上颌第一恒磨牙髓室底及根尖孔的观察

目的 研究上颌第一恒磨牙的髓室底形态,根管口的形态,根管口及根尖孔的数目和位置分布。方法 106颗离体上颌第一恒磨牙,暴露其髓室底,并用苏木素将根尖区染色,用肉眼观察法结合用光滑髓针、15号根管扩大器等探查以明确根管口数,根尖孔数及其位置分布。结果 上颌第一恒磨牙的髓室类似一个底在颊侧的三角形,38.68%为三根管口,61.32%为四根管口,左右分布无差异,四根管口者含一个远中颊侧根管口,一个腭侧根管口,近中颊侧根管又分偏颊、偏腭侧两根管口;远中颊、腭根的根尖均为单孔,近中颊根的双根尖孔率为51.8%,61.54%的根尖孔为侧方开口。结论 上颌第一恒磨牙的开髓洞形应为偏向近中的圆三角形,近中颊根的双根管检出率较高。     

锥形束CT结合手术显微镜在上颌磨牙颊侧根管口下方分叉患牙治疗中的应用

目的 探讨锥形束CT检查结合显微根管技术治疗上颌磨牙颊侧根管口下方分叉病例的临床效果.方法 选取需进行根管治疗的上颌磨牙304颗(上颌第一磨牙159颗,上颌第二磨牙145颗),开髓后记录髓室底根管口数目及位置,对术前X线片怀疑为颊侧根管口下方分叉的患牙,先在肉眼下探杳疏通根管,再根据牙科锥形束CT结果 在根管显微镜下在...     

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％。     

上颌第一磨牙近中颊根MB2根管研究

目的：观测上颌第一磨牙近中颊根MB2的存在率,根管口的位置及形态。方法：采用牙体硬组织切片机对拔除的上颌第一磨牙进行连续横断切片,并在显微镜下观测其近中颊根第二根管存在情况,根管口位置及根管形态。结果：220个上颌第一磨牙中有81个存在近中颊根第二根管,存在率为36．81％,近颊根第二根管口横切面形态为圆形或卵圆形,近颊第二根管口与近颊第一根管口,远颊根管口和腭根管口的位置关系呈斜四边形。结论：上颌第一磨牙近中颊根第二根管存在率较高,其开髓形状应为斜四边形。     

上颌第二磨牙近中颊根MB2根管的临床研究

目的研究上颌第二磨牙近中颊根第二根管的临床发现率。方法采用改良髓腔入口和探查近中颊根根管口与腭根根管口之间发育沟或暗线的方法研究上颌第二磨牙近中颊根第二根管的肉眼发现率。结果60例患者的64颗上颌第二磨牙中有19颗存在近中颊根第二根管，发现率为29．7％。结论改良髓腔入口和探查近中颊根根管口与腭根根管口之间发育沟或暗线的方法，有利于发现和治疗上颌第二磨牙近中颊根第二根管。     

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目的利用锥形柬计算机断层扫描（CBCT）研究上颌第一磨牙近中颊根第二根管（MB2）发生率、根管解剖形态以及根管口位置分布。方法随机选取2011-2013年航天中心医院口腔科20～30岁患者CBCT影像160张（男80张、女80张）。平行近中颊根长轴平面观察其根管形态，并按照Vertucci分类统计。水平面观察根管口的位置，记录MB、MB2及腭根根管口间距离以及MB、MB2根管口分别到腭根根管口连线夹角，并比较不同性别间差异。结果本研究观察了279颗上颌第一磨牙，其中存在MB2牙齿233颗，检出率为83．5％，不同性别间差异无统计学意义（P〉0．05）。不同类型的根管出现概率不同，各类型出现率男女间无差异。MB与MB2根管口间距男性为（2．195±0．504）mm，女性为（1．966±0．419）mm，差异有统计学意义（P〈0．05）。结论上颌第一磨牙MB2发生率高，不同类型MB2发生概率不同，男性与女性之间无差异。MB与MB2根管口间距在两性之间存在统计学差异。     

