手用不锈钢K锉和机用Profile镍钛锉在根管预备中碎屑推出根尖孑L的实验观察与比较

目的观察手用不锈钢K锉和机用Profile镍钛锉用于根管预备时碎屑推出根尖孔的现象，比较其推出的碎屑量并讨论根管预备与碎屑推出根尖孔的关系。方法将60颗离体牙随机分为2组，分别以手用不锈钢K锉或机用Profile镍钛锉进行根管预备。观察碎屑推出根尖孔的过程，收集碎屑后称量，并对2组碎屑收集量进行统计学分析。结果手用K锉组在个别离体牙根管预备过程中先后观察到根尖孔“蠕虫”样、“湿虫”样碎屑推出。2组都观察到“根尖水滴”现象。手用K锉组推出的碎屑量多于机用Profile镍钛锉组，两者差异有统计学意义。结论机用Profile镍钛锉在操作过程中碎屑推出量比手用不锈钢K锉少。     

3种根管预备器械在老年患者离体下颌第一前磨牙根管治疗中的研究

目的 比较手用不锈钢K锉、Protaper机用镍钛锉与M two机用镍钛锉在老年人离体下颌第一前磨牙根管预备的效果。方法 将90颗60岁以上老年人单根管离体下颌第一前磨牙随机分为3组,每组30颗,分别用手用K锉,Protaper机用镍钛锉与M two机用镍钛锉对老年人单根管离体下颌第一前磨牙进行根管预备。观察在预备过程中从根尖孔推出的牙本质碎屑与液体,用预先称量的离心管收集,测量推出根尖孔液体的质量与牙本质碎屑的质量。结果 Protaper机用镍钛锉组推出根尖孔外的牙本质碎屑及冲洗液的质量少于手用K锉组(P<0.05),M two机用镍钛锉组推出根尖孔外的牙本质碎屑及冲洗液的质量少于手用K锉组(P<0.05),并略少于Protaper机用镍钛锉组,差异无统计学意义(P>0.05)。结论 M two机用镍钛锉用于老年人离体下颌第一前磨牙根管预备,可以获得较好的根管预备效果。     

三种根管预备器械在老年人狭窄根管预备时推出根尖孔物质的体外对比研究

目的：比较手用不锈钢K锉、Protaper机用镍钛锉与Mtwo机用镍钛锉在离体老年人狭窄根管预备过程中推出根尖孔物质的质量。方法：将90颗60岁以上老年人狭窄单根管离体下颌中切牙随机分为3个组,每组30颗,分别用手用K锉,Protaper机用镍钛锉与Mtwo机用镍钛锉对离体老年人细窄根管进行预备。预备过程中观察从根尖孔推出的牙本质碎屑与液体,用预先称量的离心管收集,测量推出根尖孔液体的质量与牙本质碎屑的质量。结果：推出根尖孔外的牙本质碎屑及冲洗液的质量：Protaper机用镍钛锉组少于手用K锉组（P〈0.05）;Mtwo机用镍钛锉组少于手用K锉组（P〈0.05）;Mtwo机用镍钛锉组少于Protaper机用镍钛锉组,但差异无统计学意义（P〉0.05）。结论：Mtwo机用镍钛锉与Protaper机用镍钛锉在离体老年人狭窄根管预备过程中推出根尖孔物质的质量均少于手用K锉。     

手用不锈钢K锉和机用Profile镍钛锉在根管预备中碎屑推出根尖孔的实验观察与比较

目的 观察手用不锈钢K锉和机用Profile镍钛锉用于根管预备时碎屑推出根尖孔的现象,比较其推出的碎屑量并讨论根管预备与碎屑推出根尖孔的关系.方法 将60颗离体牙随机分为2组,分别以手用不锈钢K锉或机用Profile镍钛锉进行根管预备.观察碎屑推出根尖孔的过程,收集碎屑后称量,并对2组碎屑收集量进行统计学分析.结果 手用K锉组在个别离体牙根管预备过程中先后观察到根尖孔"蠕虫"样、"湿虫"样碎屑推出.2组都观察到"根尖水滴"现象.手用K锉组推出的碎屑量多于机用Profile镍钛锉组,两者差异有统计学意义.结论 机用Profile镍钛锉在操作过程中碎屑推出量比手用不锈钢K锉少.     

