根管冲洗液及血液对根尖定位仪测量准确性的影响

目的研究4种常用根管冲洗液及血液对根尖定位仪测量准确性的影响。方法收集40颗根尖孔发育完成的单根管离体牙构建体外实验模型。测量根管工作长度实际值;应用Raypex-5根尖定位仪分别测量在根管内灌注4种冲洗液（生理盐水、体积分数3%过氧化氢溶液、质量分数5.25%次氯酸钠溶液、体积分数17%乙二胺四乙酸溶液）和血液介质环境下的根管工作长度测量值。对测量数据进行单因素方差分析。结果 40个根管的工作长度实际值和在生理盐水、体积分数3%过氧化氢溶液、质量分数5.25%次氯酸钠溶液、体积分数17%乙二胺四乙酸溶液及血液5种介质中根尖定位仪根管工作长度测量值分别为（17.61±2.25）mm、（18.18±1.33）mm、（17.89±1.30）mm、（17.77±1.56）mm、（16.58±1.38）mm和（16.44±1.61）mm,差异无统计学意义（F=1.963,P=0.091）。结论 Raypex-5测量根管工作长度的准确性不受根管内残留冲洗液和血液的影响。     

3种根尖定位仪不同条件下定位根管侧穿孔准确性的体外研究

目的 比较Propex、Raypex(R)5、Root ZX根尖定位仪在不同根管冲洗液中定位根管侧穿孔位置的准确性.方法 选取19颗新鲜拔除的前磨牙,采用ET40超声工作尖破坏根管中下部根管壁,制备根管侧穿孔.使用Propex、Raypex(R)5、Root ZX根尖定位仪定位穿孔位置,比较3种根尖定位仪在不同根管冲洗...     

声波与超声波器械配合不同冲洗液对根管清理效果的扫描电镜研究

目的：比较声波与超声波根管器械配合不同冲洗液预备根管的清理效果。方法：制作根管扫描电镜标本，观察根管玷污层分布和牙本质小管暴露情况，各标本的冠1／3、中1／3、根尖1／3区域各取10个500倍视野照相，分级评分(玷污层分数，SL)。统计学分析比较三种冲洗液条件下声波和超声波器械根管清理的差异。结果：仅以蒸馏水作冲洗液，声波不能有效清理碎屑与玷污层；25g／L NaClO冲洗，根尖1／3玷污层的去除超声组优于声波组，但未清除玷污层栓层；25g／L NaClO结合170g／L EDTA作冲洗液，玷污层去除显著且两组无显著差异，但根尖1／3差于根管中上段，超声组部分区域牙本质小管蚀刻与融合。结论：声波结合25g／L NaClO和170g／L EDTA可有效去除玷污层并达到与超声器械近似的根管清理效果，根管内荡洗去除玷污层栓层效果显著，且未对根管壁产生破坏，但有必要加强根尖部荡洗。     

被动超声冲洗对弯曲根管的碎屑清理能力和根管形态的影响

目的: 评价被动超声冲洗在弯曲根管内碎屑清理能力和根管偏移量。方法: 选取下颌磨牙近中弯曲根管36个,弯曲度在25°以上,以机用 XP-endo Shaper根管锉预备根管。根据弯曲长度（curved length,CL）和冲洗方式分为A1组（CL>3 mm,注射器冲洗）、B1组（CL>3 mm,超声K锉冲洗）、C1组（CL>3 mm,irrisafe超声锉冲洗）、A2组（CL<3 mm,注射器冲洗）、B2组（CL<3 mm,超声K锉冲洗）和C2组（CL<3 mm,irrisafe超声锉冲洗）,每组6个样本。对所有样本冲洗前、后进行Micro-CT扫描,计算冲洗后根管内体积增加量和根管偏移量。采用SPSS 22.0软件包对数据进行统计学分析。结果: 在CL>3 mm的根管根尖区,PUI+irrisafe组的根管体积增量显著高于PUI+K锉和注射器冲洗（P<0.05）,并且在距离根尖孔5 mm处PUI+irrisafe形成的根管偏移量显著低于PUI+K锉（P<0.05）;与注射器冲洗相比无显著差异（P>0.05）。在CL<3 mm的根管中,PUI+irrisafe组和PUI+K锉组的根管体积增量均显著高于注射器冲洗（P<0.05）,但根管偏移量与注射器冲洗无显著差异（P<0.05）。结论: 在弯曲长度较大的根管中,被动超声冲洗结合预弯锉可获得更好的清理效果;而在弯曲长度较小的根管中,被动超声冲洗结合K锉和预弯锉均安全有效。     

