三种超声仪根管冲洗效果的比较

目的:比较Odontoson-M,P-MAX和Spartan3种超声仪根管冲洗的效果。方法:选择完整离体单直根管前磨牙,采用不锈钢K锉和逐步深入技术根管预备后超声冲洗。冲洗后纵向劈开标本,采用数码照相机照相和扫描电镜观察,分别计算比较根管内碎屑百分数及牙本质小管开口数。结果:以5g/L次氯酸钠为冲洗液时,Odontoson-M超声仪在根管中1/3区的碎屑百分数明显低于其他2种超声仪(P<0.05),管壁牙本质小管的开口数明显多于其他2种超声仪(P<0.05)。结论:在实验条件下,Odontoson-M超声仪根管冲洗效果可能好于其他2种超声仪。     

不同浓度次氯酸钠根管超声冲洗的实验研究

目的：比较不同浓度次氯酸钠溶液的根管冲洗效果。方法：选择根尖发育完成的单、直根管前磨牙50颗,随机分为5组,每组10颗。不锈钢K锉和逐步深入技术根管预备后,分别使用蒸馏水,0．5％、1％、2％或5．25％次氯酸钠进行根管超声冲洗。采用数码照相机照相和扫描电镜观察,分别比较根尖1／3区和根中1／3区根管内的碎屑百分数和牙本质小管开口数。结果：蒸馏水组在根尖和根中1／3区的碎屑百分数明显高于其他4组,牙本质小管开口数明显少于其他4组;去除蒸馏水组后,0．5％次氯酸钠组在根中1／3区的碎屑百分数明显高于其他3组,牙本质小管开口数明显少于其他3组。结论：4种不同浓度次氯酸钠溶液的根管冲洗效果均好于蒸馏水;0．5％次氯酸钠根管冲洗的效果比其他3种较高浓度的次氯酸钠差。     

不同冲洗液对根尖溢出碎屑的影响

目的： 比较根管预备后不同冲洗液对根尖溢出碎屑的影响。方法：58颗正畸拔除的单根牙随机分为4组,常规根管预备后,采用不同冲洗液冲洗,对照组(A组)：7颗、蒸馏水冲洗;实验组每组17颗,B组：1% NaOCl冲洗;C组：2.5% NaOCl冲洗;D组：17% EDTA冲洗。收集冲洗后的冲洗液,通过紫外可见分光光度计检测吸光度（OD）值,比较其根尖溢出碎屑的含量。采用SPSS 13.0软件包对结果进行统计学分析。结果：冲洗前、后的OD差值分别为对照组A组0.012、B组0.122、C组0.393、D组0.021,B、C、D 3组冲洗前、后的差值与对照组相比,均有显著差异（P<0.05）。其中,C组最高,与B、D 2组相比,均差异显著（P<0.05）。结论：冲洗液能增加根尖溢出碎屑的含量,2.5%NaClO冲洗液产生较多的根尖溢出碎屑,1% NaOCl、17%EDTA溶液是临床上较理想的冲洗液。     

不同冲洗剂对桩道内壁牙本质形态的影响

目的:比较3种冲洗液5.25%NaClO溶液和15%EDTA溶液、0.2%的氯己定溶液对桩道内壁形态的影响。方法:筛选18颗新鲜拔出单根管前磨牙,在釉牙骨质界上2 mm处截冠,随机分成3组。常规根管充填、桩道预备后分别用A:蒸馏水(对照组)、B:5.25%NaClO溶液和15%EDTA溶液、C:0.2%的氯己定溶液冲洗桩道,将牙根纵向劈开。选取能够较好展示根管壁的一侧作为样本,扫描电子显微镜观察根中1/3的牙本质表面,按Gorman分类法记分,记录数据并统计分析。结果:A组玷污层较厚,有中等量杂质及碎屑残留,牙本质小管极少或不可见;B组清洁程度最高,玷污层极少,极少量杂质及碎屑残留,牙本质小管开口较清晰;C组有部分玷污层,少量杂质及碎屑残留,牙本质小管开口部分可见。各组差异有统计学意义(P<0.05)。结论:冲洗处理对桩道对牙本质表面有影响,应用5.25%NaClO溶液和15%EDTA溶液冲洗效果最好。     