ProTaper手动镍钛锉与ISO标准锉根管预备技术的对比实验研究

目的:比较ProTaper手动镍钛锉与ISO标准手用不锈钢K型锉根管预备技术的效果。方法:将40个含弯曲管的透明塑料模块随机分为两组, 每组20个,A组为ProTaper手动镍钛锉预备组(PT组);B组为手用不锈钢K型锉预备组(SS组)。记录每组根管预备所需的时间,预备后根管形态的变化,以及推出根尖液体和碎屑的量。结果:PT组根管预备所用时间明显小于SS组(P<0. 05);预备后弯曲根管被直化的程度PT组明显小于SS组(P< 0. 05 );预备过程中PT组推出根尖液体和碎屑的量显著少于SS组(P<0. 05)。结论:与传统手用不锈钢锉相比,ProTaper手动镍钛锉在根管预备方面有明显的优越性。     

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。     

可变锥度镍钛锉在树脂弯曲根管中成形效果的观察

目的 比较不锈钢K型锉与可变锥度ProTaper镍钛锉在仿制树脂弯曲根管中的成形效果。方法 将30个仿制树脂根管随机分为3组,分别使用不锈钢K型锉、手用ProTaper锉、机用ProTaper锉预备,记录预备后根管全长内外侧树脂去除量、预备后根管宽度、根管弯曲度变化、根管偏移。结果 与不锈钢K型锉相比,手用和机用Pro Taper锉预备后的根管在根尖外侧和弯曲起始部内侧的树脂去除量较少（P＜0.05）,根管直化度较小（P＜0.05）,无明显根管偏移。结论 ProTaper锉成形效果优于不锈钢K型锉,预备后能形成一个与原形相似、流畅的锥形根管。     

机用镍钛锉根管预备的临床应用研究

目的：比较机用镍钛锉与手用K型锉根管预备的临床应用。方法：将牙位相同、诊断相同，全身情况类似的患者按随机配对原则分入甲乙两组，甲组为镍钛锉预备组；乙组为K型锉预备组，每组50例患者。结果：对于单根管牙齿，使用机用镍钛锉进行根管预备，所用时间与传统手用K型锉根管预备相比无显著差异，对于双根管牙及磨牙而言，采用机用镍钛进行根管预备所用时间明显少于使用传统手用K型锉根管预备，根管预备一周内，使用机用镍钛锉根管预备与传统手用K型锉根管预备术后反应无显著差异，结论：传统手用K型锉预备根管相比，机用镍锉具有省时省力的优点。     

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。     

两种镍钛器械根管预备效果的评价

目的:比较机用ProTaper、MTwo与手用ProTaper根管预备效率和根管壁清洁效果。方法:选择新鲜拔除的下颌第一前磨牙80个,随机分为A、B、C、D 4组,分别采用机用ProTaper、MTwo、手用ProTaper和不锈钢K锉进行根管预备,记录每一根管预备完成总时间;收集根管预备过程中推出根尖孔的碎屑,干燥后称重;采用扫描电镜观察预备后根管壁的清洁效果,并进行碎屑和玷污层评分。结果:B组根管预备时间最少,平均41 s,推出根尖孔的牙本质碎屑量也最少,平均为3.1 mg,与其他各组相比有统计学差异(P<0.05)。D组预备时间最多,平均为204 s,推出根尖孔的碎屑量平均为10.35 mg。A组和C组预备时间分别是68 s,73 s,推出根尖孔的碎屑量各为5.45 mg和5.3 mg。用扫描电镜观察根管壁并对各部位进行碎屑和玷污层的评分,各组冠1/3均比根尖部评分低。在同一部位,B组的评分低于其他3组,D组的评分高于其他3组,差异均有统计学意义(P<0.05)。结论:与ProTaper和传统不锈钢K锉相比,Mtwo器械完成根管预备时间、推出根尖孔的牙本质碎屑量、根管壁清洁度等均优于前两者。     

Apical extrusion of debris and irrigants using two hand and three engine-driven instrumentation techniques

