• Anatomy
• Bicuspid
• Cone-beam computed tomography
• East Asian people
• Tooth root

• case report
• cone-beam computed tomography
• distobuccal 2
• maxillary first molar
• rare root morphology

• C-shaped
• Enamel pear
• Fused root
• Maxillary molar
• Root canal treatment
• Supernumerary tooth

• Humans
• Anatomic Variation
• Cone-Beam Computed Tomography
• Dental Pulp Cavity/abnormalities
• Dental Pulp Cavity/diagnostic imaging
• Maxilla/diagnostic imaging
• Molar/abnormalities
• Molar/diagnostic imaging
• Retreatment
• Root Canal Therapy/methods

• C-shaped canals
• additional canals
• micro-CT
• number of canals
• second
• third and fourth mesio-buccal canals

• Adult
• Female
• Humans
• Male
• Middle Aged
• Young Adult
• African People
• Black People
• Dental Pulp Cavity/diagnostic imaging
• Dental Pulp Cavity/anatomy & histology
• Maxilla/diagnostic imaging
• Maxilla/anatomy & histology
• Molar/anatomy & histology
• Molar/diagnostic imaging
• South Africa
• X-Ray Microtomography
• Aged

• cbct study
• cone beam computed tomography
• mesiobuccal canal
• periapical radiolucencies
• root canal treatment

• cone-beam computed tomography
• dental operating microscope (dom)
• endodontic treatment
• maxillary second molar
• mesial buccal third canal
• root canal treatment (rct)

• C-shaped canal
• Radix Entomolaris
• cemento–enamel junction
• fused roots
• landmarks
• mesotaurodont
• micro-CT
• orifice
• pulp floor
• root morphologies

• Canal anatomy
• Classification
• Cone-beam computed tomography
• Endodontics
• Maxillary second molar

• classification
• cone-beam computed tomography
• dental anatomy
• endodontics
• maxillary second molar

• South Africa
• Dental Pulp Cavity/diagnostic imaging
• Dental Pulp Cavity/anatomy & histology
• Maxilla/diagnostic imaging
• Cone-Beam Computed Tomography/methods
• Molar/diagnostic imaging
• Molar/anatomy & histology
• Tooth Root/diagnostic imaging
• Tooth Root/anatomy & histology

• case report
• cone‐beam computed tomography
• maxillary second molar
• root canal morphology

• cone-beam computed tomography
• maxillary molar
• root canal therapy
• second mesiobuccal canal
• three-dimensional imaging

A major challenge in root canal treatment is the complex and variable root canal system. There are several methods of classification of root canal systems. Herein, we report a case of a maxillary second molar, the root canal system of which could not be classified according to any of the previous methods. Case Report. Cone-beam computed tomography (CBCT), used to visualize the root canal system of a maxillary left second molar with fused roots, revealed a type 1–3 root canal system in the buccal root and a type 1–1 root canal system in the palatal root. A dental operating microscope was used throughout the treatment, and the root canals were successfully obturated.

To the best of our knowledge, this is the first report on the classification of buccal roots of maxillary second molars. Clinical Significance. A dental operating microscope and CBCT play a vital role in mapping the root canal system to ensure that no canal is missed.

• CBCT
• Vertucci classification
• canal configuration
• permanent mandibular first molar
• root canal

• Carcinoma, Renal Cell
• Cone-Beam Computed Tomography/methods
• Humans
• Kidney Neoplasms
• Molar/anatomy & histology
• Molar/diagnostic imaging
• Tooth Root/anatomy & histology
• Tooth Root/diagnostic imaging

The aim of this study was to evaluate the prevalence and characteristics of C-shaped root canals in maxillary first (MFMs) and second (MSMs) molars in a Southwestern Chinese population using cone-beam computed tomographic (CBCT).

CBCT images of MFMs (n = 1488) and MSMs (n = 1547) from 1508 subjects enrolled in Guiyang Hospital of Stomatology between July 2018 to February 2021 were evaluated for the incidence and types of C-shaped root canals. Differences by age, sex, left or right side, and bilateral symmetry were also evaluated.

C-shaped root canals were present in 2.93% MFMs and MSMs (n = 3035) in the Southwestern Chinese population. A significant higher incidence was observed in the MSMs (5.24%) than in the MFMs (0.54%). Increased incidences were noted in teeth with fused root. Two major types and 5 subtypes of C-shaped canal system of maxillary molars were defined, and the most common type of C-shaped canals is fusion of mesial-buccal (MB) and distal-buccal (DB) canals (Type I subtype C). No significant gender and age differences were noted in the prevalence of C-shaped root canals in this population, and no significant difference was seen in its incidence in the left or right MFMs and MSMs. The bilateral occurrence was observed in 1.27% of the patients.

