连续横截离体牙对C形根管形态的研究

目的：研究C形根管根管口及横断面形态的变化。方法：收集具有C形根管解剖外形的上下颌第二磨牙、下颌智齿、下颌第一前磨牙206颗,用硬组织切片机从根管口向根尖方向每隔0.5 mm连续横切,在显微镜下观察其根管口及根管横断面形态的变化。根据Melton的方法进行分类。结果：206颗C形根管中,C1型根管口59颗,占28.64%;C2型为114颗,占55.34%;C3型33颗,占16.02%。根管横断面形态从根管口到根管中下段形态变化不定。结论：C形根管形态复杂多变,临床行根管治疗时难度较大。     

切牙神经管的解剖学特点

目的　研究国人切牙神经管的位置及下颌管、颏管的关系 ,为临床手术提供解剖学数据。方法　据开 60侧湿下颌骨标本 ,对下颌管前端、颏管和切牙神经管进行直接观察和测量。结果　在下颌管前端分出颏管和切牙神经管。切牙神经管的管径为 1.76± 0 .2 6mm ,其下缘至下颌骨下缘的垂直距离为 9.5 3± 1.43mm ,始端对应颏孔前缘的水平距离为 3 .5 4± 0 .72mm。切牙神经管内为切牙神经 ,主要分布到下颌前牙。结论　颏管和切牙神经管由下颌管发出 ,颏管向后、上、外转弯上行 ,切牙神经管向前行     

Preparation of simulated root canals using the Macfile, Canal Master U and K-Flexofile

The efficacy of three different root canal instruments in maintaining the original shape of curved canals was evaluated. Acrylic blocks were prepared to simulate canals with 40° and 60° curvature. K-Flexofiles and Macfiles were used with a step-back technique utilizing an 'in/out' filing motion. The balanced-force technique was used with Canal Master 'U' instruments. Ten 40° and 10 60° canals were prepared with each instrument. The results were evaluated using superimposed photographic slides at ×20 magnification to show the canals before and after the instrumentation. The width of the prepared canals was measured at their convex/concave point to determine the divergence of the instrumented canal shape from the original canal shape. The measurements were taken at the level of the apical foramen and 3 and 6 mm coronal to it. In this way it was possible to recognize all the defects created during the preparation of a canal. Among the tested instruments, the Macfile provoked minimal canal deviation ( P = 0.05). The Canal Master 'U' was similarly effective ( P = 0.05), but had the highest incidence of instrument fracture. The K-Flexofile demonstrated the most defects in canal preparation and canal deviation, particularly at the level of the apical foramen ( P < 0.01).     

Assessing the shape of root canals: an in vitro method using microradiography

The aim of this paper is to describe an in vitro method which provides clear and accurate details of root canal shape. The method utilizes the technique of contact microradiography to produce high resolution, two-dimensional, real-size images of canals in a longitudinal plane. Specimens can be accurately rotated through 90° allowing images to be produced in a bucco-lingual and mesio-distal direction. The method is simple, relatively rapid and can process large numbers of teeth without the need for complicated and expensive mounting blocks or film holders. The technique can be used to produce pre- and post-operative images of canal shape which can be superimposed to delineate the dentine removed during canal preparation. The method is thus suitable for the evaluation of the shaping ability of endodontic instruments and preparation techniques.     

预备弯曲根管时根管偏移的实验研究

目的：定量研究弯曲根管预备过程中根管的偏移。方法：使用不锈钢K锉按常规法预备8个弯曲人工根管，根管预备过程中对根管、根尖孔进行微距摄影，用图像分析软件Image—Pro Plus对根管的形态和位置变化进行测量、分析。结果：根管预备时随着锉号的递增，弯曲根管逐渐被拉直，表现为根管弯曲角度逐渐减小，弯曲半径、根管轮廓面积逐渐增大，根管口、根尖孔被拉开，根管壁出现3个过度切削区。结论：预备弯曲根管时，根管不同部位的偏移方向、偏移距离并不相同，掌握弯曲根管的解剖形态以及根管器械的力学性能，有助于准确估计根管偏移的大小和方向。     

