上颌磨牙近中颊根第二根管的检出率

目的 探讨上颌磨牙近中颊根第二根管(MB2)的临床检出率以及手术显微镜在提高上颌磨牙临床检出率中的作用.方法 选取进行常规根管治疗的63颗上颌第一磨牙.27颗上颌第二磨牙,以及进行显微根管治疗的55颗上颌第一磨牙,20颗上颌第二磨牙,2颗上颌第三磨牙,分别拍摄术前X线片,探查根管,记录根管数目.结果 进行常规根管治疗的上颌第一磨牙和上颌第二磨牙,MB2检出率分别为28.6%和3.7%;进行显微根管治疗的上颌第一磨牙和上颌第二磨牙,MB2检出率分别是61.8%和25%:对上颌第一磨牙常规根管治疗和显微根管治疗的MB2临床检出率进行卡方检验,X2=13.17,差异有统计学意义(P<0.001);对上颌第二磨牙常规根管治疗和显微根管治疗的MB2临床检出率进行Fisher确切概率值检测,单侧比较值为0.043,差异有统计学意义(P<0.05).结论 手术显微镜有助于提高上颌磨牙MB2的临床检出率,选择显微根管治疗有助于提升上颌磨牙根管治疗的成功率.     

上颌第一磨牙近中颊根的解剖形态研究

目的：研究上颌第一磨牙（16、26）近中颊根的解剖形态，为临床治疗提供参考。方法：使用透明标本法，将132个离体16、26制成透明牙，观察其近中颊根的牙根外形与根管形态，比较并分析两者间的关系。结果：16、26近中颊根的牙根外形按照融合角度和分叉情况的不同分为4型：Ⅰ～Ⅳ型牙根的百分比依次为40.91％、23．48％、23．48%和12．12％。根管形态按Weine法分为4型：1-1型、2—1型、1—2型、2—2型，发生率依次为32．58％、17．42％、12．12％和37．88％。并对根管的锥度和弯曲角度进行了探讨。结论：16、26近中颊根的牙根外形与根管形态间有着密切的关系，掌握其形态学规律具有重要的临床意义。     

上颌第一磨牙近中颊侧第二根管的诊断及治疗

目的探讨上颌第一磨牙近中颊侧第二根管的临床发现及治疗效果。方法选择有近中颊侧第二根管的上颌第一磨牙根尖周炎、牙髓炎患者共20例，通过X线片及临床经验寻找并确诊近中颊侧第二根管。采用常规逐步后退法预备根管，侧方加压充填根管。结果20颗患牙经完善的根管治疗后6、12个月复诊，患者无主观症状，咀嚼功能良好，X线检查原有根尖阴影明显缩小，或未见新的根尖病变发生，临床疗效均为成功。结论术前、术中、术后的X线片对上颌第一磨牙近中颊侧第二根管的诊断及治疗有较大帮助。     

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。     

上颌第一磨牙遗漏近颊第二根管的显微根管再治疗

目的：探讨运用根管显微镜对经治的上颌第一磨牙遗漏近颊第二根管（MB2）的诊治方法。方法：选择需行根管再治疗的上颌第一磨牙64个。依据x线片特征,牙冠与髓底的形态特点判断是否存在MB2。采用斜方形开髓入口,小号K锉探查,必要时使用根管手术显微镜定位MB2根管。镍钛机用根管锉冠向下法预备根管,1％NaOCL冲洗根管系统,冷牙胶侧方加压与热牙胶垂直加压充填根管。记录近颊根根管分型、根管预备过程中并发症的情况,评价疗效。结果：再治疗中共发现MB2根管55个（85．81％）,疏通45个（80％）。近颊根双根管以2—1型、2—2型较常见（76．56％）。治疗过程中未发生器械折断、管壁侧穿等并发症,治疗成功率为95．55％。结论：上颌第一磨牙MB2发生率高,通常狭窄、弯曲、隐蔽,是临床治疗的难点;临床医生有意识地寻找和在显微镜下的可视化操作能提高MB2根管的发现率和治疗的成功率。     

上颌磨牙近中颊根第二根管定位与扩通的研究

上颌磨牙常因近中颊根第二根管(the second mesiobuccal canal,MB2)的遗漏而导致上颌磨牙根管治疗失败.因而如何通过有效辅助手段发现、定位及扩通MB2成为临床医师所关注的问题.本文就上颌磨牙MB2的研究现状及根管显微镜在定位与扩通上颌磨牙MB2中的辅助作用作一综述.     

