上颌第三磨牙根管形态的CBCT研究

目的：应用锥形束CT（cone?beam computed tomography ,CBCT）技术研究上颌第三磨牙的根管形态,为临床治疗提供解剖学依据。方法随机调取397颗上颌第三磨牙的CBCT资料,分析上颌第三磨牙的牙根数目、根管数目、根管分类等。结果397颗上颌第三磨牙中,三根牙最多,占43.07%;融合根牙次之,占40.30%。分析根管数目显示,三根管最多,占47.86%;单根管次之,占28.21%。根据Vertucci根管分类,89.6%的牙根以Ⅰ型根管为主,但仍会出现根管治疗时较难操作的Ⅱ型、Ⅲ型、Ⅴ型、其他型等根管。结论上颌第三磨牙根管解剖形态多样,根管系统复杂、变异大。     

壮族人群恒前牙根管弯曲度测定

目的了解壮族人群恒前牙的根管弯曲情况。方法收集新鲜拔除的壮族人群恒前牙245颗,采用间接影像学手段观察其根管类型和弯曲形状,在Schneider法和Sch覿fer法的基础上,结合电子测量尺软件测量分析218颗Ⅰ型根管牙齿的弯曲度、弯曲半径和弯曲长度。结果壮族人群恒前牙以Ⅰ型根管为主,有13颗下颌中切牙和12颗下颌侧切牙为Ⅱ、Ⅲ、Ⅳ型根管。上颌中切牙、侧切牙、尖牙以及下颌中切牙、侧切牙、尖牙Ⅰ型根管近远中向弯曲发生率分别为40%、80%、77%、65%、66%、73%,唇舌（腭）向弯曲发生率分别为62%、69%、70%、62%、41%、61%。弯曲部位多在根尖1/3,多为中度弯曲;上颌尖牙在近远中向上的根管弯曲度最大,下颌尖牙在唇舌（腭）向上的根管弯曲度最大;上颌侧切牙在近远中和唇舌（腭）2个方向上的根管弯曲半径及弯曲长度均较小。结论壮族人群恒前牙根管弯曲情况较复杂,其下颌切牙Ⅱ、Ⅲ、Ⅳ型根管发生率较高。     

上颌第一、第二恒磨牙牙根和根管系统的锥形束CT研究

目的：运用锥形束CT（CBCT）观察中国人群双侧上颌第一、第二磨牙的牙根和根管系统的解剖形态,为临床根管治疗提供依据。方法：选择200名患者的双侧上颌第一、第二恒磨牙（上颌第一恒磨牙354颗、上颌第二恒磨牙360颗）的CBCT扫描数据,使用NNT软件分析上颌第一、第二恒磨牙的牙根数、根管数、根管分型以及双侧对称情况。结果：上颌第一、第二磨牙主要为三根（99.44%和84.44%）。上颌第二磨牙的单根和双根较多见（15.28%）,其根管系统形态复杂,在根尖区有融合趋势。上颌第一磨牙的根管系统主要为3根四根管（78.97%）。上颌第二磨牙的三根管和四根管发现率接近（分别为47.37%和51.64%）。上颌第一磨牙的近颊根管系统主要根管分型为：Ⅳ型（57.79%）、Ⅱ型（19.83%）和Ⅰ型（15.58%）。上颌第二磨牙的近颊根管系统主要根管分型为：Ⅰ型（48.14%）、Ⅳ型（30.43%）和Ⅱ型（17.39%）。上颌第一、第二磨牙的远颊根和腭根主要为单根单根管,存在少量和罕见的变异。上颌第一、第二磨牙近颊根的根管数目和根管分型左右对称。结论：上颌第一磨牙近颊根管系统变异普遍存在,MB2根管为其主要的变异形式。上颌第二磨牙牙根数目和根管形态变异类型多,单根牙和双根牙的根管走向复杂多变。CBCT可以为识别根管形态提供准确依据。     

关中地区汉族成人前牙根管弯曲度调查

目的：了解关中地区汉族成人前牙根管弯曲情况。方法：采用间接影像学手段，运用改良的Schneider测量方法，利用电子测量尺进行测量，分析根管弯曲情况。结果：前牙多数为Ⅰ型根管，其中上颌尖牙根管弯曲发生率高（68．5％）。各牙位的弯曲发生位置偏根尖1／3处。上颌前牙有个别牙为近远中向S型根管弯曲。上颌尖牙根管弯曲度与年龄有显著相关关系（P=0．03）。结论：前牙根管弯曲情况复杂，上颌尖牙根管弯曲程度重。上颌尖牙根管弯曲度与年龄有显著负相关关系。     

