应用显微超声技术清除根管内罕见异物的病例分析

目的 研究4例,临床上罕见的根管异物病例(2例缝被针及指甲,2例牙科用钻针)的临床清除过程.方法 应用根管显微镜,超声器械ET40松解异物旁根管壁牙本质,振松清除异物.结果 异物完全清除,完善根管治疗,患牙得以保存.结论 鉴于根管异物清除的复杂性,临床医生应具备正确识别根管异物的能力,通过准确定位并采用合适的方法,以达...     

Removal of resin-based root canal filling materials with K3 rotary instruments: relative efficacy for different combinations of filling materials

Removal of resin-based root canal filling materials may cause serious problems during root canal retreatment. This study compared the working time and amount of canal enlargement when different resin-based root canal filling materials were removed with K3 rotary instruments with or without heat-softening using System B. Root canal sealer/filling point combinations tested were Epiphany/Resilon, SuperBond/Resilon, SuperBond/gutta-percha, and Canals N/gutta-percha. The materials were filled into simulated curved resin canals and removed with K3 instruments in a standardized crown-down procedure. In terms of working time, Epiphany/Resilon required a significantly longer working time than the others. However, heat application with System B significantly reduced the working time for the removal of Epiphany/Resilon. In terms of canal enlargement, there were no significant differences among the tested groups as determined with digital morphometry. It was thus concluded that Epiphany removal with K3 rotary instruments might result in extended working time, but which could be reduced with heat-softening using System B.     

新型套索装置取根管内折断器械的体外评价

目的:通过体外实验,评估新型套索装置取根管内折断器械的疗效.方法:选择半年内拔除的完整下颌恒磨牙,拔除后保存于生理盐水中.要求根尖孔已闭合,无隐裂,冠根长18 mm以上,牙根弯曲角度小于90°.根管通畅后,将截短5mm的30#04锥度镍钛锉尖端折断3 mm于近颊根管中上段.离体牙随机分为套索组和超声组,每组20颗;套索...     

3种往复旋转单支镍钛器械预备模拟弯曲根管的效果比较

目的:评价3种往复旋转单支镍钛器械预备模拟弯曲根管的效果.方法:选择115个单弯树脂模拟根管,采用随机图表法分为Reciproc组(A组,28个)、One file组(B组,29个)、Wave One组(C组,29个)和对照组(D组,29个).按照说明书要求预备模拟根管,比较4组根管预备、树脂去除量、根管清理效果、中心...     

Anatomic determination of the mesiobuccal root resection level in maxillary molars

Surgical endodontics involving root resection/apical fill are often performed when retreatment by orthograde endodontic procedures are not possible. Because of the potential presence of accessory canals within the root, a preferred minimal root resection level should be investigated for the removal of the majority of these canals. One hundred fifty-three extracted, uninstrumented, mesiobuccal roots from first and second maxillary molars were examined for the presence of accessory canals, canal isthmus, and canal wall thickness. Three hundred ninety accessory canals were identified, with 80% of these canals located within 3.64 mm of the apex of the tooth. Canal isthmus was often not evident until 3.12 mm of the root was resected, with canal wall thickness only approximating 1 mm thick. The observations here suggest a minimal resection level to 3.6 mm for accessory canal incidence, canal isthmus detection, and canal wall thickness and provide a better understanding of maxillary mesiobuccal (MB) root anatomy for retrograde root resection/apical filling.     

根管弯曲度和器械分离位置对分离器械取出的影响

目的探讨根管弯曲度和器械分离位置对根管内分离器械取出的影响。方法选取60颗离体人下颌前磨牙,建立根管内不锈钢K型锉分离模型。根据器械分离于根管口下的深度（2、8 mm）和分离角度（20°、30°、40°）分为6组,每组10颗。采用超声法取出分离的K型锉,记录K型锉的取出数和操作时间,使用图像分析软件将术前术后拍摄的数码X线片重叠,测量分离器械取出前后K型锉冠端处根管直径的变化值。结果6组不锈钢K型锉全部取出,未发生侧穿。分离位置一定时,随着弯曲度的增大,取出分离K型锉时冠端处横向牙本质切削量增大,差异有统计学意义（P<0.05）,取出时间无明显变化（P>0.05）;而弯曲度一定时,随着分离深度的增加,取出时间明显增加（P<0.05）,分离K型锉冠端处横向牙本质切削量无明显变化（P>0.05）。结论根管弯曲度越大,分离器械冠端处横向牙本质切削量越大;分离位置是影响分离器械取出的重要因素,但并不影响分离器械冠端处横向根管壁的牙本质切削量。安全有效的直线通路和足够的牙本质厚度是成功取出根管内分离器械的必要条件。     

