using RaCe or ProTaper rotary instruments in low-torque motors with torque control and constant speed of 300 r.p.m. (ProTaper with ATR Tecnika, Advanced Technology Research, Pistoia, Italy; RaCe with EndoStepper, S.E.T., Olching, Germany). In both groups irrigation was performed with 2 mL NaOCl (3%) after each instrument size. Calcinase-Slide (lege artis, Dettenhausen, Germany) was used as a chelating agent with each instrument. The following parameters were evaluated: straightening of curved root canals, postoperative root canal cross-sections, safety issues and working time. Cleanliness of the root canal walls was investigated under the SEM using 5-score indices for debris and smear layer. Statistical analysis was performed using the following tests: Wilcoxon's test for straightening and working time was used (P < 0.05); Fisher's exact test for comparison of cross-sections and root canal cleanliness (P < 0.05). RESULTS: Both Ni-Ti systems maintained curvature well; the mean degree of straightening was less than 1 degrees for both systems. Following preparation with RaCe, 49% of the root canals had a round or oval diameter and 50% an irregular diameter, ProTaper preparations resulted in a round or oval diameter in 50% of the cases. For debris, RaCe and ProTaper achieved 47 and 49% scores of 1 and 2, respectively; there was no significant difference. For smear layer, RaCe and ProTaper achieved 51 and 33% scores 1 and 2, respectively; no statistically significant differences were apparent for the coronal and middle sections of the root canals, but RaCe performed significantly better in the apical region (Fisher's exact test, P = 0.0392). Two roots lost working length with RaCe instruments, whilst ProTaper preparation resulted in two roots loosing working length and one fractured instrument. Mean working time was shorter for ProTaper (90.9 s) than for RaCe (137.6 s); the difference was significant (Wilcoxon's test, P = 0.011). CONCLUSIONS: Both systems respected original root canal curvature well and were safe to use. Cleanliness was not satisfactory for both systems.     

Comparative study of root-canal preparation using Lightspeed and Quantec SC rotary NiTi instruments

AIM: To compare several parameters of root-canal preparation using two different rotary nickel-titanium (NiTi) instruments: Lightspeed (Lightspeed Inc, San Antonio, TX, USA) and Quantec SC (Tycom, Irvine, USA). METHODOLOGY: Fifty extracted mandibular molars with root-canal curvatures between 20 degrees and 40 degrees were embedded into a muffle system. All root canals were prepared to size 45 followed by a stepback in 1-mm increments to size 70 (Lightspeed) or 45 (Quantec SC), using a high-torque motor at 1300 or 350 r.p.m. respectively. In both groups, irrigation was performed with 2 mL NaOCl (3%) after each instrument size. RC-Prep (Premier, PA, USA) was used as a chelating agent. The following parameters were evaluated: straightening of curved root canals, postoperative root-canal diameter, working safety (instrument fractures, perforations, apical blockages, loss of working length (WL)), cleaning ability and working time. Cleanliness of the root-canal walls was investigated under SEM using 5-score indices for debris and smear layer. Statistical analysis was performed using the Wilcoxon's test (P < 0.05) for straightening and Fisher's exact test (P < 0.05) for comparison of cross-sections, contact between pre- and postoperative diameter, root-canal cleanliness and working time. RESULTS: Both NiTi systems maintained the curvature well: the mean degree of straightening was 1.8 degrees for Lightspeed and 1.7 degrees for Quantec SC; differences were not significant. Procedural incidents occurred with Quantec SC in 12 root canals (three fractures, four apical blockages and five cases of loss of WL), preparation with Lightspeed resulted in five fractures, one apical blockage and five cases of loss of WL (11 incidents). Following preparation with Lightspeed, 55.5% of the root canals had a round diameter, 25% an oval and 19.5% an irregular diameter; Quantec SC preparations resulted in a round diameter in 51.5%, oval shape in 33.3% and irregular cross-sections in 15.2% of the cases. Mean working time was similar for Quantec SC (161 s) and Lightspeed (155 s); the difference was not significant. For debris, Lightspeed and Quantec achieved 64 and 63% for scores 1 and 2, respectively. For smear layer, Lightspeed and Quantec achieved only 13.3 and 27.4% for scores 1 and 2, respectively. Differences were not significant for either debris or smear layer. CONCLUSIONS: Both systems respected original root-canal curvature well and prepared acceptable diameter forms. The cleaning ability was judged not satisfactory for both systems. Both systems showed deficiencies in working safety.     

