根管偏移对充填材料封闭根管能力的影响

目的：研究弯曲根管预备后的根管偏移对充填材料封闭根管能力的影响。方法：选取73颗下颌单根管前磨牙作为研究对象，其中弯根管牙46颗，直根管牙27颗，A组23颗弯根管牙用Lightspeed器械预备根管，B组23颗弯根管牙，C组17颗直根管牙以及对照组牙用K锉预备根管，预备方法为逐步后退技术，使用双曝光X线技术和Ehrlich法测量根管偏移指数（AT1）的大小，使用侧向加压技术充填所有根管后，用流体传输模型测量每个根管内微渗漏的量，结果：A组中有19％的根管发生根管偏移，B组中有85％的根管发生根管偏移，两组之间AI1的大小有高度显著性差异，当ATI大于0．3nm，时，根管内微渗漏的发生率明显增加，结论：弯曲根管顶备中出现的根管偏移会削弱充填材料封闭根管的效果。     

即刻或延迟桩腔预备对充填材料封闭根管能力的影响

目的：通过流体传输模型测量根管微渗漏的大小，比较即刻桩腔预备和延迟桩腔预备对充填材料封闭根管尖部能力的影响。方法：90颗牙人下颌直根管前磨牙，逐步后退技术预备根管后，随机选择5颗牙为阴性对照组，5颗为阳性对照组。另80颗被随机分为A、B、C、D4组。所有根管均使用侧向加压技术充填，但A组、B组和阴性对照组的根管封闭剂为AH26，C组和D组的根管封闭剂为ulp Canal Sealer (PCS),阳性对照组不使用根管封闭剂。然后连接于流体传输模型，测定根管微渗漏的量。结果：A组与C组、B组D组之间的根管微渗漏的量没有显著性差异，而延迟桩腔预备组根管内微渗漏量显著大于即刻桩腔预备组。结论：延迟桩腔预备可以削弱充填材料封闭根管的能力。     

比较2种根管充填糊剂对根尖封闭性的作用

目的用染料渗透法测量根管微渗漏的程度,比较2种根管充填糊剂在根管充填后不同时间进行桩腔预备后对根尖部的封闭能力。方法选取90颗成人的上颌中切牙,逐步后退法预备根管,侧向加压技术充填根管,充填剂分别用Cortisomol糊剂（A组）和氧化锌丁香油糊剂（B组）,每组45颗上颌中切牙。根据根管充填后桩腔预备时间将A组上颌中切牙随机分为A1组、A2组和A3组,每组15颗,A1组为根管充填后即刻进行桩腔预备,A2组为根管充填后2周进行桩腔预备,A3组为根管充填后4周进行桩腔预备。根据根管充填后桩腔预备时问将B组上颌中切牙随机分为B1组、B2组和B3组,每组15颗,B1组为即刻进行桩腔预备,B2组为根管充填后2周进行桩腔预备,B3组为根管充填后4周进行桩腔预备。进行桩腔预备后用染料渗透法评价各组根尖渗透能力。结果Cortisomot组（A组）与氧化锌丁香油组（B组）在根管充填后相同时间进行桩腔预备后,根尖微渗漏的差异具有统计学意义（P〈0．01）。A组在根管充填后即刻、2周、4周时进行桩腔预备,其根尖微渗漏的差异具有统计学意义（P〈0．01）。B组在根管充填后即刻、2周、4周时进行桩腔预备,其根尖微渗漏的差异无统计学意义（P〉0．05）。结论Cortisomol根管充填糊剂的封闭作用效果比氧化锌丁香油糊剂好。     

