下颌第二磨牙根管系统的临床诊断和治疗

目的:探讨下颌第二磨牙根管系统的特征及临床诊断和治疗方法。方法:选取患牙髓炎或根尖周炎的下颌第二磨牙 127个,拍摄术前X线片,探查根管,确定根管形态和类型;采用机用镍钛器械Hero642预备根管,热牙胶垂直加压技术充填根管。根据治疗前后的X线片评价根管预备和充填效果。结果:下颌第二磨牙独立 3个根管的发生率为 54. 3%, 独立 2个根管和单一根管的发生率为 11. 0%和 3. 1%,C形根管的发生率为 31. 5%,以Ⅰ、Ⅱ型居多。所有患牙均无根管内并发症发生,治疗效果佳。结论:下颌第二磨牙根管系统以独立的 3个根管为主,其次为C形根管,根管探查结合X线片可诊断C形根管;机用镍钛器械预备根管热牙胶垂直加压技术充填根管可获得良好的治疗效果。     

下颌第二磨牙C形根管的临床诊断和治疗

目的：探讨下颌第二磨牙C形根管的临床诊断和治疗。方法：选择需进行治疗的下颌第二磨牙104个,通过术前拍摄X线片和术中根管显微镜下髓腔探查,按照AL-Fouzan术前X线诊断标准和Melton分类标准分别诊断是否为C形根管。采用手用Protaper进行根管预备,热牙胶垂直加压技术充填根管。记录C形根管口的类型,统计两种方法诊断的成功率。根据治疗前、中、后的X线评价根管预备和充填的效果,3～6个月后复查。结果：下颌第二磨牙C形根管术前X线片和根管显微镜的诊断率分别为72.1%和90.7%,所有患牙均无根管内并发症发生,治疗效果好。结论：术前X线片和根管显微镜相结合大大提高了下颌第二磨牙C形根的诊断率,镍钛器械预备根管和热牙胶垂直加压技术充填根管可获得良好的治疗效果。     

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。     

声波器械辅助镍钛根管器械预备老年人下颌第二磨牙C形根管的观察

目的：观察声波器械辅助镍钛根管器械预备老年人下颌第二磨牙C形根管的临床效果。方法：对133例老年人的140颗具有C形根管,诊断为慢性根尖周炎的下颌第二磨牙,随机分为二组：实验组,68颗,采用MM1500声波手机及其配套的Rispisonic锉针辅助镍钛旋转器械Hero642系统预备根管,对照组,72颗,镍钛旋转器械Hero642系统预备根管。两组均用氢氧化钙糊剂根管封药消毒后侧方加压法完成根管充填。对二组的根管预备并发症、根管治疗期间疼痛反应、根管充填质量进行比较。结果：实验组较对照组的疼痛反应轻且少,根管充填质量好于对照组,对照组根管预备并发症的总数相对较多。结论：声波器械辅助镍钛根管器械预备老年人慢性根尖周炎的下颌第二磨牙C形根管,可减轻减少疼痛反应,减少预备并发症,提高根管充填质量,具有临床应用价值。     

下颌切牙双根管的显微根管治疗

目的评价显微根管治疗术处理下颌切牙双根管的临床疗效。方法选取143颗需进行根管治疗的下颌切牙（下颌中切牙68颗,下颌侧切牙75颗）,拍摄术前X线正位投照片和偏位投照片。对单根管患牙采用常规根管治疗;对疑为双根管的患牙先常规探查根管,再在牙科手术显微镜下探查并疏通根管,机用镍钛器械预备根管,垂直加压充填技术充填根管。记录根管类型,不同X线投照角度、使用和未使用牙科手术显微镜时多根管的发现率,根据术前、术中及术后X线片评价根管预备和充填效果。结果采用显微根管治疗,下颌中切牙、侧切牙双根管的发现率分别为26.47%、29.33%,X线偏位投照片双根管的发现率高于正位投照片;使用牙科手术显微镜后,多根管的发现率高于未使用时;在牙科手术显微镜下进行根管预备,无根管堵塞、偏移、台阶、器械分离等并发症发生;134颗患牙适充,9颗有糊剂或牙胶超充,无欠充。结论显微根管治疗是处理双根管下颌切牙的有效方法,在牙科手术显微镜下以机用镍钛器械预备根管,垂直加压充填技术充填根管可取得良好的治疗效果。     

