Root and canal morphology of maxillary first premolars in a Chinese subpopulation evaluated using cone-beam computed tomography

Comprehensive analysis of root canal morphology in maxillary premolars among the Pakistani subpopulation: a CBCT-based study

BACKGROUND

Understanding the root canal morphology is essential for the success of root canal treatment. Therefore, this study aimed to evaluate and analyze the root canal configuration of maxillary premolars using Cone Beam Computed Tomography in the Pakistani subpopulation.

METHOD

This cross-sectional study utilized CBCT scans from two distinct centres: Aga Khan University in Karachi and Jinnah MRI and Body Scans in Lahore. The CBCT images were visualized using GALAXIS version 1.9 (SICAT GmbH and Co. KG, Bonn, Germany), integrated within the Sirona Dental System (D-64625 Bensheim, Germany). The scanning parameters were standardized at 85 kV, 7 mA, with a 15-s exposure time and a voxel size of 0.16 mm. A total of 707 CBCT scans were collected, encompassing 2180 maxillary premolars. Root canal configurations were classified based on (Ahmed et al. Int Endod J. 2017;50(8):761-70). Statistical analyses were performed using SPSS version 26, employing the Chi-square test with a significance level set at p < 0.05.

RESULTS

The distribution of root canal morphologies varied significantly with age and gender. Among maxillary premolars, 50% exhibited the typical configuration of 2MPMB1 L1 (two roots, single canal in each buccal and lingual root), while 26% of maxillary right second premolars displayed 1MPM1 (one root, one canal). Overall, 1MPM1 accounted for 27.4% of the total cases in the second premolars. There was no statistically significant relationship between age and root canal distribution in either first premolars (p = 0.338) or second premolars (p = 0.833). Regarding gender, a significant difference was observed in the distribution of right maxillary 1st premolars (p = 0.022*), with a higher prevalence among females.

CONCLUSION

This study offers significant insights into the anatomical variations of root canals in maxillary premolars across diverse regional subpopulations in Pakistan. While specific root canal configurations were prevalent, the findings indicate no statistically significant correlation between age and root canal morphology in maxillary premolars. However, a notable gender disparity was observed in the distribution of the right maxillary first premolars.

Systematic review and meta-analysis of root morphology and canal configuration of permanent premolars using cone-beam computed tomography

INTRODUCTION

The efficacy of root canal treatment is greatly impacted by a thorough understanding of root canal anatomy. This systematic review and meta-analysis aim to thoroughly investigate the root morphology and canal configuration (RMCC) of permanent premolars (PMs).

METHODOLOGY

A comprehensive analysis was conducted following the PRISMA guidelines. Literature exploration was carried out across four electronic databases (PubMed, Embase, Cochrane, and Web of Science). The risk of bias assessment was conducted for the included studies utilizing the Anatomical Quality Assessment (AQUA) tool. Data analysis was performed utilizing SPSS and RevMAN5.3.3. The meta-analysis was applied with a 95% confidence interval to calculate odds ratios (OR).

RESULTS

Among the 82 selected studies, 59 studies exhibited potential bias in domain one (objective(s) and subject characteristics), followed by domain three (methodology characterization). The majority of maxillary PM1s had either single root (46.7%) or double roots (51.9%), while three-rooted variants were uncommon (1.4%). Conversely, most other PMs exhibited a single root. In terms of canal configuration, maxillary PM1s predominantly featured double distinct canals (87.2%), with the majority of maxillary PM2s displaying either a single canal (51.4%) or double canals (48.3%). Mandibular PMs were primarily characterized by single canals, accounting for 78.3% of mandibular PM1s and 90.3% of mandibular PM2s. Subgroup analyses revealed higher incidences of single-rooted and single-canalled PMs among Asians compared to Caucasians. Additionally, women exhibited a higher incidence of single-rooted PMs, while men showed a greater frequency of double-rooted PMs.

CONCLUSIONS

The comprehensive analysis indicated that maxillary PM1s predominantly possess double roots and double canals, whereas maxillary PM2s and mandibular PMs were primarily characterized by single-rooted with a single canal. Notably, single root and single canal were more prevalent among women and Asian samples.

Exploring age and gender variations in root canal morphology of maxillary premolars in Saudi sub population: a cross-sectional CBCT study

BACKGROUND

In complex teeth like maxillary premolars, endodontic treatment success depends on a complete comprehension of root canal anatomy. The research on mandibular premolars' root canal anatomy has been extensive and well-documented in existing literature. However, there appears to be a notable gap in available data concerning the root canal anatomy of maxillary premolars. This study aimed to explore the root canal morphology of maxillary premolars using cone-beam computed tomography (CBCT) imaging, considering age and gender variations.

METHODS

From 500 patient CBCT scans, 787 maxillary premolar teeth were evaluated. The sample was divided by gender and age (10-20, 21-30, 31-40, 41-50, 51-60, and 61 years and older). Ahmed et al. classification system was used to record root canal morphology.

