次氯酸钠作为根管冲洗液的研究进展

目前国内在根管治疗中,多交替使用体积分数为3%的过氧化氢溶液和生理盐水冲洗根管,但此方法存在许多缺陷。次氯酸钠因有较强的杀菌性及组织溶解性,在国外普遍应用于根管冲洗中,但由于它具有较强的刺激性和腐蚀性,而国内尚未普遍应用橡皮障,因此限制了次氯酸钠在国内的应用。本文就次氯酸钠作为根管冲洗液的研究进展作一综述。     

根管冲洗剂次氯酸钠和氯亚明的细胞毒性

目的:评价次氯酸钠(NaOCl)和氯亚明溶液在相同有效氯浓度下的细胞毒性.方法: 按有效氯浓度为0.500 0%、0.250 0%、0.200 0%、0.150 0%、0.125 0%、0.062 5%分别配制NaOCl溶液和氯亚明溶液,使其与L929细胞接触2 h、30 min、10 min,用MTT法检测各组的细胞存活率.结果: 在所设定的浓度范围内,除高低两端组(0.500 0%-2 h及0.062 5%-30 min)外,细胞在其余各组NaOCl溶液中的存活率均大于氯亚明,差异有统计学意义(P<0.05).结论: 在0.250 0%以下的有效氯浓度范围,NaOCl溶液的细胞毒性小于氯亚明溶液.     

次氯酸钠对根管内粪肠球菌杀菌效果的体外实验

目的评价次氯酸钠对根管内粪肠球菌的杀菌效果。方法将45个离体前磨牙的感染根管标本分为6组，1、2组用5．25％及2．5％次氯酸钠冲洗，3组用0．9％NaCl冲洗，4、5组在根管预备时辅以5．25％及2．5％次氯酸钠冲洗，6组在根管预备时辅以0．9％Nacl冲洗。冲洗前、冲洗后即刻及冲洗后72h分别取样培养。结果6组根管内的细菌量均显著下降。1、2组差异无统计学意义（P〉0．05），但均好于3组（P〈0．05）。4、5和6组差异均有统计学意义（P〈0．05）。根管冲洗后培养72h均有细菌生长。结论2．5％次氯酸钠基本可达到更高浓度的灭菌效果，但是经过机械预备和次氯酸钠化学消毒后的根管内仍有细菌残留。     

次氯酸钠在根管清理中作用的研究进展

次氯酸钠因有较强的抑菌能力和组织溶解能力,常在临床上最常使用的冲洗剂的原因.本文对次氯酸钠在根管清理中的作用、作用机制及影响因素作一综述,介绍次氯酸钠在根管清理中作用的研究进展.     

双氧水、碘伏、次氯酸钠和乙二胺四乙酸清洁根管的效果比较

目的：比较双氧水、碘伏、次氯酸钠和乙二胺四乙酸清洁根管的效果。方法：将40个离体单根管牙随机分为4组,每组10个牙,经常规根管机械预备后应用不同的根管冲洗液冲洗根管：A组用3％过氧化氢;B组用0．5％碘伏;C组用5．25％的次氯酸钠;D组用15％乙二胺四乙酸。然后劈开牙根,用扫描电镜进行观察、评级。结果：D组的冲洗效果与A、B、C组有高度显著性差别（P〈0．01）;B、C组与A组之间的冲洗效果有高度显著性差别：（P〈0．01）;B组与C组的冲洗效果无显著性差别（P〉0．05）。结论：碘伏作为根管冲洗剂具有较好的临床应用价值。     

根管消毒效果检测研究的进展

根管消毒在根管治疗中极其重要。有效的根管消毒可彻底消除牙本质小管及侧支根管内的细菌，提高根管治疗的成功率。因此，根管药物否达到根管消毒的效果是临床医生关注的问题，本文就对根管消毒效果的评价方法做一综述。     

乙二胺四乙酸联合次氯酸钠冲洗C形根管的疗效观察

目的评价乙二胺四乙酸(ethylene diamine tetraacetic acid,EDTA)联合次氯酸钠冲洗根管对C形根管的临床疗效。方法选择C形根管的下颌第二磨牙慢性根尖周炎60例60颗,随机分成2组各30颗,常规Protaper镍钛器械预备根管,试验组采用EDTA联合次氯酸钠冲洗根管,对照组采用双氧水和生理盐水交替冲洗根管,两组患牙均采用热牙胶垂直加压充填,完成根管治疗。半年、1年后回访,观察临床疗效并进行统计学分析。结果半年后60颗患牙回访,试验组与对照组相比,患牙临床症状轻,X线片显示根尖周组织愈合好,试验组成功率为73.3%,对照组43.3%,差异有统计学意义(χ2=5.809,P=0.016);1年后回访57颗,2组治疗成功率均有上升,试验组为92.9%(26/28),对照组为72.4%(21/29),差异有统计学意义(χ2=3.912,P=0.048)。结论EDTA联合次氯酸钠冲洗根管对下颌第二磨牙慢性根尖周炎的C形根管效果良好。     