下颌前磨牙C形根管的诊断和治疗

目的：探讨下颌前磨牙C形根管的发现率及其诊治方法。方法：选取需要根管治疗的下颌前磨牙300个,拍摄术前正位和偏位X线牙片。多根管牙插诊断丝摄片。结合C形根管的诊断标准,诊断为C形根管的忠牙,记录髓室底形态和X线影像类型。所有患牙使用镍钛机动根管器械预备,侧方加压法充填根管。根据术前、术中和术后x线片评价根管预备和充填效果。结果：第一和第二前磨牙C形根管的发现率依次为5．56％和2．50％。髓室底以C2型多见,X线影像以尖部融合型多见。治疗中无根管堵塞等并发症的发生。根管充填效果,13例C形根管中有5例超充,8例恰充。结论：髓腔探察和插诊断丝拍片是诊断下颌前磨牙C形根管的有效方法。     

下颌第二磨牙C形根管预备方法的临床探讨

目的 探索预备下颌第二磨牙C形根管的有效方法.方法 对下颌第二磨牙C形根管初诊或根管再治疗的患牙,采用"拉网法"进行根管预备,完成根管充填后拍X线片检查充填效果.结果 C形根管的峡区被充分预备和成形,根充后峡区有均匀稀薄的X线阻射影像.结论 该根管预备方法能有效地预备C形根管的峡区,且不易发生根管侧穿.     

下颌第一磨牙近中根管的根管口分型和临床疗效分析

目的探讨下颌第一磨牙近中根管的根管口形态特点和临床治疗方法。方法选取71颗临床进行根管治疗的下颌第一磨牙．在手术显微镜下观察并记录近中根管的根管口形态．分类计数;采用Protaper机用镍钛器械及超声器械进行根管预备,常规针式冲洗合并超声荡洗．热牙胶垂直加压充填技术充填根管;根据治疗前后临床检查及x线片评价根管预备和充填的效果。结果所有样本中单根管口出现率为2．82％（2例）、双根管口为91．55％（65例）、三根管口为5．63％（4例）。其中双根管口之间有峡区的为38例（53．52％）、无峡区的为27例（38．03％）。所有患牙根管治疗后均无根管内并发症发生．术后1年根管治疗成功率为92．9％。结论下颌第一磨牙根管形态复杂,手术显微镜有助于根管形态的探查．机用镍钛器械合并超声技术预备根管．超声冲洗和热牙胶垂直加压技术充填根管可获得良好的治疗效果。     

上颌第一磨牙近颊第二根管的临床治疗

目的 探讨上颌第一磨牙近烦第二根管（second mesiobuccal canal，MB2）的特征及临床治疗方法。方法 选取患牙髓炎或根尖用炎的上颌第一磨牙95颗，拍摄术前X线片，术中采用小号K锉配合15％EDTA溶液探查根管，记录根管数目、形态和类型；采用机动镍钛器械Hero642进行根管预备，侧向加压充填技术充填根管。结果上颌第一磨牙MB2的发现率为81．1％，扩通的MB2占72．6％，多数MB2根管细小弯曲，需用小号锉配合使用EDTA进行疏通，机动镍钛器械预备根管无明显并发症。结论上颌第一磨牙MB2的发生率高，多数根管细小弯曲，小号K锉配合EDTA疏通根管，机动镍钛器械预备可获得良好的治疗效果。     

根管显微镜下下颌磨牙C形根管的临床分型与治疗

目的:探讨显微根管治疗技术对下颌磨牙C形根管系统的临床诊治疗效.方法:选择临床上需行根管治疗术且为C形根管的下颌磨牙79例,机用镍钛根管锉冠向下法预备主根管,显微镜下使用超声与K锉双敞法预备峡区,热牙胶垂直加压充填根管.记录根管分型、根管预备过程中并发症的情况,通过临床症状和体征、术前后X线片,半年随访X线片评价疗效.结果:C形根管系统中C1型较少见(12.66%);C2型发生率较高(62.02%),C2、C3型的近舌根管易超填(超填发生率:C2型4.08%;C3型15%).治疗过程中未发生器械折断、管壁侧穿等并发症,半年回访率为72.15%,随访病例中治疗成功率为91.3%.结论:C1、C2型具有较大的弧形带状根管,是临床治疗的难点;显微根管治疗术可以获得理想的疗效,值得临床推广使用.     