RESULTS

The most frequent classifications for right maxillary 1st premolars were 2MPM1 B1 L1 (39.03%) and 1MPM1 (2.81%), while the most frequent classifications for right maxillary 2nd premolars were 2MPM1 B1 L1 (39.08%) and 1MPM1 (17.85%). Most of the premolars typically had two roots (left maxillary first premolars: 81.5%, left maxillary second premolars: 82.7%, right maxillary first premolars: 74.4%, right maxillary second premolars: 75.7%). Left and right maxillary 1st premolars for classes 1MPM1 and 1MPM1-2-1 showed significant gender differences. For classifications 1MPM1 and 1MPM1-2-1, age-related changes were seen in the left and right maxillary first premolars.

CONCLUSION

This study provides novel insights into the root canal anatomy of maxillary premolars within the Saudi population, addressing a notable gap in the literature specific to this demographic. Through CBCT imaging and analysis of large sample sizes, the complex and diverse nature of root canal morphology in these teeth among Saudi individuals is elucidated. The findings underscore the importance of CBCT imaging in precise treatment planning and decision-making tailored to the Saudi population. Consideration of age and gender-related variations further enhances understanding and aids in personalized endodontic interventions within this demographic.

CBCT Evaluation of Root Canal Morphology of Maxillary First Premolar in Saudi Subpopulation

Background and Objective

Clinicians must possess a comprehensive understanding of variations in canal morphology and configuration during endodontic procedures to enhance treatment success. This study aims to assess and analyze the canal configurations of maxillary first premolars using Cone-Beam Computed Tomography within the sub-population of Western Saudi Arabia.

Materials and Methods

In this cross-sectional study, following the acquisition of ethical clearance from Batterjee Medical College in Jeddah, Saudi Arabia, a retrospective examination of Cone-Beam Computed Tomography (CBCT) scans of maxillary first premolars in adult patients was conducted. The study focused on quantifying the number of canals and characterizing their configurations, with classification based on Vertucci's categorization.

Results

The study examined 399 CBCT images of maxillary first premolars, revealing that type IV canal configurations were the predominant morphology (56.9%), followed by type V (24.6%). Significant gender-related disparities were observed, with females displaying a higher incidence of types I and V canals. At the same time, males exhibited a greater prevalence of types IV and VI canals. Notably, no substantial associations were discerned between canal types and age groups.

Conclusion

Within the context of maxillary first premolars, type IV canal configuration emerged as the most prevalent. Gender-based distinctions were evident, with females predominantly presenting types I and V canal configurations, whereas males displayed a higher occurrence of types IV and VI canal configurations.

Characterization of the root and canal anatomy of maxillary premolar teeth in an Iraqi subpopulation: a cone beam computed tomography study

This study aims to evaluate the number of roots and root canal morphology types of maxillary premolars in relation to a patient's gender and age in an Iraqi population using two classification systems. Cone beam computed tomography (CBCT) scans of 1116 maxillary premolars from 385 patients were evaluated for the number of roots and root canal morphology types according to Vertucci's classification and Ahmed et al. classification systems. Differences in the number of roots and root canal morphology types with regard to tooth type, patients' gender and age groups were evaluated and the degree of bilateral symmetry was determined. Chi-squared test was used for statistical analysis. About 51.1% of the 1st premolars were double rooted. The majority (87.9%) of the 2nd premolars were single rooted. The three-rooted form presented in only 1.2% and 0.7% of the 1st and 2nd premolars, respectively. Vertucci Type IV (Ahmed et al. code 2MaxP B1P1) and Vertucci Type I (Ahmed et al. code 1MaxP1) were the most common canal morphology types in the 1st and 2nd premolars, respectively. Females showed a lower number of roots and a higher prevalence of Vertucci Type I configuration (P < 0.05). Younger age groups showed a higher prevalence of Vertucci Type I configuration (P < 0.05). Bilateral symmetry was seen in more than half of the maxillary premolars. There is a considerable variation in the number of roots and root canal configurations of maxillary premolars in the studied Iraqi population, with a significant difference by gender and age groups. Ahmed et al. classification provided more accurate presentation of the root and canal anatomy in maxillary premolars compared to Vertucci's classification.

Root Canal Morphology of Premolars in Saudis

AIM

This study aimed to evaluate root number and morphological variations of the root canal system in maxillary and mandibular premolars among the Saudi subpopulation.

METHODOLOGY

A total of 500 cone-beam computed tomography (CBCT) images were assessed, including 2442 maxillary and mandibular premolars. The evaluation encompassed the number of roots and canals and their configuration based on the Vertucci classification. Gender differences were considered, along with the position of premolars and unilateral or bilateral symmetry.