根管超声冲洗效果的扫描电镜研究

目的用扫描电镜的方法评价根管超声冲洗的效果。方法选择直单根管前磨牙20颗，随机分为超声冲洗组（U组）和注射器冲洗组（S组）。用逐步后退法预备根管后，2组选用不同方法，均用40ml2．5g／L NaOCI最后冲洗根管。样本去冠后沿牙长轴纵向劈开，扫描电镜观察，记录电镜照片上牙本小管开口的数目并对均数进行统计学分析。结果U组牙本质小管开口数明显多于S组（P〈0．05）；2组相应部位比较，颈1／3处牙本质小管开口数之间的差异无统计学意义（P〉0．05），U组在根中1／3和根尖1／3的牙本质小管开口数数明显多于S组（P〈0．05）。结论用2．5g／L NaOCl超声根管冲洗效果优于用注射器冲洗。     

穿心莲纳米乳液用于根管冲洗的清洁性实验研究

目的:评价穿心莲纳米乳液用于根管冲洗的清洁性。方法:收集50个新鲜拔除的单根管前磨牙,随机分为5组。采用镍钛锉冠向下法预备根管,分别使用5组冲洗液进行根管冲洗。A组为穿心莲纳米乳液,B组为穿心莲提取液,C组为1%次氯酸钠(NaClO),D组为3%NaClO,E组为0.9%的生理盐水。最后每组分别用17%乙二胺四乙酸二钠(EDTA)、生理盐水冲洗根管。采用数码相机和扫描电镜观察,分别比较根尖、根中和根冠1/3区根管内碎屑百分数和玷污层评分。结果:根尖1/3:E组碎屑百分数和玷污层明显高于其他4组,C组玷污层评分明显高于A组和D组(P<0.05)。根中1/3:E组碎屑百分数和玷污层评分明显高于其他4组,C组碎屑含量明显多于A组和D组(P<0.05)。根冠1/3:E组碎屑百分数和玷污层评分明显高于其他4组,C组玷污层评分明显高于D组(P<0.05)。结论:冲洗液的清洁性排序：3%NaClO、穿心莲纳米乳液、穿心莲提取液、1%NaClO、生理盐水。穿心莲纳米乳液被认为是可能用于根管冲洗的中药冲洗液。     

复方冰硼冲洗液体外抑菌效果的评价

目的 评价纯中药制剂复方冰硼冲洗液和冰硼冲洗液对4种牙髓病原菌的体外抗菌活性。方法 采用琼脂稀释法,测定复方冰硼冲洗液和冰硼冲洗液对4种厌氧病原菌牙龈卟啉单胞菌、中间普氏菌、具核梭杆菌和粪肠球菌的最小抑菌浓度（MIC）和最小杀菌浓度（MBC）。结果 2种冲洗液对4种厌氧病原菌均有抗菌作用,复方冰硼冲洗液的抗菌性优于冰硼冲洗液。粪肠球菌的抗药能力明显强于其余3种菌株。结论 纯中药制剂复方冰硼冲洗液具有良好的抗菌性,作为根管冲洗液可能是有优势的。     