Comparative study of six rotary nickel-titanium systems and hand instrumentation for root canal preparation

Aim To compare ex vivo various parameters of root canal preparation using a manual technique and six different rotary nickel–titanium (Ni–Ti) instruments (FlexMaster, System GT, HERO 642, K3, ProTaper, and RaCe). Methodology A total of 147 extracted mandibular molars were devided into seven groups (n = 21) with equal mean mesio‐buccal root canal curvatures (up to 70°), and embedded in a muffle system. All root canals were prepared to size 30 using a crown‐down preparation technique for the rotary nickel–titanium instruments and a standardized preparation (using reamers and Hedströem files) for the manual technique. Length modifications and straightening were determined by standardized radiography and a computer‐aided difference measurement for every instrument system. Post‐operative cross‐sections were evaluated by light‐microscopic investigation and photographic documentation. Procedural errors, working time and time for instrumentation were recorded. The data were analysed statistically using the Kruskal–Wallis test and the Mann–Whitney U‐test. Results No significant differences were detected between the rotary Ni–Ti instruments for alteration of working length. All Ni–Ti systems maintained the original curvature well, with minor mean degrees of straightening ranging from 0.45° (System GT) to 1.17° (ProTaper). ProTaper had the lowest numbers of irregular post‐operative root canal diameters; the results were comparable between the other systems. Instrument fractures occurred with ProTaper in three root canals, whilst preparation with System GT, HERO 642, K3 and the manual technique resulted in one fracture each. Ni–Ti instruments prepared canals more rapidly than the manual technique. The shortest time for instrumentation was achieved with System GT (11.7 s). Conclusions Under the conditions of this ex vivo study all Ni–Ti systems maintained the canal curvature, were associated with few instrument fractures and were more rapid than a standardized manual technique. ProTaper instruments created more regular canal diameters.     

镍钛机用器械结合超声仪预备老年磨牙根管的临床研究

目的探讨镍钛机用器械Hero642结合超声根管治疗仪EMS在磨牙根管治疗术中的应用效果。方法选取患牙髓炎或根尖周炎的磨牙122例,随机分为两组,对照组采用传统不锈钢根管锉手工预备根管,试验组采用镍钛机用器械Hero642结合EMS超声根管治疗仪进行根管预备,记录根管预备时间及根管预备术后反应。结果试验组的根管预备时间短于对照组,术后疼痛发生率也低于对照组,差异均有统计学意义。结论镍钛机用器械Hero642结合超声根管治疗仪EMS可有效地提高根管预备效率,并减少术后疼痛。     

机用和手用镍钛器械对不同弯曲度根管预备后的碎屑及预备效率的研究

目的 研究比较机用镍钛锉ProTaper Gold和手用镍钛锉ProTaper对不同弯曲度根管预备后的根尖碎屑推出量及预备效率.方法 将纳入标准收集的离体牙根管按不同的弯曲度(小于15°、20°～35°)分为2组,每组再按不同类型的镍钛器械(PTG、PTH)将其随机分为2个亚组(n=15).PTG组采用ProTaper...     

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。     

ProFile ProTaper镍钛根管器械与不锈钢K锉预备弯曲根管的比较研究

目的：比较ProFile镍钛机用根管器械，ProTaper镍钛手用根管器械和不锈钢K锉用于弯曲根管预备时的根管拉直和根尖偏移，为ProFile和ProTaper的临床应用提供实验依据。方法：将正畸前减数拔除的30个下颌第一前磨牙随机分为3组，分别用不锈钢K锉、ProTaper镍钛手用根管器械、ProFile镍钛机用根管器械做根管预备，分析评价其根管拉直和根尖偏移情况。结果：不锈钢K锉组的根管拉直、根尖偏移显著大于ProTaper和ProFile预备组。结论：ProFile和ProTaper镍钛根管预备器械与传统的不锈钢器械相比更适合弯曲根管的根管预备。     

ProTaper机用镍钛锉根管预备的临床效果分析

目的 评价ProTaper机用镍钛锉根管预备的临床效果。方法 选择300颗患牙（638个根管）随机分为ProTaper组和K锉组,分别用ProTaper机用镍钛锉和K锉进行根管预备,采用χ2检验比较根管预备后的疼痛反应、根管充填效果及器械分离情况。结果 ProTaper组根管预备后疼痛发生率为6.00%,较K锉组的根管预备后疼痛发生率（26.67%）少（P<0.01）,ProTaper组根管恰填率为93.77%,较K锉组（88.64%）高（P<0.05）,两组间的器械分离则无统计学差异（P＞0.05）。结论 ProTaper机用镍钛锉能有效降低根管预备后疼痛的发生和提高根管充填质量,而且较为安全。     

控制记忆型镍钛锉HyFlexCM根管预备的临床效果分析

目的 评价控制记忆型镍钛锉HyFlex CM根管预备的临床疗效。方法 选择拟行根管治疗的300颗下颌第一磨牙和第二磨牙随机分为HyFlex CM组和Protaper组,分别用HyFlex CM机用镍钛锉和Protaper锉进行根管预备,采用卡方检验比较2组在根管预备时间、根管预备后的疼痛反应、根管充填效果、器械分离率等方面的差异。结果 平均预备时间HyFlex CM组为21.7 min、Protaper组为22.5 min（P〉0.05）;疼痛发生率HyFlex CM组为4%,Protaper组为3%（P〉0.05）;根管恰填率HyFlex CM组为95.10%,Protaper组为96.18%（P〉0.05）;HyFlex CM组发生1例器械分离,Protaper组发生6例器械分离。结论 HyFlex CM同样能有效降低根管预备后疼痛的发生,也能更好地保持根管解剖的初形,明显减少器械分离的发生,从而提高了根管充填的效率和质量。     