次氯酸钠对粪肠球菌杀菌效果的体外研究

目的体外评价次氯酸钠(NaOCl)对粪肠球菌的杀菌效果及浓度依赖关系。方法采用纸片扩散法药敏实验观察NaOCl对粪肠球菌的抑菌环大小(mm),直接接触法观察NaOCl对粪肠球菌的灭活时间。结果5.25%NaOCl的抑菌环直径最大,4.00%与2.50%、1.00%与0.50%差异无显著性。5.25%NaOCl在30s内可杀死全部粪肠球菌,2.50%NaOCl杀死粪肠球菌需要15min,随浓度的下降,杀死细菌所需要的时间延长。结论高浓度NaOCl的效果优于低浓度NaOCl,2.50%NaOCl基本可满足临床要求。     

不同根管冲洗剂对根管玷污层清洗效果的体外研究

目的 比较不同根管冲洗剂对根管内壁玷污层的清洗效果.方法 将32颗离体牙随机分成4组,每组8颗,A组0.9％生理盐水冲洗,B组3％双氧水冲洗,C组3％次氯酸钠冲洗,D组2％氯亚明冲洗.根管预备完成后,扫描电镜观察根管中1/3的玷污层去除情况,参考玷污层分级标准,对数据进行统计学分析,比较各组根管玷污层清洗效果.结果A、...     

四种根管消毒剂对乳牙根管消毒作用的临床观察

目的：对比大蒜素、甲硝唑、甲醛甲酚（FC）、樟脑酚（CP）4种根管消毒药物,对乳牙感染根管消毒作用的应用前景,从中选出较适用于乳牙感染根管的消毒药物。方法：选择2．5～8岁患儿乳牙牙髓炎、根尖周炎160例共168个牙,随机分成4组,分别封人大蒜素、甲硝唑、FC、CP,7d复诊,观察临床疗效。结果：4种根管消毒剂对乳牙感染根管的消毒作用,大蒜素组有效率90％,甲硝唑组有效率88％;FC组有效率89％;三组间比较无显著性差异（P〉0．05）,CP组有效率77％。组间比较有显著性差异（P〈0．05）,4种根管消毒药物与牙位无显著性差异,4组病例中FC组出现2例治疗期间急症,对有瘘型根尖炎大蒜素和甲硝唑组与FC和cP组比较有显著性差异。结论：4种根管消毒药物应用于乳牙感染根管最佳选择依次为大蒜素,甲硝唑、甲醛甲酚、樟脑酚。     

几种根管冲洗液组合对粪肠球菌感染根管体外抗菌研究

目的：比较本实验室研制的根管润滑剂与不同浓度次氯酸钠组合用于粪肠球菌感染根管预备冲洗的抗菌效果。方法：将145颗单根管人离体牙消毒,随机选取5颗置于无菌培养基中培养作为阴性对照,其余140颗接种粪肠球菌4周,按照不同的冲洗组合随机分为14组,使用ProTaper器械按照冠根向深入法进行机械预备,分别在预备冲洗前、预备冲洗中和预备冲洗后进行细菌取样培养计数,并进行统计学分析。结果：与双氧水联合生理盐水组以及蒸馏水对照组相比,各处理组在冲洗过程中与冲洗结束后,均不同程度的降低了根管中的细菌的数量,其中含5.25%次氯酸钠的四种组合处理后菌数减少最为明显,较其它各组差异显著。结论：本实验室研制的根管润滑剂与5.25%次氯酸钠组合抗菌效果最佳,与G lyde凝胶配合次氯酸钠组没有显著差异。     

Antimicrobial Efficacy of Chlorhexidine and Sodium Hypochlorite in Root Canal Disinfection: A Systematic Review and Meta-analysis of Randomized Controlled Trials