XP-endo Finisher锉对根管内壁玷污层清除效果的体外研究

目的 评估XP-endo Finisher（XPF）锉与被动超声冲洗（PUI）对根管内壁玷污层的清除效果。方法 选择60颗离体单直根管下颌前磨牙,距根尖16 mm处截冠,采用S3镍钛锉预备到3S,根据终末处理方式不同将样本随机分成6组。A组：3 mL 3%次氯酸钠溶液联合XPF处理1 min;B组：3 mL 3%次氯酸钠溶液联合XPF处理1 min,再用4 mL 17%乙二胺四乙酸（EDTA）溶液冲洗1 min;C组：3 mL 3%次氯酸钠溶液联合PUI处理1 min;D组：3 mL 3%次氯酸钠溶液联合PUI处理1 min,再用4 mL 17%EDTA溶液冲洗1 min;E组：3 mL 3%次氯酸钠溶液30号侧方冲洗针冲洗1 min;F组：3 mL 3%次氯酸钠溶液30号侧方冲洗针冲洗1 min,再用4 mL 17%EDTA溶液冲洗1 min。采用扫描电子显微镜观察玷污层形态,并比较根尖1/3区、根中1/3区牙本质小管开口数。结果 A、C、E组实验样本整个根管壁都有玷污层覆盖,A组与C组牙本质小管开口数明显高于E组（P<0.05）,而A组与C组的差异无统计学意义（P>0.05）;F组根中区、B组和D组根尖区有少量玷污层覆盖,牙本质小管开放或半开放;F组根尖区可见玷污层,牙本质小管封闭或半封闭;B和D组根中区根管壁玷污层均被有效去除;在根尖1/3区和根中1/3区,B组与D组牙本质小管开口数高于其他4组（P<0.05）,而B组和D组间的差异无统计学意义（P>0.05）。结论 XPF锉对根管内壁玷污层的清洁效果与PUI无明显差异,可用于根管预备后提高根管清洁效果。     

5种冲洗剂组合对前牙直根管清洁效果的比较

目的：比较5种冲洗剂组合对前牙直根管的清洁效果。方法：25颗离体直根管前牙,随机分为5组,不锈钢K锉常规法预备根管．应用5种冲洗剂组合进行冲洗。第1组：根管器械预备期间和预备结束后依次用1％NaOCl和3％H2O2冲洗;第2组：根管器械预备期间用1％NaOCl冲洗,预备结束后用17％EDTA冲洗;第3组：根管器械预备期间和预备结束后依次用1％NaOCl和17％EDTA冲洗：第4组：根管器械预备期间依次用17％EDTA和1％NaOCl冲洗,器械预备结束后用17％EDTA冲洗;第5组：根管器械预备期间依次用17％EDTA、1％Triton X-100(表面活性剂)和1％NaOCl冲洗．器械预备结束后用17％EDTA冲洗。每组冲洗剂剂量和冲洗时间均为22ml和7min。将牙纵劈后进行扫描电镜观察。结果：第1组,根管壁上见典型玷污层结构和大量杂质和残屑。第2组在根管冠、中1／3能部分去除玷污层．根尖1／3残留大量玷污层。第3组虽然能有效去除玷污层．但会引起牙本质小管中度腐蚀。第5组在根管冠、中1／3能部分去除玷污层,但根管壁上黏着大量杂质和残屑．此外还存在重度腐蚀现象。第4组根管清洁效果最好,且对牙本质小管无腐蚀性。结论：在严格控制冲洗时间和顺序的情况下,联合应用17％EDTA和1％NaOCl能有效去除玷污层．且不会腐蚀牙本质小管。     

不同冲洗液及冲洗时间对牙本质微硬度的影响

目的:比较不同冲洗液对牙本质微硬度影响。方法:收集新鲜拔取上颌前牙60个,并沿在釉牙本质界截去牙冠,进行根管预备。再将处理好的牙根沿牙体长轴纵向切开分为两部分。再将得到的120个样本分为5组,分别用5.25%NaOCl、2.5%NaOCl、2%洗必泰、3%H2O2和生理盐水处理5min、10min或15min。然后用微硬度测定仪检测根管牙本质的微硬度。结果:5.25%NaOCl、2.5%NaOCl和3%H2O2冲洗都降低了牙本质微硬度。同样冲洗时间里,5.25%NaOCl组牙本质微硬度较2.5%NaOCl都低,且牙本质微硬度随冲洗时间增加降低。2%洗必泰对牙本质微硬度没有产生影响。结论:采用2%洗必泰冲洗或控制次氯酸钠溶液的浓度和冲洗时间可减少冲洗液对牙本质微硬度的影响。     