磨牙髓腔解剖研究及其临床意义

对４００个磨牙开髓部位、髓室底形态、根管口分布、根管数目、牙齿长度等进行初步研究，特别对上颌磨牙近中颊根形状与极管数目的关系作了分析，将髓室底形态归纳为４种类型；上颌磨牙分为３类６型、下颌磨牙分为３类４型，上颌磨牙近中颊根双根管的发生率第一磨牙为４０％，第二磨牙为２３％。     

成人上颌第一磨牙根长、根管数目及形状研究

目的：通过对离体上颌第一磨牙测量根长，观察牙根不同部位根管数目和形状，为临床治疗提供参考资料。方法：收集20岁以上人上颌第一恒磨牙，测量根长度后将牙根横切分为3部分：根上1／3、根中1／3和根尖1／3，在体视镜下观察不同部位的根管数目、形状。结果：上颌第一磨牙腭根、近颊根和远颊根长度分别是（13、82±1．51）mm、（13、06±1、12）mm和（11．64±0．85）mm。近颊根管上1／3双根管检出率为51．00％，根中1／3和根尖1／3分别为53．88％、54、09％；远颊根中1／3和根尖1／3偶见双根管。腭侧根管横截面以圆形为主，未见有双根或多根管存在；近颊根和远颊根管形状变异大，形状多样。结论：上颌第一磨牙腭根和远颊根长度相近，腭根比近颊根长约2—3mm；近颊根和远颊根管形状变异大，近颊根双根管约50％以上，偶见多根管。根管上1／3线条形时，根中1／3和根尖1／3多为双根管。     

离体上颌第二磨牙髓室底形态特点及根管口的定位研究

目的观察上颌第二磨牙的髓底形态特点及根管定位。方法51颗离体的上颌第二磨牙，其中5颗牙齿拍常规的烦舌向x线片，牙齿均用金刚钻在喷水下依釉牙骨质界横断牙冠（cememo—enamel junction，简称CEJ），取根侧部分为实验样品，用放大镜观察髓室底的解剖形态和根管口的位置。髓室底沟分5型。结果根管口总是位于髓室壁和髓室的交汇处，或位于牙根发育融合线的顶点。髓室底沟呈“Y”型的牙齿28颗（占55％．28／51），呈“7”形的牙齿11颗（22％），上述根管口均与牙根发育融合线相接，远中烦舌沟的牙齿5颗（10％），近中烦舌沟的牙齿1颗（2％），2个根管口的牙齿6颗（12％）。结论由于x线片上有时很难准确显示上颌第二磨牙牙根的形态，修复性牙本质或矿化常闭塞根管口，应该仔细地进行x线片阅读和临床探查，防止根管遗漏。     

左上颌第二磨牙2根管1例

男42岁,因左上颌后牙胀痛来我科就诊。检查:27远中邻面龋,近髓,未探及露髓孔,冷热刺激(-),牙髓活力检测(-),叩痛( )。诊断为27根尖周炎,采用根管治疗术。在开髓、探查根管口时发现远中颊侧根管口不明显,X线牙片显示该牙只有颊侧与腭侧二个根管。上颌第二磨牙多为近中颊、远中颊     

A scanning electron microscopic investigation of accessory foramina in the furcation and pulp chamber floor of molar teeth

Observations of the pulp chamber floor and furcation surface of human maxillary and mandibular first and second molars were made with the scanning electron microscopic to determine the incidence, size, and location of patent accessory foramina. Accessory foramina on both the pulp chamber floor and the furcation surface were found in 36% of maxillary first molars, 12% of maxillary second molars, 32% of mandibular first molars, and 24% of mandibular second molars. Mandibular teeth had a higher incidence (56%) of foramina involving both the pulp chamber floor and furcation surface than did the maxillary teeth (48%).     