IntroductionWe aimed to compare the antimicrobial efficacy of chlorhexidine (CHX) and sodium hypochlorite (NaOCl), 2 irrigants routinely used in root canal therapy of permanent teeth.MethodsElectronic databases, including PubMed, EMBASE, Web of Science, and Cochrane Library, were searched for randomized controlled trials published until March 2020. The meta-analysis of relative risk (RR) and standardized mean difference (SMD) was performed using a random effects model with a 95% confidence interval (CI). Subgroup analysis was performed for culture and molecular methods of bacterial detection.ResultsThe literature search yielded 2110 records without duplicates. Eight studies were eligible for a systematic review. No significant differences in the incidence of samples with positive bacterial growth after irrigation (RR = 1.003; 95% CI, 0.729–1.380; P = .987) and mean bacterial number changes (SMD = 0.311; 95% CI, −0.368 to 0.991; P = .369) were observed between CHX and NaOCl in the culture and molecular subgroups. Heterogeneity in RR (I² = 0%, P = .673) was low among studies, whereas considerable heterogeneity was observed in the analysis of SMD (I² = 76.336%, P = .005).ConclusionsOur findings suggest that both CHX and NaOCl can reduce bacterial infections after irrigation without any significant difference in antimicrobial efficacy between them. Although CHX and NaOCl showed similar efficacy, their molecular mechanisms were different. Therefore, they can be used as the main antibacterial root canal irrigants. However, our results were limited by inconsistencies among retrieved articles and a lack of clinically relevant outcomes. Further well-designed clinical studies are warranted to supplement our results.     

Root Canal Irrigants and Medicaments in Endodontic Malpractice Cases: A Nationwide Longitudinal Observation

Introduction

The aim of this study was to assess the role of root canal irrigants and medicaments in endodontic injuries verified in Finland and to estimate the rate of such events over time.

Sodium Hypochlorite Chemical Burn in an Endodontist's Eye during Canal Treatment Using Operating Microscope

Introduction

This study describes a case of eye burn induced by sodium hypochlorite used as an irrigant during root canal preparation.

Methods

A 24-year-old female endodontist was using an operating microscope during root canal treatment, and as the root canal was irrigated, the pressure cannula burst and the irrigant (3.5% sodium hypochlorite) came into direct contact with her left eye. She immediately sought ophthalmologic emergency care for pain, redness of the cornea, burning sensation, photophobia, intraocular pressure, and blurred vision. The initial treatment consisted of washing the eye with saline solution and administering analgesic and anti-inflammatory (steroid) medications. One day after the accident, a topical demulcent and hydroxypropyl medication were applied to the eyeball (conjunctiva), the eye was bandaged for 24 hours, and rest was prescribed for 7 days. Eight days later, a corneal ulcer was diagnosed, and antibiotic and anti-inflammatory (steroid) medications were used.

Results

Vision was restored without any sequelae 4 weeks after the accident. The endodontist was instructed to apply control medication (Lagricel; Sophia SA, Caracas, Venezuela) for 3 months and to return for ophthalmologic follow-up every 6 months.

Conclusions

Sodium hypochlorite is an effective antibacterial irrigant indicated for the treatment of root canal infections. The tissue cytotoxicity highlights the need to inform the patient of the risk factors of accidents and enhance care with individual protection equipment for the patient and the professional during clinical procedures.     

Er:YAG激光联合次氯酸钠对粪肠球菌杀菌效果的研究

目的:比较掺铒钇铝-石榴石脉冲(Er:YAG)激光联合不同浓度次氯酸钠对根管内粪肠球菌杀菌效果的研究。方法:选择新鲜拔除的人单根管离体前磨牙建立粪肠球菌根管感染模型75个,随机分为5组,每组15个,分别进行如下处理:A组:5.25%次氯酸钠单独冲洗;B组:Er:YAG激光+5.25%次氯酸钠冲洗;C组:1%次氯酸钠单独冲洗;D组:Er:YAG激光+1%次氯酸钠冲洗。E组:空白对照。采集5组根管内的细菌进行培养计数并对结果进行卡方检验(Chi-square test)。结果:A、B、D三组均能完全杀灭根管内的粪肠球菌;C组未能完全杀灭根管内的粪肠球菌。15个培养皿中有11个可见粪肠球菌菌落。A、B、D三组间杀菌效果无差异且均显著优于C组。结论:高浓度次氯酸钠可以完全杀灭根管内的粪肠球菌,低浓度次氯酸钠不能完全杀灭根管内的粪肠球菌;Er:YAG激光可以显著增强低浓度次氯酸钠的杀菌作用。     