以强化戊二醛根管消毒冲洗剂的临床观察

我科自 1997年开始用强化戊二醛替代 FC和氯亚明作根管的消毒冲洗用药 ,并和它们做了对比观察 ,现报道如下 :1临床资料和方法1.1　一般资料切牙、尖牙、前磨牙的急慢性根尖周围炎 12 2例 ,其中急性根尖周围炎 97例 ,慢性根尖周围炎 2 5例 ,男性 6 6例 ,女性 5 6例 ,年龄 18～ 6 6岁 ,切牙 5 0例占 40 . 98% ,尖牙 12例占9.83% ,前磨牙 6 0例占 49.18%。1.2　病例选择临床确诊的各型急性根尖周围炎 ,慢性根尖周围炎 ;慢性根尖周围炎伴有初次形成窦道者。1.3　药物市售 FC液 ;体积分数为 2 %强化戊二醛碱性水溶液 (A溶液 ) ;体积分数为 2 0 …     

超声清理髓室对感染根管预备后根尖周反应的影响

目的 研究感染根管预备中使用超声清理髓室对根尖周反应的影响.方法 210颗牙髓坏死或慢性根尖周炎的磨牙按就诊顺序随机分为2组,每组105颗.试验组在根管预备过程中除用3%过氧化氢液和生理盐水冲洗液冲洗外,再加用超声洁牙机清理髓室;对照组仅用3%过氧化氢液和生理盐水冲洗液冲洗.观察根管预备1周内的术后反应.结果 试验组术后根尖周反应发生率为17.14%,对照组术后根尖周反应发生率为46.67%, 2组术后反应的发生率差异有统计学意义(P＜0.05).试验组术后反应相对较轻,试验组术后有3颗患牙发生中度根尖周急性反应,无重度根尖周反应;对照组术后有14颗发生中度根尖周急性反应, 5颗发生重度根尖周急性反应.结论 感染根管预备过程中,超声清理髓室可减轻术后根尖周反应.     

不同超声冲洗液和不同时间对根管预备后清洁效果的扫描电镜观察

目的　比较不同超声冲洗液及不同超声冲洗时间对根管预备后清洁的效果。方法　80颗离体单根管上颌前牙应用机用镍钛Protaper根管预备至F3后随机分为8组,分别用不同冲洗液超声冲洗1 min和3 min,A、B组用复方氯己定含漱液,C、D组用3%H2O2溶液,E、F组用蒸馏水,G、H组用17%EDTA溶液。最后将牙体沿颊舌向纵劈,扫描电镜观察各组样本在根颈、中、尖1/3牙本质碎屑与玷污层的清除情况,根据评分统计分析比较各组根管清洁效果。结果　不同冲洗液超声冲洗1 min时,在根颈部和根中部,G组与其它各组之间比较有显著性差异（P＜0.05）。在根尖部,G组与C组差异有统计学意义（P＜0.05）,C组与A、E组比较差异有统计学意义（P＜0.05）。不同冲洗液超声冲洗3 min时,在根颈部和根中部,H组与其它各组之间比较有显著性差异（P＜0.05）。在根尖部,H组与D组比较无显著性差异（P＞0.05）,但与B、F组比较差异有统计学意义（P＜0.05）。相同冲洗液不同冲洗时间时, A、B组在根中及根尖部差异有统计学意义（P＜0.05）,C、D组在根尖部差异有统计学意义（P＜0.05）,E、F组之间和G、H组之间比较无显著性差异（P＞0.05）。结论　17%EDTA溶液超声冲洗1 min就可去除根管玷污层和碎屑。3%H2O2和复方氯己定含漱液超声冲洗1 min效果虽不及17%EDTA,但适当延长冲洗时间可增强根尖部清洁效果。     

