Evaluation of Root Canal Configuration of Maxillary Molars in a Brazilian Population Using Cone-beam Computed Tomographic Imaging: An In Vivo Study

Introduction

The aim of this study was to analyze and characterize root canal morphology of maxillary molars of the Brazilian population using cone-beam computed tomographic (CBCT) imaging.

Methods

Patients referred for a CBCT radiographic examination for accurate diagnosis and treatment planning were enrolled in the study. A total of 620 healthy, untreated, fully developed maxillary first and second molars were included (314 first molars and 306 second molars). The following observations were recorded: (1) number of roots and their morphology, (2) number of canals per root, (3) fused roots, and (4) primary variations in the morphology of the root canal systems.

Results

First and second molars showed a higher prevalence of 3 separate roots, mesiobuccal, distobuccal, and palatal, with 1 canal in each root (52.87% and 45.09%, respectively). Two canals in the mesiobuccal roots represented 42.63% of teeth, whereas mesiobuccal roots of second molars presented 2 canals in 34.32%. The most common anatomic variation in the maxillary first molar was related to the root canal configuration of the mesiobuccal root, whereas the root canal system of the maxillary second molar teeth showed more anatomic variables.

Conclusions

Mesiobuccal roots of maxillary molar teeth had more variation in their canal system than the distobuccal or palatal roots. The root canal configuration of the maxillary second molars was more variable than the first molars in a Brazilian population. CBCT imaging is a clinically useful tool for endodontic diagnosis and treatment planning.     

Root and canal morphology of Thai maxillary molars

AIM: To investigate the root and canal morphology of 268 maxillary permanent molars collected from an indigenous Thai population. METHODOLOGY: The cleaned teeth were accessed, the pulp dissolved by sodium hypochlorite under ultrasonication, and the pulp system injected with Indian ink. The teeth were rendered clear by demineralization and immersion in methyl salicylate. The following observations were made: (i) number of roots and their morphology; (ii) number of root canals per root; (iii) root-canal configuration in each root using Vertucci's classification with additional modifications; and (iv) presence and location of lateral canals and intercanal communications. RESULTS: All the maxillary first and second molars had three separate roots. Only, half (51%) of the maxillary third molars had three separate roots; the other half had fused or conical roots. The majority of the distobuccal (98.1-100%) and palatal (100%) roots had type I canals. Over half of the mesiobuccal roots of first (65%) and second (55%) molars had two canals. The most common (44.2%) canal configuration in mesiobuccal roots of first molars was type IV (two canals, two foramina). A variety of canal types were found in the mesiobuccal roots of second molars. Maxillary third molars showed the greatest diversity of canal morphology. There was an increase in the prevalence of lateral canals towards the apical part of the roots and intercanal communications were present in 16% of each of first, second and third Thai maxillary molars. CONCLUSIONS: The mesiobuccal roots of Thai maxillary molars possessed a variety of canal system types. Over 50% of the first molars had a second mesiobuccal canal. The palatal and distobuccal canals mainly had type I canals. Only, a small proportion (7.3-13.3%) of the roots exhibited lateral canals which were the most common in the apical third     

Symmetry of Root and Root Canal Morphology of Maxillary and Mandibular Molars in a White Population: A Cone-beam Computed Tomography Study In Vivo

Introduction

The aim of the present study was to use cone-beam computed tomography (CBCT) to analyze root canal anatomy and symmetry of maxillary and mandibular first and second molar teeth of a white population.

Methods

A total of 201 patients who required CBCT examinations as part of their dental diagnosis and treatment were enrolled in the present study. Overall, 596 healthy, untreated, well-developed maxillary and mandibular molar teeth (161 maxillary first molars, 157 maxillary second molars, 117 mandibular first molars, and 161 mandibular second molars) were examined by CBCT to establish the symmetry in root and canal anatomy between right and left sides in the same patient by evaluating the number of roots and root canals and the root canal configuration.

Results

Three separate roots with 3 separate canals was the normal anatomy of maxillary first and second molars. Most mandibular first and second molars had 2 separate roots, and the majority had 3 canals. In the present study, first molars, both maxillary and mandibular, exhibited greater asymmetry than the second molars. Maxillary first molars were found to be symmetrical in 71.1% of patients, whereas maxillary second molars were symmetrical in 79.6%. The remaining 28.9% and 20.4% of patients, respectively, showed asymmetry. Around 30% of the mandibular first molars and 20% of the mandibular second molars showed asymmetry.