锥体束CT对上颌第一磨牙近中颊根管形态的研究

目的：通过锥体束CT（cone--beam computed tomography,CBCT）成像系统分析上颌第一磨牙近中颊根根管形态及第二（second mesiobuccal,MB2）根管的发生率。方法：选择95名进行CBCT扫描的患者,共计180颗上颌第一磨牙,观察近颊根根管形态、MB2根管的发生率、左右侧发生比率及男女发生比率差异。结果：上颌第一磨牙近颊根管形态以Ⅲ型为主,MB2根管发生率为79．4％,左右侧发生比率无统计学差异（P=0．846）,男性发生率明显高于女性（P=0．043）。结论：上颌第一磨牙近颊根MB2根管的发生率较高,可通过CBCT有效的发现MB2根管,为临床诊疗提供依据。     

上颌第一磨牙近中颊根第二根管肉眼发现率的临床研究

选择临床209例上颌第一磨牙,采用改良髓腔入路探查并治疗近中颊根第二根管(MB2),研究其临床发现率和影响因素。结果显示209例上颌第一磨牙MB2临床肉眼发现率为45.9%,年龄及再治疗对其发现率有显著影响。MB2在上颌第一磨牙中具有较高发生率,年轻患者及未经治疗病例在临床肉眼操作下更易发现MB2根管口。     

上颌第二磨牙近中颊根第二根管的解剖定位

目的:观察髓室底的解剖形态和根管口的数目和位置,探寻近颊根第二根管(MB2)根管口的定位规律.方法:选择 (7|7)离体牙220 颗,利用耳鼻喉科内窥镜系统对髓室底进行观察,测量髓室底根管口之间的位置关系,统计MB2出现率,探寻MB2根管口定位规律. 结果:髓室底观察发现,MB2基本上发生在MB-P连线的近中舌侧,MB2的发生率为38.2%. MB2-MB的距离为(1.56±0.65) mm.MB-DB的距离为(2.34±0.78) mm, MB-P的距离为(5.05±1.26) mm.∠MB2-MB-P的角度为(22.21±10.35)°. 结论:MB2根管口多位于MB-P连线的近中舌侧,且在以MB为中心, MB-P为一边,向近中做角度为(22.21±10.35)°的扇形范围内基本上能找到MB2.     

上颌第一磨牙根管口形态、位置的应用解剖

目的 研究上颌第一磨牙根管口形态和位置关系，为根管治疗时寻找根管口提供解剖学依据。方法 采用目镜配置测微尺的XTL－2型体视摄影显微镜，观测42个上颌第一磨牙的根管口形态及其与髓室底截面形态和髓室底沟的位置关系。结果 ①上颌第一磨牙根管口可呈长条形、卵圆形、圆形、哑铃形和肾形；80．95％含3个根管口，其远颊根管口孔径最小。②近颊根舌侧根管口的出现率为14．29％。③骶室底截面呈长方形和圆三角形的占76．19％。结论 ①寻找根管口可综合髓室壁夹角、根管口间距及髓室底沟的走各进行；②上颌第一磨牙的第四根管口的出现率约为15％。     

Root canal morphology of maxillary permanent first molar teeth at various ages

The root canal anatomy and pulp chamber morphology of 216 maxillary permanent first molar teeth of known age was examined using a radiographic technique after infusion of the root canal system with a radiopaque sodium iothalontate gel. This technique proved to be a rapid and effective method for the examination of root canal morphology and is recommended when root canal anatomy needs to be examined before further investigations are carried out. Over 95% of palatal and disto-buccal roots contained a single root canal. The mesio-buccal root was more complex. All types of configurations were seen. Only 26% of mesio-buccal roots showed a single canal. The pulp canal in all roots appeared to narrow at an early age. In the mesio-buccal root, a definite two-directional calcification pattern was apparent in most teeth by the age of 10. The rate of progress of root formation was very variable. There was no apparent relationship between the type of canal system in the mesio-buccal root and the type of canal orifice present. The transverse cross-sectional shape of the pulp chamber was trapezoidal in 81% of teeth.     

不同方法探查上颌第一恒磨牙根管口的研究

目的 :比较临床上不同探查方法探查根管口的效率。方法 :采用肉眼观察 (上颌位 )、肉眼观察 (直视位 )、放大镜观察、# 15K型锉探查、牙科手术显微镜观察研究 80个离体上颌第一恒磨牙的髓腔系统。结果 :上颌第一恒磨牙近颊根有较高的多根管口率 ,五种方法多根管口的发现率分别为 :30 %、30 %、30 %、5 1.2 % ,6 6 .2 % ,K型锉和牙科手术显微镜多根管发现率与前三种方法比较差异有统计学意义 (P <0 .0 5 ) ,K型锉与牙科手术显微镜多根管发现率差异无统计学意义 (P >0 .0 5 )。手术显微镜还发现远颊根双根管口率为3.75 %。结论 :上颌第一恒磨牙根管系统复杂。临床使用小号K型锉能发现绝大部分根管口 ,而使用牙科手术显微镜对于完善的根管治疗术是有益的。     

