上颌第一恒磨牙近中颊根三根管1例

上颌磨牙近中颊根虽多为单根，但根管解剖复杂，其双根管发生率很高，但三根管较少见。现报告上颌第一磨牙近中颊根三根管并进行去髓术的一个病例。     

上颌第一磨牙近中颊根第二根管的临床研究现状

上颌磨牙近中颊侧根管研究大多集中在近中颊根第二根管(MB2)根管口的寻找、发现率、近中颊根的形态方面,关于其临床治疗方面的研究报道甚少,本文从MB2的临床发现率、根管口定位、疏通、预备和充填等方面对MB2在临床上的研究现状作一综述。     

CBCT法研究上颌第一磨牙根管形态

目的：探讨应用锥形束CT研究上颌第一磨牙牙根及根管形态的价值。方法选取70例患者83颗上颌第一磨牙的锥形束CT（cone beam computed tomogaphy,CBCT）影像,分析其牙根数目、根管数目及根管系统的解剖结构。参照Vertucci分类法对根管形态进行分类,统计近中颊根第二根管（the seconal mesiobuual canal, MB2）率。结果83颗上颌第一磨牙均为3个独立牙根,其中MB2的发生率为38.6%,近中颊根根管VertucciⅠ型（1?1）、Ⅳ型（2?2型）、Ⅱ型（2?1）、Ⅲ型（1?2?1）所占百分比分别为61.4%、18.1%、15.7%和4.8%。结论上颌第一磨牙根管系统复杂,CBCT影像可反映真实根管形态,为根管治疗提供参考。     

上颌第一恒磨牙近中颊根3个根管1例

<正>1病例报告患者,男,30岁,于2007年11月来我科就诊。主诉:左上后牙咀嚼痛1个月。检查:26(牙合)面见银汞充填体,叩(+),不松,颊侧偏远中牙龈见瘘管,无脓液溢出。X线示     

上颌第一磨牙近颊根MB2根管治疗1例

病人男,40岁。主诉右侧上颌后牙充填物脱落1周,要求补牙而就诊。病史:2年前患牙曾做治疗,之后出现牙龈肿胀,口服抗生素缓解。临床检查:16牙冠大部缺损,髓腔开放,冷刺激痛(-),叩诊(±),松动度(-)。     

新疆地区人群上颌第二磨牙牙根和根管形态的CBCT研究

目的 采用锥形束CT研究新疆地区人群上颌第二磨牙的牙根和根管形态，为本地区口腔临床诊疗提供参考依据。方法 对纳入研究的539例新疆地区人群的上颌第二磨牙，利用CBCT对其牙根形态、数目，根管形态、数目和弯曲度，牙冠颊舌径和近远中径以及对称性进行观察、分析和统计。结果 在1017颗上颌第二磨牙中，三根牙的检出率最高为85.2%，四根牙检出率最低为3.2%，不同牙位和性别在牙根形态上的分布存在统计学差异；MB2的检出率与年龄无统计学差异；56岁及以上年龄组的四根牙检出率最高。颊舌径、近远中径的平均测量值越大，其对应的根管数目越多。上颌第二磨牙的牙根数目和形态对称、根管形态及四种特征均对称方面较高，上颌第二磨牙近颊根管和远颊根管68%为重度弯曲，弯曲位于根中1/3较多。结论 新疆地区人群上颌第二磨牙以三根牙为主，对称率较高，弯曲程度大，但存在一些牙根和根管的变异，临床上可以运用CBCT来指导诊疗。     

上颌第一恒磨牙近中颊根第二根管口的定位研究

目的通过上颌恒磨牙近颊根与髓底参数的测量研究寻找近颊根(MB2)根管定位的方法,为上颌磨牙四边形髓腔入口的制备提供依据.方法选取新鲜拔除的上颌第一恒磨牙36颗,沿髓底平面截除牙冠,测量髓底参数,记录近中颊根根面外形,于MB1与MB2根管中插针示折摄X-线片,记录根管分型,将所得资料进行统计学分析.结果上颌第一恒磨牙近颊根根管分型与根形相适应2-1型根管的近颊根多为扁斜根(85.71%),2-2型根管的近颊根多为宽扁根(80%).MB1-MB2根管口距离在1～3 mm之间,平均距离为1.93 mm.2-1型与2-2型根管其MB1与MB2根管口的平均距离无显著性差异(P>0.05).MB1与MB2根管口至近颊根近中根面颈缘的垂直距离无显著性差异(P>0.05).结论临床医生可采用改进的四边形髓腔入口,在MB1根管口的腭侧、近中方向距MB1根管口1～3 mm 处,沿经过MB1根管口的与近中颈缘平行的直线上寻找MB2根管口.     