上颌第三磨牙根管形态的显微研究

目的研究上颌第三磨牙根管的解剖形态并寻找牙根与根管之间的对应关系。方法从150颗患者被拔除的上颌第三磨牙中,筛选牙体较完整的融合根30颗和分叉根17颗,利用显微cT扫描后行三维重建,观察其根管全貌,并对根管类型进行统计分析。结果17颗分叉根的根管形态全部为3管型或4管型,其中15颗根管数目与牙根数目一致;30颗融合根则出现了多种根管形态,其根管数目为1～4个不等。结论上颌第三磨牙根管形态变异大,但分叉根的根管形态相对简单,而融合根的根管形态反而复杂,牙根和根管数目往往不一致。     

青少年下颌第一恒磨牙牙根及根管的锥形束 CT 研究

目的:应用锥形束CT(CBCT)分析青少年下颌第一恒磨牙牙根及根管形态。方法:收集2012-07~12拍摄CBCT的183例12~16岁青少年患者的366颗下颌第一恒磨牙的锥形束CT影像资料,记录患者年龄、性别、观察牙位及牙根数目、根管数目及根管形态,利用SPSS 19.0软件统计分析下颌第一恒磨牙牙根及根管数目的性别差异和左右侧差异。结果:纳入研究的366颗下颌第一恒磨牙中,近中单根者365颗,远中单根者282颗(77.05%),双根者83颗(22.68%),1颗牙为C形根。近中单根双根管者356颗(97.27%),单根一根管者9颗(2.46%);远中单根一根管者229颗(62.57%),单根双根管者53颗(14.48%),双根各一根管者83颗(22.68%);C形根3根管者1颗(0.27%)。牙根及根管数目在男女之间与左右侧之间差异均无统计学意义。结论:下颌第一恒磨牙以双根居多,牙根变异主要发生在远中根,远中舌根的发生率较高;性别间与左右侧牙之间无明显差异。     

上颌前磨牙根管变异及其与上颌窦关系的锥形束CT研究

目的:利用锥形束CT研究上颌前磨牙牙根及根管系统解剖形态,为临床提供影像学依据。方法:选取720例成人患者（18~67岁）的锥形束CT扫描图像,按年龄分为5组：18~28岁、29~38岁、39~48岁、49~58岁及>58岁组,分析上颌前磨牙牙根及根管数、根管类型、两根管口间距离、根管弯曲度、根尖到上颌窦底距离、左右同名牙的对称性等及与年龄的关系。采用SPSS21.0软件包对数据进行统计学处理。结果:上颌第一前磨牙多为双根管（89.72%）,根管类型以Ⅳ型最常见（57.78%）。上颌第二前磨牙单根管发生率（53.06%）略高于双根管（46.94%）,根管类型以I型（53.06%）为主。左右同名牙牙根及根管数目多为对称分布。上颌前磨牙单根、双根管检出率随年龄变化而变化,两根管口间距离与根管类型关系密切。上颌第一、第二前磨牙颊舌向弯曲的根管检出率分别为32.53%和21.50%,存在S形复杂弯曲根管。16.69%的上颌第二前磨牙与上颌窦为关系密切型（d≤0.05 mm）。结论:上颌前磨牙牙根及根管解剖结构复杂,左右同名牙呈对称性。根管形态、结构和类型存在增龄性变化,根管弯曲情况复杂,牙根与上颌窦关系密切。     

下颌前磨牙牙根形态和根管系统的锥形束CT研究

目的采用锥形束CT(Cone-beam computed tomography,CBCT)研究下颌前磨牙牙根及根管系统解剖形态特征。方法回顾148例患者288颗下颌第一前磨牙和218颗下颌第二前磨牙的CBCT影像,分析牙根和根管系统形态,采用Vertucci等提出的分类法对根管构型进行分类。结果 288颗下颌第一前磨牙单根牙285颗,双根牙2颗。三根牙1颗;根管Ⅰ型占77.78%,Ⅱ型0.34%,Ⅲ型2.08%,Ⅳ型0.69%,Ⅴ型14.58%,Ⅶ型1.04%,Ⅹ型0.69%,C型2.78%。218颗下颌第二前磨牙全部为单根;根管Ⅰ型占98.17%,Ⅴ型占1.83%。结论下颌前磨牙大多数是单根单根管。下颌第一前磨牙根管系统具有较大的变异性。下颌第一前磨牙多根管类型主要是Ⅴ型,C型根管的检出率也较高。而下颌第二前磨牙多根管的发生率远低于下颌第一前磨牙。多根管的分歧发生在根中或根尖1/3处。CBCT可用于下颌前磨牙复杂根管形态的评价。     