Evaluation of the pulp chamber size of human maxillary first molars: an institution based in vitro study.

The aim of this in vitro study was to determine the morphological measurements of the pulp chamber and also to establish the relationship of the cemento-enamel junction (CEJ) to the roof of the pulp chamber of the maxillary first molars in an Indian population. One hundred extracted human maxillary first molars were used. Each molar tooth was radiographed by radio visiography (RVG). Measurements were made by using the grid option in RVG. The results (mean +/- SD; in mm) were as follows: distance from floor of the pulp chamber to the furcation = 2.7 +/- 0.63; distance from roof of the pulp chamber to the furcation = 5.34 +/- 0.9; distance from tip of the palatal cusp to the furcation = 11.58 +/- 1.01; distance from the tip of the palatal cusp to the floor of the pulp chamber = 8.86 +/- 0.68; distance from the tip of the palatal cusp to the roof of the pulp chamber = 6.2 +/- 0.66; height of the pulp chamber = 2.62 +/- 0.61. The results of these measurements revealed that the morphological measurements of the maxillary first molars in the Indian population were similar to that reported by previous studies; the roof of the pulp chamber was found at the CEJ in 96% of the specimens.     

Incidence of patent furcal accessory canals in permanent molars of a Turkish population

Aim To determine the incidence of patent furcal accessory canals in permanent molars of a Turkish population. Methodology Two‐hundred extracted teeth consisting of 50 maxillary first molars, 50 maxillary second molars, 50 mandibular first molars and 50 mandibular second molars from Turkish patients attending the Oral Surgery Department of the Faculty of Dentistry, ?stanbul University, ?stanbul, Turkey, were included in the study. After preparation of access cavities and removal of pulp tissue, the teeth were stored in 5.25% sodium hypochlorite for 1 h. Following double‐sealing of the access cavities, all tooth surfaces except the furcation regions were covered with nail varnish. The teeth were stored in 0.5% basic fuchsin for 1 week. The teeth were sectioned at the cemento‐enamel junction and the presence of patent furcal canals was established by examining the pulp chamber floor with a stereomicroscope (10×) to determine staining. Results Patent furcal accessory canals were detected in 24% of maxillary first molars, 16% of maxillary second molars, 24% of mandibular first molars, and 20% of mandibular second molars. No statistically significant differences were found between the tooth types. Conclusions In a Turkish population, the incidence of patent furcal accessory canals on the pulp chamber floor of maxillary and mandibular first and second molars ranged between 16 and 24%.     

再论磨牙髓腔解剖研究及临床意义

目的：恒磨牙髓腔解剖的再研究。方法：通过开髓、根管预备，测量扩大针进入根管角度和根管长度，冠颈横断观察。结果：髓室底形态有４型；根管口分布类型：上颌磨牙有２类５型，下颌磨牙有３类４型；扩大针进入根管角度及根管长度因根而异。结论：成功地进行牙髓、尖周病的治疗，熟悉髓腔解剖十分重要。     

Evaluating the potential key factors in assessing the morphology of mesiobuccal canal in maxillary first and second molars

The purpose of this study was to provide further information on the morphology of the root canals and pulp chambers of 100 maxillary first and 100 maxillary second molars, with particular reference to the anatomical relationship of the root canal patterns and the distance between mesiobuccal (MB) and mesiolingual (ML) orifices. Each transverse section was digitally imaged to measure the interorificial distance using a stereomicroscope. The angles of primary curvatures were determined in both buccolingual (clinic view, CV) and mesiodistal (proximal view, PV) directions and the canal configuration of the MB root was classified according to the Weine classification. The rhomboidal pulp chamber floor morphology predominated in each tooth type. The mean interorificial distance in both maxillary first and second molars was significantly shorter in type II compared with type III (P < 0.05). The interorificial distance was correlated with the primary curvature of MB canal in PV in maxillary first molars (P < 0.05), whereas the primary curvature of ML canal in CV was correlated with the primary curvature of ML canal in PV in maxillary second molars (P < 0.01). The evaluation of interorificial distance in both types of maxillary molars and the curvature of ML canal in CV in maxillary second molar can give valuable information to the clinician.     