RESULTS

Maxillary first premolars predominantly exhibited two roots (82.6%), followed by one root (16.3%) and three roots (0.97%), with a majority having two root canals (83.6%). Regarding maxillary second premolars, the most common morphology was one root (66.6%), with two root canals (40.5%) observed more frequently than one root canal (38.1%). Mandibular first and second premolars mainly featured one root (84.8% and 96.1%, respectively) with one root canal (70.8% and 90.2%, respectively), whereas two root canals were less prevalent (2.3% and 1.8%, respectively). Three canals and three roots were rarely found in mandibular premolars (0.3%). Regarding maxillary premolars, males exhibited significantly higher type IV and mandibular type I root configurations compared with females. Conversely, regarding mandibular premolars, females showed significant mandibular type V and higher type I root configurations compared with males.

CONCLUSION

CBCT imaging facilitated precise assessment of root morphology and root canal configurations in maxillary and mandibular premolars. The present findings can aid dentists in diagnosing, evaluating case difficulty, and devising effective root canal treatments, particularly in patients from Saudi Arabia.

Assessment of the canal anatomy of the premolar teeth in a selected Turkish population: a cone-beam computed tomography study

BACKGROUND

Teeth may have additional roots and a different number of root canals. Overlooked root canals may cause endodontic failure. The aim of this study was to investigate the prevalence of root canals and the number of roots of premolars in a selected Turkish population.

MATERIALS AND METHODS

A total of 2,570 teeth from 1,438 patients were evaluated. The cone-beam computed tomography scans of 1,055 maxillary and 1,515 mandibular premolars were examined.

RESULTS

Type IV root canal morphology was observed most frequently in maxillary first premolars (77%), and the rates of single and double channel formations were very similar (51% and 49%, respectively). Of the second maxillary premolars, 57.4% had Type I morphology, and 89.9% of the teeth were single-rooted, while 68.6% had a single root canal. The most common formation was Type I (85%) among mandibular first premolars, and a single root was observed in 95.6% of these teeth. In addition, 87% of the mandibular first premolars had a single root canal. The second mandibular premolars mostly had Type I (95.4%) formation, and 99.3% of the teeth were single-rooted, while 96.9% had a single root canal.

CONCLUSION

According to our findings, 51% of maxillary first premolars had a single root, 79.4% had two root canals, and 77% had Type IV (77%) formation. Maxillary second premolars mostly had Type I formation. In addition, a single root and single root canal formation were most common. Mandibular first premolars generally had a single root and single root canal formation, but 13% had two root canals, and 6.4% had Type V formation. More than 95% of mandibular second premolars had Type I formation.

Prevalence of Second Root and Root Canal in Mandibular and Maxillary Premolars Based on Two Classification Systems in Sub-Population of Northern Region (Saudi Arabia) Assessed Using Cone Beam Computed Tomography (CBCT): A Retrospective Study

The objective of this paper is to assess the prevalence of a second canal in maxillary and mandibular premolars based on two classification systems of root canal morphology using Cone beam computed tomography (CBCT) images. A total of 286 CBCT scans from the archive of the Radiology department of a hospital were assessed for the presence of a second canal in maxillary and mandibular premolars. The canal configuration and its assessment was undertaken using Vertucci and Ahmed's classification. A Chi-square test was used to test the significance of the difference between gender and age. A total of 286 premolars were examined (217 mandibular premolars and 69 maxillary premolars); of these, 173 teeth (60.5%) were from males and 113 were from females (39.5%). Some 62% of maxillary left first premolars had two roots, followed by maxillary right first premolars (47%), and then maxillary left second premolars (30%) and maxillary right ones (27%), respectively. Type IV Vertucci were seen in maxillary premolars, while type I were ordinarily seen in the included mandibular premolars. Surprisingly, Vertucci type III was only found in mandibular left first premolars at a frequency of 2%. One orifice with two separate canals and two orifices of two distinct canals with two portals of exit were predominantly noticed with maxillary first premolars (² FP B¹ P¹) in 73% and 81%, respectively, followed by (¹ FP ²) 19%. The prevalence of a second canal in maxillary and mandibular premolars was low in the investigated premolars in comparison to the premolars that had just one root and canal, as assessed based on Vertucci and Ahmed's root canal system classification.

Maxillary Premolars with Four Canals: Case Series

The aim of this case series is to contribute to the better knowledge and management of the complex anatomical configurations of maxillary premolars with four canals. The paper explains the endodontic treatment of five maxillary premolars with four canals, with three buccal and one palatal orifices, in different patients. The cases report several approaches in the treatment of four-canal maxillary premolars including a conservative canal preparation with a hybrid shaping technique, endodontic microsurgery and the application of biomaterials. The use of an operating dental microscope, different operating strategies and the critical evaluation of radiographs are all necessary steps for the correct and safe endodontic management of these teeth.

Evaluation of Variations in Root Canal Anatomy and Morphology of Permanent Maxillary Premolars among the Emirate Population using CBCT

Background:

Many types of research have revealed that root canal anatomy differs by race and country based on various national populations, but no study has been conducted on the UAE population.

Objectives:

Identifying the most common morphology of the upper premolars in a group of local and non-local people in the UAE.

Methods:

Cone-beam computed tomography (CBCT) images of 215 intact maxillary premolars were analyzed. The Pearson Chi-squared test and the two samples t-test were applied.