Efficacy of final irrigation--a scanning electron microscopic evaluation

The purpose of this in vitro study was to determine the degree of removal of pulpal remnants and smear layer from root canals after final irrigation with three different solutions. During instrumentation the step-back preparation and 1% NaOCl were used. The final 4-min, 30-ml irrigation varied as follows: group I, 10 ml of 1% NaOCl + 10 ml of 10% citric acid + 10 ml of distilled water; group II, 15 ml of 0.5% NaOCl + 15 ml of EDTA-T; and group III, 10 ml of 5% NaOCl + 10 ml of 3% H2O2 + 10 ml of 5% NaOCl. Scanning electron microscopic photomicrographs were evaluated for the mean number of visible open dentinal tubules by three observers. The largest number of visible tubules in the three groups was in the cervical third, followed by the middle and apical thirds. There was no statistically significant difference between groups I and II when third was compared with third; however, groups I and II had significantly more visible dentinal tubules than group III.     

二氧化氯作为根管超声冲洗剂的清洁效果

目的 评价二氧化氯用作根管超声冲洗剂的清洁效果.方法 选择30颗离体单根管前磨牙,截去牙冠后随机平分成A、B、C三组,用手持不锈钢器械逐步后退法进行根管预备,超声波冲洗,冲洗剂分别为蒸馏水、1.0%次氯酸钠和0.1%二氧化氯溶液.完成根管预备后纵行劈开牙根,扫描电镜观察,在根管颈1/3、中1/3、尖1/3各部位随机拍照,在电镜照片上评定根管壁上碎屑和玷污层记分,计数牙本质小管开放数目,并进行统计学分析.结果 A、B、C各组碎屑记分差异无统计学意义(P＞0.05);B、C两组的玷污层明显少于A组,差异有统计学意义(P＜0.01);牙本质小管开放数也明显多于A组,差异有统计学意义(P＜0.01),但B、C两组之间差异无统计学意义(P＞0.05).结论 0.1%二氧化氯溶液用作根管超声冲洗剂,具有良好的清洁作用,对碎屑和玷污层的去除能力不亚于1.0%次氯酸钠,明显优于蒸馏水.     

The effect of application time of EDTA and NaOCl on intracanal smear layer removal: an SEM analysis

AIM: To verify, under the scanning electron microscope (SEM), the influence of irrigation time with ethylenediaminetetraacetic acid (EDTA) and sodium hypochlorite (NaOCl) on intracanal smear layer removal. METHODOLOGY: Twenty-one extracted human permanent teeth with single straight root canals were included. The root canals of the teeth were instrumented and, at the end of preparation, were irrigated with 3 mL of 15% EDTA, followed by 3 mL of 1% NaOCl for 1 min (group 1), for 3 min (group 2), and for 5 min (group 3). The canals of teeth in group 4 (control) did not receive the final irrigation. The teeth were sectioned longitudinally and prepared for an SEM. The dentinal wall of cervical, middle and apical thirds was graded according to the amount of debris and smear layer remaining on the walls. The results were analysed using the Kruskal-Wallis and Conover-Inman tests. RESULTS: In all the canals of experimental groups irrigation with EDTA and NaOCl completely removed the smear layer from the cervical and middle thirds. In the apical third, the dentine surface were partially covered, particularly in the teeth of group 1, where there was significantly more smear layer when compared with the other thirds in the same group (P<0.007). However, the Kruskal-Wallis test showed overall that there were no significant differences between groups 1, 2 and 3 (P>0.05). CONCLUSION: In this limited laboratory study, canal irrigation with EDTA and NaOCl for 1, 3 and 5 min were equally effective in removing the smear layer from the canal walls of straight roots.     

Efficacy of various concentrations of NaOCl and instrumentation techniques in reducing Enterococcus faecalis within root canals and dentinal tubules