Root canal cleaning in roots with complex canals using agitated irrigation fluids

The internal topography of the root canal is complex, especially for the mesial root of the permanent first molar. In response to such challenges, enhanced irrigation protocols have been developed, using laser pulses to agitate fluids and enhance the removal of microbial deposits. The aim of this laboratory study was to assess the effectiveness of laser agitation of sodium hypochlorite in removing multispecies biofilms grown in the mesial root of the permanent first molars. The five agitation groups (N = 12 roots for each) were: 940 nm diode laser (superpulsed mode, 50 μs/pulses at 20 Hz using 20 mJ/pulse); 1064 nm Nd: YAG laser (200 μs/pulse at 20 Hz using 20 mJ/pulse); 2940 nm Er: YAG laser (50 μs/pulse at 15 Hz using a 400/14 conical tip in the SWEEPS protocol, with 20 mJ/pulse); passive ultrasonic agitation at 28 kHz (positive control); and irrigation with a 27-gauge side vented needle for 2 min per canal (negative control). Biofilm removal was assessed by confocal microscopic imaging of root slices at 1, 4 and 7 mm from the root apex. None of the tested methods were effective in completely eradicating biofilm from the most confined regions of the root canal system. The greatest challenge was cleaning the isthmus regions. There was a positive correlation between canal cleaning and isthmus cleaning, suggesting that increased effectiveness in cleaning root canal walls is associated with more effective isthmus cleaning. Wider and narrow isthmuses were cleaned better than long and narrow isthmuses.     

Removal of root filling materials

Safe, successful and effective removal of root filling materials is an integral component of non‐surgical root canal re‐treatment. Access to the root canal system must be achieved in order to negotiate to the canal terminus so that deficiencies in the original treatment can be rectified. Since a range of materials have been advocated for filling root canals, different techniques are required for their removal. The management of commonly encountered root filling materials during non‐surgical re‐treatment, including the clinical procedures necessary for removal and the associated risks, are reviewed. As gutta‐percha is the most widely used and accepted root filling material, there is a greater emphasis on its removal in this review.     

微波对化学法根管预备中的玷污层的影响

目的:研究微波是否能增强EDTA在联合次氯酸钠对根管玷污层的作用.方法:9个离体的单根管前磨牙随机编号,分为A、B、C 3组,去冠后沿牙体长轴将牙根一分为二劈开,暴露根管,将牙的每一半再各编为微波组和对照组,各组依次17?TA和1%NaOC1冲洗,微波组另增加不同时间的微波照射.结果:电子显微镜下观察,在去除根管玷污层效果上微波组明显好于对照组(P＜0.05).结论:微波能促进EDTA在联合次氯酸钠对根管玷污层的作用.     

Two patients requiring surgical management for leakage of calcium hydroxide paste from root canal into infraorbital space

Two patients requiring surgical management for leakage of calcium hydroxide paste from a root canal into the infraorbital space are reported. A paste root canal treatment material used at the time of maxillary root canal treatment had leaked out of the root canal in both patients. Computed tomography confirmed displacement of the root canal treatment material into the soft tissue, with extension into the infraorbital space. In both cases, foreign body removal was performed. Root canal treatment using a calcium hydroxide paste should be performed carefully without strong pressure.     

Sealing root canals with low-viscosity resins in vitro: a scanning electron microscopy study of canal cleansing and resin adaption

Low-viscosity resins of the fissure sealant type have been suggested in the literature as having potential for use as root canal filling materials. A low-viscosity resin may seal a root canal by flowing into clean dentinal tubules after smear layer removal. This investigation with scanning electron microscopy examines the efficacy of two methods of root canal preparation and the effectiveness of different chemicals on smear layer removal. Ultrasonic preparation with 0.25% sodium hypochlorite solution and final agitation with 50% citric acid solution were found to produce a very clean canal wall, free of smear layer in coronal and middle parts. However, low-viscosity resin used in conditions that aimed to simulate in vivo conditions failed to penetrate open dentinal tubules to a significant extent. On the basis of these observations made with scanning electron microscopy, low-viscosity resins would not seem suitable as root canal filling materials, because they are unlikely to form a satisfactory adaption to the canal wall. In addition, if treatment fails, these resins are impossible to remove from a root canal without much destruction of tooth substance.     