C-shaped root canals are more frequently present in MSMs than in MFMs in the Southwestern Chinese population, with Type I subtype C (MB-DB canal fusion) as the most common subtype and low incidence of bilateral symmetry.

This study aimed to compare the size and location of the traditional and conservative endodontic access cavities of the right maxillary first molar teeth, projected on the occlusal surface using cone-beam computed tomography (CBCT), to obtain an ideal access cavity.

Five hundred CBCT images of the right maxillary first molars, including 198 males and 302 females, were retrospectively evaluated using KaVo eXam Vision software. First, a rectangular coordinate system was established. The coordinates of 4 pulp horns and 3 root canal orifices, which projected on the occlusal surface, were marked on it. Two different access cavities were then created by connecting these points: (1) traditional endodontic access cavity (TEC) required removal of the entire roof of the pulp chamber to establish a straight-line access to the root canal system; (2) conservative endodontic access cavity (CEC) was formed by connecting the projection of each root canal orifice on the occlusal. Data were analyzed using Kruskal-Wallis and Pearson’s correlation tests at a 5% significance level.

The area of TEC was approximately 9.61 mm² for males and 8.91 mm² for females. The area of CEC was approximately 3.4 mm² for males and 3.16 mm² for females. The projections of all pulp horns and root canal orifices were in or near the central area of nine-rectangle-grid.

Compared with the traditional access cavity, creating a conservative access cavity was less invasive. Meanwhile, the access cavity should be limited to the central or near the central area of nine-rectangle-grid.

• Cone-beam computed tomography
• Turkish populatio
• fused roots
• maxillary molars
• root canal configuration

• Humans
• Cone-Beam Computed Tomography
• Dental Pulp Cavity/diagnostic imaging
• Maxilla/diagnostic imaging
• Molar/diagnostic imaging
• Tooth Root/diagnostic imaging

• cone-beam computed tomography
• double palatal root
• extra root
• fourth root
• maxillary molar
• root canal anatomy

One of the most complexes in root and canal anatomy is the maxillary first permanent molar. This study aimed to analyze the frequency of mesiobuccal (MB2) canal and its apical portals of exit, in patients belonging to different gender-age groups and determine the possible relation with sex and age.

A CBCT scan images were accessed from a documented database of 343 patients (178 male, 165 female), who had an oral and maxillofacial examination. The age of the patients ranging from 12 to 63 years. The frequency of the MB2 canal and its portals of exit apically were observed. Age and gender correlation were calculated using the χ2 test. P < 0.05 was considered significant.

A total of 634 maxillary first molars (335 male, 299 female) were included. The MB2 canal was found in 53.78% of the cases. A significantly higher incidence of the MB2 canal was detected in males than in females. No correlation in the presence and/or absence of the MB2 canal in terms of age. When MB2 canal present, a single apical foramen was observed in 66.28% of the cases, two apical foramina were present in 33.72% of the cases.

MB2 canals may be present in approximately half of the cases, from which one third of the cases have their own apical portal of exit.

• CBCT evaluation
• Frequency
• MB2 canal
• Maxillary first molar

•

Most of the scans showed three roots (92%), while two roots is (6.6%), four roots is (1.1%), and one root is (0.3%).

Root 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.

420 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.

Most 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.

Considering 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.

• Maxillary second molars
• Root canal anatomy
• Root morphology
• Saudi population
• Two-rooted maxillary molars
• Upper molars

As the complex anatomy of maxillary first molars is one of the major challenges in endodontic therapy, knowledge of the complicated root canal anatomy and configuration is crucial to ensure the success of endodontic treatment and prognosis. This article presents an endodontically managed left maxillary first molar with an unusual palatal root morphology. The available literature on the anatomic variation of maxillary first molars is also reviewed.

A 36-year-old man with no medical history presented to the Stomatology Department of Peking University Third Hospital complaining of a toothache during mastication in the maxillary left posterior region for approximately 3 mo. He had a spontaneous and intermittent toothache that had worsened, particularly at night. The diagnosis based on clinical examination, X-ray imaging, and cone beam computed tomography (CBCT) was symptomatic irreversible pulpitis. Nonsurgical endodontic therapy was performed for the left maxillary first molar. Five root canals revealed by CBCT included a special palatal root canal (1-2-1-shaped), two mesiobuccal root canals, and one distobuccal root canal. Evaluation of the CBCT images confirmed the root canal morphology and the clinician performed more effective cleaning, obturation, and therapy. Finally, the tooth was restored using composite resin, and the patient was satisfied with the result.

