超声波预备根管与Nd：YAG激光照射后根管牙本质的SEM研究

目的：评价超声预备根管及Ｎｄ：ＹＡＧ 激光照射根管壁后,根管内壁的清洁度和管壁牙本质微结构的变化。方法：１２ 个离体成人上前牙分为４ 组制备根管：手用器械、超声根管治疗仪、手用器械＋ Ｎｄ：ＹＡＧ 激光照射、超声波＋ Ｎｄ：ＹＡＧ 激光照射,扫描电镜下观察并照像记录。结果：手用扩锉预备的根管内壁有涂层污染和病理组织残留;超声波预备后根管内壁清洁、涂层消除,牙本质小管口开放;手用器械或超声制备后辅以适当能量激光照射的管内壁牙本质小管口封闭,管间牙本质熔融,并形成空泡状结晶。结论：超声波预备根管可达到理想的清洁效果,但牙本质小管口开放易造成根管术后渗漏。而Ｎｄ：ＹＡＧ 激光照射有利于封闭牙本质小管口,减少根尖孔渗漏,还具有封闭根管内壁死腔的作用。     

不同方法预备根管对根管治疗后牙齿冠渗漏的影响

目的采用3种不同方法预备根管,评价其对根管治疗后牙齿冠渗漏的影响。方法48颗单根管离体牙随机分为4组,使用不同的根管预备方法去除根管壁的玷污层。A组为对照组,采用生理盐水和过氧化氢溶液冲洗根管;B组采用乙二胺四乙酸（EDTA）凝胶和5.25%次氯酸钠溶液冲洗;C组采用Odontoson-M型超声波治疗仪荡洗;D组采用脉冲Nd: YAG激光照射。每组取2颗牙,于扫描电子显微镜（SEM）下观察冠部玷污层的去除情况;其余10颗牙采用Obtura Ⅱ高温注射式热牙胶垂直加压法充填根管,氧化锌丁香油黏固剂封闭根管口,浸于质量浓度20 g·L-1亚甲基蓝溶液中染色7 d,脱水脱钙制作透明牙标本,体视显微镜下测量染料渗入的深度。结果SEM观察：A组
整个根管内壁被覆玷污层及大量碎屑,牙本质小管被堵塞;B组与C组根管内壁清洁,玷污层消失,牙本质小管开放;D组根管内壁牙本质小管封闭或半封闭,玷污层熔融消失。A、B、C、D组染料渗入深度分别为（2.15±0.38）、（1.75±0.28）、（2.04±0.40）、（1.73±0.36）mm。A组的渗入深度明显高于B、D组,其差异有统计学意义（P<0.05）。结论使用不同的方法预备根管去除玷污层,可以减少根管治疗后牙齿的冠渗漏。     

桩道预备后剩余根管充填物的根尖封闭作用评价

目的:比较不同根管充填方法及桩道预备后不同长度的充填材料对根尖的封闭作用,寻找根管充填方法和剩余充填材料的最佳搭配选择,为临床应用提供理论依据.方法:132颗单根管牙随机分为6个实验组(每组各20颗)和2个对照组(每组各6颗).根管预备后A、B、C3组行冷牙胶侧方加压充填,桩道预备后分别剩余4、6、8 mm根管充填物;D、E、F3组行连续波热牙胶充填,桩道预备后分别剩余4、6、8 mm根管充填物;G组(阴性对照组)随机选择不同充填方法及不同长度剩余根管充填物:H组不进行根管充填.利用葡萄糖定量检测微渗漏模型,检测各组从冠方向根方渗漏的葡萄糖浓度(体积).采用SPSS 19.0软件包对数据进行统计学分析.结果:A和D、B和E、C和F比较,冷牙胶侧方加压充填组微渗漏显著大于热牙胶充填组.A和B、A和C、D和E、D和F相比,差异均具有显著性;B和C、E和F相比,无显著差异,说明根尖剩余4 mm和6 mm组间具有显著差异,而剩余6 mm和8 mm组间无显著差异.结论:连续波热牙胶充填技术的根尖封闭性能显著优于冷牙胶侧方加压法.桩道预备后剩余6 mm微渗漏较少.是较合适的剩余充填材料长度.     