弯曲根管不同预备方法对其根管充填密封性的影响

目的 研究临床常用预备方法预备弯曲根管对其根管充填密封性的影响.方法 选取不同弯曲程度的离体单根管牙齿90颗,分别使用不锈钢K锉,机用ProTaper,Hero642进行根管预备.AH-PLUS根充糊剂加牙胶尖冷侧压法充填,染料浸泡,分光光度法定量分析微渗漏.结果 不锈钢K锉组预备出的根管,充填后根尖孔微渗量最大,显著大于其余两种镍钛器械预备出的根管(P＜0.05).不同根管弯曲程度对根管充填后根尖孔产生微渗漏的影响程度不同,随着根管弯曲程度增加,发生根尖孔染料微渗量增加(P＜0.05);不锈钢K锉预备的Ⅲ°弯曲根管充填后出现的根管微渗量最大.结论 当使用冷侧压法充填根管,镍钛器械预备的根管相比不锈钢预备的根管更有利于根管充填后根尖孔的密封,尤其对于弯曲根管.     

3种根管扩大器械预备弯曲根管的体外实验

目的：运用手持根管扩大器械预备弯曲根管，观察根尖偏移发生率，方法：选取57颗弯曲单根管离体前磨牙作为研究对象，随机分成三组，A组19颗用Lightspeed镍钛合金器械预备根管，B组运用K锉，C组运用H锉，C组运用H锉，预备方法均为逐步后退技术，使用双曝光技术判断根尖偏移情况，结论：A组中有19％的根管发生了根尖偏移，B组中有82％发生了根尖偏,C且中有88％发生了根尖偏移，结论：运用Lightspeed镍钛器械预备弯根管可以减少根尖偏移的发生。     

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。     

不同根管预备方法对直根管即刻桩腔预备根尖封闭性影响的研究

目的观察直根管不同根管预备方法根管充填后即刻桩腔预备对根尖封闭性的影响。方法离体直单根管上前牙84个,其中80个按根管预备方法随机平均分为2组(n=40),A组:不锈钢根管锉常规法;B组:G型钻根管冠部预处理+不锈钢根管锉常规法,其余4个随机平均分配为阴性对照组和阳性对照组。所有根管均用侧方加压法充填,即刻垂直加压器去除部分充填材料,然后P型钻桩腔预备。用染料渗透法评价各组根尖封闭能力。结果B组的根管进行即刻桩腔预备后,其根尖微渗漏较A组轻(P<0.05)。结论大锥度根管预备,根管充填后即刻桩腔预备根尖封闭性较好。     

根管长度测量仪在根管预备中的应用

目的评价RootZX电子根管长度测量仪测量根管工作长度的准确性和实用性。方法选择门诊患者180颗牙共320个根管,随机分为2组。试验组90颗牙164个根管,用根管长度测量仪测量其工作长度,进行根管预备和充填,术后拍片;对照组90颗牙共156个根管,用X线牙片法确定根管的工作长度,进行根管预备和充填,术后拍片。结果RootZX组和X线组两组间比较根充结果差异有统计学意义(P<0.05)。结论ZootZX根管长度测量仪在根管预备中能准确、快速的测量出根管长度。     

即刻桩腔预备对三种根管预备方法预备的直根管根尖封闭性的影响

目的 研究三种不同根管预备方法根管预备、根管充填后即刺桩腔预备对直根管根尖封闭性的影响.方法 离体直单根管上前牙124个,其中120个随机平均分为3组(n=40),A组:不锈钢根管锉常规法;B组:G 型钻根管冠部预处理 不锈钢根管锉常规法;C组:手用Pr01raper镍钛根管锉冠向下法,刺余4个随机平均分为阴性对照组和阳性对照组.所有根管均用侧方加压法充填,即刻手持垂直加压器去除部分充填材料,然后P型钻桩腔预备.用染料渗透法评价各组根尖封闭能力.结果 B组G型钻根管冠部预处理 不锈钢根管锉常规法预备的根管和C组手用ProTaper镍钛根管锉冠向下法预备的根管即刻桩腔预备后,其根尖微渗漏较A组常规法预备的轻(P<0.05).结论 大锥度根管预备,根管充填后即刻桩腔预备的根尖封闭性较好.     