AIM: To evaluate the efficacy of 0.5%, 2.5% and 5.25% sodium hypochlorite (NaOCl) as intracanal irrigants associated with hand and rotary instrumentation techniques against Enterococcus faecalis within root canals and dentinal tubules. METHODOLOGY: A total of 180 extracted human premolar teeth were infected for 21 days with E. faecalis. The specimens were divided into 12 groups, as follows: group 1: 5.25% NaOCl + Hybrid technique (Valdrighi et al. 1998); group 2: 5.25% NaOCl + nickel-titanium (NiTi) rotary technique 4 mm shorter than the apex (by FOP-UNICAMP); group 3: 5, 25% NaOCl + NiTi rotary technique (Hero 642); group 4: 2.5% NaOCl +Hybrid technique; group 5: 2.5% NaOCl + NiTi rotary technique 4 mm shorter than the apex; group 6: 2.5% NaOCl + NiTi rotary technique (Hero 642); group 7: 0.5% NaOCl + Hybrid technique; group 8: 0.5% NaOCl + NiTi rotary technique 4 mm shorter than the apex; group 9: 0.5% NaOCl + NiTi rotary technique (Hero 642); group 10: sterile saline solution + Hybrid technique; group 11: sterile saline solution + NiTi rotary technique 4 mm shorter than the apex; group 12: sterile saline solution + NiTi rotary technique (Hero 642). Canals were sampled before and after preparation. After serial dilution, samples were plated onto brain heart infusion (BHI) agar, and the colony forming units (CFU) that were grown were counted. The teeth were sectioned into three thirds and dentine chips were removed from the canals with conical burs. The samples obtained with each bur were immediately collected into test tubes containing BHI broth, and were incubated at 37 degrees C and plated onto BHI agar. The CFU were counted and analysed. RESULTS: At all depths and thirds of the root canals and for all techniques used, 5.25% NaOCl was shown to be the most effective irrigant solution tested when dentinal tubules were analysed, followed by 2.5% NaOCl. No differences among concentrations in cleaning the canals were found. CONCLUSIONS: Especially at higher concentrations, NaOCl, was able to disinfect the dentinal tubules, independent of the canal preparation technique used.     

NaOCl and EDTA irrigating solutions for endodontics: SEM findings.

Premolars roots of humans were manually instrumented with K-type files and irrigated with different solutions to evaluate the rate of cleaning of endodontic surface. Root canals irrigated with 0.9% saline solution or H2O2 (10 volumes) showed the presence of predentin and amorphous smear layer. Thick smear layer was always present on endodontic walls rinsed with 5% solution of NaOCl. Specimens treated with 0.2% solution of EDTA showed partially clean dentinal tubules orifices and remnants of a thin smear layer. Occasional uninstrumented areas of the same roots presented smear layer remnants and predentin with calcified bacteria. The root canals irrigated with NaOCl and EDTA solutions alternated after each instrument showed at the dentin surface thick smear layer: only few dentinal tubules orifices were visible. Endodontic surface of root canals irrigated with NaOCl during instrumentation and finally rinsed with EDTA solutions showed the most homogeneous ultrastructural pictures: partially clean dentinal orifices were detectable in the whole canals.     

Effect of endodontic irrigation on bonding of resin cement to radicular dentin

The influence of endodontic irrigation on shear bond strengths of resin cement to radicular dentin was investigated. Human radicular dentin blocks were divided into four groups and subjected to one of four endodontic irrigations: ethylenediaminetetraacetic acid (EDTA) group, 17% EDTA for 60 s; EDTA/sodium hypochlorite (NaOCl) group, 17% EDTA for 60 s followed by 10 ml of 5% NaOCl for 15 s; NaOCl group, 10 ml of 5% NaOCl for 15 s; and control group, no treatment. Morphological changes of dentin surface after endodontic irrigation were observed by scanning electron microscopy (SEM). A resin block was bonded to the radicular dentin after irrigation using resin cement with either wet-bonding (Uni-Etch/One-Step; Bisco) or self-etching (Tyrian SPE/One-Step Plus; Bisco) adhesives. Shear bond strengths were measured and the penetration of resin tags into dentinal tubules at resin-dentin interface was observed by SEM. With the wet-bonding system, the shear bond strengths for the EDTA/NaOCl group, in which dentinal tubules openings and uniform resin tag penetration into dentinal tubules were observed, were significantly higher than the EDTA and control groups. With the self-etching system, the shear bond strengths were significantly lower in the EDTA group compared with the NaOCl and control groups. The effects of endodontic irrigation on the bonding of resin cement to radicular dentin depended on the dentin bonding system used.