Obtura Ⅱ热塑牙胶改良充填法的实验研究

目的探讨将常温流动牙胶充填术融入高温注射式热牙胶充填技术的可行性。方法 70颗单根管离体牙根管预备后随机分组,分别采用ObturaⅡ充填(A组)、Touch-heat+ObturaⅡ充填(B组)、GuttaFlow+ObturaⅡ充填(C组)、冷牙胶侧压充填(D组)、不做充填(E组),根充完成后修整所用充填根管内牙胶长度为10 mm,建立葡萄糖微渗漏模型,通过对葡萄糖定量分析检测根管充填后根尖部微渗漏,观察比较根尖封闭效果。结果各组葡萄糖微渗漏随观察时间延长持续增加,3组实验组微渗漏差异无统计学意义(P>0.05)。结论 GuttaFlow+ObturaⅡ充填法封闭效果可靠且操作易行,有一定的可行性。     

不同根管预备方法和充填技术组合对根尖微渗漏和牙根抗折强度的影响

目的探讨几种根管预备方法和充填技术组合对根尖微渗漏和牙根抗折强度的影响。方法选取离体牙186颗,随机分为6个实验组(A、B、C、D、E、F,每组各30颗牙)和阳性、阴性对照组(G、H,每组3颗牙)。A、B、C组采用逐步深入法进行根管预备,D、E、F组采用逐步后退法。其后,A、D组使用Bee FillTM2in1热牙胶充填系统进行根管充填,B、E组给予Cortisomol糊剂配合热牙胶以垂直加压法,C、F组予以Cortisomol糊剂配合冷牙胶以侧方加压法,G、H组均不做任何充填。采用染料渗透法检测各组离体牙根尖微渗漏情况,对各组离体牙进行纵向抗折强度力学测试。结果相同充填方法下多个预备方法比较,A、B、C组染料渗透长度分别小于D、E、F组(P<0.05),A、B、C组最大抗压负荷分别大于D、E、F组(P<0.05)。相同预备方法下,A组染料渗透长度小于B、C组(P<0.05),D组染料渗透长度小于E、F组(P<0.05);A、B、C组最大抗压负荷依次降低(P<0.05),D、E、F组最大抗压负荷依次降低(P<0.05)。G、H组间最大抗压负荷比较,差异无统计学意义(P>0.05)。结论使用逐步深入法进行根管预备,并联合Bee FillTM2in1热牙胶充填系统应用于根管治疗能够显著减少根尖微渗漏,并提高牙根抗折强度,对根管预备和充填技术的选择具有一定的借鉴意义。     

E-Q根管充填系统的实验研究

目的 :体外评价E -Q根管充填系统的充填质量和封闭根尖能力。方法 :离体单根管恒牙 5 5个 ,随机分为 3组 ,每组 17个 ;通过X线与根尖微渗漏实验 ,比较E -Q根管充填系统 (包括A组 :固核载体插入技术 ,B组 :热牙胶旋转推入技术 )和冷牙胶侧方加压充填技术 (C组 )的充填质量和封闭根尖能力。结果 :糊剂超充以A组最多 ,B组次之 ,C组最少 (P <0 .0 5 ) ;近中远中向根充质量以C组最好 (P <0 .0 5 ) ,颊舌向各组差别无统计学意义 ;封闭根尖能力以A组最强 ,B组次之 ,C组最差 (P <0 .0 5 )。结论 :E -Q根管充填系统有较好的封闭根尖能力 ,但X线充填质量差于侧方加压技术     

半导体激光照射根管内壁的扫描电镜研究

目的：应用波长1320nm的半导体激光照射根管内壁,观察其扫描电镜图像改变,方法：取6颗新鲜离体上颌中切牙,随机分成A,B,C三组,A组常规根管预备加单模光纤连接波半导体激光照射5分钟;B组常规根管预备加连续波激光照射两次,每次5分钟,间隙30分钟;C组为常规根管参备对照组,三组牙齿标均进行扫描电镜观察,结果：A组部分管间牙本质熔融,呈均质状结构,玷污层大部分消失,管壁散在附着少量白色结晶样物质,牙本质小管大部分封闭,B组牙本质小管全部封闭,管壁平坦,管间牙本质熔融,呈均质状结构,玷污层消失,管壁干净无碎屑,C组根管内壁覆盖了大块不规则玷污层,可见少许牙本质小管,而且所有标本根管壁未见裂隙和碎裂现象。结论,激光照射根管内壁,可使管壁表面玷污层消除,产生熔融层,有利于根管治疗。     