Results:

Most of the maxillary first premolars were two-root formed (90%). Single-rooted teeth were less common (8%). Three-rooted maxillary first premolars represented a low frequency of 1.9%. Most of the maxillary second premolar teeth studied in this research (52%) had two roots. Almost all local and non-local populations had two canals for both first and second maxillary premolar. Only two maxillary first premolars (0.2%) had the three-canal morphology. The most frequent canal morphology in the maxillary first premolar group among local UAE and non-local was type V. The maxillary second premolar group among local UAE was type II (32%). In non-local UAE, type V (25%). In addition, six types of uncommon canal anatomic variants (types 1-2-3, 2-3-2, 3-2-1, 1-2-3-2, 2-1-2-1, and 3-2) were discovered in 3.7% of local UAE and 36.3% of non-local UAE.

Conclusion:

The results suggest a more quantitative approach to maxillary first and second premolar access cavity preparation in the UAE population to prevent errors and iatrogenic damage when identifying the canals.

Root canal morphology of 1316 premolars from Brazilian individuals: an in vivo analysis using cone-beam computed tomography

The aim of this study was to investigate the internal root canal anatomy of maxillary and mandibular premolars in a Brazilian subpopulation, in order to establish the prevalence of the different configurations proposed by Vertucci. Three hundred and ninety-eight cone-beam computed tomography scans were collected from a private imaging clinic database in Rio de Janeiro, including 217 maxillary and 226 mandibular scans. A total 1316 premolars (594 maxillary and 722 mandibular) were evaluated using an image viewer, and classified according to Vertucci. Two calibrated examiners determined the frequency of each morphological Type. A third examiner reviewed discordant cases. The Kappa test was applied to verify inter-rater agreement, and Fisher's Exact Test to verify gender-related differences. The most frequent root canal configurations of maxillary first and second premolars were Type IV (73.86%) and Type I (47.18%), respectively. Type I was the most prevalent in mandibular first and second premolars (80.59% and 95.86%, respectively). Only Types I and VIII presented a statistically significant difference between sexes. Type I was more frequent in females and Type VIII in males. A highly significant frequency of Type I was found in both mandibular first and second premolars, whereas the most frequent maxillary premolar root canal configuration was Type IV for first premolars and Type I for second premolars.

Effects of root canal enlargement on unprepared areas and coronal dentine thickness of three-rooted maxillary first premolars with different root configurations: a stepwise micro-CT study

AIM

To evaluate the effects of progressive root canal enlargements on the unprepared surface area and remaining dentine thickness of three-rooted maxillary first premolars with different root configurations.

METHODOLOGY

Thirty three-rooted maxillary first premolars with 3 root configurations (n=10) were selected and scanned in a micro-CT device. The root canals were sequentially enlarged with rotary instruments sizes 30.02 (step 1), 30.04 (step 2), and 30.06 (step 3). After each step, a new scan was taken. Analysed parameters included morphometric measurements (length, volume and surface area), number of static voxels, and minimal dentine thickness. Statistic analyses were performed with one-way ANOVA post hoc Tukey tests and paired sample t-test at a significance level of 5%.

RESULTS

No statistical differences were observed among groups regarding the morphometric parameters and static voxels (p > 0.05). The minimal dentine thickness of the distobuccal root significantly changed depending on the root configuration (p < 0.05), while no differences were observed in the other roots (p > 0.05). A great variation in the position of the minimal dentine thickness was observed after preparation. Overall, mean percentage reduction of dentine thickness was higher in the buccal roots than in the palatal root (p < 0.05). In the mesiobuccal and distobuccal root, the number of slices with minimal dentine thickness lower than 0.05 mm increases 2 to 3 times and 3 to 4 times, respectively, from steps 1 to 3.

CONCLUSIONS

Instruments sizes 30.02 and 30.04 can be safely and effectively used to enlarge the buccal and palatal canals of three-rooted maxillary first premolars.

Three-dimensional evaluation of root canal morphology of maxillary first premolars: Micro–computed tomographic study

Aim

The aim of this in vitro study was to investigate the root and root canal morphology of maxillary first premolar teeth in a Kuwaiti population using micro–computed tomography (μ- CT).

Materials and methods

A total of 100 maxillary first premolars were scanned in a micro– computed tomographic device. The external anatomy (number of roots, distance from cementoenamel junction to apex, and presence of a palatal groove) and internal anatomy (number of canals and presence of apical deltas, lateral canals, and isthmi) of teeth were analyzed using descriptive analysis.

Results

The number of roots was one root (57 %), two roots (41 %), and three roots (2 %). The longest and shortest roots measured 17.7 and 11.2 mm, respectively. The palatal groove was present in 63.4 % of the teeth. According to Vertucci’s classification, type IV configuration was the most prevalent (53 %), followed by type II. A new root canal configuration type (1–2–1–2–1) was detected. Apical deltas, lateral canals, and isthmi were present in 33 %, 48 %, and 21 % of teeth, respectively.