数字化根管定位导板应用于完全钙化根管的临床报道1例

髓腔完全钙化的牙齿需要行根管治疗时,精确定位并疏通钙化根管、避免侧穿是困扰临床医生的一大难题.随着锥形束CT、口内扫描和3D打印技术的逐步成熟,数字化根管定位导板技术可以通过计算机辅助设计定位到狭窄的根管通路,最大程度地保存牙体组织,提高根管治疗的安全性和成功率,该文报道1例将数字化根管定位导板应用于髓腔完全钙化的前牙...     

椅旁四面体定位技术制作导板拆除纤维桩1例及文献复习

目的 探讨椅旁四面体定位技术制作导板拆除纤维桩的技术和效果.方法 对1例左上颌侧切牙慢性根尖周炎急性发作且需拆除纤维桩的患者,使用椅旁四面体定位技术制作导板拆除纤维桩.将锥形束CT(cone beam CT,CBCT)数据导入软件进行纤维桩拆除导板设计,利用四面体定位技术,将CBCT上的导板设计转移到实体模型上,制作导...     

Adhesion of a glass-ionomer root canal sealer to the root canal wall

Glass-ionomer root canal sealer is commonly used because of its chemical bonding and favorable physical characteristics when bonding to dentin. This study was designed to determine the tensile bond strength of a glass-ionomer sealer (Ketac Endo, Espe, Seefeld, Germany) on root canal walls after pretreatment with different conditioners. Flat inner surfaces of root canal specimens were prepared. The specimens were divided into five groups of 10 teeth, and the groups were conditioned with one of the following smear layer removal solutions: 15% EDTA/NaOCl, 10% polyacrylic acid, 35% phosphoric acid, 6% citric acid, and 5.25% NaOCl as a control. Then the exposed root canal areas were coated with Ketac-Endo. Tensile bonding was measured using a universal testing machine until ultimate failure was obtained. The groups that were treated with phosphoric acid and citric acid showed significantly higher bond strengths than the groups that were treated with 15% EDTA and polyacrylic acid (p < 0.05). Bonding to dentin without smear layer removal (NaOCl group) was too low to be measured in the testing apparatus. Scanning electron microscopy confirmed that phosphoric and citric acids were more effective in removing smear layer than EDTA or polyacrylic acid. The result supported the view that pretreatment with phosphoric acid or citric acid should be used in association with glass-ionomer root canal sealer to achieve the most effective removal of the smear layer and to provide better adhesion.     

臭氧水溶液去除根管内玷污层的扫描电镜观察

目的：观察臭氧水溶液对根管内玷污层的去除效果。方法：40颗离体单根牙随机分为5组,应用逐步后退法进行根管预备。A组：2.15 mg/L臭氧水溶液组;B组：3%过氧化氢加生理水组;C组：2.15 mg/L臭氧水溶液加1%次氯酸钠组;D组：17%EDTA加5.25%次氯酸钠组（阳性对照组）;E组：三蒸水组（阴性对照组）。根管预备过程中使用各冲洗液冲洗根管,然后将牙体沿牙体长轴纵向劈开,并应用扫描电镜对根管中1/3进行观察,结果进行统计学分析并摄片。结果：17%EDTA加5.25%次氯酸钠组去除玷污层效果最好,但有牙本质小管口增宽和管间牙本质过度脱矿现象。2.15 mg/L臭氧水溶液组对根管玷污层有一定去除作用,而2.15 mg/L臭氧水溶液加1%次氯酸钠组对玷污层的去除能力优于单纯臭氧水溶液组。3%过氧化氢液加生理盐水组和三蒸水组对玷污层能力很小,但双氧水组稍好于三蒸水组。结论：2.15 mg/L臭氧水溶液具有去除根管玷污层的潜力,将该浓度臭氧水溶液和次氯酸钠联合使用对根管玷污层有一定去除作用,且对牙本质无腐蚀作用。     

