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。     

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.     

连续波充填技术配合不同锥度牙胶尖充填根管的微渗漏研究

目的:通过体外检测从冠方向根尖方向渗漏的葡萄糖浓度,比较不同锥度牙胶尖配合连续波充填技术的充填质量.方法:选用单根管的离体前磨牙45个,随机分为3组,使用机用ProTaper镍钛器械预备至乃.A组使用0.04锥度牙胶尖配合连续波充填技术充填,B组使用ProTaper匹配锥度的牙胶尖配合连续波充填技术充填,C组使用0.02锥度牙胶尖用侧方加压技术充填.建立根管葡萄糖定量分析微渗漏模型,检测从冠方向根尖方向渗漏的葡萄糖浓度.结果:使用0.04锥度牙胶尖配合连续波充填技术组和使用ProTaer匹配锥度牙胶尖配合连续波充填技术组的葡萄糖渗出浓度无显著性差异,但均远低于侧方加压组.结论:连续波充填技术微渗漏小于侧方加压技术,不同锥度牙胶配合连续波充填技术的微渗漏无显著性差异.     

不同锥度牙胶尖根管充填的根尖封闭性研究

目的：体外评价不同锥度牙胶尖根管充填的根尖封闭能力。方法：将80颗单根管的上颌前牙经Protaper镍钛锉根管预备后,随机分为A、B、C 3个实验组(n=20)和阳性、阴性对照组(n=10), A、B、C组用0.02、0.04、0.06锥度牙胶尖冷侧压充填,对照组不做根管充填,通过染色法微渗漏实验和扫描电镜比较3组的根尖封闭能力。结果：阳性对照组根管全长均有染料渗入,阴性对照组根管内无染料渗入;A、B、C组染料渗入值分别为(3.262±0.304)mm、(3.236±0.292)mm、(2.300±0.368)mm,微缝隙分别为(14.43±14.77)μm、(14.13±14.46)μm、(4.97±4.51)μm;q检验结果显示：A、B组之间染料渗入和微缝隙无显著性差异(P＞0.05),C组与A、B组相比染料渗入和微缝隙有显著性差异(P＜0.05)。结论：选用与根管锥度一致的牙胶尖充填根尖封闭效果好。     

ProTaper简化预备法的根尖微渗漏实验研究

目的观察ProTaper简化预备法的根尖微渗漏,评价其根尖的封闭性能。方法 60颗离体成人患牙,分成2组。实验组30颗牙标本采用ProTaper机动系统简化预备和0.06锥度牙胶尖垂直加压充填根管,对照组30颗牙标本采用逐步后退法0.02锥度不锈钢锉预备和0.02锥度牙胶尖冷侧方加压充填根管,经透明标本染料渗透技术后,测量根尖部染料渗透的距离。结果实验组根尖染料的渗透距离均值0.60 mm,标准差0.29 mm,对照组根尖染料的渗透距离均值1.18 mm,标准差0.83 mm,2组根尖染料的渗透距离差异有统计学意义(P<0.05)。结论 ProTaper简化法预备根管配合相应锥度牙胶尖充填其根尖的封闭性能良好。     

不同锥度牙胶尖热垂直加压法根尖封闭性的研究

目的对不同锥度牙胶尖热垂直加压法根管充填的根尖封闭性进行比较。方法将62颗下颌切牙经GG钻及Hero642锉根管预备至0.06锥度30号,然后随机分为0.02锥度组（ 30颗）、0.06锥度组（ 30颗）和阳性对照组（ 2颗）,0.02锥度组和0.06锥度组分别应用0.02锥度牙胶尖和0.06锥度牙胶尖加Cortisomol糊剂热垂直加压法进行根管充填,阳性对照组不进行根管充填。将0.02锥度组和0.06锥度组中的10颗牙置入印度墨水中浸泡24 h,10颗牙置入印度墨水中浸泡10 d,10颗牙置入Hank′s平衡盐溶液67 d后再置入印度墨水中浸泡90 h。阳性对照牙置入印度墨水中浸泡24 h。应用立体显微镜三维测量根尖渗漏的线性长度,对根尖封闭性进行评价。结果阳性对照牙根管全长均有墨水染色。0.02锥度组随浸泡时间延长其根尖渗漏明显增加,0.06锥度组随浸泡时间延长根尖渗漏无明显增加。在浸泡24 h和10 d时,0.02锥度组和0.06锥度组的根尖渗漏距离无显著性差异（ P=0.601,P=0.471）;浸泡67 d时,0.02锥度组和0.06锥度组的根尖渗漏距离有显著性差异（ P=0.041）。结论使用与根管锥度相一致的牙胶尖进行根管充填,能够得到更好的根尖封闭性。     