下颌第三磨牙的解剖形态观察

目的：探讨下颌第三磨牙的解剖外形及其根管口的形态特点,为牙体牙髓病的临床治疗提供理论依据.方法：收集临床拔除的下颌第三磨牙159颗,观察牙尖和牙根数目,测量牙体长度、牙冠最大近远中径和最大颊舌径;拍摄颊舌向和近远中向X线初始片;开髓、拔髓、疏通根管,体视显微镜测量各根管口之间的距离.结果：外形上,下颌第三磨牙根长大于冠长,近远中径大于颊舌径.单根居多,占54.09%,其次是两根,占40.51%.下颌第三磨牙的根管数目1～4,以两根管（55.35%）居多.S型根管14例,C型根管36例（22.80%）,其中Ⅰ型50.0%,Ⅱ型36.1%,Ⅲ型13.9%.多根管牙的各根管口之间的距离最小0.35 mm,最大5.00mm;均值2.13～3.95.结论：下颌第三磨牙根管系统较为复杂,可以出现C型、S型及弯曲根管.     

400颗上颌前牙根管弯曲情况的研究

目的了解上颌前牙根管弯曲情况。方法采用间接数字化X线成像技术拍摄400颗上颌前牙的近远中向和颊舌向X线影像,分析根管的弯曲情况。结果上颌前牙根管以Ⅰ型为主。上颌中切牙、侧切牙和尖牙只出现近远中向弯曲的比例为11.17%、16.19%、21.43%,只出现唇舌向弯曲的比例为39.59%、40.00%、29.59%,近远中向和唇舌向都存在弯曲的比例为4.60%、35.24%、24.49%。大约50%左右的上颌前牙根管存在中度弯曲;与上颌切牙相比, 上颌尖牙的弯曲度略大而弯曲半径略小。结论上颌前牙根管弯曲情况较复杂,其中以上颌尖牙为甚。充分了解根管的分型、弯曲度和弯曲半径是完善上颌前牙根管治疗的需要。     

应用锥形束CT对成人上颌前磨牙牙根和根管系统形态的研究

目的：运用锥形束CT（CBCT）观察中国人群上颌前磨牙的牙根和根管系统的解剖形态,为临床根管治疗提供影像学依据。方法：选择200名患者的双侧上颌前磨牙（上颌第一前磨牙、上颌第二前磨牙各358颗）的CBCT扫描数据,使用NNT软件分析上颌第一、第二前磨牙的牙根数、根管数、根管分型以及双侧对称情况。结果：上颌第一前磨牙主要为单根（65.92%）和双根（33.80%）。上颌第二前磨牙主要为单根（93.85%）。上颌第一前磨牙的根管系统主要为双根管（84.36%）。上颌第二前磨牙的根管系统单、双根管比例接近（分别为52.79%和46.08%）。上颌第一前磨牙主要根管分型为：Ⅳ型（48.32%）、Ⅱ型（24.30%）和Ⅰ型（12.56%）。上颌第二前磨牙主要根管分型为：Ⅰ型（51.68%）、Ⅱ型（21.51%）和Ⅳ型（14.25%）。上颌第一、第二前磨牙的根管分型左右对称（对称率分别为74.57%和81.29%）。上颌前磨牙根管系统的主要变异为：管间交通支、颊根C形根管和多根管（树形根管或神经根样根管）。结论：上颌第一、第二前磨牙的根管系统主要为单根管和双根管。术前了解根管形态的变异是治疗成功的关键因素。     

A Study of the Root Canal Morphology of Mandibular Anterior Teeth Using Cone-beam Computed Tomography in a Chinese Subpopulation

