C形根管系统的形态、诊断和治疗

C形根管系统是根管横截面呈“C”形的根管系统,常发生于下颌第二恒磨牙。C形根管系统的横截面形态从根管口到根尖可发生明显变化。C形根管系统的术前诊断、牙髓摘除、根管预备、根管充填以及桩腔预备和修复较常规情况更为困难。手术显微镜的应用可提高C形根管系统的诊断和治疗成功率。     

C形根管系统的形态、诊断和治疗

C形根管系统是根管横截面呈“C”形的根管系统，常发生于下颌第二恒磨牙。C形根管系统的横截面形态从根管口到根尖可发生明显变化。C形根管系统的术前诊断、牙髓摘除、根管预备、根管充填以及桩腔预备和修复较常规情况更为困难。手术显徽镜的应用可提高C形根管系统的诊断和治疗成功率。     

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。     

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.     

下颌第二磨牙根管显微镜下根管口分型探讨

目的通过显微镜分析下颌第二磨牙根管口的解剖特点及分型。方法选择患牙髓炎或根尖周炎的下颌第二磨牙653个,根管显微镜下观察并记录根管口形态,对其根管口形态分类计数,计算其出现率。结果下颌第二磨牙单根牙Ⅰ-1型47例(7.20%),Ⅰ-2型65例(9.95%),Ⅰ-3型263例(40.27%),Ⅰ-4型22例(3.37%);C形根管256例(39.21%)。完全C形根管及部分C形根管分别占17.31%、21.90%。结论根管显微镜下可以更好地观察下颌第二磨牙根管口形态,提高C形根管诊断率。根管口形态呈C形根管系统较多,不利于根管的彻底清理和充填。     

锥形束CT在下颌第二磨牙C形根管治疗前中后的应用

下颌第二磨牙C形根管存在根管变异和不规则峡区,容易造成根管清理不彻底和充填不足。锥形束CT(CBCT)可清晰地显示C形根管在矢状面、冠状面和横断面的解剖形态。CBCT空间分辨率高,图像清晰;可选择合适的视野,小视野图像更清晰;可以光盘形式最大限度的保存图像信息,方便临床医生在计算机上多层面、多方位的仔细观察;金属伪影少,辐射剂量低,扫描时间短;所显示下颌第二磨牙C形根管图像的矢状面、冠状面和横断面无前后重叠、无变形和无放大等情况,可为了解下颌第二磨牙C形根管形态提供清晰的三维影像。下颌第二磨牙C形根管预备的难度主要有相对独立的根管间有大量的副根管、交通支和根管弯曲,传统器械难以进入峡区;将显微镜和CBCT共同使用,可提高下颌第二磨牙C形根管的治疗效果。在根管预备前行CBCT检查,可提醒术者避免过度切削并防止侧穿。本文就CBCT在下颌第二磨牙C形根管治疗前中后的应用等研究进展作一综述。     

锥形束CT在下颌第二磨牙C形根管系统应用的研究

目的　采用锥形束CT（简称CBCT）研究下颌第二磨牙C形根管的解剖形态,为根管治疗提供更加直观的影像学依据。方法　使用CBCT观察441例患者双侧下颌第二磨牙,统计C形根管的发生率以及根管形态。结果　C形根管的发生率为41.72%,C形根管类型变化多样,C形根管的发生率在性别、年龄间无统计学差异。结论　C形根管在下颌第二磨牙有很高的发生率,并且解剖形态有较大差异,CBCT在诊断C形根管方面具有重要作用。     

下颌第二磨牙C形根管的研究现状

C形根管系统的解剖形态多变常见于下颌第二磨牙,最主要的解剖学特征为弧形峡区连接各个根管。尽早识别C形根管的构造有助于根管系统的清理、成形和充填。C形根管形态上的变化使治疗变得困难,因此治疗前的正确诊断是有必要的。近年来,显微CT作为一种无创方式被用于C形根管横断面的研究。     

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.     

C形根磨牙根管治疗后CAD／CAM高嵌体修复的临床研究

目的观察CAD／CAM全瓷高嵌体修复根管治疗后C形根管下颌第二磨牙的临床效果。方法选择C形根管下颌第二磨牙24例,进行完善根管治疗,进行CAD／CAM全瓷高嵌体修复。术后即刻、6月／3及18月,参考美国公共健康会（USPHS）标准,对其临床效果进行观察。结果CAD／CAM全瓷高嵌体成功率高于90％。结论CAD／CAM全瓷高嵌体修复C形根管下颌第二磨牙根管治疗后效果良好,值得在临床推广。     

感染根管细菌生物膜的治疗策略

根尖周炎是发生在根尖周组织的炎症性疾病，主要由根管内的感染引起。其根管内的细菌主要以难清除的生物膜形式定植，为临床治疗带来了难题。因此，了解根管细菌生物膜的特性、掌握治疗方法对于提高感染根管治疗成功率具有重大意义。     