连续波热牙胶充填技术根尖封闭性能的评估

目的体外实验比较不同器械预备根管后连续波热牙胶根管充填技术的根尖封闭能力。方法离体双根管上颌前磨牙随机分为机用ProFile预备组和不锈钢K锉预备组,分别采用连续波热牙胶充填技术和冷侧压法进行根管充填,用染料渗透法和透明标本法测量根尖微渗漏,评价各组根尖封闭能力。结果各组根尖微渗漏距离无统计学差异(P>0.05)。结论连续波热牙胶充填技术与冷牙胶侧方加压充填技术的根尖封闭能力无显著性差异;对直根管和轻度弯曲的根管,不同器械根管预备后其根管充填效果无明显影响。     

根管截面形态对超声根尖倒预备效果的影响

目的 研究不同根管截面形态(椭网形和圆形)对超声根尖倒预备效果的影响.方法 选取直的单根管离体牙,根据根管截面形态分为椭圆形根管组和网形根管组,每组各20颗,分别进行根管预备和充填,截去根尖3 mm.采用超声工作尖进行根尖倒预备,在体式显微镜和扫描电镜下观测根尖窝洞形态规则性、残余牙胶量和窝洞清洁程度.结果 体式显微镜观测结果显示两组根尖窝洞形态规则性差异有统计学意义(P<0.01),椭圆形组中所有样本均可见牙胶残余,圆形组中70%的样本无牙胶残余,超声倒预备后残余牙胶量椭圆形根管组高于圆形根管组(P<0.01);电镜观测结果显示,圆形组85%的样本存在玷污层,95%的样本可见开放牙本质小管;椭圆形组中所有样本均有玷污层存在,仅40%的样本可见开放牙本质小管,根尖窝洞清洁程度椭圆形根管组低于圆形根管组(P<0.01).结论 超声根尖倒预备难以完全去除玷污层,椭圆形根管倒预备效果比圆形根管差.     

桩腔预备对冷热牙胶充填根管根尖封闭性的影响

目的:通过葡萄糖定量检测法检测根管桩腔预备后微渗漏的大小,比较连续波热牙胶充填和冷牙胶侧压充填后桩腔预备对根尖封闭性的影响。方法:50颗单根管牙,采用冠向下法,使用ProTaper机用镍钛系统预备根管。随机选择5颗牙为阴性对照组,5颗牙为阳性对照组。另40颗牙随机分为A、B、C、D 4组,每组10颗,A组、B组、阴性、阳性对照组使用连续波热牙胶充填术充填根管,阳性对照组不使用根管封闭剂,C组、D组使用冷牙胶侧压充填术充填根管,然后A组:即刻、B组:第7天、C组:即刻、D组:第7天进行桩腔预备。采用葡萄糖定量法测定第2、7、14、21、28天从冠方向根方渗漏的葡萄糖量。结果:第14天起A、B 2组之间,C、D 2组之间,A、C 2组之间,B、D 2组之间,葡萄糖渗漏量差异均有显著性(P<0.05)。结论:延迟桩腔预备会削弱充填材料和封闭剂封闭根管的能力,连续波热牙胶充填的根尖封闭能力优于冷牙胶侧压充填。     

Influence of smear layer on depth of penetration of three endodontic sealers: an SEM study

Abstract— The purpose of this study was to examine the effect of the smear layer on the penetration depth of Sealapex, Roth 811, and CRCS root canal sealers into the dentinal tubules. Forty recently extracted, human single-rooted teeth were used. The crowns were cut and removed at the cemento-enamel junction level and the root canals were prepared to a #60 K-file. The teeth were then randomly divided into two groups of 20, group A and group B. The smear layer was removed from all teeth in group A with EDTA and NaOCl. The smear layer remained in all teeth in group B. Two roots in each group were used as controls. Six roots from each group were obturated with Roth 811 sealer and gutta-percha through lateral condensation. The same process was repeated using sealers CRCS and Sealapex. Each root was then divided in two and prepared for scanning electron microscope observation. The removal of the smear layer allowed penetration of all three sealers into the dentinal tubules to a depth of between 35 μm and 80 μm. Although the CRCS sealer penetrated only up to the 35 mm point, it offered better or complete obturation of the dentinal tubules. The presence of smear layer at the root canal walls obstructed the penetration of all sealers into the dentinal tubules.     