3D打印数字化定位导板在根管再治疗中的应用效果评价

目的：探讨3D打印数字化定位导板在根管再治疗中的应用效果。方法 ：选取2018年1月—2021年12月赤峰学院附属医院收集的82颗离体牙，以随机数字表法分实验组和对照组，各41颗。2组均行根管再治疗，对照组行传统开髓，实验组在3D打印数字化定位导板下精准开髓。比较2组冠部修复体损伤情况，记录开髓操作时间，统计2组根管内充填物去除情况、牙体组织抗折性能和并发症发生率。采用SPSS 18.0软件包对数据进行统计学分析。结果：实验组开髓孔面积与面总面积比值显著低于对照组（P<0.05），开髓时间显著少于对照组（P<0.05）、根管预备时间显著多于对照组（P<0.05）;2组开髓与根管预备总时间相比，差异无统计学意义（P>0.05）。实验组根管内充填物去除率显著高于对照组（P<0.05）、破坏载荷值显著高于对照组（P<0.05）。2组并发症发生率相比，差异无统计学意义（P>0.05）。结论：3D打印数字化定位导板用于根管再治疗，可实现精准微创开髓，减少冠部修复体损伤，保留更多牙体组织，提高去除根管充填物效率及牙体组织的抗折性能。     

The effect of four different irrigation systems in the removal of a root canal sealer

Objectives

The aim of this study was to compare the efficiency of sonic, ultrasonic, and hydrodynamic devices in the removal of a root canal sealer from the surface and from simulated irregularities of root canals.

Materials and methods

Fifty-three root canals with two standardized grooves in the apical and coronal parts of longitudinally split roots were covered with AH Plus root canal sealer. Compared were the effects of (control) syringe irrigation, (1) CanalBrush, (2) passive ultrasonic irrigation, (3) EndoActivator, and (4) RinsEndo on the removal of the sealer. The specimens were divided into four groups (N?=?12) and one control group (N?=?5) via randomization. The amount of remaining sealer in the root canal irregularities was evaluated under a microscope using a 4-grade scoring system, whereas the remaining sealer on the root canal surface was evaluated with a 7-grade scoring system.

Results

Passive ultrasonic irrigation is more effective than the other tested irrigation systems or syringe irrigation in removing sealer from root canal walls (p?Conclusions Within the limitations of this study protocol ultrasonic irrigation shows a superior effect on sealer removal from the root canal surface during endodontic retreatment. Cleaning of lateral grooves seems not to be possible with one of the techniques investigated.

Clinical relevance

Incomplete removal of root canal sealer during re-treatment may cause treatment failure. Passive ultrasonic irrigation seems to be the most effective system to remove sealer from a root canal.     

Anatomical differences in lower third molars visualized by 2D and 3D X-ray imaging: clinical outcomes after extraction

The purpose of this study was to evaluate the relationship between third molars and the inferior alveolar canal using panoramic radiographs and cone beam computed tomography (CBCT) scans and to assess clinical outcomes after third molar removal retrospectively. The degree of superimposition, buccolingual position (buccal, central, and lingual) and physical relationship (separation, contact, and involved) were measured using CBCT scanning. Post-extraction complications were recorded. Based on radiographic evaluation, 45.9% of third molar roots were inside the inferior alveolar canal, 21.3% were in contact with the inferior alveolar canal, and 32.8% were separated from the canal. The frequency at which the mandibular canal was separated from the root apex was significantly higher when the canal was in the buccal position (80.0%) than in the central (20.0%) and lingual positions (0.0%). Although on panoramic radiographs all third molars were directly superimposed on the inferior alveolar canal, CBCT showed direct contact or canal involvement in 67.2% and separation of the canal from the root apex in 32.8%. Complications occurred in nine patients: eight had third molar root apices inside or in contact with the inferior alveolar canal. The prevalence of post-extraction complications correlated with the absence of cortication around the inferior alveolar canal.     

镍钛器械预备根管对牙根抗折性影响研究进展

根管治疗术是牙髓病和根尖周病的首选和重要的治疗方法,治疗后常见并发症之一是牙根折裂。根管治疗术中的每一个步骤都有可能影响牙根的抗折性。根管预备因涉及牙本质的去除、根管形态结构的改变,更有可能危及牙根的抗折强度。近几年随着根管治疗技术的发展,镍钛器械已用于根管预备,镍钛器械一般锥度较大,预备出的根管有更好的冠部扩展,但牙本质壁变薄,会增加根管充填时发生根折的危险性。目前,针对镍钛扩根器械对牙体抗折性能的影响存在不同观点。本文就不同镍钛器械预备根管对牙根抗折性的影响做一综述。     

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提要：根管预备目的是通过根管清理彻底去除根管内坏死组织、细菌及其代谢产物、牙本质碎屑，并为根管严密充填建立理想形态。如处理不当会导致根管偏移、台阶形成、根管堵塞、根管侧穿、器械折断等。第三部分主要介绍根管预备操作失误，旨在为临床医生提供理论和实践参考。