EZ-FILL双螺旋器法根管充填的微渗漏测定

目的:测定EZ-FILL双螺旋器法和侧方加压根管充填的微渗漏差别.方法:选择50个离体单根管前牙和前磨牙,开髓后预备至0.08锥度,根尖孔预备至#35.样本随机分为4组.A组20例用Ez-FILL双螺旋技术进行根管充填.B组20例用根管侧方加压技术充填.C组5例为阳性对照组,D组5例为阴性对照组.用匍萄糖氧化酶比色测定法测定第1、2、4、7、10、15、20、25、30 d时根尖微渗漏的情况.结果:EZ-FILL根管充填组的微渗漏比侧方加压组稍低,但两组之间的差别无统计学意义(P>0.05).结论:Ez-FILL双螺旋器法充填根管操作简单迅速,同样可以达到侧方加压法相同的根尖封闭效果,有较好的应用前景.     

桩腔预备后剩余充填材料封闭根管能力的实验研究

目的:采用葡萄糖微渗漏模型检测桩腔预备后剩余充填材料封闭根尖的能力。方法:选取70颗单根管上颌前牙,随机分为4个实验组和2个对照组。采用逐步后退技术预备根管,AHp lus糊剂和牙胶尖侧向加压充填根管,然后G钻进行桩腔预备。实验组根管内剩余充填物长度分别为3、5、7、10 mm。用葡萄糖微渗漏模型检测第1、2、3和4周根管冠根向渗漏出的葡萄糖量。结果:实验第1周各组的葡萄糖微渗漏值无显著性差异(P>0.05),第2周起,第1组的微渗漏值高于第3、4组(P<0.05),而第1、2组之间无显著性差异(P>0.05)。结论:在保证桩核固位的前提下,应尽量多的保留根管内剩余充填物的长度。     

纳米根管充填材料根尖封闭能力的实验研究

目的 观察纳米材料根充后根尖微渗漏请况，评价其根尖封闭能力。方法 30颗离体单根管牙牙根，随机分为三组，每组10个，预备完成的根管用牙胶尖和一种根管糊荆、采用侧方加压法进行充填。根据染料在牙根中的渗入深度，评价根尖微渗漏情况。结果 三种材料的根尖微渗漏有显著差异（P〈0．01）；n-ZO组的根尖微渗漏最小，n-HA组次之，ZOE组最大。结论 纳米氧化锌糊剂和纳米羟磷灰石糊剂具有良好的根尖封闭性，可以作为根管封闭剞用于根管充填。     

不同锥度牙胶尖冷侧压充填根尖封闭性能的比较研究

目的：对比研究0.02锥度和0.06锥度牙胶尖冷侧压充填后根尖封闭效果.方法：收集离体单根管前牙53颗,经根管清理、机用ProTaper预备成型后随机分为2个实验组和1个阳性对照组,实验组每组26个样本,对照组1个样本.实验组分别用0.02锥度牙胶尖和0.06锥度牙胶尖作主尖冷侧方加压进行充填,阳性对照组不进行充填.用透明标本法配合染料渗透技术测量根尖染料的线性渗透长度,评价各组标本的根尖封闭效果.结果：阳性对照组标本染料全部进入根管.0.02锥度组染料渗透长度（0.761 ±0.457） mm,0.06锥度组（0.906±0.490） mm,差异无统计学意义（P＞0.05）.结论：机用ProTaper预备根管后,冷牙胶侧方加压充填时0.06锥度牙胶尖和0.02锥度牙胶尖的根尖封闭效果差异无统计学意义.     

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.     

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     

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.     