AIM: To evaluate the weight of debris and irrigant volume extruded apically from extracted teeth in vitro after endodontic instrumentation using the balanced force technique, a hybrid hand instrumentation technique, and three engine-driven techniques utilizing nickel-titanium instruments (ProFile .04, Quantec 2000 and Pow-R). METHODOLOGY: Five groups of 20 extracted human teeth with single canals were instrumented using one or other of five techniques: balanced force, hybrid, Quantec 2000, ProFile .04, or Pow-R. Debris extruded from the apical foramen during instrumentation were collected into preweighed 1.5 mL tubes. Following instrumentation, the volume of extruded irrigant fluid was determined by visual comparison to control centrifuge tubes filled with 0.25 mL increments of distilled water. The weight of dry extruded dentine debris was also established. RESULTS: Overall, the engine-driven techniques extruded less debris than the manual ones. However, there was no statistical difference between the balanced force technique and the engine-driven methods. The volume of irrigant extruded through the apex was directly associated with the weight of extruded debris, except within the ProFile group. The hybrid technique was associated with the greatest extrusion of both debris and irrigant. CONCLUSIONS: Overall, the engine-driven nickel-titanium systems were associated with less apical extrusion.     

Apical extrusion of debris by manual and mechanical instrumentation

The aim of the present study was to assess the presence of apically extruded debris and evaluate the influence of canal curvature on the amount of debris produced by manual and mechanical techniques. Forty single-rooted mature teeth with 15 to 30 degree of root canal curvature were selected. The presence of only one foramen was confirmed using a magnifying lens. A size 15 K-file was placed up to the apical foramen to determine the patency. Working length was determined with the same instrument, 1 mm short of the foramen. According to the employed technique, the groups were labeled as follows: Group 1 - Manual instrumentation with Mor-flex files; Group 2 - Mechanical instrumentation with Cursor and Mor-flex files; Group 3 - Manual instrumentation with Flexi-cut files; Group 4 - Mechanical instrumentation with Cursor and Flexi-cut files. During instrumentation, the root canals were irrigated with 20 mL. Debris extruded through the apical foramen was collected using the Myers and Montgomery technique. The values (in mg) were: Group 1: 0.422 +/- 0.683; Group 2: 0.688 +/- 0.795; Group 3: 0.409 +/- 0.323; Group 4: 0.810 +/- 0.708. Data were analyzed statistically by ANOVA at 5% significance level. There was no statistically significant difference among the groups (p<0.05). No statistically significant differences were found between slight and moderate curvatures in terms of the amount of extruded debris (p>0.05).     

Apically-extruded debris using the ProTaper system

The purpose of this in vitro study was to determine the quantity of debris and irrigant extruded apically using the ProTaper system compared to ProFiles and K-Flexofiles. Thirty-six mesio-buccal root canals of human mandibular molars were selected and divided into three groups of twelve canals. Two groups were instrumented with ProFiles and ProTapers according to the manufacturer's instructions. The other group was instrumented with K-Flexofiles using the step-back technique. A standard amount of irrigant was used for each canal. Apically-extruded debris and irrigant was collected in pre-weighed vials. The mean weight of extruded debris and irrigant for each group was statistically analysed using Student's t-test and one-way ANOVA. All instrumentation techniques produced extruded debris and irrigant. Although the mean amount of extrusion with the step-back technique was higher than the two rotary systems, there was no significant difference between the three groups (p > 0.05). NiTi rotary systems were associated with less apical extrusion, but were not significantly better than hand file instrumentation. All techniques extruded debris.     

WaveOne单支锉的根管预备效果及碎屑推出根尖孔评价

目的评价新型往复运动系统Wave One单支锉的根管预备效率及预备过程中,根尖部碎屑排出情况。方法选择40颗单根管下颌前磨牙,随机分成4组,分别用K-File、BLx、Pro Taper Universal及Wave One四种器械根管预备,收集从根尖孔排出的牙本质碎屑,称重,再结合各组根管的预备时间,进行综合比较评价。结果 K-File组产生的根尖推出碎屑量最多,Waveone组次之,除BLx组与Pro Taper组之间无显著差异(P>0.05),其他各组之间存在统计学差异(P<0.05)。Wave One组所需预备时间最短,其次是BLx组、Pro Taper组,K-File组最慢,各组间差异有统计学意义(P<0.05)。结论 Wave One在根尖推出碎屑量方面,相较于手用K-File具有优势,但较其他两种传统的机用镍钛器械多。与其他三种器械相比,Wave One具有最佳的根管预备效率。     