Conclusions

The results of the present study reported a percentage of symmetry that varied from 70%–81%. These variations in symmetry should be taken in high consideration when treating 2 opposite molars in the same patient, because their anatomy may be different in up to 30% of the cases.     

下颌第二恒磨牙牙根及根管形态的锥形束CT研究

目的 使用锥形束CT扫描评估下颌第二恒磨牙牙根和根管解剖形态.方法 收集354例患者双侧下颌第二恒磨牙的锥形束CT图像,统计下颌第二恒磨牙牙根数目、根管数目和构型,以及C形根管的发生率.结果 下颌第二恒磨牙以双根最多,发生率为57.34%,C形根的发生率为38.28%;双根者近中根多为2-2型(80.54%),远中根多为1-1型(96.06%);C形根管的发生率为25.99%,左、右下颌的发生率没有统计学差异(P>0.05).结论 下颌第二恒磨牙牙根和根管解剖形态复杂多样,锥形束CT能为根管治疗提供参考.     

Evaluation of root canal morphology of human primary molars by using CBCT and comprehensive review of the literature

Objective Knowledge of primary tooth morphology is essential for clinical dentistry, especially for root canal treatment and dental traumatology. However, this has not been well documented to date with a large sample. This study was carried out to investigate the variation in number and morphology of the root canals of the primary molars, to study the applicability of cone beam computerized tomography (CBCT) in assessing the same and to provide a comprehensive review of the literature. Materials and methods A total of 343 primary molars, without any root resorption, were divided into four main groups including the maxillary first molars, maxillary second molars, mandibular first molars and mandibular second molars. All of them were analysed in CBCT images in the axial, sagittal and coronal planes. Various parameters such as the number of roots, number of canals, the root canal type, diameter of root and root canal and root canal curvature were studied. Results Primary molars in all four groups showed variability in the number of roots and root canals. As far as length of the roots was concerned, the palatal root of the maxillary molar was found to be longest, while the distobuccal root was shortest. In mandibular molars, the mesial root was longer than the distal root. The length of distobuccal root canal of the maxillary molars and the distolingual canal of the mandibular molars was found to be shortest. The number of roots and root canals varied from two to four and three to four, respectively. The maxillary molars exhibited more one-canal than two-canal roots. Conclusion The present study provides comprehensive information to the existing literature concerning the variation in root canal morphology of the maxillary and mandibular primary molar teeth. These data may help clinicians in the root canal treatment of these teeth.     

Analisi alla Cone Beam Computed Tomography della simmetria anatomica in molari superiori ed inferiori

AimTo analyze the symmetry in root canal configurations in the maxillary and mandibular permanent molar teeth of a Caucasian population using Cone Beam Computed Tomography (CBCT).ResultsOf 45 patients who had both maxillary first molars, 32 (71.1%) had perfect symmetry in the root and canal morphology of homonym teeth on the opposite side. As regards the maxillary second molars, the symmetry was observed in 43 patients (79.6%) of 54. Of 34 patients who had both mandibular first molars, 24 (70.6%) showed a perfect symmetry in the root and canal morphology of homonym teeth on the opposite side. As regards the mandibular second molars, the symmetry was observed in 47 patients (81%) of 58.ConclusionsCBCT is an exciting and clinically useful tool in studying root canal morphology and so the symmetry between homonym teeth.     

Root and canal morphology of the mesiobuccal and distal roots of permanent first molars in a Kuwait population--a clinical study