223例阻塞根管的根管预备路径分析

目的 通过对223例阻塞根管进行根管预备的分析,总结出对阻塞根管预备的有效方法和一般规律.方法 将阻塞根管223例根据阻塞原因分成根管钙化、塑化治疗、根管治疗、其他治疗和器械折断5组,应用机械预备加化学预备、超声根管预备以及溶塑剂、溶根充等处理,配合探寻锉预弯、截短等技巧的使用进行根管预备,将预备结果分组记录,并进行统计分析.结果 223例阻塞根管预备成功209例,获得较高的成功率(93.7%).其中根管钙化组成功率93.2%;塑化治疗组成功率87.2%;根管治疗组成功率97.7%;其他治疗组成功率93.3%;器械折断2例均获得成功,其中塑化治疗组成功率低于根管治疗组(P＜0.05).结论 手持器械预备加化学预备,以及超声预备辅以探寻锉预弯、截短等技巧,用于阻塞根管的预备可获得满意的结果,塑化治疗再预备的成功率较低.     

不同扩根器械拆除根管充填物的比较研究

目的比较不同器械在进行根管再治疗时拆除根管充填物的能力.方法选取48颗离体上前牙常规根管治疗后随机分为4组(每组12颗),进行根充物的拆除.记录到达工作长度牙数、到达工作长度用时、根充物推出根尖孔牙数、发生并发症牙数及器械损耗数.最后纵劈牙齿,统计根管内残余充填物量.实验结果采用ANOVA和X-检验.结果H锉联合回旋手机组到达根尖工作长度用时最短,与其它组间存在显著性差异(P＜0.01);四组根管内都有充填物残余;根管冠、中1/3的清理效果各组间无显著性差异(P＞0.05),而在根尖1/3处H锉联合回旋手机组的清理效果好,与其它组间存在显著性差异(P＜0.05);K锉联合回旋手机组有侧穿发生.结论H锉拆除根充物速度快、清理效果好;联合使用回旋手机可提高工作效率,但有一定的潜在风险,应谨慎操作.     

超声技术应用于弯曲细小和堵塞根管的治疗分析

目的对弯曲、细小和堵塞根管的处理方法和疗效作出评价。方法应用超声技术对７３例弯曲、细小和堵塞根管的处理进行临床观察分析。结果根管扩大并完成根管充填６９例，成功率９４．５％，未出现牙折、侧穿、断锉等情况；失败４例，均为堵塞根管。结论证实了超声根管治疗的有效性、安全性和实用性，但在处理弯曲根管方面由于其成形作用较差，故尚有一定的局限性。     

不同根充糊剂根尖封闭性的比较研究

目的　比较不同根充糊剂根管充填后的根尖封闭性。方法　 79颗离体单根牙随机分为阳性对照 (2颗 )、阴性对照 (2颗 )及 5个实验组 (各 15颗 ) ,分别用不同的根充糊剂加牙胶尖以冷侧压法充填根管 ,通过染料渗入法检查根尖微渗漏。结果　所有根充糊剂充填后根尖部位均有微渗漏 ,Vitapex组的微渗漏值低于其他各组 ,差异有显著性 (P <0 .0 5 ) ,而其余各组结果差异无显著性 (P >0 .0 5 )。结论　各种根充糊剂充填后都不能完全封闭根尖孔 ,Vitapex的根尖封闭性优于其他各组。     

联合侧向热垂直加压技术充填根管初探

目的:探索采用联合侧向热垂直加压技术充填根管以改良热连续波根充技术,通过增加根尖部的牙胶量克服该技术超充率较高,以及根尖部根管牙胶充盈率(PGFA)较低的缺点。方法:80颗离体尖牙牙根用改良双敞技术预备后,随机分为2组,分别用单纯热连续波法和侧向热垂直联合加压充填技术根充,超充样本计数;所有样本均在距根尖孔1.5mm水平截断,体视显微镜下数码拍照,计算机测定PGFA值,统计学分析。结果:实验组超充率低于对照组,差异有统计学意义(P<0.05);实验组距根尖孔1.5mm的PGFA高于对照组,差异有统计学意义(P<0.01)。结论:侧向热垂直联合加压充填技术,比单纯热连续波法具有更好的根充效果。     