A comparison of weights of debris extruded apically by conventional filing and Canal Master techniques

Sixty extracted human teeth were divided into three groups of 20 each. Apically extruded debris and irrigant were collected, dried, and weighed by the following three instrumentation techniques: (a) group 1, filing 1 mm short of the foramen; (b) group 2, Canal Master instrumentation to the foramen; and (c) group 3, filing to the foramen (for a relative comparison). The results indicated that all three groups were significantly different from one another. Group 1 had the least amount of debris extruded. Of the two groups instrumented to the foramen, group 3 had twice as much debris extruded as group 2. An apical dentinal plug was frequently found in group 1 and was probably a major reason why this group had the least amount of extruded debris. The significance of this dentinal plug and possible indications for instrumentation to the foramen are discussed.     

Apical extrusion of intracanal bacteria following use of various instrumentation techniques

Aim To evaluate the number of bacteria extruded apically from extracted teeth ex vivo after canal instrumentation using a manual technique and three engine‐driven techniques utilizing nickel–titanium instruments (K3, RaCe, and FlexMaster). Methodology Seventy extracted human mandibular premolar teeth with similar dimensions were used. Access cavities were prepared and root canals were then contaminated with a suspension of Enterococcus faecalis and then dried. The contaminated roots were divided into four experimental groups of 15 teeth each and one control group of 10 teeth. G1. RaCe group: the root canals were instrumented using RaCe instruments. G2. K3 group: the root canals were instrumented using K3 instruments. G3. FlexMaster group: the root canals were instrumented using FlexMaster instruments. G4. Manual technique group: the root canals were instrumented using K‐type stainless steel instruments. G5. Control group: no instrumentation was attempted. Bacteria extruded from the apical foramen during instrumentation were collected into vials. The resultant microbiological samples were removed from the vials and then incubated in culture media for 24 h. The number of colony‐forming units (CFU) was determined for each sample. The data obtained were analysed using the Kruskal–Wallis one‐way analysis of variance and Mann–Whitney U‐tests, with α = 0.05 as the level for statistical significance. Results There was a significant difference between experimental‐control and engine‐driven‐manual technique groups (P < 0.05). The manual technique was associated with the greatest extrusion of microorganism. Conclusions All instrumentation techniques extruded intracanal bacteria apically. No significant difference was found in the number of CFU among the engine‐driven techniques; manual techniques extruded significantly more microorganisms.     

A comparison between a smooth wire and a K-file in removing artificially placed dentine debris from root canals in resin blocks during ultrasonic irrigation

AIM: To compare the efficacy of a smooth wire with a conventional K-file, in removing dentine debris from grooves in root canals made in resin blocks, during ultrasonic irrigation. METHODOLOGY: Each resin block containing a standard simulated canal was split longitudinally through the canal, forming two halves. In one canal wall, a standard groove 4 mm in length, 0.2 mm in width and 0.5 mm in depth was cut 2-6 mm from the apical end of the canal, to simulate uninstrumented canal extensions. Each groove was filled with fresh dentine debris mixed with 2% NaOCl to simulate a situation when dentine debris accumulates in uninstrumented canal extensions. Each canal was reassembled by joining the two halves of the resin block by means of wires and sticky wax. In each canal ultrasonic irrigation was performed for 3 min using 2% NaOCl as irrigant. In one group (n = 20) a conventional K-file size 15 was used. In the other group (n = 20) a smooth wire was used which had the same length and diameter as the size 15 K-file. Before and after irrigation, images of each half of the canal with a groove were taken, using a microscope and a digital camera, after which they were scanned into a PC as TIFF images. The quantity of dentine debris in the groove was evaluated using a scoring system: the higher the score, the larger the amount of debris remaining. The score data were analysed by means of the Mann-Whitney U-test. RESULTS: After ultrasonic irrigation, the debris was completely removed from the groove in 35 canals (87.5%), and there was no significant difference between the groups (P = 0.429). CONCLUSIONS: Using a smooth wire during ultrasonic irrigation is as effective as a size 15 K-file in removal of artificially placed dentine debris in grooves in simulated root canals in resin blocks.     