锥体束CT对维吾尔族成人下颌第二磨牙C形根管的研究

目的: 通过锥体束CT(cone-beam computed tomogphy,CBCT)成像系统对新疆维吾尔族成人下颌第二磨牙C形根管的发生率及其形态特征进行研究。方法: 选择来我院体检且下颌牙列完整的100名维吾尔族成人,进行CBCT扫描,观察下颌第二磨牙的根管形态。结果: C形根管的发生率为15.0%,C 形根管类型变化多样。结论: C形根管在下颌第二磨牙有较高的发生率,且解剖形态存在较大差异。CBCT在C形根管的诊断方面具有重要作用,可以为维吾尔族成人下颌第二磨牙C形根管的临床诊疗提供依据。     

C-shaped root canal in a maxillary first molar: a case report

AIM: This case report presents an unusual C-shaped root canal system in a maxillary first molar tooth. SUMMARY: Although C-shaped root canals are most frequently seen in the mandibular second molar, they may also appear in maxillary molars. A literature search revealed only a few case reports of C-shaped root canal systems in maxillary molars. The present case describes a C-shaped canal in the buccal root of a maxillary first molar. The endodontic access cavity displayed two canal orifices, one leading to the canal system in the buccal root, the other into the palatal root canal system. In the buccal root, what appeared to be the mesial and distal canals joined to form a single C-shaped canal. KEY LEARNING POINTS:--Careful examination of radiographs and the internal anatomy of teeth is essential.-- The location and morphology of root canals should be identified at high magnification under the microscope.     

Root and root canal morphology of mandibular second permanent molars in the Gansu province population: A CBCT study

To study the anatomical characteristics of the root and root canal system of the mandibular second molars in the population of Gansu province, and to provide theoretical and clinical references for improving the success rate of root canal therapy (RCT) of mandibular second molars. The number of roots and root canals, root canal type and pulp chamber height of mandibular second molars were determined by observing cone-beam computed tomography (CBCT) images of people living in Gansu. The most common type of mandibular second molars in the Gansu province population was a double root with three root canals (47.55%), followed by a C-shaped root (35.56%). There were more females than males with a C-shaped root (p < 0.05). The most common root canal subtype of the C-type root was C3 (13.91%). Most of the population (77.11%) had bilateral mandibular second molars with symmetrical root canal morphology. With an increase in age, the height of the pulp chamber decreased significantly. The incidence of root canal variation of the mandibular second molars is relatively high in the population of Gansu province. Preoperative examination with CBCT is essential for mandibular second molars that need RCT to avoid root canal treatment failure and decrease the occurrence of postoperative pain as much as possible.     

下颌第二磨牙C形根管的特点和临床治疗

目的探讨下颌第二磨牙C形根管的发生率、临床诊断和治疗方法。方法通过对152例下颌第二磨牙拍摄术前X线片和术中根管探查,按照Melton标准诊断C形根管;采用机用镍钛器械Hero642进行根管预备,次氯酸钠超声冲洗,热牙胶垂直加压技术充填根管。记录C形根管的发生率及临床特点,根据治疗前、中、后的X线片评价根管预备和充填的效果。结果下颌第二磨牙C形根管的发生率为32.2%,79.6%的C形根管患牙X线片表现为锥形融合牙根,20.4%表现为近、远中独立牙根;所有患牙均无根管内并发症发生,治疗效果好。结论下颌第二磨牙C形根管主要存在于融合牙根,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、次氯酸钠超声冲洗和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。     

口腔锥形束CT在下颌第二磨牙C形根管诊治中的应用

目的探讨口腔锥形束CT(cone-beam computed tomography,CBCT)在根管治疗中诊断治疗下颌第二磨牙C形根管的临床应用。方法选取初次根管治疗失败的下颌第二磨牙62颗,根尖片不能确定根管解剖形态以及可疑遗漏根管,患牙采用CBCT进行扫描三维重建。结果使用CBCT确定下颌第二磨牙中52颗为C形根管,C形根管发生率达83.87%,C形根管中28颗为C1型变异根管(53.84%),18颗为C2型变异根管(34.62%),6颗为C3型变异根管(11.54%)。52颗患牙除2颗因根管侧穿导致根管治疗失败外,其余50颗患牙通过热牙胶充填与垂直加压技术将软化的牙胶充入不规则的根管系统,达到严密充填根管,根管再治疗后患牙成功治疗的有50颗(96.15%),均无不适症状。CBCT在根管治疗中辅助定位变异根管,定位准确率较高。结论 CBCT影像精密度高,可从三维角度分析根管,在根管治疗中诊断治疗下颌第二磨牙C形根管具有临床指导意义。     

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.     

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。