The effect of root canal preparation on microleakage within endodontically treated teeth: an in vitro study

AIM: The purpose of this study was to evaluate the effects of smear layer and canal instrumentation on leakage in root-filled teeth. METHODOLOGY: Six groups (n = 12) of freshly extracted human canines and premolars with closed apices and single roots were used. Groups A, B, C, and D were instrumented with engine-driven rotary nickel-titanium MCXIM files and Groups E and F were instrumented with conventional stainless steel hand files. Groups A, C, and E were flushed with 3.0 mL of 17.0% REDTA to remove the smear layer prior to obturation. All teeth were flushed with 5.25% NaOCl, then obturated with AH-26 sealer and either the lateral condensation (Groups C-E) or thermomechanical compaction technique (Groups A and B). Copper wire was placed coronally in contact with the gutta-percha in each tooth and, after immersion in 0.9% NaCl solution, a 10 volt dc voltage was connected between each tooth and a stainless steel electrode. The current flow in the circuit was observed for 45 days. One way ANOVA and Duncan's Multiple Range Test were used to compare Groups A-F at time intervals of 10, 20, 30 and 45 days and identify statistically significant differences. RESULTS: Significantly less microleakage occurred when the smear layer was removed and when the canals were obturated with thermoplasticized gutta-percha. Canals instrumented with engine-driven NiTi files exhibited less leakage than hand-instrumented canals irrespective of obturation method. CONCLUSIONS: Smear layer removal is beneficial to root canal sealing. Obturation with thermoplasticized gutta-percha provides a superior seal whilst canal instrumentation with engine-driven NiTi files reduces the extent of microleakage in root canals.     

单尖法和热牙胶法根管充填根尖封闭性能的比较研究

目的 比较3种封闭剂AH-Plus, iRoot SP和GuttaFlow2分别配合单尖法充填和热牙胶充填的根尖封闭性能。方法 选取近期拔除的70颗单根管前磨牙,截冠后采用Waveone gold系统预备至P#,随机分为6个实验组(每组10颗)和2个对照组(每组5颗)。分别行单尖法充填和热牙胶充填,即AH-Plus单尖法组(A1组),AH-Plus热牙胶组(A2组),iRoot SP单尖法组(B1组),iRoot SP热牙胶组(B2组),GuttaFlow2单尖法组(C1组),GuttaFlow2热牙胶组(C2组),阳性对照组(D组)和阴性对照组(E组)。将充填完成的牙齿进行染料渗透实验后,通过纵切片法检测根尖的微渗漏情况。结果 A1组微渗漏值最大,B2组微渗漏值最小,同种封闭剂下单尖法充填和热牙胶充填根尖封闭性差异无统计学意义(P>0.05),同种充填技术下3种封闭剂的封闭性差异无统计学意义(P>0.05)。结论 3种根管封闭剂均不能完全封闭根管,单尖法充填和热牙胶充填在根尖封闭效果上无显著差异。     

The influence of the smear layer on dentinal tubule penetration depth by three different root canal sealers: an in vitro study

The effect of the smear layer on the penetration depth of three different root canal sealers into the dentinal tubules was examined in 64 recently extracted single-rooted teeth. After chemomechanical preparation, the samples were randomly divided in two equal groups. The smear layer remained intact in group A, whereas complete removal of the smear layer was performed in group B. Two roots from each group were used as controls. Ten roots from each group were obturated with laterally condensed gutta-percha points and sealers AH Plus, Apexit, and Roth 811, respectively. Examination in scanning electron microscope revealed that the smear layer obstructed all the sealers from penetrating dentinal tubules. In contrast, smear layer removal allowed the penetration of all sealers to occur to a varying depth. These findings suggest that smear layer plays an important role in sealer penetration into the dentinal tubules, as well as in the potential clinical implications.     

3种根充糊剂微渗漏的实验研究

目的评价3种根充糊剂的根管封闭性能。方法收集新鲜拔除的人前牙100颗,随机分为A、B、C 3个实验组（每组30颗牙齿）和D、E 2个对照组（每组5颗牙齿）,A、B、C组分别采用Vitapex糊剂、AH- plus糊剂、氧化锌丁香油（ZOE）糊剂加牙胶尖侧压充填根管,D组为阳性对照组,E组为阴性对照组。牙齿用2%甲基兰溶液浸泡,脱矿使牙齿透明,在根管显微镜下测量染料渗入根管的长度。结果A、B、C组染料渗入长度分别为（0.57±0.56）mm、（0.79±0.96）mm、（1.07±1.12）mm,阳性对照组染料渗入根管全长,阴性对照组无染料渗入。A组与B、C组间染料渗入长度有显著性差异（P<0.01）,B组与C组间染料渗入长度无显著性差异（P>0.05）。结论Vitapex糊剂根尖封闭性优于AH- plus糊剂与ZOE糊剂。     

