Evaluation of root canal morphology of maxillary premolars: a cone‐beam computed tomography study

The aim of this study was to evaluate the root canal configuration of maxillary premolars using cone‐beam computed tomography (CBCT). CBCT images of 999 maxillary premolars from a database were analysed to determine the frequency of the number of roots, root canals and Vertucci's classification. The associations among these variables were evaluated by Chi‐square test (P < 0.05). In the first premolars, 42.2% of single‐rooted teeth had a type II configuration, whereas 98.7% of 2‐rooted teeth showed type IV. In the second premolars, type I was the most prevalent (49.9%). The presence of two roots was more prevalent in first premolars, and the presence of one root was more prevalent in second premolars (P < 0.05). Male patients had a higher percentage of two roots compared with female patients (P < 0.05). Type IV and I was more prevalent in first and second premolars respectively (P < 0.05). There was a high frequency of 2‐rooted and single‐rooted teeth among maxillary first and second premolars respectively.     

Symmetry of root anatomy and root canal morphology in maxillary premolars analyzed using cone-beam computed tomography

ObjectiveThis study aimed to use cone-beam computed tomography (CBCT) to evaluate the root anatomy and canal morphology of maxillary premolars in a Chinese population and determine their degree of bilateral symmetry.Design774 CBCT images were retrospectively analyzed, representing 1387 maxillary first premolars and 1403 second premolars. The number of roots and canals were recorded. The morphology of root canal systems was determined according to Vertucci’s classification. The symmetry of root and canal anatomies between maxillary contralateral premolars was further evaluated.ResultsThe most common anatomy of maxillary first and second premolars was one-rooted with two canals (58.0%) and one-rooted with one canal (50.3%), respectively. The typical canal morphology was type IV (42.7%) in maxillary first premolars and type I (50.3%) in maxillary second premolars. One-rooted maxillary premolars exhibited a higher variability in the canal morphology, compared to two-rooted or three-rooted teeth. Maxillary second premolars exhibited greater anatomic symmetry than first premolars. The root and canal numbers showed bilateral symmetry between 80.2% of maxillary first premolar pairs and 81.8% of second premolar pairs. Bilateral symmetry in both number and morphology of roots and canals was observed for 72.3% of maxillary first premolar pairs and 73.2% of second premolar pairs.ConclusionThe root anatomy and canal morphology of maxillary premolars in a Chinese population were quite diversified. Maxillary contralateral premolars demonstrated a high degree of symmetry in root and canal anatomies, which enables practitioners to better determine the nature of the root canal system during treatment of opposite homonymous teeth.     

上颌第一前磨牙影像学根管形态分析

目的采用锥形束CT(CBCT)探讨上颌第一前磨牙根管的解剖形态,了解其常规形态及变异形态。方法收集176例患者的双侧上颌第一前磨牙的CBCT影像学资料,CBCT资料使用NNT软件进行扫描观察,探究根管类型和根管分布情况。结果 352个上颌第一前磨牙根管分型:Ⅰ型30例(8.52%),Ⅱ型92例(26.1%),Ⅳ型225例(63.9%),Ⅵ型3例(0.85%),Ⅷ型2例(0.56%)。结论上颌第一前磨牙牙根形态多样,且根管形态的类型较为复杂。通过影像学诊断方法更加深入的了解其解剖形态,对临床治疗具有重要意义。     

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。     

Root form and canal morphology of mandibular premolars in a Jordanian population

AIM: To investigate the root canal anatomy of mandibular premolars in a Jordanian population. METHODOLOGY: Nine hundred extracted mandibular premolars were examined. After the length of the teeth was measured, the presence of developmental grooves and furcated roots was noted. Following the preparation of access cavities, pulp tissue was removed and the canal systems were stained. The teeth were then rendered clear by demineralization and immersion in methyl salicylate. Cleared teeth were examined and the following features were evaluated: (i) type of root canals; (ii) presence and location of lateral canals; transverse anastomosis; (iii) location of apical foramina; and (iv) frequency of apical deltas. RESULTS: The mean lengths of first and second mandibular premolars were 22.6 mm (18-27.5 mm) and 22.2 mm (16-26.5 mm), respectively. Although the majority of the specimens corresponded to Vertucci's classification scheme, analysis of this large data set revealed four additional root canal morphologies. Variable root canal morphologies were found in the mandibular first premolars; two separate apical foramina were found in 33% of the teeth with two canals, compared to 6.2% with one apical foramen. Teeth with three separate apical foramina were scarce (2.2%). The majority of the mandibular second premolars had a single canal; 72% of teeth possessed type I canal systems, whilst 22.8% of the roots had two canals with two separate apical foramina. CONCLUSIONS: The prevalence of multiple canals in the investigated Jordanian mandibular premolars was high, especially for the second mandibular premolar, in comparison with previous studies performed on populations of different racial origin.     