CBCT and a complete review of the literature may be beneficial for investigating the root canal system to achieve a biological and functional therapeutic effect.

• Maxillary first molar
• Root canal anatomy
• Morphology
• Endodontic treatment
• Cone beam computed tomography
• Case report

Anatomic variations in palatal canal morphology in maxillary first molars (MFMs) are relatively rare occurrences. Therefore, omission is common unless clinicians recognize their presence.

The aim of this report is to point out new signs that can be viewed as indicators of the existence of additional canals in the palatal root (PR) in this upper first molar endodontic retreatment case. Moreover, the role of preoperative cone-beam computed tomography (CBCT) in both discovering and determining the location of those additional canals will also be discussed.

Besides formerly discussed signs that indicate the existence of this canal, clinicians should also pay attention to other signals on periapical radiograph, including the aberrant divergence of a palatal canal at apical third and an unusual lesion occurring laterally in the periapical area of palatal root.

• Bifurcated palatal canal
• Cone-beam computed tomography
• Endodontic retreatment
• S-shaped canal
• Second mesiobuccal canal
• Upper first molar

The upper molars generally have three roots; therefore, different combinations of fusion can occur, increasing the possibility of finding more complex root canal systems. The purpose of this study was to evaluate the prevalence and characterization of fused roots in first and second maxillary molars using cone-beam computed tomography (CBCT) in a Colombian population.

A total of 1274 teeth were evaluated, of which 534 were maxillary first molars and 740 were maxillary second molars. Axial sections were made at the cervical, middle, and apical levels to determine the prevalence of root fusion and the types of fusion.

Overall, 43% of the molars (n = 551) presented some type of fused root. Root fusion was present in 23.4% of the maxillary first molars. The most frequent type of fused root was type 3 (distobuccal-palatal; DB-P) (58.9%). Root fusion was observed in 57.6% of the maxillary second molars, and the most prevalent type of fused root was type 6 (cone-shaped) (45.2%). Of the maxillary molars, 12.5% were classified as C-shaped.

Within the limitations of this study, there was a high prevalence of fused roots in maxillary molars in the Colombian population, mainly in the maxillary second molars. In first molars, the most common type of fused root was type 3 (DB-P) and in second molars, the most common type was type 6 (cone-shaped). Additionally, molars with root fusion presented variation at different levels of the radicular portion, with implications for treatment quality.

• C-shape canal
• Cone-beam CT
• Fused teeth
• Maxillary molars
• Root anatomy

• CBCT
• cats
• cone-beam computed tomography
• dental radiography
• dentoalveolar lesions
• oral diagnostic imaging

• Micro-computed tomography
• Morphology
• Root canal system
• Third molar

• anatomy
• endodontic treatment
• maxillary molars
• micro-CT
• root canal system

• Anatomy
• cone-beam computed tomography
• ethnic
• morphology
• prevalence
• root canal

The second canal of the mesiobuccal root (MB2) of the maxillary first molars (MFM) is difficult to detect in conventional radiographs and can be a major cause of failure in endodontic treatments. The aim of this study was to investigate the prevalence and anatomy of the MB2 by using high-resolution cone-beam computed tomography (CBCT).

Three radiologists examined 414 high-resolution CBCTs. Of these, the CBCTs of 287 patients (mean age 49.43±16.76) who had at least one MFM were selected, making a total of 362 teeth. Prevalence and its relation with gender and age of the patients, side of the tooth, and Vertucci’s classification were analyzed. Data were statistically analyzed (P<0.05).

A total of 68.23% of the teeth exhibited the MB2. The presence of the MB2 was equivalent in both genders and significantly higher in younger patients. There was no correlation between the presence of the MB2 in relation to both the sides of the MFM and the FOV size. Smaller FOV recognized higher Vertucci’s grades.

It was concluded that the prevalence of the MB2 canal in maxillary first molars in this Brazilian population examined with high-resolution CBTCs is 68.23%, being more prevalent in young patients. Gender and the side examined are no factors for determining the presence of MB2. Although the both FOVs of the high-resolution CBTCs (FOV 8 and 5) detect the MB2 canal, smaller FOV (FOV 5) is more accurate in the analysis of the internal anatomy of such root canals, according to the Vertucci´s classification.