ProPex根尖定位仪在C形根管系统准确性的研究

目的 对ProPex根尖定位仪测量C形根管工作长度的准确性进行评价。方法 对24颗即将拔除的、术前X线片显示牙根部呈锥形或方形融合、开髓后证实为C型根管的下颌第二磨牙局麻下开髓、拔髓、冲洗,用ProPex根尖定位仪测量78个根管的工作长度(WL);完整拔除牙齿后测量根管的实际长度(AL),比较WL与AL的长度差异。结果 以距根尖孔以内0.5mm为误差标准,ProPex根尖定位仪准确率为85.90%;以距根尖孔以内1.0mm为标准,准确率为91.03%;以距根尖孔以内1.5mm为标准,准确率为94.87%。结论 Propex根尖定位仪在C形根管工作长度确定方面的准确性较高,具有简便、快速、准确、安全、避免多次X线照射等优点,能大大缩短临床椅旁时间,提高根管治疗的效率。     

不同根管冲洗针头对S形弯曲根管冲洗效果的影响

目的:比较临床常用的2种冲洗针头对S形弯曲根管冲洗效果的影响。方法:采用80个树脂模拟弯曲S形根管,随机分成两组：IrriFlex组(A组)和NaviTip FX组(B组),分别预备至25^#0.06锥度和30^#0.04锥度各40个。根据根管冲洗针头、冲洗位置和预备形态分为A1组(IrriFlex,最大冲洗深度,25^#0.06锥度)、B1组(NaviTip FX,最大冲洗深度,25^#0.06锥度)、A2组(IrriFlex,最大冲洗深度,30^#0.04锥度)、B2组(NaviTip FX,最大冲洗深度,30^#0.04锥度)、A3组(IrriFlex,距根尖孔4 mm, 25^#0.06锥度)、B3组(NaviTip FX,距根尖孔4 mm, 25^#0.06锥度)、A4组(IrriFlex,距根尖孔4 mm, 30^#0.04锥度)、B4组(NaviTip FX,距根尖孔4 mm, 30^#...     

体内不同冲洗液对ROOT ZX电测仪准确性的影响

目的:体内评价不同冲洗液对Root ZX根尖电测仪测量结果的影响.方法:150颗需根管治疗的单根管牙随机分为5组,开髓,冠向敞开后同时去除根管内牙髓后分别以3 %H2O2、17?TA、0.5%NaOCl、生理盐水冲洗根管3次,最后一次保留冲洗液,进行根管测量.空白组为0.5%次氯酸钠和生理盐水交替冲洗后的干燥根管.各组测量3次的平均值与X片确定的根管长度值以单因素方差分析(ANOVA)分析各组间差异.结果:各组根管长度测量值与实际根管长度无显著性差异,单因素方差分析显示各组间测量值无显著性差异.结论:ROOT ZX根尖定位仪能准确测量根管长度,且不受根管内冲洗液的影响.     