Anomalous mandibular premolars: a mandibular first premolar with three roots and a mandibular second premolar with a C‐shaped canal system

Aim To describe unusual variations in the root morphology and root canal systems of mandibular first and second premolar teeth extracted for orthodontic reasons. Summary Normally mandibular first and second premolar teeth have single roots with single canals. A 15‐year‐old patient presented for orthodontic treatment and two mandibular premolar teeth were examined post‐extraction. The mandibular first premolar exhibited three distinct, separate roots and the mandibular second premolar exhibited a C‐shaped root canal system. The coronal morphology of each of the mandibular premolars revealed dimensions and anatomy within normal limits. The incidence of a three‐rooted mandibular first premolar is approximately 0.2%. Key learning points ? Thorough clinical and radiographic interpretation is important in recognizing anomalous root and root canal systems. ? The most common forms of root and canal systems and its aberrations must be understood to realize variations from normal do occur. ? Successful root canal treatment requires an accurate diagnosis of the root canal system using all available aids. ? Value of microcomputed tomography in the study of anatomy ex vivo and cone‐beam tomography in clinical endodontics of complex premolar cases is increasing.     

Morphological variations of mandibular first premolar on cone-beam computed tomography in a Saudi Arabian sub-population

In-depth knowledge of common and aberrant pulp morphology is essential for appropriate diagnosis and treatment planning prior to commencing root canal treatment. Radicular morphology of mandibular premolars has been extensively studied. Considerable variation in the number of canals and roots found in these teeth has been reported.AimThe purpose of this study is to investigate the root and root canal morphology of mandibular first premolar among Saudi Arabian subpopulation in Aseer using CBCT.MethodsCone-beam computed tomography images of Mandibular first premolar were taken from 166 patients which were referred to Armed Forces Hospitals Southern Region (AFHSR), Khamis Mushayt, Asir region Saudi Arabia. All the images were assessed by two Evaluators (An Endodontist and a Radiologist). Inter-examiner reliability was determined and was assessed by KAPPA value.ResultsThe mandibular first premolar (n = 216) distributed as 120 teeth in female and 96 teeth in male. Out of the 120 teeth examined in female groups one canal was seen in 95 (79.2%) teeth, two canals in 19 (15.8%) teeth and three canals in 6 (5%) teeth where as in the Male group out of 96 teeth, 52 (54.1%) teeth showed one canal, 32 (33.3%) teeth with two canals whereas 12 (12.5%) teeth showed presence of three canals.Chi-Square test for mandibular first premolars demonstrated the chance of second canal in the mandibular first premolar more in male than female and these differences was statistically significant (P ≤ 0.05).ConclusionEndodontic therapy of mandibular premolars is a challenge for clinician because of their frequent morphological and anatomical abnormalities. Proper knowledge about number of root canals and canal configuration is a key to success in Endodontic. There is a great variability in different population regarding the root canal configuration in mandibular pre-molars. However, most studies state the mandibular first premolar has one root canal. Also, the most prevalent type of root canal found was Type I vertucci.     

上颌前磨牙牙根及根管形态的锥形束CT研究

目的研究上颌前磨牙牙根形态、三根管的发生率和根管解剖形态,为临床诊疗提供参考。方法选取珠海市口腔医院412名患者,共779颗上颌第一前磨牙,728颗上颌第二前磨牙的锥形束CT(cone-beam computed tomography,CBCT)扫描数据,分析上颌前磨牙的牙根及根管形态,三根管的发生率、双侧对称性、根管分叉位置等。结果上颌第一前磨牙三根管发生率为1.8%,上颌第二前磨牙三根管发生率为0.3%,上颌第一前磨牙三根管发生率显著高于上颌第二前磨牙(X^2=8.304,P=0.004)。上颌第一前磨牙三根管对称率为27.3%,上颌第二前磨牙无对称三根管结构出现。上颌前磨牙解剖形态可为单根、双牙根或三牙根,其内部根管形态复杂,存在七种Vertucci根管类型,上颌第一前磨牙以VertucciⅣ型为主,上颌第二前磨牙则以VertucciⅠ型常见。三根管上颌前磨牙的根管分叉位置多见于根中或根上1/3,16颗三根管上颌前磨牙都具有三个独立的根尖孔。结论上颌前磨牙根管形态复杂多变,CBCT对发现变异和额外根管具有重要辅助作用。     

Evaluation of root canal morphology of mandibular premolars in a Saudi population using cone beam computed tomography: A retrospective study

Objective

To investigate the root canal morphology of mandibular first and second premolars using Cone-Beam Computed Tomography (CBCT) in a Saudi population.