Determination of canal orifice co-ordinates and MB2 incidence of maxillary first molars in a Turkish sub-population

Objectives. To measure the co-ordinates of the root canal orifices and to determine the incidence of mesiobuccal-2 (MB2) in maxillary first molars in a Turkish sub-population. Materials and methods. Standard digital photographs were taken under a stereomicroscope from the occlusal aspect of each tooth (n = 176) before and after crown removal. Canal orifices were negotiated under moderate magnification using dental loupes. The coordinates of the orifices and the distances of each from the central fossa were measured by using geographic software. Intensity maps of the orifice locations were created by using the co-ordinates of all canal orifices. A representative map was drawn using the mean values of orifice locations and access projection area. Results. In the right maxillary first molars, the mean values for the (X, Y) co-ordinates were (0.67, 2.68) for mesiobuccal-1 (MB1), (0.81, 0.84) for MB2, (?1.12, 1.26) for distobuccal-1 (D1), (?0.89, 0.23) for distobuccal-2 (D2) and (0, ?2.50) for palatinal (P); the corresponding mean values in the left maxillary first molars were (?0.78, 2.56), (?0.98, 0.90), (0.99, 1.18), (0.69, 0.78) and (0.00, ?2.53), respectively. The average MB1–MB2 distance was 1.97 mm. Distobuccalcanal orifices were localized at the distal side of the center in 98.3% of teeth. The incidence of MB2 was 46.02%. Conclusions. The distobuccal canal orifice is mostly located on the distal side of the central fossa. Thus, it should be considered that the access cavity of the maxillary molars may not be always limited mesially. The incidence of MB2 in this sub-population was 46.02%, which is of great importance clinically.     

手术显微镜对上颌第一恒磨牙近舌根管寻找定位的临床评价

目的 :评价手术显微镜在上颌第一恒磨牙近中颊根的近舌根管 (MB2根管 )定位中的作用。方法 :选取上颌第一恒磨牙牙髓病或尖周病患牙 52个 ,采用肉眼观察或手术显微镜下观察来寻找、定位上颌第一恒磨牙MB2根管口 ,运用统计学分析将两者对MB2根管的发现率进行比较。结果 :肉眼观察组 30例中有1 5例发现MB2根管。手术显微镜组 2 2例中有 1 7例发现MB2根管 ,手术显微镜组对MB2根管的发现率显著高于肉眼组 (P <0 .0 5)。结论 :手术显微镜的应用有助于寻找、发现MB2根管 ,从而有效改善上颌第一恒磨牙根管治疗的成功率     

上颌第一磨牙远颊双根管1例

上颌第一磨牙根管系统复杂多变,远颊双根管发生率十分低。本文报道了一例上颌第一磨牙远颊双根管行根管治疗病例,并针对上颌第一磨牙根管系统特征、遗漏根管发生特点以及如何提高根管查全率作出总结。     

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。     

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.     

Second mesiobuccal canal detection in maxillary first molars using microscopy and ultrasonics

The aim of this study was to investigate whether the use of operating microscope in combination with ultrasonics increased the rate of second mesiobuccal (MB2) canal detection in permanent maxillary first molar teeth. A hundred extracted human maxillary first molars were assessed. After location of the main canals, the MB2 canal was sought in all teeth first without microscopy, then with the aid of the operating microscope and finally with the combined use of the operating microscope and ultrasonics. With these techniques, the MB2 canal was detected in 62%, 67% and 74% of the teeth, respectively. The combination of the operating microscope and ultrasonics detected significantly more MB2 canals than when no microscopy was utilized (P < 0.05). Sectioning of the roots disclosed the presence of the MB2 canal in 82% of the teeth. Twenty‐nine per cent of the teeth had a separate MB2 canal orifice and separate apical foramina. The results of this study suggested that the combined use of the operating microscope and ultrasonics increased the detection of MB2 canals in maxillary first permanent molars.     

上颌第一磨牙根管系统的研究

目的 观察上颌第一磨牙的根管系统。方法 制备50个上颌第一磨牙透明牙标本,显露根管系统的空间构型,在体视显微镜下观察并记录根管系统的形态,结合应用加以统计。结果 ①上颌第一磨牙近中颊根单根管率为66%,其中Ⅰ型占38%,双根管率为34%,远中颊根Ⅰ型占74%,腭根Ⅰ型占94%。②根管侧支、根尖分歧、根尖分叉多见于近颊根,在近颊根的发生率为40%, 远颊根的发生率为24%,腭根的发生率为6%,发生部位多见于根尖1/3。结论 上颌第一磨牙近颊根的根管系统最为复杂,根管变异较远颊根多,腭根变异最少。