不同锥度机用镍钛器械预备对根管壁清洁率的影响

目的:研究不同锥度机用镍钛根管器械对根管管壁清洁率的影响。方法:选用80个单根管离体牙,随机分成4组,A组成形至30/0.04,B组成形至30/0.06,C组成形至30/0.08,而D组成形至30/0.10。纵劈各组根管,用扫描电镜观察根管壁的清洁度,并进行两两比较。结果:根冠1/3部位,4组的的差异无明显统计学意义(p>0.05);根中1/3部位,两两比较,4组的的差异有统计学意义(p<0.05);但B、C、D3组之间无明显统计学差异;根尖1/3部位,A与B相比,B与C相比,其差异均有统计学意义(p<0.05),但C和D组相比没有统计学意义(p>0.05)。结论:根管预备时增加机用镍钛器械的预备锥度,可提高根管壁清洁率。     

镍钛旋转锉在老年人根管治疗中应用

目的:探讨机用镍钛器械ProTaper在老年患者根管治疗中应用的临床效果。方法:选取临床上因牙髓炎及根尖周炎需要进行根管治疗的老年患者46例,患牙56颗(94个根管),运用冠向下技术,采用机用镍钛器械ProTaper进行根管预备,热牙胶垂直加压技术充填根管。记录根管预备所需要的时间及器械折断的数量,根据治疗前、中及根充后的X线片评价预备及根充效果。结果:所有患者的根管预备锥度流畅度好,根管形态及工作长度无改变,无1例发生器械分离。结论:在老年患者的根管治疗中,使用机用镍钛器械ProTaper进行根管预备,可以获得比较好的临床效果。     

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。     

Ex vivo study on root canal instrumentation of two rotary nickel–titanium systems in comparison to stainless steel hand instruments

Aim  To investigate instrumentation time, working safety and the shaping ability of two rotary nickel–titanium (NiTi) systems (Alpha System and ProTaper Universal) in comparison to stainless steel hand instruments.
Methodology  A total of 45 mesial root canals of extracted human mandibular molars were selected. On the basis of the degree of curvature the matched teeth were allocated randomly into three groups of 15 teeth each. In group 1 root canals were prepared to size 30 using a standardized manual preparation technique; in group 2 and 3 rotary NiTi instruments were used following the manufacturers' instructions. Instrumentation time and procedural errors were recorded. With the aid of pre- and postoperative radiographs, apical straightening of the canal curvature was determined. Photographs of the coronal, middle and apical cross-sections of the pre- and postoperative canals were taken, and superimposed using a standard software. Based on these composite images the portion of uninstrumented canal walls was evaluated.
Results  Active instrumentation time of the Alpha System was significantly reduced compared with ProTaper Universal and hand instrumentation ( P  <   0.05; anova ). No instrument fractures occurred in any of the groups. The Alpha System revealed significantly less apical straightening compared with the other instruments ( P  <   0.05; Mann–Whitney U test). In the apical cross-sections Alpha System resulted in significantly less uninstrumented canal walls compared with stainless steel files ( P  <   0.05; chi-squared test).
Conclusion  Despite the demonstrated differences between the systems, an apical straightening effect could not be prevented; areas of uninstrumented root canal wall were left in all regions using the various systems.     

ProTaper机用镍钛锉预备根管的临床安全使用次数探讨

目的 通过对ProTaper机用镍钛锉（后简称ProTaper锉）预备根管流程的改良,在确保临床疗效的同时,提高临床安全使用次数。方法 选取患牙162颗,其中前牙、前磨牙和磨牙分别为23颗、28颗和111颗,按照探查根管、确定工作长度、初步疏通根管、GG钻预敞开根管上段以及ProTaper锉扩大成形的流程预备根管,侧方加压充填根管,通过术前、中、后X片来评价根管预备和充填的效果。结果 ProTaper锉能很好的维持根管的形态,术后反应少而轻。使用的9套ProTaper锉最多预备51个根管,最少预备35个根管,平均预备41个根管;SX、S1、S2、F1、F2、F3分别平均用了19.4、43.3、43.3、43.2、38.3、6.7个根管;有2套锉最终出现F1折断,2套出现S1和F1解螺旋,其余5套表现为锉柄、锉刃的老化。结论 根管预备流程的改良、熟练的操作、详细的使用记录和妥善保管是提高ProTaper锉安全使用次数的保障,建议使用ProTaper锉混合预备前后牙根管总数不超过35个。     

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。     

机用镍钛器械预备清理根管效果的定量分析

目的:比较机用镍钛根管预备器械ProFile与手动器械对弯曲根管的清理效果.方法:3组弯曲根管分别进行ProFile、手动不锈钢RT锉、NiTiflex锉预备.立体显微镜下观察根管纵截面并采用图象分析软件Scion Image 1.62定量分析根管碎屑分布比例与根尖栓塞的形成.结果:ProFile组碎屑指数小于其他两组;碎屑栓发生率各组无显著性差异,但与根管弯曲部位相关.结论:ProFile器械采用冠根向深入法对弯曲根管碎屑的清理优于手动器械,但仍应注意弯曲位于根尖1/3段者易发生根尖阻塞.