Root Canal Morphology of South Asian Indian Mandibular Premolar Teeth

Introduction

The purpose of this study was to study the root canal morphology of South Asian Indian mandibular premolars using a tooth clearing technique.

Methods

Two hundred mandibular premolar teeth were collected from different dental schools and clinics in India. After pulp tissue removal and root canal staining with Indian ink, the specimens were decalcified with 5% nitric acid, dehydrated in ethyl alcohol, and subsequently cleared in methyl salicylate.

Results

Of the 200 mandibular premolars, 100 were first premolars and 100 were second premolars. Of the first premolars, 94% had a single root, whereas 6% were 2 rooted. Seventy-six percent had a single canal, 22% had 2 canals, and 2% had 3 canals. Eighty-two percent had a single apical foramen, 16% had 2 foramens, and 2% teeth had 3 apical foramens. Eighty percent of teeth had type I, 6% had type II, 10% had type IV, 2% had type V, and 2% teeth had type IX root canal anatomy. Of the 100 second premolars, 92% had a single root, whereas 8% teeth were 2 rooted and fused. Fifty-eight percent of teeth had a single canal, and 42% had two canals. Eighty-eight percent had a single apical foramen, and 12% had 2 foramens. Sixty-six percent had type I, 30% had type II, and 4% had type V root canal anatomy.

Conclusions

A high prevalence of 2 canals was noted in the first and second premolars. Also, 20% of first premolars and 34% of second premolars had a root canal anatomy other than type I.     

CBCT study of root and canal morphology of permanent mandibular incisors in a Chinese population

Objective. To evaluate root canal morphology of permanent mandibular incisor teeth in a Chinese population using cone-beam computed tomography (CBCT). Materials and methods. CBCT images of Chinese patients were collected and 1553 permanent mandibular incisors in the images were included. The following observations on the included teeth were to determine the number of roots, root morphology and canal configuration. The root canal configurations were classified. The effect of gender on the incidence of the second canal was investigated. Results. Of permanent mandibular incisors, 86.8% had a single root with single canal. Mandibular lateral incisors (17.5%) had a higher incidence of a second canal compared with mandibular central incisors (8.9%) (p = 0.000). A slightly higher percentage of incidence of a second canal was found in males (14.6%) than in females (11.9%) (p = 0.129). Conclusions. Permanent mandibular incisors with two canals had a relatively low incidence in this Chinese population. The incidence of a second canal did not differ between males and females. CBCT is a valuable aid during root canal treatment.     

Root canal treatment of mandibular second premolar with four root canals: a case report

The importance of an accurate diagnosis of the morphology of the root canal system is a prerequisite for successful root canal treatment and has been emphasized throughout the literature. Root canal morphology of premolar teeth, either maxillary or mandibular, and the discrepancies between first and second premolars, have been investigated and reported. A case report is presented of the root canal treatment of a mandibular second premolar with four root canals. As far as the reviewed literature revealed, up to three root canals in mandibular premolars have been reported. No previous report of a similar case of four root canals in a mandibular premolar was found.     

Root Canal Shape of Human Permanent Teeth Determined by New Cone-Beam Computed Tomographic Software

IntroductionThe purpose of this study was to determine root canal cross-sectional shapes (RCCSSs) of human permanent teeth using new cone-beam computed tomographic (CBCT) software.MethodsRCCSS was determined on CBCT scans of 1400 teeth (422 patients) as follows:(1) circular,(2) conical/pyramidal,(3) oval/long oval,(4) flat/ribbonlike,(5) 8 shaped,(6) C shaped,(7) calcified,(8) trapezoidal,(9) drop shaped, and(10) other shapes. Root canal shapes were evaluated in the coronal and middle thirds, 2 mm below their beginning, and in the apical third, 1 and 2 mm short of the apical foramen. Categoric variables were described as frequencies and percentages and analyzed using the chi-square test. The level of significance was set at P = .05.ResultsMaxillary anterior teeth and maxillary first and second premolars had a circular RCCSS at 1 and 2 mm from the apical foramen in more than 45% of the cases. The most frequent RCCSS in the buccal canal of maxillary first premolars at 1 mm from the apical foramen was circular (71%) followed by flat/ribbonlike (10%) and oval/long oval (6%). In mesiobuccal roots of maxillary and mandibular first molars at 1 mm from the apical foramen, the circular shape was found in 52% and 49%, respectively.ConclusionsThe RCCSSs in human permanent teeth are variable according to the tooth group and root thirds. The highest frequency of the circular-shaped canal at 1 and 2 mm from the apical foramen was found in maxillary central incisors and mandibular first and second premolars. Oval-shaped canals were detected in practically all tooth groups and root thirds.     