Root and canal morphology of the mesiobuccal and distal roots of permanent first molars in a Kuwait population--a clinical study

Aim To identify the number of roots and canal configurations in permanent first molars of the indigenous Kuwaiti sub‐population and compare them against a similar group of non‐Kuwaiti population in different age groups and gender, and to determine the frequency of a second canal in the mesiobuccal root of maxillary first molars and distal root of mandibular first molars that could be located and treated in routine practice without using magnification or special lighting conditions. Methodology A total of 220 permanent first molar teeth of patients scheduled for root canal treatment over a period of 1 year were included. Patients were identified and grouped according to their nationality as Kuwaiti and non‐Kuwaiti (which included Filipinos, Indonesian Indians, Srilankans, Egyptians, Saudi Arabians and Syrians). In both nationality groups, patients were successively distributed into four groups based on their age. The first age group included patients below 20 years, the second 21–30 years, the third 31–40 years and the fourth were over 40 years. The first three groups comprised of 15 male and 15 female patients whilst the fourth group had 10 patients of each gender. Teeth with open apices, resorptions and calcification were excluded from the study. The teeth included were both clinically and radiographically examined for number of roots, the canal configuration and the presence of the additional mesiobuccal and distal canals and recorded. The simplified classification of canal configurations proposed by Weine was utilized. Results The incidence of a second canal in the mesiobuccal (MB) root of maxillary first molars and the distal root of mandibular first molars was not influenced significantly by nationality and gender. All the 110 maxillary first molars treated had three roots; 58% of MB root had one canal and 42% had two canals. The majority of the mesial roots had Weine type II canal configuration when the second mesiobuccal canal was present. All distobuccal and palatal roots had a single or type I canal configuration. Of the 110 mandibular first molars that were treated, 96% had two roots and 4% had three roots. When present, the third root was located either buccal or lingual to the main distal root. Overall 51% of the single distal roots had one canal whilst 49% had two canals. The mesial root frequently had a Weine type II canal configuration as did the distal root when a second canal was present. Pearson’s correlation analysis of both molars revealed a significant (P < 0.05) negative correlation (r = ?0.274, r = ?0.144) between age and number of canals as well as the type of canal. Conclusions The incidence of a second canal in distal roots of permanent mandibular first molars was 49% in the Kuwaiti population and this was similar to other Asian ethnic populations. Adopting modified access and troughing procedures revealed a 42% frequency of MB2 canals in maxillary first molars. The incidence of a second canal in both mesiobuccal roots of maxillary molars and distal roots of mandibular molars decreased significantly with age; no differences were noticed amongst the nationalities and gender studied. The possibility of extra roots should be anticipated in mandibular molars.     

人下颌恒切牙管间峡区解剖的显微CT研究

目的研究人离体下颌恒切牙管间峡区的解剖学特点。方法选择离体下颌恒切牙拍摄近远中向X线片,选出双根管牙33颗,对距根尖6 mm以内的牙根组织进行显微CT扫描。扫描层厚20 μm,每颗牙齿获得扫描截面300个。通过三维重建观察牙根管间峡区的解剖形态。记录距根尖1、2、3、4、5、6 mm处各截面根管数目及管间峡区的出现情况,并测量根管壁的最小厚度。结果所有双根管下颌恒切牙都存在管间峡区,完全峡区占49.7%,部分峡区占4.5%。距根尖6 mm内各截面管间峡区的出现率为10.0%~85.5%,卡方检验显示距根尖1~6 mm处管间峡区出现率的差异有统计学意义（P=0.001）。距根尖3~6 mm处管间峡区出现率较高,以5 mm处最高,为85.5%。距根尖6 mm以内的根管壁最小厚度均小于0.5 mm。结论下颌恒切牙管间峡区的出现率较高,根管壁最小厚度位于峡部,在临床进行根管治疗和牙髓外科手术时应引起重视。     