• Cone-beam Computed Tomography
• High Resolution
• Maxillary First Molar
• Mesiobuccal Root

• Animals
• Cone-Beam Computed Tomography/veterinary
• Craniosynostoses/complications
• Craniosynostoses/veterinary
• Dog Diseases/diagnostic imaging
• Dogs
• Female
• Humans
• Male
• Radiography, Dental/veterinary
• Sensitivity and Specificity
• Stomatognathic Diseases/complications
• Stomatognathic Diseases/diagnostic imaging
• Stomatognathic Diseases/veterinary

• Cone-beam computed tomography
• maxillary first molar
• second mesiobuccal root canal

• Adolescent
• Adult
• Cone-Beam Computed Tomography
• Dental Pulp Cavity/anatomy & histology
• Dental Pulp Cavity/diagnostic imaging
• Female
• Humans
• Male
• Middle Aged
• Molar/anatomy & histology
• Molar/diagnostic imaging
• Young Adult

• Canal configuration
• cone-beam computed tomography
• mandibular molars
• maxillary molars
• root anatomy

Inadequacy to locate the second mesiobuccal canal (MB2) canal leads to the highest probability of endodontic failure in permanent maxillary first molars (PMFMs) and still remains a constant challenge for many clinicians. The aim of this study was to characterize the geometrical features between MB2 and other orifices of examined PMFMs using cone-beam computed tomography images.

A total of 108 teeth qualified in the cone-beam computed tomography image archives were enrolled in the present study. The intersecting point (T) was determined as the perpendicular line (h, altitude of triangle) projected from the vertex of the MB2 canal orifice to mesiobuccal canal orifice-palatal canal orifice line (MB1-P). We measured the geometric features of PMFMs with the MB2 canal, including the interorifice distances, area, altitude, and the ratio between the canal orifices.

The average interorifice distance was found to be 1.91 ± 0.59 mm for MB1-MB2, 5.73 ± 0.66 mm for MB1-P, and 4.11 ± 0.79 mm for MB2-P, with significant gender difference for MB1-MB2 distance. For the MB1-T distance, a significant difference was found between genders (P = 0.02), with males averaging 1.78 ± 0.07 mm, and females 1.48 ± 0.11 mm. For the MB1-P distance, the majorities of both genders were found in the 20–40% cut-off. A portion of the males exhibited a tendency towards the 40–80% cut-off, while females shifted in the reverse direction towards the 0–20% cut-off.

In clinical scenarios, these anatomical characteristics of the root canals system could be beneficial to locating the MB2 canal.

• cone-beam computed tomography
• maxillary molar
• morphology
• root canal

To evaluate the root and root canal morphology of the maxillary second molars (MSMs) in a native Chinese population by cone-beam computed tomography.

Cone-beam computed tomography images of 2412 MSMs from 1294 Chinese patients were analyzed to determine the number and morphology of the roots, the root canal morphology, the bilateral symmetry, and the correlations of these parameters with sex and age.

The percentage of fused roots increased with age, while the percentage of fused roots in women was higher than that in men. The percentage of second mesiobuccal (MB2) canals in MSMs with three separate roots was higher in men than women. Patients aged 31 to 40 years showed a higher prevalence of MB2 canals, while those aged ≥51 years showed the lowest prevalence of MB2 canals among both men and women. There was a significant difference in bilateral symmetry of MSMs between men and women.

Root fusion of MSMs increased with age, while the root canal morphology was more complex in patients of intermediate ages.

• Cone-beam computed tomography
• maxillary second molar
• root canal morphology
• root fusion

Variation in the root and canal morphology of the maxillary first molars is quite common. The most common configuration is 3 roots and 3 or 4 canals. Nonetheless, other possibilities still exist. The presence of an additional palatal root is rather uncommon and has been reported to have an incidence of 0.06 - 1.6% in varying populations studied. Whenever two palatal roots exist, one of them is the normal palatal root, the other is a supernumerary structure which can be located either mesiolingually (radix mesiolingualis) or distolingually (radix distolingualis). This case report describes successful endodontic treatment of a maxillary first molar with radix mesiolingualis and radix distolingualis. Identification of this variation was done through clinical examination along with the aid of multiangled radiographs, and an accurate assessment of this morphology was made with the help of a cone-beam computed tomography imaging. In addition to the literature review, this article also discusses the epidemiology, classifications, morphometric features, guidelines for diagnosis, and endodontic management of a maxillary first molar with extra-palatal root.

• Accessory root
• Maxillary first molar
• Palatal root
• Radix distolingualis
• Radix mesiolingualis
• Root canal treatment