Aim To identify the number of roots and canal configurations in permanent first molars of the indigenous Kuwaiti sub‐population and compare them against a similar group of non‐Kuwaiti population in different age groups and gender, and to determine the frequency of a second canal in the mesiobuccal root of maxillary first molars and distal root of mandibular first molars that could be located and treated in routine practice without using magnification or special lighting conditions. Methodology A total of 220 permanent first molar teeth of patients scheduled for root canal treatment over a period of 1 year were included. Patients were identified and grouped according to their nationality as Kuwaiti and non‐Kuwaiti (which included Filipinos, Indonesian Indians, Srilankans, Egyptians, Saudi Arabians and Syrians). In both nationality groups, patients were successively distributed into four groups based on their age. The first age group included patients below 20 years, the second 21–30 years, the third 31–40 years and the fourth were over 40 years. The first three groups comprised of 15 male and 15 female patients whilst the fourth group had 10 patients of each gender. Teeth with open apices, resorptions and calcification were excluded from the study. The teeth included were both clinically and radiographically examined for number of roots, the canal configuration and the presence of the additional mesiobuccal and distal canals and recorded. The simplified classification of canal configurations proposed by Weine was utilized. Results The incidence of a second canal in the mesiobuccal (MB) root of maxillary first molars and the distal root of mandibular first molars was not influenced significantly by nationality and gender. All the 110 maxillary first molars treated had three roots; 58% of MB root had one canal and 42% had two canals. The majority of the mesial roots had Weine type II canal configuration when the second mesiobuccal canal was present. All distobuccal and palatal roots had a single or type I canal configuration. Of the 110 mandibular first molars that were treated, 96% had two roots and 4% had three roots. When present, the third root was located either buccal or lingual to the main distal root. Overall 51% of the single distal roots had one canal whilst 49% had two canals. The mesial root frequently had a Weine type II canal configuration as did the distal root when a second canal was present. Pearson’s correlation analysis of both molars revealed a significant (P < 0.05) negative correlation (r = ?0.274, r = ?0.144) between age and number of canals as well as the type of canal. Conclusions The incidence of a second canal in distal roots of permanent mandibular first molars was 49% in the Kuwaiti population and this was similar to other Asian ethnic populations. Adopting modified access and troughing procedures revealed a 42% frequency of MB2 canals in maxillary first molars. The incidence of a second canal in both mesiobuccal roots of maxillary molars and distal roots of mandibular molars decreased significantly with age; no differences were noticed amongst the nationalities and gender studied. The possibility of extra roots should be anticipated in mandibular molars.     

Root and canal morphology of permanent mandibular molars in a Sudanese population

AIM: To investigate variations in the root canal systems of first and second permanent mandibular molar teeth in a Sudanese population using a clearing technique. METHODOLOGY: Two hundred extracted first and second permanent mandibular molars from three cities in the state of Khartoum were studied. Access cavities were prepared and pulp tissue was removed by immersion in 5% sodium hypochlorite under ultrasonication; Indian ink was then injected into the root canal systems assisted by a vacuum applied apically. The teeth were rendered clear by demineralization and immersion in methyl salicylate before evaluation. The following observations were made (i) number of roots and their morphology; (ii) number of root canals per tooth; (iii) number of root canals per root and (iv) root canal configuration. RESULTS: Overall 59% of mandibular first molars had four canals with 3% having a third distolingual root. Seventy-eight per cent of second mandibular molars had two separate flat roots, whilst 10% were C-shaped. The most common canal system configurations were type IV (73%) and type II (14%). Inter-canal communications were more common in the mesial roots. The prevalence of inter-canal communications was 65% in first molars and 49% in second molars. CONCLUSIONS: In this sample of Sudanese teeth, 59% of the mandibular first permanent molars had four root canals whilst 10% of the mandibular second molars had C-shaped roots/canals.     

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。     

The root and root canal anatomy of maxillary molars in a Chinese population

Abstract The purpose of this investigation was to study the prevalence of fused roots, C-shaped roots, C-shaped root canal orifices and C-shaped root canals in the maxillary molars of a Chinese population. A total of 305 first molars and 309 second molars were collected in Taiwan. The teeth were demineralized and placed in methyl salicylate to make them transparent. Root fusion was examined and the pulp chamber floor was checked for C-shaped orifices. Chinese ink was then injected into the root canal system to demonstrate possible C-shaped canals. The maxillary first molars had the palatal root fused with the mesiobuccal root in 0.3% of the cases, and with the distobuccal root in 2.0%. Teeth with C-shaped roots existed in only 0.3% of maxillary first molars, while 6.2% of the maxillary first molars and 40.1% of the maxillary second molars had fused roots. The maxillary second molars had the palatal root fused with the mesiobuccal root in 18.1% and with the distobuccal root in 2.6%; the palatal root was fused with the mesiobuccal and distobuccal root in 8.1% of the material. The maxillary second molars had a C-shaped root in 4.5% and C-shaped root canal orifices with C-shaped root canals in 4.9% of the cases. Fused roots or incompletely separated roots are common in the maxillary second molars amongst Chinese people, while C-shaped roots and root canals in maxillary molars are not frequently seen.     