玷污层及封闭剂对Ultrafil-3D系统根尖封闭的影响

目的:观察有无玷污层及不同类型的封闭剂对Ultrafil-3D系统根管充填封闭性的影响。方法:64颗人离体单、直根管前牙预备后,将其中的60颗分为有玷污层与无玷污层组,各组分别采用3种封闭剂(AH-plus、Roekoseal、CRCS)并以Ultrafil-3D牙胶(Firmset)充填根管,其余4颗作为对照。所有标本在2%亚甲蓝中浸染5d,将牙体近远中向纵劈后,测量染料的线性染色长度。采用SAS6.04软件包进行方差分析及t检验。结果:(1)无论玷污层去除与否,CRCS组的微漏均显著大于AH-plus及Roekoseal组(P<0.05);(2)去除玷污层前后,使用3种封闭剂的染料微漏均无显著差异(P>0.05)。结论:AH-plus及Roekoseal与Ultrafil-3D牙胶联合使用,能增加根管充填的密合性,去除玷污层不能明显减少微漏的发生。     

5种根管充填糊剂的根管封闭能力的比较

目的：比较5种根管充填糊剂的根管封闭能力。方法：选择75个直根管的恒牙,经开髓拔髓,Mtwo镍钛根管器械预备后反复冲洗后随机分为5组,分别采用实验组1：氧化锌丁香油糊剂,实验组2：Endomethasone根管充填糊剂,实验组3：Cortisomol根管充填糊剂,实验组4：Vitapex糊剂,实验组5：AH-plus糊剂,加牙胶尖严密充填。将所有离体牙置于37℃,100%湿度的恒温箱3d后选用透明牙染色法测量微渗漏深度。结果：实验组1：（2.35±0.768）mm,实验组2：（1.78±0.548）mm,实验组3：（1.54±0.322）mm,实验组4：（3.22±0.452）mm,实验组5：（0.98±0.536）mm。各组微渗漏深度值差异有显著性（P〈0.05）。其中实验组4的微渗漏值显著高于其他各组（P〈0.05）,实验组5的微渗漏值显著低于其他各组（P〈0.05）,实验组2的微渗漏值稍高于实验组3,结果无显著差异。结论：在Mtwo镍钛器械预备下,AH-Plus糊剂充填根管可有效的减少根管微渗漏的发生,但长远疗效有待进一步的观察。     

An immunohistological study of the localization of bacteria invading root pulpal walls of teeth with periapical lesions

We immunohistologically examined the prevalence and localization of bacteria invading dentinal tubules of the roots of teeth with infected canals. Forty extracted teeth with apical lesions were selected and divided into two groups: a group of untreated teeth and a group of canal-enlarged teeth. The bacteria in the specimens were detected by Brown-Brenn stain and the labeled-streptavidin-biotin method with specific antisera for 16-bacteria. Seventy percent of the examined teeth showed bacteria invading the dentinal tubules of the roots. Fusobacterium nucleatum, Eubacterium alactolyticum, E. nodatum, Lactobacillus casei, and Peptostreptococcus micros were abundant. Even in the canal-enlarged group, invasion of bacteria was observed in 65% of teeth. This study revealed the actual condition of bacteria in infected root dentin and suggested that the canal-enlargement procedure could not completely remove all the bacteria in the infected dentinal tubules of the root.     

Nd:YAG激光照射根管后的形态学观察

目的：了解感染根管管壁牙本质的病变特点，根管预备及Nd：YAG激光照射对感染根管的作用。方法：选用单根患牙60颗，随机分为5组：对照组（治疗前感染根管）、根管预备组（用手用器械根管预备）、3个激光组（在常规根管预备后，采用3种不同能量参数照射1min），做扫描电镜观察。结果：对照组：感染根管牙本质小管形态不规则，排列紊乱。根管预备组：能去除病变的牙本质层，形成玷污层。50mj 10Hz激光组不能封闭牙本质小管。100mj 10Hz、150mj 10Hz激光照射1min根管壁呈熔融状态，去除了玷污层，牙本质小管封闭和半封闭。结论：激光剂量在100mj 10Hz或在此以上时，能有效清洁根管壁玷污层和封闭牙本质小管。