Morphological measurements of anatomic landmarks in human maxillary and mandibular molar pulp chambers

The aim of this in vitro study was to measure critical morphology of molar pulp chambers. One hundred random human maxillary and mandibular molars (200 teeth in total) were used. Each molar was radiographed mesiodistally on a millimeter grid. Using a stereomicroscope, the measurements were read to the nearest 0.5 mm. Results were as follows (mean, mm): pulp chamber floor to furcation, maxillary = 3.05 +/- 0.79, mandibular = 2.96 +/- 0.78; pulp chamber ceiling to furcation, maxillary = 4.91 +/- 1.06, mandibular = 4.55 +/- 0.91; buccal cusp to furcation, maxillary = 11.15 +/- 1.21, mandibular = 10.90 +/- 1.21; buccal cusp to pulp chamber floor, maxillary = 8.08 +/- 0.88, mandibular = 7.95 +/- 0.79; buccal cusp to pulp chamber ceiling, maxillary = 6.24 +/- 0.88, mandibular = 6.36 +/- 0.93; and pulp chamber height, maxillary = 1.88 +/- 0.69, mandibular = 1.57 +/- 0.68. The pulp chamber ceiling was at the level of the cementoenamel junction in maxillary, 98%, and mandibular, 97% of the specimens. The measurements showing the lowest percentage variance were buccal cusp to furcation (approximately 11%) and buccal cusp to pulp chamber ceiling (approximately 14%). The measurements were similar for both maxillary and mandibular molars.     

牙科三维CT研究上颌乳磨牙髓腔

目的：测量上颌乳磨牙髓腔形态参数，为乳磨牙牙体解剖学提供基础数据，并供临床应用参考。方法：用牙科三维CT对20个上颁乳磨牙进行扫描并测量髓室相关参数。结果：上颌第二乳磨牙髓室颊舌向最大距离、根分叉处水平面腭侧根管近中远中向最大距离、颊侧近中根管颊舌向最大距离，均比上颌第一乳磨牙大（P〈0．05），而髓室高度较第一乳磨牙小（P〈0．05）。髓室近中远中向最大距离、髓室底最高点水平面到根分叉处垂直距离、根分叉处水平面根管其他测量值二者无显著性差异（P〉0．05）。左右分组比较无显著性差异（P〉0.05）。结论：牙科三维CT是一种精确测量牙体解剖形态的有效方法，熟悉乳磨牙髓腔解剖对于成功地进行牙髓、根尖周病治疗非常重要。     

Morphological measurements of anatomic landmarks in pulp chambers of human maxillary furcated bicuspids

The aim of this in vitro study was to measure key morphological features of pulp chambers from furcated maxillary bicuspid teeth. There were 107 random human maxillary bicuspid teeth used. Each bicuspid was radiographed using the Trophy RVG digital imaging system and a Belmont Acuray X-ray at 70 kVp. Measurements were made using the Digipan measuring mode of the Trophy system. Results were mean (mm): pulp chamber floor to furcation: 1.85 +/- 0.85; pulp chamber ceiling to furcation: 4.61 +/- 1.04; cusp to furcation: 11.55 +/- 1.12; cusp to pulp chamber ceiling: 6.94 +/- 0.70; pulp chamber height: 2.76 +/- 0.97. The measurements showing the lowest percentage variance were: cusp to furcation (9.70%) and cusp to pulp chamber ceiling (10.09%). The only measurement that was statistically the same across maxillary molars, mandibular molars and bicuspids was measurement "B," pulp chamber ceiling to furcation. The critical distance from cusp tip to pulp chamber ceiling in bicuspids was approximately 7.00 mm.