Conclusion

Type IV canal configuration was the most common root canal configuration. A new root canal configuration type IX for (1–2–1–2–1) was proposed for Kuwaiti population. The μ-CT device could to be a better diagnostic tool for understanding the anatomy of the root canal system.

A Cone-Beam Computed Tomography (CBCT) Study of Root Anatomy, Canal Morphology and Bilateral Symmetry of Permanent Maxillary Premolar Teeth Among the Qatari Subpopulation

Objectives:

The study aims to evaluate the root anatomy, canal morphology, and symmetry of maxillary premolars teeth in a Qatari subpopulation using cone-beam computed tomography (CBCT).

Materials and Methods:

544 CBCT images of Qatari patients were analyzed by two endodontists. Tooth position, number of roots, canal configuration, and number of canals per root were investigated. A chi-square test was used to evaluate the association between gender and the number of roots. The interexaminer and intraexaminer were performed and documented.

Results:

The most common root anatomy and canal morphology observed in maxillary first premolars (MFP) were two roots (70.6%) with a single canal per root, while in maxillary second premolars (MSP), there was one root (84.3%) with a single canal (83%).

Type I Vertucci morphology was predominated in all roots of two-rooted MFP (97%), three-rooted MFP (100%), single-rooted MSP (42%), and two-rooted MSP (100%). The Chi-square test showed an association between gender and number of roots in both MFP and MSP, with a higher number of roots seen in men(P<0.05).

A symmetrical pattern was observed in the number of roots and canals in both maxillary premolars. But the symmetry for the type of canal configuration is higher in MFP (78%) than MSP (54%).

Conclusion:

In the Qatari subpopulation, most MFP had two roots with a predominance of type I Vertucci, while MSP had one root with type I. Contralateral MSP showed more diversity in canal configuration that should be considered during root canal treatment. CBCT is an effective diagnostic tool to investigate root anatomy and canal morphology.

Visual inspection of root patterns and radiographic estimation of its canal configurations by confirmation using sectioning method. An ex vivo study on maxillary first premolar teeth

Background

A thorough understanding of the original root and canal anatomy is a critical technical prerequisite for performing cleaning and shaping treatments. Therefore, this research aimed to characterize maxillary first premolar teeth' root morphology and canal architecture.

Methods

One hundred forty-two extracted human adult maxillary first premolar teeth have been retrieved. The extracted teeth were thoroughly cleaned and irrigated to eliminate any remaining debris or blood. They were then preserved in formalin solution until they were eligible for screening. To begin, a visual examination was employed to ascertain the number of roots and their geometry in each sample. Then, utilizing digital radiography in two plains, mesiodistal and distomesial, to further determine those parameters. Finally, a sectioning technique had been used to have the samples cut mesiodistally into slices to validate the internal root canal architecture and identify the number of root canals and their varieties in accordance with Vertucci's categorization system. The canal layout, the pulp chamber, and the root canals were all highlighted (marked) using a fine tip marker in a permanent orange hue to make the canal features more accessible and accurate to visualize. All of the processes were conducted by two highly qualified dentists. The sample size was estimated statistically using the Sealed Envelope program, and the percentage of each configuration was derived in proportion to the overall sample size in order to establish the percentage of each type in each configuration.

Results

From the 142 teeth examined, 42 (29.57%) had one root, 97 (68.31%) had two roots, and only three premolars (2.12%) had three roots. Concerning canal configurations, 100 teeth (70.43%) had type (IV) canal configuration, followed by 37 teeth (26.05%) had types (V), three teeth (2.12%) had type (VIII), and one tooth (0.70%) for each of type (I) and type (II).

Conclusions

The anatomical pattern of inspected maxillary first premolars are mainly two rooted and predominantly have a type (IV) canal morphology.

Anatomical Evaluation of Root and Root Canal Configuration of Permanent Maxillary Dentition in the Population of the Kingdom of Saudi Arabia

AIM

This study is aimed at combining the sample sizes of all studies on permanent maxillary teeth conducted in different regions of the Kingdom of Saudi Arabia (KSA) to obtain a large sample size that represents the population of the KSA. The outcome of these combined studies is compared with international studies in terms of the number of roots, number of canals, and canal configurations on the basis of Vertucci's classification. Methodology. The studies were systematically reviewed using the Preferred Reporting Items for Systematic Review and Meta-analysis chart. Studies were included in the analysis if they were conducted in the KSA, involved permanent human maxillary teeth, and had a sample of more than 10 teeth (power). By contrast, studies were excluded if they involved deciduous teeth in the sample size, investigated nonhuman teeth, were not conducted in the KSA, and were case reports, case series, review studies, and anomalies. Relevant literature was searched from PubMed, Scopus, Web of Science, Embase, Cochrane, and Direct Science by two calibrated teams, starting in August 2020, without time limits or language restrictions.