上颌第一恒磨牙MB2根管的治疗体会

1　材料与方法1.1　一般资料　在我科就诊的上颌第一恒磨牙牙髓炎或根尖周炎患者 ,在治疗中发现MB2根管共 5 2例 ,年龄 16 4 5岁 ,平均年龄为 2 2岁。其中 ,男 2 4人 ,女 2 8人。1.2　材料　牙科探针、不锈钢K锉、低速球钻、5 .2 5 %次氯酸钠溶液、氧化锌丁香油湖剂、标准牙胶尖等。1.3　方法　开髓、制备洞型 ,拔髓、5 .2 5 %次氯酸钠溶液冲洗髓腔 ,保证髓室底解剖形态清晰。MB2根管口一般在近颊根管口的峡区 (isthmus)内或在近颊根管口与腭侧根管口的连线上 ,先用牙科探针仔细探查根管口 ,再用小号K锉确认为MB2根管。最后常规预备并充…     

上颌第一恒磨牙根管弯曲度初探

目的:分析上颌第一恒磨牙根管弯曲发生情况、弯曲位置、弯曲方向及弯曲程度。方法:收集南京地区80例上颌第一恒磨牙,在根管中分别插入15#~20#扩大针,拍摄近远中向和颊舌向X线片,用Photoshop6.0软件测量分析根管弯曲位置、弯曲方向和弯曲角度。结果:1)上颌第一磨牙腭侧根管通畅、较直。2)远中颊侧根管在近远中方向有80%,颊舌方向有45%出现大于5°的明显弯曲,弯曲位置多位于根中1/3,且近远中向的弯曲明显大于颊舌向(P<0.05)。3)上颌第一恒磨牙近中颊根颊侧根管在近远中方向、颊舌方向分别有82.5%、77.5%出现大于5°的明显弯曲。两个方向上的弯曲程度无明显差异(P>0.05)。4)本研究中有35%的标本探通了近颊根舌侧根管,其在近远中向、颊舌向出现明显弯曲的比例达91%、83%。结论:上颌第一恒磨牙四个根管在近远中方向、颊舌方向均有不同程度的弯曲,其第二弯曲出现的情况也各不相同。     

A Cone-beam Computed Tomographic Study of Root and Canal Morphology of Maxillary First and Second Permanent Molars in a Thai Population

Introduction

Understanding tooth anatomy is crucial for effective endodontic treatment. This study investigated the roots and root canal morphology of maxillary first and second permanent molars in a Thai population using cone-beam computed tomographic (CBCT) imaging.

Association between the Mesiobuccal Canal Configuration,Interorifice Distance,and the Corresponding Root Length of Permanent Maxillary First Molar Tooth: A Cone-beam Computed Tomographic Study

IntroductionThe aim of this cone-beam computed tomographic study was to evaluate the association between the mesiobuccal root canal configuration (RCC), interorifice distance (IOD), and the corresponding root length of a permanent maxillary first molar tooth.MethodsOne hundred cone-beam computed tomographic scans obtained from the computerized data bank of the institute were studied. The IOD between the first mesiobuccal and second mesiobuccal canal was measured in the axial section where the second mesiobuccal canal was first visualized. The root length was measured from the cementoenamel junction to the root apex in the coronal and sagittal section. The associations of these parameters with the RCC (based on Vertucci’s classification) were evaluated.ResultsThe predominant RCC was observed to be Vertucci type II (89%). The mean root length with this configuration was 11.19 ± 1.35 mm. In type IV RCC, the mean root length was 9.13 ± 0.52 mm. A statistically significant association was established between the root length and RCC (P < .05). In roots with type II and type IV RCC, the mean IOD was 2.58 ± 0.04 mm and 2.62 ± 0.1 mm, respectively. No statistically significant relation was established between the IOD and the type of RCC (P > .05).ConclusionsThe length of the mesiobuccal root is an important anatomic parameter for predicting the type of RCC in the permanent maxillary first molar tooth.     