单尖法根管充填临床对比研究

目的比较单尖法、冷牙胶侧方加压法、Beefill 2 in 1热牙胶充填3种方法的临床效果。方法 180例牙髓病、根尖周病患者随机分为A、B、C 3组,分别采用冷牙胶侧方加压、Beefill2 in 1热牙胶充填、单尖法根管充填。观察患牙根充的时间、术后疼痛情况、恰充率、牙根纵折发生率及根充成功率。结果 C组根充的时间为(62.6±7.2)s,短于其他两组(P<0.01);C组术后疼痛率为1.67%,低于其他两组(P<0.05);C组的恰充率为98.33%,高于其他两组(P<0.05);C组牙根纵折发生率低;C组的根充成功率为96.61%与其它两组比较无统计学差异(P>0.05)。结论单尖法根管充填疗效高、操作时间短、牙折发生率低、值得临床推广应用。     

Stress distributions in internal resorption cavities restored with different materials at different root levels: A finite element analysis study

The aim of this study was to evaluate the stresses within simulated roots with internal resorption cavities at the apical, middle and coronal root levels, after obturation with gutta‐percha and/or MTA utilising finite element analysis (FEA). Mandibular premolar teeth with internal resorption cavities at different root levels were modelled. Models were restored with gutta‐percha and/or MTA. An oblique force of 300 N was applied and stress evaluations were carried out. In the MTA‐filled resorption models, the stresses were distributed more homogeneously than the gutta‐percha filled models, and the stress concentrations were lower in the remaining dentinal tissues. If the whole root is considered, the fully gutta‐percha‐filled models generated the highest stress values. Differences between the fully MTA‐filled models and hybrid techniques were present only in the apical resorption models. Both the MTA and combination of MTA and gutta‐percha can be suggested for use in clinical practice, in cases of internal root resorption cavity obturation.     

GuttaFlow常温流动牙胶充填下颌第二磨牙C形根管密合性的评价

目的评价GuttaFlow常温流动牙胶用于下颌第二磨牙C形根管充填密合性。方法收集63颗具有C形根管的下颌第二磨牙,Hero shaper镍钛根管预备后,随机分为3组,分别采用GuttaFlow常温流动牙胶、EQ plus热牙胶和冷侧压充填。然后距根尖2、4、6、8 mm处垂直于牙体长轴片切牙齿,体视显微镜下观察剖面,并采集图像,利用图像分析软件计算根管充填物中牙胶面积的百分比(PGP),评价充填牙胶和根管壁密合性。结果 GuttaFlow常温流动牙胶在距根尖2、4 mm处充填密合性优于热牙胶和冷侧压。在6、8 mm处GuttaFlow与热牙胶的充填密合性无明显可见差别,但均好于冷侧压组。结论 GuttaFlow常温流动牙胶在用于充填下颌第二磨牙C形根管时,具有良好的密合性。     

Ultramicroscopic study of the interface and sealing ability of four root canal obturation methods: Resilon versus gutta‐percha

Recently, filling materials have been introduced based on the dentine adhesion technologies used in conservative dentistry in an attempt to seal the root canal more effectively. The purpose of this study was to investigate the interface between the canal and root‐filling material. Sealing ability of four root canal obturation methods was analysed by means of scanning electron microscopy. Extracted single‐rooted teeth were endodontically treated and filled with gutta‐percha/Pulp Canal Sealer using the Thermafil (TH) technique, gutta‐percha/Pulp Canal Sealer using the System B (SB) technique, Resilon points/RealSeal (RS) and RealSeal 1/RealSeal (RS1). Specimen interfaces were analysed using field‐emission scanning electron microscopy. The adhesive groups RS and RS1, formed hybrid layers but showed areas of separation (gaps) similar to those in the conventional obturation groups. The RS and RS1 groups showed less separation in the coronal third, but the separation was similar to that in the TH and SB groups in the middle and apical thirds. The sealing ability of Resilon is not superior to that of existing materials.     

MicroSeal systems and modified technique

The MicroSeal technique was introduced in 1996 and consists of a nickel-titanium (NiTi) spreader, a NiTi condenser, a gutta percha heater, a gutta percha syringe, and a special formulation of gutta percha available in cones or in cartridges. It is considered a thermomechanical compaction technique that uses a rotary instrument to plasticize the gutta percha and move it within the root canal apically and laterally. The MicroSeal technique together with the author's modifications may be a very important tool in the hands of the endodontist. The MicroSeal system is able to preserve a conservative preparation and provide an adequate penetration by the obturation instruments in the apical third. Knowledge of the technique's indications and limitations represents an important step in the learning curve for those practitioners who are willing to incorporate a new obturation method into their clinical techniques.