Dynamic recording of irrigating fluid distribution in root canals using thermal image analysis

AIM: To investigate the influence of the size and the depth of insertion of irrigating needles, and the diameter of the master apical file on flow distribution during fluid irrigation in root canals. METHODOLOGY: Stepback canal instrumentation was employed on seven extracted human single canal teeth. The size of the master apical files ranged from sizes 25, 30, 35, 40, 45, 50 to size 80 within the seven teeth, respectively. A thermal imaging system (ThermaCAM; National Instruments Co., Austin, TX, USA) was used to record the dynamic fluid distribution following root canal preparation. The dynamic fluid distribution was analysed during irrigation by insertion of different irrigating needle tips (23, 25 and 27 gauge) at various depths (3, 6 and 9 mm) from the root apex. The whole process of irrigation was recorded by a video camera and analysed by two observers separately. The success of the irrigation process was defined when the irrigant was able to flow into to the apical region immediately after injection. RESULTS: The aqueous irrigant was flushed into the apical region when a size 27 gauge irrigating needle was placed into a size 30 canal at a point 3 mm from the apical stop. When the same needle tip was placed 6 mm from the root canal apex, successful irrigation was achieved only in the canals prepared to size 50 or larger. When a size 25 gauge irrigating needle was placed 3 mm from the working length, the canal size had to be no <45 to allow for successful irrigation. When a size 23 gauge needle was placed at the same position, the canal needed to be prepared to size 50 to allow thorough irrigation of the apex. At 9 mm from the apical stop, none of the irrigating needles could achieve successful irrigation of any canal size. CONCLUSION: The flow distribution of root canal irrigation can be affected adversely by large diameter irrigating needles, by greater distances between the needle tip and the apical stop, and by narrow root canals.     

Ex vivo evaluation of the ability of four different electronic apex locators to determine the working length in teeth with various foramen diameters

BACKGROUND: The aim of this ex vivo study was to evaluate the accuracy of four electronic apex locators (EALs) to determine the working length in teeth with various foramen diameters. Our previous study revealed that electronically measured canal length was influenced by the root canal diameter. It is not known whether foramen size would interfere with the reading accuracy of an EAL. METHODS: A total of 36 extracted human lower single rooted premolar teeth were divided into four groups of nine teeth each. In groups A, B and C, the root canals were instrumented using #10-80, #10-100 and #10-120 K-files, and the tip of size #80, #100 and #120 K-files were permitted to pass through the apical foramen to a length of 1mm, respectively. In group D, the teeth were instrumented using #10-140 K-files and the tip of #140 K-file was permitted to pass through the apical foramen to a length of 5 mm. Thus, the average apical foramen diameters in groups A, B, C and D were approximately 0.82 mm, 1.02 mm, 1.22mm and 1.5 mm, respectively. The teeth were then mounted in 1% agar and four EALs were used: Root ZX, Foramatron D10, Apex NRG and Apit 7. For electronic measurement, sizes #10 and #80, #10 and #100, #10 and #120, and #10 and #140 K-files were used for groups A, B, C and D, respectively. During electronic measurement the canals were flushed with 6% sodium hypochlorite solution. RESULTS: Three-way ANOVA and Bonferroni test showed that EAL, file size and foramen size all had a significant influence on the measurement error (P<0.0001), with all the interactions between these three factors being significant (P<0.0001). CONCLUSIONS: The four EALs were unreliable to determine the working length of teeth with a wide apical foramen, when using a small size file. The Root ZX and Foramatron D10 showed significantly better scores than the other two EALs and may be more reliable to determine the working length of teeth with a wide apical foramen, if a tight-fit file is used.     

