根管预备后超声冲洗的临床研究

目的 对不同方法根管预备后超声冲洗进行临床评估。方法 将121例患者144颗患牙，随机分成四组：手用不锈钢K锉组；手用不绣钢K锉＋超声冲洗组；机用不锈钢K锉组；机用不绣钢K锉＋超声冲洗组。手用不绣钢K锉采用逐步深入法预备根管，机用不绣钢K锉采用逐步后退法预备根管。比较四组根管预备后疼痛发生情况率、根管充填质量、根尖偏移和倜枝根管充填情况，以及根管充填一年疗效观察。结果各组根管预备后疼痛无显著性差异（P〉0．05）。超声组侧枝根管充填率高于单纯手用和机用组。术后一年复查98颗，相应各组无显著性盖异（P〉0．05）。结论 根管预备后超声冲洗，对降低术后疼痛及提高临床治疗有效率无明显效果；但可以提高侧枝根管充填率。     

3种器械预备弯曲根管的比较研究

目的 :比较不锈钢K型锉、镍钛合金K型锉以及镍钛合金X型锉预备弯曲根管的根尖偏移。方法 :将 4 5个 15°～ 35°的弯曲前磨牙根管按弯曲度排序后均匀分成 15个区组 ,每区组 3个根管 ,再随机分配至3个不同器械处理组。根管冠部用GG钻预处理后 ,行常规法预备根管 ,拍摄数字化X线片记录预备至不同锉号时根管器械尖端所在位置。最后 ,将根管预备前后器械尖端相应位置描记后 ,在立体显微镜下测量不同锉号根管预备后的根尖偏移。结果 :3组标本的根尖偏移均随锉号的增大而增大 ,# 35和 # 4 0不锈钢K型锉根管预备所致的根尖偏移与另外两组标本相比有显著性差异 (P <0 .0 5 ) ,另有两个标本根管侧穿 ;两组镍钛合金锉之间的根尖偏移无显著性差异 (P >0 .0 5 )。结论 :对于弯曲根管 ,用镍钛合金锉预备 ,其效果优于不锈钢锉。     

EDTA凝胶在钙化根管预备中的应用

目的：观察EDTA凝胶辅助K型锉和ProTaper手用镍钛锉在钙化阻塞根管预备中的临床效果。方法：选取根管细小钙化患牙68颗158个根管,随机分为两组,实验组EDTA凝胶辅助K型锉和ProTaper手用镍钛锉预备根管82个,对照组K型锉加ProTaper手用镍钛锉预备根管76个,根据临床检查和X线片比较两组根管预备效果。结果：实验组82个钙化根管有72个根管扩通,达到根管预备要求,成功率87．80％。对照组76个钙化根管有17个根管扩通,成功率22．37％,两者之间有显著差异。结论：EDTA凝胶辅助机械预备钙化根管可提高根管疏通率。     

ProTaper手动镍钛锉临床应用体会

目的：评价用ProTaper手动镍钛锉对弯曲根管预备的临床效果。方法：随机将50个患牙158个根管分为两组，每组79个根管。实验组用ProTaper手动镍钛锉预备根管，对照组用不锈钢K型锉预备根管，记录每组操作时间和根管治疗术中反应情况。结果：实验组根管预备所用时间明显少于对照组（P〈0．05）；根管治疗术中反应实验组少于对照组（P〈0．05）。结论：ProTaper手动镍钛锉在弯曲根管预备方面有明显的优越性。     

三种方式预备磨牙重度弯曲根管的比较研究

目的研究3种方式预备磨牙重度弯曲根管的效果。方法牙髓炎、根尖周炎患者497个重度弯曲根管，根管弯曲度为25°～45°，按就诊顺序分为3组，A组167个根管应用G型钻联合手用不锈钢K锉采用逐步后退法预备根管，B组168个根管采用ProFile镍钛器械逐步深入法预备根管．C组162个根管采用不锈钢K锉逐步后退法预备根管。观察3组根管预备所需时间和形成台阶、器械折断、术后反应情况。结果A、B、C组根管预备平均时间分别为（173．55±32．38）s、（171．39±36．68）s和（230．42±45．76）S，A组与B组所用时间差异无统计学意义（t=1．08，P〉0．05），A组和C组（t=13．01，P〈0．01）、B组和C组（t=12．97，P〈0．01）所用时间经f检验差异有统计学意义，C组所厢时间多于A组、B组；3种方式预备磨牙重度弯曲根管，A组并发症发生率为20．96％，B组为24．40％，C组为41．98％，经卡方检验，差异有统计学意义（χ2=9．07，P〈0．05）。结论G型钻联合手用不锈钢K锉预备根管可节省预备时间，操作简单易行。     