Laser-activated irrigation within root canals: cleaning efficacy and flow visualization

Aim  To test ex vivo the efficiency of laser-activated irrigation in removing dentine debris from the apical part of the root canal and to visualize in vitro the fluid dynamics during the activation of the irrigant by laser, using high-speed imaging at a relevant timescale.
Methodology  Root canals with a standardized groove in one canal wall filled with dentine debris were irrigated with syringe irrigation, ultrasonically or laser-activated irrigation (LAI) using 2% sodium hypochlorite as irrigant. The quantity of dentine debris after irrigation was determined. Visualization of the fluid dynamics during activation was achieved using a high-speed camera and a glass model.
Results  Laser-activated irrigation was significantly more effective in removing dentine debris from the apical part of the root canal than passive ultrasonic irrigation or hand irrigation when the irrigant was activated for 20 s.
Conclusions  The in vitro recordings suggest that streaming, caused by the collapse of the laser-induced bubble, is the main cleaning mechanism of LAI.     

声波手机与机用镍钛器械根管预备过程中根尖冲洗液及碎屑溢出比较研究

评价机用镍钛器械与声波手机根管预备过程中冲洗液及碎屑溢出根尖情况。 方法    选取2012年10月至2014年1月在中国医科大学附属口腔医院口腔外科门诊因正畸治疗需要或牙周炎症拔除的单根管离体牙（长度与弯曲度相近）40颗作为研究样本,随机分为ProTaper组（使用机用ProTaper镍钛锉进行根管预备）和Sonic handpiece组（使用MM1500声波手机及其配套的Rispisonic和Shaper锉进行根管预备）,并将离体牙安装到碎屑及液体收集装置。在根管预备过程中每换用一号器械时,用1 mL次氯酸钠溶液进行根管冲洗,用EP管收集根尖溢出冲洗液及碎屑,称重;恒温箱内干燥5 d后再次称重。比较两组根尖冲洗液及碎屑溢出情况。 结果    根尖冲洗液溢出量的中位数：ProTaper组为116.24 mg,Sonic handpiece组为13.76 mg,两组差异有统计学意义（P < 0.05）。根尖碎屑溢出量的中位数：ProTaper组为4.87 mg,Sonic handpiece组为0.63 mg,两组差异有统计学意义（P < 0.05）。结论    使用声波手机在根管预备时产生的根尖冲洗液及碎屑溢出均明显少于使用机用镍钛器械;声波手机具有较好的临床应用前景。     

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??Objective    To evaluate and compare the amount of debris and irrigant extrusion quantitatively by using rotary nickel-titanium ??Ni-Ti?? instrument and sonic handpiece in root canal preparation. Methods    Forty freshly extracted human teeth were selected??which were with single canals??having similar canal length and curvature??due to orthodontics therapy and periodontitis in Department of Oral and Maxillofacial Surgery of China Medical University Stomatology Hospital during October 2012 to January 2014. They were separated into two groups based on Ni-Ti instruments ProTaper and sonic handpiece and mounted in a debris collection apparatus. After each instrument change??1 mL of NaClO was used as the irrigant and the amount of irrigant extruded was measured by EP tube. The EP tube was weighed using an electronic microbalance to determine its weight. After drying in an incubator for five days??the EP tube was weighed again. Compare the amount of debris and irrigant extrusion quantitatively. Results    The median of the amount of irrigant??in the group of ProTaper it was 116.24 mg??in the group of sonic handpiece it was 13.76 mg. The rotary Ni-Ti instrumentation techniques extruded significantly more irrigant than sonic handpiece??P < 0.05??. The median of the amount of debris??in the group of ProTaper it was 4.87 mg??in the group of sonic handpiece it was 0.63 mg. The rotary Ni-Ti instrumentation techniques extruded significantly more debris than sonic handpiece??P < 0.05??. Conclusion    The sonic handpiece extrudes significantly less irrigant and debris than the rotary Ni-Ti instrumentation techniques. It has a good clinical application prospects.