Use of Cone-beam Computed Tomography to Evaluate Root Canal Morphology and Locate Root Canal Orifices of Maxillary Second Premolars in a Chinese Subpopulation

Introduction

The aim of this study was to investigate root canal morphology and locate root canal orifices of maxillary second premolars in a Chinese subpopulation using cone-beam computed tomographic imaging.

Methods

A total of 392 cone-beam computed tomographic images of maxillary second premolars were obtained from 238 patients who required a preoperative assessment for implant surgery or orthodontic treatment. The number of roots and root canals and root canal configuration were investigated and categorized using Vertucci's criteria. The distance between the root canal orifice and the anatomic apex and the distance between root canal orifices in those teeth with 2 root canals were measured and evaluated. The Fisher exact test was used to analyze the correlation between the number of roots and sex.

Results

Among the 392 teeth, 86.5% (n = 339) had 1 root; 45.4% (n = 178) of the teeth had 1 root canal, and 54.3% (n = 213) had 2 root canals that ranged from type II–type V. The majority of teeth with 2 root canals showed a type IV canal configuration (n = 79, 20.2%) followed by type II (n = 64, 16.3%), type III (n = 45, 11.4%), and type V (n = 25, 6.4%). Only 1 tooth had 3 root canals. No significant difference was found between the number of roots and sex (P > .05). Among the 213 teeth with 2 root canals, the most frequent distribution of the distance between the root canal orifice and the anatomic apex was 5–10 mm (n = 157). The distance between the 2 orifices of 189 teeth was 1–4 mm.

Conclusions

The frequency of teeth with 2 root canals was high in maxillary second premolars. The internal morphology of teeth with 2 root canals was variable. This study provided useful information about the root canal morphology of maxillary second premolars in a Chinese subpopulation.     

Radicular Grooves and Complex Root Morphologies of Mandibular Premolars Among Israeli Population

IntroductionMandibular premolars usually have one root and one root canal. Different studies found that up to 30% of mandibular premolars have more than one root canal, and up to 24% of mandibular premolars have C-shape canals. The purpose of this study was to investigate the root anatomy and the prevalence of complex root canal morphology in mandibular premolars in Israeli population.MethodsA total of 1020 Israeli patients' cone-beam computed tomography scans were screened and evaluated. A total of 1835 mandibular first premolars and 1678 mandibular second premolars were examined. Irregular root anatomy and different root canal morphologies were recorded and analyzed.ResultsThe overall prevalence of complex root morphology (types II–VIII) in mandibular first and second premolars was 21% and 2.8%, respectively. The bilateral prevalence of complex root morphology in mandibular first and second premolars was 46% and 29%, respectively. The prevalence of radicular grooves in mandibular first and second premolars with complex root morphology was 48% and 36%, respectively. No significant difference was found according to gender or the side of occurrence. However, complex root canal morphology was significantly found in mandibular premolars with radicular grooves.ConclusionsComplex root canal morphology frequently occurs in mandibular first premolars in the population of Israel. Radicular groove existence in mandibular first and second premolars is significantly related to complex root canal morphology.     

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.     

Mandibular premolar with three root canals—two case reports

The presence of three root canals in the mandibular premolar may sometimes be recognized when there is persistent postoperative discomfort following root canal therapy. This paper presents two cases of root canal treatment of mandibular premolars with three root canals including one mandibular first premolar and one mandibular second premolar. The possibility that there is more than one root canal in lower premolar teeth must be considered in the radiographic and clinical examination during root canal treatment.     

Analisi della morfologia radicolare e canalare di molari superiori ed inferiori in una popolazione Caucasica: studio in vivo alla CBCT

AimTo investigate the root and canal morphology of maxillary and mandibular permanent molar teeth in a Caucasian population by using Cone Beam Computed Tomography (CBCT).MethodsA total of 596 permanent molars were included. The number of roots, the number of canals per root and the root canal configurations according to the method of Vertucci were recorded.ResultsAlmost all of maxillary first molars (95.7%) had three separate roots; however, 40.3% of mesiobuccal roots had two canals (MB2). Of 157 maxillary second molars, 88.5% had three roots. Among the mesiobuccal roots, 15.1% had two canals. The majority of mandibular molars (100% of first molars, 89.4% of second molars) had two separate roots. Most distal roots had a simple type I configuration, whereas mesial roots had more complex canal systems, with more than one canal.ConclusionsCBCT is an efficient method of studying root canal systems.     

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。