IntroductionThe purpose of this study was to investigate the root canal configuration of the mandibular anterior teeth using cone-beam computed tomographic (CBCT) imaging in a Chinese subpopulation.MethodsA total of 3,871 CBCT images of mandibular anterior teeth were collected from 648 patients who accepted CBCT projection as a preoperative assessment for implants or orthodontic treatment. The following items were recorded and evaluated: tooth position, root number, canal number, root canal type, the distance between the anatomic apex and the point at which the canal divided into 2 for mandibular anterior teeth with 2 root canals (excluding canines with 2 roots), and the distance between the 2 root canal orifices. The Fisher exact test was used to analyze the correlation between the number of root canals and tooth position.ResultsAll of the incisors in this study had 1 root, and 1.32% of the canines had 2 roots. The prevalence of 2 root canals in the lateral incisors (354, 27.36%) was higher than that in the central incisors (202, 15.71%) (P < .05) and the canines (81, 6.27%) (P < .05).ConclusionsThere is a high prevalence of 2 root canals in the mandibular anterior teeth of the studied Chinese subpopulation. This study provides detailed information about the root canal morphology of mandibular anterior teeth in a Chinese subpopulation.     

A cone-beam computed tomography study of root canal morphology of maxillary and mandibular premolars in a Turkish population

Aim. The aim of this study was to evaluate the root canal number and configuration of maxillary and mandibular premolar teeth by gender, intervals for decades, tooth position and unilateral or bilateral occurrence in a Turkish population using Cone Beam Computed Tomography(CBCT) scanning. Methodology. CBCT images of 5496 maxillary and mandibular premolars from 849 patients were evaluated. The following was evaluated in all the images: numbers of roots and root canals, the morphology of the root canal configuration according to the Vertucci classification, male–female differences in the tooth position and male–female differences in unilateral or bilateral occurrence. The reliability data were analyzed with a chi-square test. Results. The most prevalent root canal frequency was the two canals (86.2%) and type IV (76.9%) configuration for maxillary first premolar, one canal (59.7%) and type I (54.5%) canal configuration for second premolar. The incidence of one canal was higher in females and the occurrence of two or three canals was more common in males. The incidence of one canal was higher on the left side of maxillary premolars and the incidence of two canals was higher on the right side. Most mandibular first (93.5%) and second (98.5%) premolars had one canal. In general, females had one root canal of the mandibular premolar, whereas males had two or three canals. The type I configuration was most common and the incidence was higher on the right side. There were some differences found in the frequency distribution of the number of root canals and configuration of maxillary and mandibular premolar teeth according to intervals for decades. Conclusion. CBCT scanning provides comprehensive information about the root canal morphology of maxillary and mandibular premolar teeth. These data may help clinicians in root canal treatment of premolar teeth.     

BeeFill^TM2in1热牙胶根充系统根充时牙根表面温度变化

目的：研究用红外成像仪监测BeeFill^TM2in1热牙胶根管充填系统根充时牙根表面温度的变化。方法：选取因牙周炎拔除的上下颌单根管中切牙22颗用BeeFill^TM2in1热牙胶根充系统进行根管充填。用红外成像仪跟踪监测从根充开始到完成这一过程中牙根表面温度的变化。结果：牙根表面温度根充后比根充前上颌中切牙平均升高8.2℃,低于引起周围组织损伤的理论阈值温度;下颌中切牙平均升高11.6℃,高于引起周围组织损伤的理论阈值温度。结论：本研究表明BeeFill^TM2in1热牙胶根充系统根充时会引起上、下颌中切牙牙根表面温度升高,但下颌中切牙牙根表面温度升高可能会造成牙周组织损伤,在临床上要谨慎使用。     

下颌第二恒磨牙C形根管的影像学分析

目的通过比较分析离体下颌第二恒磨牙C形根管的X线片和锥形束CT(CBCT)表现,为临床诊疗提供参考。方法收集我院因牙周病拔除的下颌第二恒磨牙110颗,模拟临床拍摄颊舌向X线片,并进行CBCT扫描。统计C形根管的发生率及其类型。结果 110颗离体下颌第二恒磨牙中,通过X线片诊断为C形根管的46颗(41.81%),通过CBCT影像确诊为C形根管显示66颗(60.00%)。通过CBCT诊断为C形根管的离体牙中,其中Ⅰ类(融合型)26颗,Ⅱ类(对称型)22颗,Ⅲ类(不对称型)18颗。Ⅰ类中,C4截面形态主要在根管下段出现的频率较高,Ⅱ类中,C3在整个根管各段中出现的频率较高。Ⅲ类中,C1和C2主要出现在根管上段。结论具有C形根管的下颌第二磨牙基本可以通过X线片初步诊断,但如需了解其根管的详细信息则要通过CBCT扫描分析。     