辽宁地区汉族人下颌第二恒磨牙牙根和根管数目的锥形束CT研究

目的：利用锥形束CT（CBCT）扫描评估辽宁地区汉族人下颌第二恒磨牙牙根和根管数目的情况。方法：调取于我院口腔科行CBCT扫描患者的图像资料,统计分析下颌第二恒磨牙牙根和根管数目的情况。结果：在900例下颌第二恒磨牙中,双根的发生率为51．22％,其中82％的近中根内为双根管,100％的远中根内为单根管;三根的发生率为2．18％;融合根的发生率为46．6％,其中完全融合的锥形根占5．71％,不完全融合的C形根（C型根管）占40．89％,C型根管发生率在男女性别间差异无统计学意义（p〉0．05）,以双侧对称性分布较多,单侧发生率以右侧为多。结论：在辽宁地区汉族人中,下颌第二恒磨牙以双根或融合根居多,c形根（C型根管）的发生率较高。     

Root and canal morphology of maxillary first and second permanent molar teeth in a Ugandan population

AIM: To investigate the root and canal morphology of permanent maxillary molar teeth from a Ugandan population. METHODOLOGY: Maxillary first (n = 221) and second molar (n = 221) teeth were collected from patients attending dental clinics in Kampala. Teeth were prepared using a clearing technique: the pulp chambers were accessed and the teeth placed consecutively into 5% sodium hypochlorite, 10% nitric acid, then methyl salicylate. Indian ink was injected into the pulp chambers to demonstrate the canal system. RESULTS: In the first molars, 95.9% of the teeth had separate roots. The mesiobuccal root was fused with the palatal root in 3% of specimens and with the distobuccal root in 0.5% of teeth. In the second molars, 86% of the teeth had separate roots. The mesiobuccal root was fused with the palatal root in 6.3% of specimens and with the distobuccal root in 6.8% of teeth. Apical deltas were more frequent in the mesiobuccal root when compared with distobuccal and palatal roots of both the first and second molars. A type I canal configuration (>75%) was the most frequent in all the roots of both the first and second molars. Canal intercommunications and lateral canals were more frequent in the mesiobuccal root when compared with other roots. CONCLUSIONS: The mesiobuccal root tended to have more variations in the canal system followed by the distobuccal root, whereas the palatal root had the least. The findings in root and canal morphology of this Ugandan population were different from previous studies, which may partly be attributed to racial differences.     

Use of cone-beam computed tomography to evaluate root and canal morphology of mandibular first and second molars in Turkish individuals

Objective: The aim of this study was to investigate the root and canal morphology of mandibular first and second molars in a Turkish population by using cone beam computed tomography (CBCT). Study design: CBCT images of mandibular first (n = 823) and second molar (n = 925) teeth from 605 Turkish patients were analyzed. The root canal configurations were classified according to the method of Vertucci. Results: The majority of mandibular molars (95.8% of first molars, 85.4% of second molars) had two separate roots; however, three roots were identified in 2.06% of first molars and 3.45% of second molars. C-shaped canals occurred 0.85% of first molars and 4.1% of second molars. Three canals were found in 79.9% of first molars and 72.8% of second molars. Most distal roots had a simple type I configuration, whereas mesial roots had more complex canal systems, with more than one canal. The most common root morphology of first and second molars is the two rooted morphology with three canals. Both the mesial and distal roots showed wide variations in canal anatomy with type IV and type I canal configuration predominating in the mesial and distal roots, respectively. Conclusion: Vertucci type I and IV canal configurations were the most prevalent in the distal and mesial roots, respectively, of both the mandibular first and second permanent molar teeth. Key words:Cone-beam CT, Turkish, mandibular molars, root and canal morphology.     

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。     

Root and canal morphology of Thai mandibular molars

AIM: To investigate the root and canal morphology of 351 mandibular permanent molars collected from an indigenous Thai population. METHODOLOGY: The cleaned teeth were accessed, the pulp dissolved by sodium hypochlorite under ultrasonication and the pulp system injected with Indian ink. The teeth were rendered clear by demineralization and immersion in methyl salicylate. The following observations were made: (i) number of roots and their morphology; (ii) number of root canals per tooth; (iii) number of root canals per root; (iv) root canal configuration in each root using Vertucci's classification, with additional modifications; and (v) presence and location of lateral canals and intercanal communications. RESULTS: Of 118 mandibular first molars, 13% had a third disto-lingual root. In three-rooted teeth, 80% of the main distal roots and 100% of the disto-lingual roots had type 1 canal systems. Of 60 mandibular second molars, 10% had C-shaped roots, the majority of which had type 1 (33%) or type IV (33%) canal systems. Of 173 third molars, 68% had two separate roots, 20% had fused roots and 11% had a single C-shaped root; the majority had two canals (61%). CONCLUSIONS: This study suggests that Thai molars exhibit features of both Caucasian and Chinese teeth.     