两种K型锉预备弯曲人工根管效果的比较

目的 :比较镍钛K型锉和不锈钢K型锉常规法预备弯曲人工根管的切削能力和成形能力。方法 :分别用两种K型锉预备弯曲人工根管 ,电子分析天平称量标本的失重量 ,光学显微镜下观察根管形态变化。结果 :不锈钢K型锉切削能力较强 (P <0 .0 1) ,所有标本未发现根尖拉开、肘部形成和穿孔 ,预备后根尖孔直径镍钛K锉组明显小于不锈钢K锉组 (P <0 .0 0 1)。结论 :镍钛K型锉能保持弯曲根管良好的根管形态 ,而且试尖效果好 ,推荐临床使用     

5种手持根管器械预备弯曲人工根管的效果Ⅱ.成形能力比较

目的比较5种手持根管器械的成形能力。方法用光学显微镜观察5种手持根管器械常规法预备弯曲人工根管后的根管形态变化。结果所有标本未发现根尖拉开、肘部形成和穿孔。K－Flex组有75％的标本出现台阶，台阶的出现与根尖部树脂屑栓的形成有很密切的关系。K－Flex组和H挫组的根尖偏移较大，与K针组比较，有显著性差异（PMO．05），其余各组之；b］无显著性差异（P＞0．05）。结论通过综合评价5种手持根管器械预备弯曲人工根管的切削能力和成形能力，作者认为Unifile和K型挫是首选的器械。     

三种器械预备弯曲根管成形效果的比较

目的：评价K锉、Safesiders锉和HERO Shaper锉预备离体牙弯曲根管的成形效果。方法60颗根管弯曲的离体下颌前磨牙随机分为3组,分别用K锉、Safesiders锉和HERO Shaper锉进行根管预备,根管预备前后分别往根管内注入复方泛影葡胺并拍摄X线片,分析根管预备后根管弯曲内外侧壁牙本质去除量、中心定位能力及根管直化角度。结果在根管弯曲内外侧壁所有观测点,Safesiders锉组和HERO Shaper锉组牙本质去除量均少于K锉组（P均＞0.05）。 Safesiders锉组牙本质去除量多于HERO Shaper锉组,但仅在根管弯曲内侧壁3和4 mm观测点处差异有统计学意义（3 mm：t＝3.72,P＜0.05;4 mm：t＝7.62,P＜0.05）。在距根尖孔5 mm以下观测点,Safesiders锉组和HERO Shaper锉组中心定位能力优于K锉组（1 mm：F＝7.45,P＜0.05;2 mm：F＝10.20,P＜0.05;3 mm：F＝7.75,P＜0.05;4 mm：F＝23.45,P＜0.05;5 mm：F＝10.91,P＜0.05）;而在所有观测点上,Safesiders锉组与HERO Shaper锉组差异均无统计学意义（P均＞0.05）。 Safesiders锉组和HERO Shaper锉组根管直化角度均小于K锉组（F＝58.95,P＜0.05）,但Safesiders锉组与HERO Shaper锉组间差异无统计学意义（P＞0.05）。结论 K锉、Safesiders锉和HERO Shaper锉预备离体牙弯曲根管均有不同程度的根管偏移,其中Safesiders锉和HERO Shaper锉根管偏移较少,具有较好的根管成形效果。     

感染根管预备后根管内细菌种类和数量的变化

目的：研究根管预备对单根管牙根管内细菌数量和种类的影响。方法：选择21颗患慢性根尖周炎的单根管牙，用K锉行逐步后退法预备根管后再超声处理1min，分别于预备前，逐步后退法预备后，超声处理后根管内取样接种，然后检测根管内细菌数量和检出率的变化。结果：机械预备和超声处理后细菌数量明显降低，与预备前有显著性差异（P＜0．05），细菌检出率明显减少或清除根管内细菌。     

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。     

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.     