RESULTS

The database searches and cross-referencing identified a total of 19 relevant studies. All maxillary canines (N = 1,018) had one root, whereas 98.4% had one canal and 98.3% had Vertucci type I. Moreover, 63.2% of the maxillary first premolars had two roots, and 91.4% had two canals. The most common Vertucci root canal configuration was type IV (64.6%). The maxillary second premolars mostly had one root (84.4%) and one canal (50.4%). The most common canal configuration was Vertucci type I (47.1%). The majority of maxillary first molars had three roots (98.9%), 48.7% of which had three canals, and 46.4% had four canals. The most prevalent feature of the canal morphology of mesiobuccal roots was Vertucci type II (35.3%). The investigated maxillary second molars had three roots, 88.0% of which had three canals.

CONCLUSION

This systematic review represents the Saudi population since samples were combined from different studies from different regions of the country. Variations in findings were observed in the same group of teeth from different regions and the same region, while the overall combined samples results fell within the range of other international studies.

Root form and canal anatomy of maxillary first premolars: a cone-beam computed tomography study

The aim of this study was to evaluate the root and canal morphology of permanent maxillary first premolars in a Polish population using cone-beam computed tomography scanning (CBCT) and to compare the classifications by Vertucci and Ahmed et al. Images of 350 maxillary first premolars were analyzed. Scans were obtained from 226 patients: 131 women and 95 men. The root canal configurations were classified according to Vertucci and a new system by Ahmed et al. In addition, the number of roots and the level where roots bifurcated were identified. The results were submitted to statistical analysis. Most maxillary first premolars had two roots (69.1%). Most bifurcations were located in the coronal part of the root (44.2%) and the least in the apical part (15.3%). Bifurcation in the coronal part of the root was observed more often in the teeth of men than women. In turn, bifurcation in the central or apical part was significantly more common in women than in men. The most common canal configuration of the maxillary first premolars was type IV (78.2%) according to Vertucci and ²FPB¹P¹ (65.4%) according to the new classification. Among the remaining cases, almost all types of canals described by Vertucci, and many combinations of codes given in the new classification were demonstrated. The maxillary first premolars displayed a wide range of root and canal anatomical variations. The new system for classifying canal morphology based on Ahmed et al. is more accurate than the Vertucci classification.

Cone-beam computed tomography observation of maxillary first premolar canal shapes

A variety of shapes has been reported for the roots and root canals of maxillary first premolars. The purposes of the present study were to determine branching and shapes of the roots of maxillary first premolars, as well as age-related changes using slice images obtained with cone-beam computed tomography (CBCT) for dental use. CBCT-reconstructed images of 125 cases that included maxillary first premolars were used as subjects. Slice images at the cervical one-third, center, and apical one-third positions of the root were prepared. Root branching and number of root canals was determined at each measurement position in the images. The subjects were divided into three groups: younger than 30 years, 30 to 50 years, and over 50 years. The root canal morphology was compared among these age groups. Single-rooted premolars were the most frequent. As for number of root canals, a single-canal premolar was observed at the position of the cervical one-third in 33.6%, at the center in 35.2%, and at the apical one-third in 56.0%. Thereafter the subjects were divided into groups by age, namely, younger than 30 years, 30 to 50 years, and over 50 years old, and it was revealed that the ratio of the two-canal type increased with age. In regard to tooth morphology, it was confirmed that the two-canal type shows more frequent occurrence with aging in maxillary first premolar. Based on our findings, we consider that CBCT can be useful for determining the root canal morphology with complicated shapes.

Assessment of root morphology and canal configuration of maxillary premolars in a Saudi subpopulation: a cone-beam computed tomographic study

BACKGROUND

The objective of this study was to use CBCT to look into the root canal morphology of maxillary premolars in a Saudi Arabian subpopulation and associate the results to existing canal morphology classifications.

METHODS

The sample size for this analysis was 500 right and left untreated maxillary first and second premolars with fully formed roots from 250 Saudi residents (125 male and 125 female). The following observations were made using CBCT on the teeth related: (1) The number and morphology of roots; (2) The canal morphology for each root according to Vertucci's classification. The frequency and similarities between the right and left sides, as well as between females and males, were studied. The Chi-square test was used to assess the results.

RESULTS

Of the 500 maxillary first premolars studied, 199 teeth had one root (39.8%), whilst 293 (58.6%) were two-rooted. Three-rooted maxillary first premolars were found in 8 (1.6%). For maxillary second premolars, 416 premolars had one root (83.2%), whilst 79 (15.8%) had two roots and the rest 5 (1.0%) were three roots. There were significant differences of number of root were found between groups (p > 0.05). For maxillary first premolar, Type IV was the most frequent, accounting for 57.8% of the sample (n = 289), followed by type II (32.8%, n = 164). For maxillary second premolar, Type I was mainly occurrence 302 (60.4%), followed by Type II (16.4%, n = 82).

CONCLUSIONS

The majority of maxillary first premolars had two roots and two root canals, while one root and one root canal was the most common anatomical configuration for maxillary second premolars. Additional canal forms do occur on occasion, and clinicians should pay close attention to them.