超声冲洗对感染根管内毒素的灭活及清除作用

目的探讨超声冲洗对感染根管内毒素的灭活及清除作用。方法选择因严重慢性根尖周炎拔除的具有双根管的离体上颌前磨牙10颗,常规开髓,用改良双敞法预备根管,将3％过氧化氢溶液30 μL注入根管,行超声振荡,每根管振荡2 min,分别于根管预备后和超声振荡后取样,测量内毒素活性。另外在临床患者中选择患有慢性根尖周炎的双根管上颌前磨牙10颗,采用相同的方法进行根管预备,预备后以无菌蒸馏水为介质进行超声冲洗,每根管均冲洗2 min,分别于根管预备前、根管预备后和超声冲洗2 min后根管取样,测量内毒素活性。内毒素活性的测定采用动态浊度法鲎试验,并对超声处理前后根管内毒素活性的差异进行分析。结果离体牙超声振荡前,根管内毒素的活性平均为4.069 EU·mL-1,超声振荡后为16.410 EU·mL-1,二者差异有统计学意义（P<0.01）,超声振荡后内毒素活性明显升高。临床样本中,根管预备前、根管预备后和超声冲洗后根管内毒素的平均活性分别为44.860、4.099、0.116 EU·mL-1,根管预备前与根管预备后内毒素活性的差异有统计学意义（P<0.01）,根管预备后内毒素活性明显下降;根管预备后与超声冲洗后内毒素活性的差异也有统计学意义（P<0.01）,超声冲洗后内毒素活性明显下降。结论在模拟临床操作的条件下,采用口腔科超声根管治疗仪进行超声冲洗可以明显增强根管冲洗液清除感染根管内毒素的作用,但不能增强根管冲洗液灭活感染根管内毒素的作用。     

In Vitro Evaluation of a Novel Root Canal Endoscope for Visualizing the Apex of Curved Root Canal Models and an Extracted Tooth

Introduction

In straight root canals, intraradicular structures around the root canal orifice and apical foramen can be visualized with a dental operating microscope and commercially available root canal endoscopes. However, the root apex area, including the apical foramen, in a curved root canal cannot be visualized using these devices. In the present study, the potential of a newly developed root canal endoscope implementing an image fiber was examined in 3 types of root canal models and extracted teeth.

超声波冲洗根管对充填质量的影响

目的 探讨超声波冲洗根管对根管充填质量的影响.方法 选择离体单根牙44颗,20颗为超声波组,根管预备中用超声波冲洗根管;20颗为注射器组,根管预备中用注射器冲洗根管;2颗为阳性对照组,2颗为阴性对照组.通过X线检查和根尖微渗漏实验比较根管充填质量.结果 超声波根管冲洗组和手用注射器根管冲洗组,X线检查评价两组根管充填质量差异无统计学意义(P＞0.05).超声波组根尖微渗漏值低于注射器组(P＜0.05).结论 超声波冲洗根管有利于提高根尖封闭性.     

Comparison of the flow characteristics of irrigants with standard and Max‐i‐Probe needles

The objectives of this study were to determine the direction and pattern of flow of irrigating solutions inside simulated root canals with different irrigation needles; and to determine whether different needle designs increase the likelihood of irrigating solution passing through the apical foramen. Two types of needles were compared: a standard needle with a bevel and an open end, and a needle with a side opening and closed rounded tip. Observations of irrigant flow within the canals indicated that the side‐venting needle can be dangerous if the needle gauge is small and it reaches the full length of the canal, since this allowed irrigants to flow into the periapical area. With the standard needle, the fluid did not go beyond the tip of the needle when minimal irrigating pressure was employed. As the size of canal increased, the fluid did not extrude beyond the tip of both needles. However, if the needles bound in the canals, then the fluid was forced away from the needle tip, and the pressure applied to the syringe was directly proportional to the distance the fluid flowed away from the needle tip. Both side‐venting and standard needles can be used for irrigation safely and effectively if a dynamic irrigation technique (moving the needle up and down inside the canals while irrigating) is employed.     

Distance from file tip to the major apical foramen in relation to the numeric meter reading on the display of three different electronic apex locators