声波器械去除根管玷污层能力的比较研究

目的:比较声波、超声波和手用器械去除根管玷污层能力。方法:收集离体单根管的前磨牙40个,随机分为4组,分别由声波器械、超声波器械、手用器械以及声波和手用器械联合行根管预备,应用扫描电镜进行观察,采用Wilcoxon秩和检验进行统计学分析,根据根管表面的玷污层的量和牙本质碎屑比较声波器械去除根管玷污层的能力。结果:根尖1/3部分,在去除玷污层方面,声波器械组、超声波器械组以及声波器械和手用器械联合组,与手用器械组之间有显著性差异(P<0.05);在去除牙本质碎屑方面,超声波器械组与手用器械组之间亦有显著性差异(P<0.05),声波器械组以及声波器械和手用器械联合组与手用器械组之间有非常显著性差异(P<0.01)。声波器械组以及声波器械和手用器械联合组,与超声波器械组在去除玷污层和牙本质碎屑方面无显著性差异(P>0.05)。根中1/3和根上1/3部分,各组间比较均无显著性差异(P>0.05)。结论:根尖1/3根管预备,声波器械去除玷污层和牙本质碎屑的能力优于手用器械,尤其是去除牙本质碎屑的能力更强;与超声波器械近似。     

两种不同材料K锉预备弯曲根管时对根管壁应力的光弹应力分析

目的:分析和比较弯曲根管预备时,两种不同材料K锉与根管壁相互作用力的特点。方法:环氧树脂制作弯曲根管模型20个(弯曲半径5 mm,弯曲度30度)随机平分为2组,分别采用手用不锈钢K锉和手用镍钛K锉按逐步后退法进行根管预备。采用光弹应力分析法比较两种器械对根管壁作用力的大小及分布的差别。结果:#15,#20锉两组产生的平均应力面积(Average Amount of Stress,AAS)无显著差异;#25,#30,#35,#40组间比较,镍钛组在预备弯曲根管产生的AAS显著大于不锈钢锉组。SS组AAS在根管外侧壁明显多于根管内侧壁(P<0.05),NiTi组#25,#30,#35,#40产生的AAS根管外侧壁与内侧壁无显著差异(P<0.05)。结论:在使用#25,#30,#35,#40根管锉预备弯曲根管时,同号的NiTi K锉组对根管壁产生的应力小于SS K锉组。     

Debris retention and wear in three different nickel-titanium rotary instruments

The aim of this in vitro study was to compare three nickel-titanium (Ni-Ti) rotary instruments: EndoWave, K3 and ProFile, with respect to their debris retention and wear. Thirty simulated root canal models made from resin blocks with 40 degrees canal curvature were used. They were divided into three groups of 10 samples each; EndoWave, K3 and ProFile were used in Groups A, B and C respectively. They were prepared with four serial size files. The weight of each file was measured to evaluate debris retention and wear at four representative time points: prior to root canal preparation (W1), immediately after root canal preparation (W2), after ultrasonic cleaning (W3), after further additional cleaning (W4). The weight of debris on each file after root canal instrumentation and ultrasonic cleaning was calculated as D1: (W2 - W4) and D2: (W3 - W4) respectively. Also, wear of the file was calculated as WF: (W1 - W4). There was a significant difference in the amount of debris remaining on the file among the three files; EndoWave retained more debris (D1) than K3 and ProFile (P < 0.001, one-way anova). ProFile had the largest amount of debris (D2) remaining after ultrasonic cleaning (P < 0.001). Wear was not detectable in this study. Under the conditions of this study, immediately after root canal preparation, EndoWave retained the largest amount of debris, while ProFile retained the most debris even after ultrasonic cleaning.     

钙化根管的根管显微镜治疗

目的:探讨应用根管显微镜治疗钙化根管的方法,并对其疗效进行评价.方法:因根管钙化进行根管治疗的患牙33个,在根管显微镜引导下,将超声预备、手动NiTi器械预备以及EDTA化学预备相结合进行治疗,记录预备时间,术后1周进行根管充填,半年后复查并进行疗效评价.结果:根管显微镜下钙化根管的治疗成功率为88.9%,平均每根根管耗时25.8 min.结论:在根管显微镜引导下,将超声预备、手动NiTi器械预备以及EDTA化学预备相结合可提高钙化根管治疗的成功率.     