Cone-beam computed tomography evaluation of C-shaped root and canal morphology of mandibular premolars

BACKGROUND

Mandibular premolars are complicated teeth to endodontically treat due to the anatomical variations that can present. The purpose of this study was to determine the presence of C-shaped configurations in mandibular premolars by cone-beam computed tomography (CBCT).

METHODS

380 mandibular first premolars and 308 mandibular second premolars cone-beam computed tomographic images were obtained from 292 patients (175 female and 117 male). Tooth position, number of roots, root canals, C-shaped root canal system configuration, level of canal bifurcation and radicular grooves were evaluated by two endodontists trained in CBCT evaluation; previously calibrated between them, and a radiologist with endodontic experience. Data were statistically compared by The Chi-square test (α = 0.05) to examine any significant difference between gender and C-shaped root canal system and any significant difference between C-shaped configuration according to Fan criteria and gender.

RESULTS

Overall 100% (n = 688) teeth examined, 19.2% (n = 132) had a C-shaped root canals system. 9.16% (n = 63) in male patients and 10.03% (n = 69) in female patients. The prevalence of C-shaped root canal system in mandibular first premolar was 83.33 and 16.66% in mandibular second premolars. According to Fan classification, the mandibular first premolars showed 3.63% as C1, 9.09% C2, 59.09% C3, 21.81% C4a, 1.8% C4b. Mandibular second premolars showed 13.63% as C1, 18.18% C2, 13.63% C3, 27.27% C4a, 9.09% C4b. Male patients showed 4.54% as C1, 3.78% C2, 22.72% C3, 11.36% C4a, 0.75% C4b, and 4.54% out of classification. Female patients showed 0.75% as C1, 6.81% C2, 30.03% C3, 9.84 C4a, 2.27% C4b, and 2.27% out of classification. The 53.36% canal bifurcation in mandibular first premolars and 50.09% in mandibular second premolars were in the middle third. No statistical differences were found between C-shaped root canal system and gender or C-shaped configuration according to Fan criteria and gender. P was < 0.05.

CONCLUSIONS

Within the limitation of this study, the presence of C-shaped anatomical system is relatively low in mandibular second premolars than in mandibular first premolars.

Evaluation of Palatal Furcation Groove and Root Canal Anatomy of Maxillary First Premolar: A CBCT and Micro-CT Study

Objectives

This study is aimed at investigating the root and root canal morphology by cone beam computed tomography (CBCT) and palatal furcation groove of the buccal root by microcomputed tomography (micro-CT) of maxillary first premolars in a Chinese subpopulation.

Methods

This study assessed CBCT images of 440 patients aged 14-80 years. Based on Vertucci's classification, the number of roots and the canal configuration were determined. Forty-eight maxillary first premolars with furcation grooves were analyzed by micro-CT in patients aged 18-25 years.

Results

Based on the CBCT assay, 70.22% and 29.32% of maxillary first premolars were 1 root and 2 roots, respectively. The configuration indicated statistical difference (P < 0.05) between male and female patients. The most common canal type was type IV and was found in 44.32% of cases, followed by type I in 27.84%, and then type II in 20.57%. Root bifurcations had 40.13% prevalence which was distributed more in the middle third than in the cervical and the apical third. For the micro-CT study, 95.83% of the furcation groove configuration was found in the bifurcated maxillary first premolars. The length varied from 1.02 to 7.63 mm. The mean depth of this groove was 0.57 mm in the root coronal, 0.47 mm in the root middle, and 0.22 mm in the root apical level. Palatal dentin width was smaller than 1 mm.

Conclusion

The anatomy of the root and root canal system and the irregular wall width of maxillary first premolars with furcation grooves may help dentists to understand the anatomical morphology and improve the outcomes of endodontic treatment.

Root Form and Morphology of Human Permanent Maxillary First Premolars of an Indo-Dravidian Population Based in Southern India: An In Vitro Study

Aim:

The aim of this study was to analyze root form and morphology of human maxillary first permanent premolars of an Indo-Dravidian population from southern India.

Materials and Methods:

Eight hundred and twenty-two maxillary first permanent premolars were cleansed and stored appropriately. Morphology and root form analysed, segregated into Groups (Gps): Gp I, Gp II, and Gp III, and later divided into subgroups (SGs) based on specific criteria. Gp I was divided into two SGs: SG A (minimal or absence of grooving in the root) (n = 252) and SG B (clear and defined longitudinal groove in the root) (n = 104), and Gp II was divided into SG C (roots dividing in coronal one-third) (n = 154), SG D (roots dividing in the middle one-third) (n = 158), and SG E (roots dividing in the apical one third) (n = 138). Gp III consisted of only one SG F (teeth with three roots) (n = 16). The groups were analyzed separately, their external root form and morphology were recorded. Root form was analyzed, and results were tabulated. This study was compared with other studies and statistically analyzed.