Root and canal morphology of permanent mandibular molars in a Sudanese population

AIM: To investigate variations in the root canal systems of first and second permanent mandibular molar teeth in a Sudanese population using a clearing technique. METHODOLOGY: Two hundred extracted first and second permanent mandibular molars from three cities in the state of Khartoum were studied. Access cavities were prepared and pulp tissue was removed by immersion in 5% sodium hypochlorite under ultrasonication; Indian ink was then injected into the root canal systems assisted by a vacuum applied apically. The teeth were rendered clear by demineralization and immersion in methyl salicylate before evaluation. The following observations were made (i) number of roots and their morphology; (ii) number of root canals per tooth; (iii) number of root canals per root and (iv) root canal configuration. RESULTS: Overall 59% of mandibular first molars had four canals with 3% having a third distolingual root. Seventy-eight per cent of second mandibular molars had two separate flat roots, whilst 10% were C-shaped. The most common canal system configurations were type IV (73%) and type II (14%). Inter-canal communications were more common in the mesial roots. The prevalence of inter-canal communications was 65% in first molars and 49% in second molars. CONCLUSIONS: In this sample of Sudanese teeth, 59% of the mandibular first permanent molars had four root canals whilst 10% of the mandibular second molars had C-shaped roots/canals.     

Root and canal morphology of Thai mandibular molars

AIM: To investigate the root and canal morphology of 351 mandibular permanent molars collected from an indigenous Thai population. METHODOLOGY: The cleaned teeth were accessed, the pulp dissolved by sodium hypochlorite under ultrasonication and the pulp system injected with Indian ink. The teeth were rendered clear by demineralization and immersion in methyl salicylate. The following observations were made: (i) number of roots and their morphology; (ii) number of root canals per tooth; (iii) number of root canals per root; (iv) root canal configuration in each root using Vertucci's classification, with additional modifications; and (v) presence and location of lateral canals and intercanal communications. RESULTS: Of 118 mandibular first molars, 13% had a third disto-lingual root. In three-rooted teeth, 80% of the main distal roots and 100% of the disto-lingual roots had type 1 canal systems. Of 60 mandibular second molars, 10% had C-shaped roots, the majority of which had type 1 (33%) or type IV (33%) canal systems. Of 173 third molars, 68% had two separate roots, 20% had fused roots and 11% had a single C-shaped root; the majority had two canals (61%). CONCLUSIONS: This study suggests that Thai molars exhibit features of both Caucasian and Chinese teeth.     

Root and canal morphology of mandibular first and second molar teeth in a Jordanian population

Aim  To examine the root and canal morphology of mandibular permanent first and second molar teeth in a Jordanian population.
Methodology  A total of 685 extracted mandibular first and second permanent molar teeth were collected from dental clinics within north Jordan. The teeth were examined visually and the root number and morphology were recorded. After that, access cavities were prepared, pulp tissue dissolved by sodium hypochlorite and the root canals injected with Indian ink. Stained teeth were decalcified with 10% nitric acid, dehydrated with ascending concentrations of alcohol and rendered clear by immersion in methyl salicylate. The following observations were evaluated: (i) number of canals per root; (ii) number of root canals per tooth; (iii) canal configuration in each root; (iv) number and location of lateral canals and (v) presence of intercanal communications.
Results  Of 330 mandibular first molars, the majority had three (48%) or four (46%) canals, whilst 4% had a third disto-lingual root. Of 355 mandibular second molars, 58% had three canals, 19% two and 17% had four canals, whilst 10% had C-shaped roots. The most prevalent canal configuration in the mesial root of both first (53%) and second (40%) molars was type IV, and in distal roots was type I (54% in first and 79% in second molars).
Conclusions  Jordanian mandibular first and second molar teeth exhibit features close to the average Caucasian root and canal morphology.     

Root and canal morphology of Burmese mandibular molars

AIM: To study the root canal morphology of Burmese mandibular molars using a canal staining and tooth clearing technique. METHODOLOGY: Mandibular molars (331) were collected from indigenous Burmese patients and designated; first (139), second (134), third (58) molars. Following pulp tissue removal and staining of the canal systems with Indian ink, the teeth were decalcified and rendered clear with methyl salicylate. Under magnification (x3), the following features were evaluated: (i) root number and morphology, (ii) number of canals per root, (iii) root canal configuration (Vertucci's classification), (iv) number of apical foramina per root, (v) number and location of lateral canals and (vi) the presence of intercanal communications. RESULTS: Most of the mandibular molars had two separate roots (90% in first molars, 58% in second molars, 53% in third molars) and three-rooted teeth were (10%) confined to first molars. C-shaped roots occurred in 22.4% of mandibular second molars and a further 14.9% had two fused roots. The majority (81-100%) of conical distal roots possessed a simple type I (single canal) configuration. Whilst the canal system of mesial roots was more complex: 52-85% contained two canals, of which type II (two orifices, one foramen) and type IV (two separate canals) were the most prevalent. A broad range of 6.5-70% had intercanal communications. Fused/single-rooted molars had a wide variety of canal system types but intercanal communications were rare except in C-shaped roots (33%) of second molars. The majority of roots of all molars contained one or two apical foramina (91-96%) and the apical third had the highest prevalence of lateral canals. CONCLUSIONS: There was a high prevalence of three-rooted mandibular first molars and C-shaped roots/canals in mandibular second molars from a Burmese population. Conical roots tend to have simple canal systems, whilst flatter/broader roots have more complex canal systems.     