Evaluation of the smear layer removal effectiveness of EDTA using two techniques: an SEM study

Obtaining the cleanest canal possible before obturation is one of the goals of endodontic treatment. The purpose of this study was to compare the smear layer removal capability of ethylenediamine tetra-acetic acid (EDTA) application with passive ultrasonic and cotton wrapped on reamer activation. Twelve extracted human teeth with single root canals were used for the study. They were conventionally hand instrumented using reamers and K files. The apical aspect of the canals was enlarged to a #40 file. The teeth were divided into 4 four groups, instrumented and irrigated as follows: Group-A EDTA agitated at the end of preparation with cotton wrapped on a reamer for 1 min; Group-B EDTA applied with ultrasonic agitation for 1 min; Group-C irrigated with EDTA+sodium hypochlorite (NaOCl) (negative control group); and Group-D irrigated with distilled water (positive control group). After scanning electron microscopic study at three different levels, smear layer and dentinal tubules were scored. Means were tested for significance using the Z test. When the techniques were compared, the cotton wrapped on reamer agitation method was as successful as the ultrasonic activation of the files. Although all groups had significantly higher smear layer scores at apical compared to coronal sections, no significant differences were recorded.     

Efficiency of rotary nickel-titanium K3 instruments compared with stainless steel hand K-Flexofile. Part 2. Cleaning effectiveness and shaping ability in severely curved root canals of extracted teeth

AIM: To determine the cleaning effectiveness and the shaping ability of K3 nickel-titanium rotary instruments and stainless steel hand K-Flexofiles during the preparation of curved root canals in extracted human teeth. METHODOLOGY: A total of 60 root canals of mandibular and maxillary molars with curvatures ranging between 25 degrees and 35 degrees were divided into two groups of 30 canals. Based on radiographs taken prior to instrumentation with the initial instrument inserted into the canal, the groups were balanced with respect to the angle and the radius of canal curvature. Canals were prepared by K3 instruments using a crown-down preparation technique or by K-Flexofiles using a reaming motion up to size 35. After each instrument, the root canals were flushed with 5 mL of a 2.5% NaOCl solution and at the end of instrumentation with 5 mL of saline. Using pre- and post-instrumentation radiographs, straightening of the canal curvatures was determined with a computer image analysis program. After splitting the roots longitudinally, the amount of debris and smear layer were quantified on the basis of a numerical evaluation scale, using a scanning electron microscope. The data established for scoring the debris and the smear layer were separately recorded and analysed statistically using the Wilcox-on's test. RESULTS: None of the stainless steel K-Flexofiles but 5 K3 nickel-titanium instruments separated. Completely clean root canals were never observed. For debris removal, K-Flexofiles achieved significantly better results (P < 0.001) than K3 instruments. The results for remaining smear layer were similar (P > 0.05). K3 instruments maintained the original canal curvature significantly better (P < 0.0001) than K-Flexofiles. No significant differences were detected between the instruments (P > 0.05) for the time taken to prepare the canals. CONCLUSIONS: Under the conditions of this study, K-Flexofiles allowed significantly better removal of debris than K3 instruments. K3 files maintained the original curvature significantly better. A number of K3 instruments fractured.     

超声对Beagle犬前牙根管内微生物作用的实验研究

目的:研究超声根管治疗仪对根管内微生物的作用。方法:选择Beagle犬前牙建立根尖周炎模型,随机分成两组:一组为超声根管治疗组,另一组为常规根管预备组;常规组于预备前和预备至#25、#40时、超声组于超声冲洗10s、30s、60s后,分别于根管内取样接种,检测细菌数量和检出率的变化。结果:充分的机械预备、长时间超声根管冲洗后细菌数量明显降低,与预备前有显著性差异(P<0.05)。超声冲洗根管与单纯的器械预备对根管内细菌作用无显著差异。结论:超声处理能有效地减少根管内微生物数量,但其效果与单纯器械预备无明显差异。