Aim  To establish and compare the relationship between the distance from the file tip to the apical foramen and the numeric meter reading on the display of three different electronic apex locators (EALs).
Methodology  A total of 12 extracted intact, straight, single-rooted human teeth with complete roots were used. The actual root canal length (AL) was determined after access preparation. For the electronic measurements with each EAL, silicon stops were fixed with auto-polymerizing resin to size 15 K-files at AL and 0.5, 1, 2, 3, 4 mm short of AL. The data was analysed by two-way anova and Tukey's honestly significant difference (HSD) test for multiple comparisons amongst EALs. Additionally, one-way anova and Tukey's HSD test were carried out for multiple comparisons amongst the measurements of each EAL.
Results  There was a statistically significant difference amongst all EALs in indicating the position of file tips in relation to the major foramen ( P  < 0.05). The correlation between the meter reading and the position of the file tip from the apical foramen was statistically significant in the three EALs. There were significant differences amongst the measurements at distances from 0 to 2 mm in Justy III. In Dentaport, significant differences were found from 0 to 1 mm. However, the E-Magic Finder showed significant differences from 0 to 0.5 mm.
Conclusions  Justy III was more capable of displaying the intracanal position of the file tip from the major foramen in mm whilst advancing through the root canal during electronic measurements than the Dentaport and E-Magic Finder Deluxe.     

A comparison between two electronic apex locators: an ex vivo investigation

AIM: To compare ex vivo the performance of the Apex Finder and the Root ZX apex locators, with and without irrigant, in canals having different diameters. METHODOLOGY: Sixty canals in 60 teeth were prepared using stainless steel hand files and 0.04 taper NiTi rotary instruments. During preparation the narrowest diameter of the canal was transported to the apical root surface. The canals were irrigated with RC-Prep and 5% NaOCl solution. Six groups were obtained, each with 10 canals having the same diameter of foramen, either 0.15, 0.20, 0.25, 0.40, 0.60 and 0.80 mm. A size 15 K-file was advanced into each canal until its tip was observed under x10 magnification to reach the foramen and the corresponding length recorded. The measurements were performed to an accuracy of 0.25 mm as a base unit of length. The teeth were then fixed to a plastic bar suspended over a glass container filled with 0.9% NaCl solution. Each apex locator was tested when the K-file was at the foramen, or 0.5, 1.0, 1.5 and 2.0 mm short; with the root apex immersed into the solution; with the canal dry or irrigated with NaCl. To evaluate the accuracy of both electronic apex locators (EALs) each electronically determined distance was compared with the actual length and the data analysed using the General Linear Model and the Student t-test. RESULTS: Out of 2400 measurements 100 were electrically unstable, all with the Root ZX. In total, 521 measurements located the position of the file tip beyond the apex, in general, in high conductive conditions with the Root ZX and in low conductive conditions with the Apex Finder. No significant difference in terms of accuracy was found between the two EALs when the file tip was at the foramen (Root ZX mean +0.12 mm, SD 1.22 mm; Apex Finder mean +0.57 mm, SD 1.16 mm). Comparing all the measurements performed with the file tip within 2 mm of the foramen, in all the different conditions tested, the accuracy was affected (P<0.025) by diameter of the foramen, type of EAL, distance to the apex, and by several interactions. CONCLUSIONS: Under the different ex vivo conditions both EALs provided accurate measurements when the file tip was at the foramen. The accuracy of the Apex Finder was negatively influenced by high conductive conditions, whilst the Root ZX provided inaccurate and unstable measurements mostly in low conductive conditions.     

Irrigant flow within a prepared root canal using various flow rates: a Computational Fluid Dynamics study

Aim  To study using computer simulation the effect of irrigant flow rate on the flow pattern within a prepared root canal, during final irrigation with a syringe and needle.
Methodology  Geometrical characteristics of a side-vented endodontic needle and clinically realistic flow rate values were obtained from previous and preliminary studies. A Computational Fluid Dynamics (CFD) model was created using FLUENT 6.2 software. Calculations were carried out for five selected flow rates (0.02–0.79 mL sec⁻¹) and velocity and turbulence quantities along the domain were evaluated.
Results  Irrigant replacement was limited to 1–1.5 mm apical to the needle tip for all flow rates tested. Low-Reynolds number turbulent flow was detected near the needle outlet. Irrigant flow rate affected significantly the flow pattern within the root canal.
Conclusions  Irrigation needles should be placed to within 1 mm from working length to ensure fluid exchange. Turbulent flow of irrigant leads to more efficient irrigant replacement. CFD represents a powerful tool for the study of irrigation.