Root and canal morphology of permanent mandibular molars in a Sri Lankan population

The main purpose of this study was to investigate the root and canal morphology of Sri Lankan mandibular molars and to determine the affinities of these morphological variations to those of people of European and Asian origin. Two hundred mandibular first and second molars were examined. The number of roots and the prevalence of C-shaped (gutter-shaped) roots in mandibular second molars were recorded. Root canal morphology was studied using a clearing technique. The examination of root canal systems of the teeth was based on Vertucci's classification. Among mandibular first molars, only 3% had three roots. Mesial roots of the first molar typically presented with two canals and two apical foramina with type IV, V, or VI canal configuration. Most distal roots of the first molar presented with a type I canal configuration. The remainder were distributed mainly between types III and V. Among mandibular second molars, 6% had single C-shaped roots, while C-shaped canals were found in only 2%. The majority of mesial roots of the second molar showed one or two canals, with one apical foramen with type I, II, or III canal morphology. In addition, the distal root commonly showed type I canal configuration. Intercanal communications and lateral canals were more frequently seen in the first molar than in the second. The root canal morphology in mandibular molars varies among population groups. Mandibular root and canal morphology of Sri Lankan people has closer affinities with that of people of European than of East Asian origin.     

下颌第二磨牙扇形根管的出现率与牙根形态的关系

目的：调查下颌第二磨牙扇形根管的出现率与牙根形态的关系。方法：通过进行根管治疗的202个下颌第二磨牙的临床检查，对其牙根形态和根管形态分类计数，调查扇形根管的出现率。结果：分叉根的扇形根管出现率为18．7％，平行根为35．5％，锥形根为76．3％。结论：近中根与远中根相距越近，扇形根管的出现率越高。     

下颌第二恒磨牙牙根及根管形态的锥形束CT研究

目的 使用锥形束CT扫描评估下颌第二恒磨牙牙根和根管解剖形态.方法 收集354例患者双侧下颌第二恒磨牙的锥形束CT图像,统计下颌第二恒磨牙牙根数目、根管数目和构型,以及C形根管的发生率.结果 下颌第二恒磨牙以双根最多,发生率为57.34%,C形根的发生率为38.28%;双根者近中根多为2-2型(80.54%),远中根多为1-1型(96.06%);C形根管的发生率为25.99%,左、右下颌的发生率没有统计学差异(P>0.05).结论 下颌第二恒磨牙牙根和根管解剖形态复杂多样,锥形束CT能为根管治疗提供参考.     

C-shaped root canals in mandibular second molars in a Chinese population

Abstract The purpose of this investigation was to study the prevalence of C-shaped roots, root canal orifices, and root canals in the mandibular second molars of a Chinese population. A total of 581 second mandibular molars were collected in Hong Kong and Taiwan. The teeth were demineralized and placed in methyl salicylate to induce transparency. The pulp chamber floor was examined to ascertain the number of root canal orifices. Chinese ink was then injected into the root canal system to demonstrate the root canal anatomy. The mandibular second molars had separate roots in 66.4%, cone-shaped roots in 2.1% and C-shaped roots in 31.5%. The C-shaped roots had C-shaped canal orifices in 68.3% (21.5% of whole material). True C-shaped root canals were observed in 65.8% of the teeth with C-shaped orifices and in 13.9% of the whole material. Separate root canals were seen in 34.2% of the teeth with C-shaped orifices. Separate canal orifices were found in 31.7% of the C-shaped roots and 7.4% of these roots had true C-shaped canals. In the whole material 0.9% of the roots with individual canal orifices had C-shaped canals. In conclusion, C-shaped root canals were common in mandibular second molars in the Chinese subjects studied. The C-shaped root canals were often, but not always recognized because of a C-shaped canal orifice.