上颌第二磨牙牙根根管数目的CBCT影像学观察

目的：利用锥形束CT（CBCT cone beam computed tomography）三维影像对上颌第二磨牙的解剖形态进行观察分析,明确其变异性,指导临床根管治疗。方法：对来我院老年牙髓牙体病科就诊的患者进行CBCT扫描与二次重建后,对上颌第二磨牙解剖结构观察分析。结果：CBCT检查老年患者265人,上颌第二磨牙435颗。在轴位影像和3D影像上根据牙根、根管以及牙根、根管的变异性共分为8种类型。单根单根管2.30%;1根2根管7.35%;1根3根管9.20%;2根2根管3.91%;2根3根管19.54%;3根3根管38.6%;MB217.5%;4根4根管2.29%。结论：上颌第二磨牙根的数目、根管的数目以及解剖形态变异性非常大,CBCT影像为临床根管治疗等提供了可靠的依据。     

Root canal systems of the mandibular and maxillary first permanent molar teeth of south Asian Pakistanis

AIM: The purpose of the present ex vivo study was to investigate variations in the root canal systems of mandibular and maxillary first permanent molar teeth of South Asian Pakistanis. METHODOLOGY: The root canal systems of a sample of 30 mandibular and 30 maxillary first permanent molar teeth extracted from South Asian Pakistanis were studied using a clearing technique. RESULTS: The mesial roots of the mandibular molar teeth typically presented with two canals (97%) of type II, IV or VI configuration. The distal roots of these teeth presented with a single canal (50%) of type I or V configuration or with two canals (50%) of type II, IV or VI. The prevalence of four root canals in two-rooted mandibular first permanent molar teeth was 47%. In maxillary molar teeth the mesial roots with a single canal (47%) were type I or type V; those with two canals (53%) were type II, IV or type VI. The distal and palatal roots that presented as a single canal (100%) were type I or type V configuration. The prevalence of four root canals in three-rooted maxillary first permanent molar teeth was 53%. CONCLUSION: It is concluded that four root canals in mandibular and maxillary first permanent molar teeth of South Asian Pakistanis is a common occurrence. The distribution of the different configurations of root canal systems in this population differed from that in Caucasian groups, suggesting that variations in root canal systems may be attributed to racial divergence.     

Vertucci’s Root Canal Configuration of 14,413 Mandibular Anterior Teeth in a Brazilian Population: A Prevalence Study Using Cone-beam Computed Tomography

IntroductionThis cone-beam computed tomographic (CBCT)-based study evaluated the root canal configurations of mandibular anterior teeth in a large Brazilian population, along with the influence of sex and the frequency of symmetry between the contralateral teeth.MethodsOverall, 2543 CBCT scans, including those of 4773 lower central incisors (LCIs), 4835 lower lateral incisors (LLIs), and 4805 lower canines (LCs), were analyzed. The scans were obtained from a private radiologic clinic using the PreXion 3D device (Yoshida Dental Mfg Co, Ltd, Tokyo, Japan) with a 0.14-mm voxel size; exposure parameters of 90 kV, 4 mA, and 19 seconds; and a field of view of 80 × 80 mm. Root canal anatomy was analyzed according to the Vertucci classification. Sex influence on the canal distribution and symmetry between the contralateral teeth were analyzed. The data were analyzed statistically and were considered significant when P < .05.ResultsAll LCIs and LLIs had 1 root, whereas 2.4% of LCs had 2 roots. Two root canals were observed in approximately 20% of LCIs and LLIs and in approximately 11% of LCs. The most common configuration was type I followed by type III. Bilateral symmetry occurred in a majority of the individuals (ie, 91% in LCIs, 87% in LLIs, and 87% in LCs). No sex influence was noted with LLIs and LCs (P > .05). However, LCIs showed a higher prevalence of 2 canals in men (P < .05).ConclusionsThe prevalence of 2 root canals in the mandibular anterior teeth in Brazilians was approximately 20% for central and lateral incisors and 10% for canines.     

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。