根管冠部预处理对前磨牙弯曲根管预备效果的影响

目的:研究根管冠部预处理对预备弯曲前磨牙根管时根尖偏移的影响。方法:将60个15°～35°的弯曲前磨牙根管按弯曲度排序后分成15个区组,每区组4个根管,再随机分配至4个不同处理组。其中2组根管冠部用GG钻预处理后,分别用不锈钢和镍钛合金K锉行常规法预备根管;另2个对照组直接行常规法根管预备;记录各组根管预备至不同锉号时的根管影像及器械尖端所在位置。最后,测量比较根管预备前后弯曲度的变化和不同锉根管预备后的根尖偏移指数(ATI)。采用t检验或配对资料的符号秩和检验进行统计学处理。结果:各组根管预备前后的弯曲度之间均有显著差异(P<0.01),ATI均随锉号的增大而增大。用不锈钢锉预备根管,经过冠部预处理,根管侧穿数目明显少于对照组,且30#锉所致的根尖偏移显著低于对照组(P<0.01),与同型镍钛合金K锉所产生的根尖偏移无差异(P>0.05)。结论:对于前磨牙弯曲根管,用镍钛合金锉预备,其效果优于不锈钢锉;不论是镍钛合金K锉还是不锈钢K锉,在用常规法预备弯曲前磨牙根管时,均应进行根管冠部预处理。     

Leakage along apical root fillings in curved root canals. Part I: effects of apical transportation on seal of root fillings

Occurrence of apical transportation (AT) may complicate the root filling procedure and result in a compromised seal. In part I of this study, human mandibular premolars with single, curved (21 to 39 degrees), or straight canals were prepared by Lightspeed or a step-back hand filing technique. An AT index was determined using a double exposure radiographic technique. The prepared canals were obturated using lateral condensation of gutta-percha. Leakage along the apical 3 mm of root filling was measured with a fluid transport model. After hand filing, AT and perforation occurred in 87% of the curved canals. The AT indices were > or = 0.4 mm. After Lightspeed preparation, AT occurred in only 19% of the curved canals. The hand filing/curved group leaked statistically significantly more than the hand filing/straight and Lightspeed/curved groups (p = 0.002). We conclude that occurrence of AT is a factor that negatively influences the apical seal when curved canals are obturated by lateral condensation of gutta-percha.     

Leakage along warm gutta-percha fillings in the apical canals of curved roots

Abstract – The aim of this study was to investigate the leakage along the apical portion of warm gutta‐percha obturated curved canals. Human mandibular premolars with single, curved (21°–40°) canals were prepared using the Lightspeed technique. Two groups of prepared canals, matched according to curvature and prevalence of apical transportation, were obturated by two techniques. Coronal gutta‐percha was removed immediately after root obturation was completed to simulate the procedure for post space preparation. Leakage along the apical 3 mm of root filling was measured with a fluid transport device. Vertical condensation of warm gutta‐percha and Pulp Canal Sealer provided less leakage than Thermafil plastic obturators and AH26 sealer (P=0.002).     

Evaluation of the Trifecta obturating technique

Abstract – The aim of this project was to evaluate and compare the radiographic quality and sealability of root fillings in extracted human teeth using lateral condensation of gutta‐percha or the Trifecta obturating system. One hundred freshly extracted human mature, single‐rooted teeth were divided into four identical groups of 25 teeth on the basis of root canal shape. The root canals of two groups were prepared in such a way as to produce a relatively parallel canal shape with little or no flare towards the coronal orifice. The root canals of the other two groups were prepared in such a way as to produce a canal shape that was deliberately more flared to ensure that they were wider at the orifice than at the endpoint of the preparation. All root canals were flushed with 17% EDTA solution and 2.5% NaOCl to remove the dentinal smear layer. The canals of one flared and one parallel group were obturated using cold lateral condensation and the canals of the other two groups were obturated using the Trifecta system. The sealability of each technique was assessed by a dye penetration method. The radiographic quality of obturation was determined for each canal using a 4‐point scale. Canals filled with thermoplasticised gutta‐percha had significantly less apical dye penetration than those obturated by lateral condensation (P<0.001). Lateral condensation achieved significantly better scores for radiographic quality than thermoplasticised gutta‐percha from both the bucco‐lingual (P<0.001) and the mesio‐distal views (P<0.001). Root canals obturated using the Trifecta technique showed significantly more apical extrusion of sealer than those obturated by lateral condensation (P<0.001). Under laboratory conditions the Trifecta technique had better sealability but poorer radiographic quality than lateral condensation.     