上颌第一前磨牙根管颊舌向弯曲情况的研究

目的研究上颌第一前磨牙根管颊舌向的弯曲情况。方法选择100个上颌第一前磨牙为研究对象,开髓并充分暴露根管口后,将1个K型锉插入根管内直至根尖孔处。利用数字成像系统（RVG）拍摄每个牙的近远中向影像,采用Schneider法测量根管的弯曲角度,计算弯曲半径和弯曲部分长度。结果1）100颗上颌第一前磨牙共有176个根管,88个根管存在颊舌向弯曲,其中53个位于根尖1/3;21个根管存在“S”形弯曲,其第一弯曲多见于根中1/3,第二弯曲均见于根尖1/3处。2）颊腭侧根管弯曲情况无统计学差异（P>0.05）,但“S”形根管第二弯曲的弯曲情况更为复杂。3）弯曲角度与弯曲半径无相关关系（r=0.002,P>0.05）,但与弯曲部分长度呈正相关关系（r=0.489,P<0.01）。结论上颌第一前磨牙根管颊舌向弯曲发生率较高,其中“S”形根管的弯曲情况更为复杂。     

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。     

使用手术显微镜对上颌第一磨牙近中颊侧第二根管应用解剖的研究

目的：使用手术显微镜（operating microscope,OM）研究上颌第一磨牙近中颊侧第二根管口（MB2）形态和解剖位置关系，为根管治疗时寻找根管口提供解剖学依据。方法：采用UNIVERSA300/FS2012手术显微镜，观察110个上颌第一磨牙的MB2根管口形态及其发生率。结果：上颌第一磨牙的MB2出现率为38%；根管口的形态为圆形和卵圆形。结论：使用手术显微镜可以有效地发现MB2。     

上颌第一磨牙根管弯曲度的实验研究

目的:分析上颌第一磨牙根管弯曲位置、方向及弯曲度。方法:收集80个上颌第一磨牙,在根管中分别插入15#-20#扩大针,拍摄近远中向和颊舌向X线片,用Photoshop6.0软件测量根管弯曲位置、方向和弯曲度。结果:上颌第一磨牙腭侧根管通畅、较直。远中颊侧根管80%在近远中方向、45%在颊舌方向有>5°的明显弯曲,弯曲位置多位于根中1/3,且近远中向弯曲度明显大于颊舌向(P<0.05)。近中颊根颊侧根管在近远中方向、颊舌方向分别有82.5%、77.5%出现>5°的明显弯曲。两个方向上的弯曲度无明显差异(P>0.05)。35%的标本探通了近颊根舌侧根管,其在近远中向、颊舌向出现明显弯曲的比例达91%和83%。结论:上颌第一磨牙四个根管在近远中向、颊舌方向均有不同程度的弯曲,其第二弯曲出现的情况也各不相同。     

3根型下颌第一恒磨牙远颊根及远舌根根管弯曲度的测量

目的研究3根型下颌第一恒磨牙远颊根及远舌根根管弯曲度的特点。方法从临床采集25颗拔除的3根型下颌第一恒磨牙,开髓揭顶后,将2支8号K锉分别插入远颊根及远舌根根管达根尖孔。RVG（radio visiography）数字成像系统采集牙齿在近远中向和颊舌向的X线数码牙片。将数码牙片导入图像分析软件ImagePro Plus6.0,分别用Schneider法和Weine法测量根管弯曲度及根管入角。结果 Schneider法测得远颊根根管在近远中向弯曲度为9.33°±5.08°,颊舌向为10.06°±5.73°,差异无统计学意义（P〉0.05）;远舌根根管在近远中向弯曲度为11.28°±7.30°,颊舌向为28.34°±13.76°,颊舌向弯曲度显著大于近远中向,差异有统计学意义（P〈0.001）。Weine法测得的各项目均值皆大于Schneider法,而且两者具有高度相关性（Pearson相关系数r=0.972,P=0.000）。远舌根根管在颊舌向根管入角为27.04°±8.85°,明显大于近远中向的13.15°±6.74°,差异有统计学意义（P〈0.001）。结论掌握3根型下颌第一恒磨牙根管弯曲的特点有利于根管预备取得成功。     

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.     

Maxillary molar root protrusion into the maxillary sinus: a comparison of cone beam computed tomography and panoramic findings

This study aimed to examine the prevalence of molar roots protruding into the maxillary sinus and to determine the panoramic radiographic signs as correlated with cone beam computed tomography (CBCT). CBCT images of 354 roots were assessed and classified into three types, according to the relationship between the root and maxillary sinus. The prevalence of root protrusion into the maxillary sinus was calculated then the panoramic images assessed. After excluding some unidentified roots on the panoramic images, 200 were investigated for panoramic signs, including (i) projection of the root apex into the sinus cavity, (ii) interruption of the maxillary sinus floor’s cortex, (iii) absence of periodontal ligament space, (iv) darkening of the involved root region, and (v) upward curving of the sinus floor. The respective correlation between the panoramic signs and CBCT types was assessed. Forty-six percent of roots showed protrusion into the sinus with the palatal root of the first molar having the greatest prevalence (33/200 roots). The panoramic signs ‘projection of the root apex in the sinus cavity’ and ‘darkening of the involved root apical region’ both strongly indicated root protrusion into the maxillary sinus (P < 0.05).