Root and root canal morphology of permanent mandibular first and second molars in a Kuwaiti population: A retrospective cone-beam computed tomography study

AimEndodontic diseases typically affect the mandibular molars. Understanding the complex morphology of the root canal system and its variations is necessary for successful endodontic treatment. The aim of this study was to evaluate the morphology of roots and root canals of mandibular first and second permanent molar teeth in a Kuwaiti population using cone-beam computed tomography (CBCT).Materials and methodsCBCT images of 651 mandibular first and second molar teeth were obtained from specialist government dental centers. The age, sex, root canal configuration, and number and type of roots were recorded. The data were statistically analyzed.ResultsThe most common canal configuration in the mandibular first and second molars was type II (65.6% and 54.4%, respectively), with no significant difference seen between the sexes (p = 0.234). The canal configuration was significantly different between the mandibular first and second molars (p < 0.001). Most teeth had two roots (94.5%); split roots were common (92.6%) and the number thereof varied significantly. Radicular grooves were most common on the lingual side (4.9%). C-shaped canals were present in 43 (6.60%) teeth. Additionally, one tooth had a confluent middle mesial canal and nine (1.4%) had radix entomolaris.ConclusionMandibular molars in our Kuwaiti population typically had two split roots with type II and IV canal configurations. The prevalence rates of C-shaped canals, middle mesial canals, and radix entomolaris were remarkably low.     

Root canal morphology of maxillary second molars in a Saudi sub-population: A cone beam computed tomography study

IntroductionRoot morphology and canal anatomy of maxillary molars shows several complexities and variations. Knowledge of these is essential for successful endodontic treatment. This study aimed to investigate the morphology of the maxillary second molars in a Saudi Arabian sub-population in relation to gender, age, and nationality, as well as to analyze the anatomical symmetry between the left and right side in each individual.Methodology420 digitized cone-beam computed tomography (CBCT) scans were collected, of which 351 scans met the inclusion criteria. Number of roots and canals at three different levels of the root in each case was counted at all available sides and compared on the basis of the study variables. Statistical significance was set at P ≤ 0.05.ResultsMost of the patients (n = 323, 92%) had three roots, while two roots (n = 23, 6.6%), four roots (n = 4, 1.1%), and one root (n = 1, 0.3%) were less frequently observed. A significant correlation between female patients and the presence of two canals, while male patients showed a higher correlation with the presence of four canals at all levels. There also was a correlation between Saudi participants and the presence of four canals at all levels. No significant correlation in symmetry between the left and right side root canal anatomy was found. There was an inverse relation between the number of canals and age.ConclusionConsidering the limitations in this study, it appears that the Saudi population is more likely to have three- and two-rooted maxillary second molars, with males and females showing greater tendencies to having three and two roots, respectively.     

A preliminary in vitro study of the incidence and position of the root canal isthmus in maxillary and mandibular first molars

AIM: To investigate in vitro the incidence and position of the root canal isthmus in extracted mesiobuccal roots of maxillary and mesial roots of mandibular first molars. METHODOLOGY: Fifty maxillary and 50 mandibular molars were included in the study. The mesiobuccal roots of maxillary molars and the mesial roots of mandibular molars were sectioned from their crowns in the furcation region and embedded in clear resin. Transverse serial 1-mm-thick sections from the apical 6 mm were prepared. The apical side of each section was stained with India ink and observed through a light microscope. The sample images were saved to disk using a digital camera and the root canals in terms of the number present and the incidence and classification of isthmuses. RESULTS: In the mesiobuccal root of the maxillary first molars, 70% had one canal, whereas 29.5% had two canals. In the mesial root of mandibular molars, 41% had one canal, whereas 59% had two canals. In some sections, more than two canals were found close to the apical foramen. The isthmus incidence was greatest 3-5 mm from the apex. In teeth having two canals, a complete or partial isthmus was frequently observed in the sections between 3 and 4 mm from the apex. Of the isthmuses present, 22% were complete and 37% partial in mandibular molars and 17.3% were complete and 11.7% partial in maxillary molars. CONCLUSIONS: The incidence of isthmus in the mesiobuccal root of the maxillary first molars and in the mesial root of the mandibular first molars was high, particularly in sections 3-5 mm from the apex. Cleaning the isthmus is a major challenge during root canal treatment.     

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.

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。