后牙弯曲根管充填方法的根尖封闭能力研究

本实验用常规法、逐步后退法和超声法三种方法预备后牙弯曲细小根管，再分别用传统侧压充填法和热侧压充填法进行充填，然后比较其根尖封闭能力。结果表明：热侧压充填法的根尖封闭能力优于传统的侧压充填法，并能在一定程度上弥补常规法和超声法预备弯曲细小根管成形不佳的缺陷，增加其根尖封闭能力     

不同根管充填技术对椭圆形根管的根尖封闭效果

目的 探讨采用不同根管充填技术对椭圆形根管根尖封闭效果的影响.方法 选取近期拔除的椭圆形单根管前磨牙120颗随机分成6组,每组20颗,采用iRoot-SP和AH-Plus根管封闭剂,结合单尖充填法、连续波热牙胶垂直加压充填法、冷牙胶侧方加压充填法,即单尖iRoot组、热牙胶iRoot组、冷牙胶iRoot组、单尖AH组、热牙胶AH组、冷牙胶AH组,采用染料渗透法观察根尖的微渗漏情况.结果 热牙胶iRoot组、热牙胶AH组的根尖染料渗入深度明显小于单尖iRoot组、单尖AH组(P<0.05);热牙胶iRoot组、冷牙胶iRoot组尖染料渗入深度明显小于热牙胶AH组、冷牙胶AH组(P<0.05);其他的组间两两比较差异均无统计学意义(P>0.05).结论 热牙胶垂直加压技术可以使椭圆形根管达到更好的根尖封闭效果,且配合使用iRoot SP根管封闭剂的封闭效果较配合使用AH-Plus根管封闭剂好.     

机用镍钛Hero642预备磨牙弯曲根管的临床研究

目的探讨机用镍钛器械Hero642应用于磨牙弯曲根管预备的效果。方法选择根管弯曲的磨牙86颗,先采用小号K锉疏通根管,将根尖部预备至15号后,再以机用镍钛器械Hero642完成根管预备,侧向加压充填根管,根据治疗前后的x线片评价根管预备和充填效果。结果86颗磨牙共有274个根管,264个根管形态良好,无台阶、根尖堵塞、根管偏移及侧壁穿孔等并发症发生。根充恰填256个,8个根管超充,10个根管未能完全扩通,无法到达根尖孔而欠充或做塑化治疗。结论手用锉疏通弯曲根管的根尖段后再以机用镍钛器械Hero642完成根管预备,可获得良好的成形效果且较少产生并发症。     

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     

Limit of root canal obturation by gutta percha compaction technique in single rooted teeth. Clinical data apropos of 168 canals]

After the introduction of the lateral compactage of gutta percha in endodontic clinic of OdontoStomatology Institute of Dakar in 1995; the immediate evaluation of the quality and the limit of the canal obturation due to a prospective study on 157 monoradicular teeth so be 168 canals (11 supplementary canals) has shown that 75% of canals are of type I of Vertucci and that the apical limit of security is reached within 80.25% of cases. The manual step back canal preparation (79.17%) and the technique of canal obturation by lateral compactage of gutta percha [(64.88%); Apical limit of security: 59.52%] permit to obtain a densities (95.83%) and homogeneous (79.57%) canal obturation. The indication of gutta percha compactage on monoradicular teeth (hermetic and tridimensional root canal filling) must avail to apical curved roots of lateral incisive, the use of adapted instruments in case of canines (31 mm) and apical stop cone on necrotic pulp teeth.