弯曲根管不同预备方法对其根管充填密封性的影响

目的 研究临床常用预备方法预备弯曲根管对其根管充填密封性的影响.方法 选取不同弯曲程度的离体单根管牙齿90颗,分别使用不锈钢K锉,机用ProTaper,Hero642进行根管预备.AH-PLUS根充糊剂加牙胶尖冷侧压法充填,染料浸泡,分光光度法定量分析微渗漏.结果 不锈钢K锉组预备出的根管,充填后根尖孔微渗量最大,显著大于其余两种镍钛器械预备出的根管(P＜0.05).不同根管弯曲程度对根管充填后根尖孔产生微渗漏的影响程度不同,随着根管弯曲程度增加,发生根尖孔染料微渗量增加(P＜0.05);不锈钢K锉预备的Ⅲ°弯曲根管充填后出现的根管微渗量最大.结论 当使用冷侧压法充填根管,镍钛器械预备的根管相比不锈钢预备的根管更有利于根管充填后根尖孔的密封,尤其对于弯曲根管.     

Quality of preparation of oval distal root canals in mandibular molars using nickel-titanium instruments

AIM: The aim of this study was to compare the preparation of oval distal root canals in mandibular molars using three different nickel-titanium (NiTi) instruments: Lightspeed (Lightspeed Inc., San Antonio, TX, USA). ProFile .04 (Maillefer Ballaigues. Switzerland) and Quantec SC (Tycom, Irvine, CA, USA). METHODOLOGY: Three groups of 20 extracted mandibular molars with oval distal root canals were embedded in a muffle system as described by Bramante et al. (1987) and modified by Hülsmann et al. (1999). Preparation of the root canals was performed with particular emphasis on the buccal and lingual extensions of the oval shape. The following parameters were evaluated: comparison of pre- and postoperative photographs with regard to the buccal and lingual extensions of the preparation, safety issues (file fractures, perforations, apical blockages, loss of working length), cleaning ability (SEM investigated using a 5-score system for remaining debris and smear layer) and working time. RESULTS: Superimposition of pre- and postoperative cross-sections in the majority of specimens revealed uninstrumented or incompletely instrumented buccal or lingual extensions (Lightspeed and Quantec SC, 56.7%; ProFile .04, 55%) For debris removal, Quantec SC achieved the best results (54.2% scores 1 and 2), followed by ProFile .04 (52.5%) and Lightspeed (46.7%). Preparation resulted in substantial smear layer covering the canal walls for every system (ProFile .04, 38.3%; Quantec SC, 36.6%; Lightspeed, 28.3%). Differences between the three systems were not significant for any of the parameters investigated. Preparation with Lightspeed resulted in two fractured instruments; with Quantec SC. two apical blockages occurred. With ProFile .04, no complications were noticed. Mean working time was shorter for ProFile .04 (261.2 s) than for Quantec SC (272.4 s) and Lightspeed (338.9 s); the differences were not significant. CONCLUSIONS: The flexibility of the NiTi instruments investigated in this study did not allow controlled preparation of the buccal and lingual extensions of oval root canals. The instruments frequently produced a circular bulge in the canal whilst the buccal and lingual extensions remained unprepared, leaving smear layer and debris.     

The antimicrobial effect of calcium hydroxide in root canals pretreated with 5% iodine potassium iodide

Abstract— Calcium hydroxide (CH) is often used as a routine interappointment dressing during the endodontic treatment of teeth with apical periodontitis. However, it fails to consistently produce sterile root canals. The present study was set up to find out whether an antimicrobial strategy including the use of CH could be made more effective if: 1) canals were pretreated with 5% iodine potassium iodide (IPI), and 2) the dressing period was extended up to 2 months. Fifty human teeth, with radiographically verified apical periodontitis, were microbiologically sampled. After chemomechanical preparation the canals were pretreated with IPI for 3–7 days. Teeth where microorganisms persisted were then treated with CH for 2 months. Following instrumentation and dressing with IPI, 43 bacterial strains were recovered in 22 of the teeth. Samples obtained after the CH dressing period disclosed growth of 13 facultative and two strict anaerobic strains in 10 teeth. Enterococcus faecalis was identified in two specimens. In conclusion, the present study gave no evidence for an increased antimicrobial effect of CH if it was left for longer periods in the root canal. Although pretreatment with IPI from a quantitative point of view did not seem to add antimicrobial power, it might reduce the frequency of persisting strains of E. faecalis .     