超声根管预备和根管封闭剂对根尖微渗漏的影响

目的 了解超声根管预备和根管封闭剂对根管治疗后根尖微渗漏的影响。方法 将79颗离体牙随机分为5个实验组和2个对照组。实验组分别用超声波，回旋手机和手法备根后分别用AH plus^TM，根充I号，氧化锌糊剂作根管封闭剂并用牙胶法作侧压充填。用2％亚甲蓝浸泡1周后纵剖牙体，体视镜下观测染料渗透长度。数据行统计学分析。结果 三种备根方法中，超声备根组根尖微渗漏最少。三种根管封闭剂中，AH plus^TM组微渗漏最少。结论 超声根管预备后根充术，同时采用AH plus^TM根管封闭剂，能有效地减少根充术后微渗漏，提高根管治疗效果。     

口腔医学生临床前离体牙及人工根管根管治疗教学研究

目的：通过离体牙、人工根管培养实习医生了解并掌握根管治疗的标准程序和方法。方法：选择正畸患者拔除离体牙36颗、牙髓病及牙周病拔除离体牙42颗,人工根管4颗,分组采用常规改良逐步后退法、冠向逐步深入法进行根管处理、预备及充填,观察实习医生根管治疗掌握情况及模拟治疗效果。结果：离体牙采用改良逐步后退法时,前牙根管治疗成功率〉前磨牙〉磨牙（P〈0.05）;离体牙磨牙组中,采用冠向逐步深入法成功率高于逐步后退法（P〈0.01）。结论：采用人工根管可以直观的辅助实习医生体会弯曲根管的治疗,结合离体牙进行根管治疗训练可以提高加深实习医生对根管解剖结构、不同根管治疗方法的了解,对于实习医生临床前培养有明显效果。     

不同根管处理方法对根管壁抗折力影响的研究

目的　比较预备与不预备的根管以及预备后充填与不充填的根管抗折力。方法　将 30颗人尖牙随机分为 2个实验组和 1个对照组 ,每组 10颗。实验组从牙颈部截去牙冠后进行根管预备。第 1组以Ultra为封闭剂 ,采用冷侧压方法充填 ;第2组根管预备后不充填 ;第 3组根管不作任何处理。所有标本进行抗剪切强度试验。结果　第 2组与其他 2组间差异有显著性 (P <0 .0 0 1) ,抗折应力值最低 (12 6 .182MPa) ;第 1组抗折应力值最大 (15 3.4 97MPa) ;第 1组和第 3组之间无统计学差异 (P>0 .0 5 )。结论　预备后不充填的根管抗折力低于未处理组和完善根管治疗组。使用封闭剂根充后的管壁抗折力增强。     

Root Canal Disinfection by Single- and Multiple-instrument Systems: Effects of Sodium Hypochlorite Volume,Concentration, and Retention Time

IntroductionThis ex vivo study evaluated the intracanal bacterial reduction promoted by chemomechanical preparation using a single-file technique varying the volume, concentration, and retention time of sodium hypochlorite (NaOCl) irrigation in comparison with a multifile system.MethodsPalatal roots from extracted maxillary first molars were selected and anatomically matched based on microcomputed tomographic analysis for group distribution. The canals were contaminated with a fresh mixed bacterial culture grown in anaerobiosis and recently obtained from a tooth with apical periodontitis. Specimens were divided into 4 groups of 24 each according to the following preparation protocols: REC-6LOW (Reciproc R50 instrument [VDW, Munich, Germany], 6% NaOCl, low irrigant volume), REC-2.5LOW (R50, 2.5% NaOCl, low irrigant volume), REC-2.5HI (R50, 2.5% NaOCl, high irrigant volume), and BR-2.5HI (BioRaCe [FKG Dentaire, LaChaux-de-Fonds, Switzerland], 2.5% NaOCl, high irrigant volume). The total time of preparation was recorded. Intracanal bacteriologic samples were taken before and after preparation; DNA was extracted and subjected to quantitative polymerase chain reaction.ResultsBacteria were detected in 22 initial samples from the REC-2.5LOW group and in 23 from the other groups. Intragroup analysis showed that all tested preparation protocols were highly effective in significantly reducing the intracanal bacterial counts (P < .001). Intergroup comparison of bacterial reduction levels revealed a statistically significant difference between BR-2.5HI and REC-2.5LOW (P < .05). Counts of bacteria were 2.5 times significantly higher in REC-2.5LOW compared with BR-2.5HI. No other significant differences were found in quantitative findings (P > .05).ConclusionsThe concerted effects of multiple instruments, the high volume of irrigation, and the long retention time of NaOCl irrigant had a positive influence on intracanal disinfection during chemomechanical preparation.