颏管的应用解剖学研究

目的 :研究国人颏管的形态及颏管与下颌管、切牙神经管的位置关系 ,为口腔牙种植等颏区手术提供解剖学数据。方法 :磨开 13例 ( 2 6侧 )甲醛溶液固定的湿下颌骨标本的下颌管前段、颏管和切牙神经管始段 ,直接观察测量。另取 2 1侧经过脱钙处理的下颌骨标本 ,解剖并显露下颌管、颏管和切牙神经管进行观测。结果 :下颌管前端分成 2个管 :颏管和切牙神经管。大多数颏管行向后上外开口于颏孔 ,颏管长为 :( 5 .61±1.0 7)mm ,管径为 :( 2 .5 3± 0 .47)mm ,颏孔前缘至下颌管前端的水平距离为 :( 2 .82± 1.2 9)mm ,颏孔下缘到下颌管上缘的垂直距离为 ( 3 .83± 1.43 )mm ,颏管与下颌管之间的角度为 ( 63 .5 7± 13 .71)° ,颏管内有颏神经和颏血管行走。结论 :下颌管向后上外方续为颏管再通向颏孔 ,并非以往认为的下颌管自后上内向前下外方向直接开口于颏孔。     

The clinical treatment of complicated root canal therapy with the aid of a dental operating microscope

Objectives: To evaluate the clinical application of the dental operating microscope (DOM) in the management of complicated root canal therapy. Methods: 345 teeth with 546 root canals which could not be successfully managed by conventional methods received therapy under the DOM with ultrasonic instruments by the same endodontists. The aetiology of the canals included calcification, broken instrument, missed canal and canal perforation. The teeth and canals successfully managed were then calculated. Results: 406 canals were successfully managed with a rate of 74.4%; 246 teeth were successfully managed with a rate of 71.3%. The rates in each category of the complicated root canals were: 74.0% for calcified canals, 72.3% for canals blocked by broken instruments, 82.5% for missed canals and 72.7% for canal perforations. Conclusions: The clinical application of the DOM is an effective way of managing complicated root canal therapy.     

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在美国牙髓病学专家Gutmann<牙髓病学解难>一书的开卷语中,引用了1884年一位英国牙髓病研究者的话:治疗前花一小会儿时间思考一下根尖病的病因,使我们理解欲达到成功目的所必须做的事;倘若病变来自感染牙髓的分解,那么将其清除,即可将多数病例治愈.     

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目的探讨前牙钙化根管治疗的可行性。方法2003年1月至2005年12月,对郑州市中医院口腔科收集的前牙钙化根管患者22例,通过寻找根管口,行根管治疗术,进行术前、术后X线片观察研究。结果20例患者顺利完成根管治疗术,2例因根管完全钙化行根尖手术。结论前牙钙化根管的治疗关键在于根管口的寻找,并进行常规根管治疗术,避免根尖手术或牙拔除术。     

钙化根管的根管显微镜治疗

目的:探讨应用根管显微镜治疗钙化根管的方法,并对其疗效进行评价.方法:因根管钙化进行根管治疗的患牙33个,在根管显微镜引导下,将超声预备、手动NiTi器械预备以及EDTA化学预备相结合进行治疗,记录预备时间,术后1周进行根管充填,半年后复查并进行疗效评价.结果:根管显微镜下钙化根管的治疗成功率为88.9%,平均每根根管耗时25.8 min.结论:在根管显微镜引导下,将超声预备、手动NiTi器械预备以及EDTA化学预备相结合可提高钙化根管治疗的成功率.