Results:

Gp II was common with an incidence of 54.74%. Gp I was the next most common with an incidence of 43.3%. Gp III was the least common with an incidence of 1.94%. The number and distribution of roots was also computed. Six types of root form were identified (Type [Ty] A = 30.65%, Ty B = 12.65%, Ty C = 18.73%, Ty D = 19.22%, Ty E = 16.78%, and Ty F = 1.94%).

Conclusion:

Awareness and assessment of root form, number preoperatively with regard to specific populations before initiation will pave way for successful outcome of therapy.

An efficacious horizontal angulation separated radiographically superimposed canals in upper premolars with different root morphologies

Objectives

To determine the effect of various horizontal beam angulations on radiographically separating superimposed canals in upper premolars with different external root morphologies.

Materials and methods

The independent variables were 1) three different external root morphologies of upper premolars (n = 30); one-root (A), fused-root (B) and two-root (C), 2) thirteen angulations (0° and mesial (Ms) and distal (Ds) shifts of 15, 20, 25, 30, 35, and 40°), and 3) the superimposed canal at the apex (apx) and 5-mm from the apex (5apx). The dependent variables were the percentage of radiographs demonstrating canal separation. The separated canal distances were analysed using analysis of variance (ANOVA) and Tukey HSD.

Results

Separation distances at apx and 5apx on one-root, fused-root and two-root premolar radiographs increased as the angulation increased. Ms angulations generated a higher separation distance (SepDist) in mm compared with the Ds angulations. Significantly different separation distances were observed from various horizontal shift angulations (p < 0.05). Percentage of canal separation from 0^o was achieved differently in different morphology of upper premolars (14-80%) at apx and 10-40% at 5apx. The 20-40Ms/Ds and 25Ds/30‒40Ms/Ds resulted in 100% of radiographs with canal separation for two-root and fused-root premolars, respectively, at apx and 5apx. Only the 35/40Ms resulted in 100% of radiographs with separation at apx in one-root teeth.

Conclusion

The ideal horizontal angulation which revealed the superimposed canal at the apx/5apx for one-root, fused-root, and two-root teeth are 35M/35M, 20D/20M, and 15M/20M, respectively.

Significance

The 25Ms was the optimal angulation which strongly recommended with the highest probability of separation and acceptable image quality in endodontic and prosthodontic treatment for unknown morphologies evaluated.

An Ex Vivo Study of Root Canal System Configuration and Morphology of 115 Maxillary First Premolars

INTRODUCTION

The aim of this study was to investigate the root canal system morphology of maxillary first premolars by means of micro-computed tomographic imaging in a Swiss-German population.

METHODS

The root canal configuration (RCC) of 115 maxillary first premolars (Mx1Ps) were investigated by means of micro-computed tomographic imaging and 3-dimensional imaging. The RCC and the physiological foramina results are described by a 4-digit system code.

RESULTS

Twelve different RCCs were observed in 30 single-rooted Mx1Ps; 2-2-2/2 (30.0%), 1-2-2/2 (13.3%), 1-2-1/2 (10%), and 2-2-1/2 (10.0%) were the most frequent ones. Seven different RCCs were observed in 2-rooted Mx1Ps (n = 81) in which the 1-1-1/1 (56.8%), 1-1-1/2 (29.6%), and 1-1-2/2 (8.6%) in the buccal root and 1-1-1/1 (92.6%) and 1-1-1/2 (6.2%) in the palatal root RCCs appeared most frequently. Three-rooted Mx1Ps (n = 4) showed a 1-1-1/1 (100.0%) RCC in all roots. The buccal root canal in 2-rooted Mx1Ps had 1 physiological foramen in 59.3% and 2 in 40.7% and 1 to 6 accessory foramina in 38.2%. The palatal root canal showed 1 physiological foramen in 93.8% and 2 in 6.2% and 1 to 2 accessory foramina in 14.8%. Single-rooted Mx1Ps showed 1 physiological foramen in 10.0%, 2 in 70.0%, 3 in 13.3%, and 4 in 6.7% and 1 to 3 accessory foramina in 46.7%.

CONCLUSIONS

The results of this study provide detailed morphologic RCC information of Mx1Ps in a Swiss-German population. Single-rooted Mx1Ps showed morphologic diversifications more frequently than 2- or 3-rooted Mx1Ps. Within 2-rooted Mx1Ps, the buccal root had higher RCC variety, accessory canals, and foramina number than the palatal root.

Cone-beam-computed-tomography of the symmetry of root canal anatomy in mandibular incisors

This study aimed to evaluate the prevalence of internal symmetry (the number and morphology of root canals) in the mandibular incisors using cone beam computed tomography (CBCT). A total of 302 CBCT scans involving 1,208 mandibular incisors were evaluated using the Vertucci's classification regarding the number and configuration of root canals. The central mandibular incisors exhibited two root canals in 22.6% of patients and lateral incisors in 24.3% of patients. Most teeth (76.4%) had a type I configuration (a single root canal, 1-1), 21.7% had type II (2-1), 1.1% had type V (1-2), and 0.8% had type IV (2-2). Teeth with a type-III configuration (1-2-1) were not found. In total, 17.5% of patients had a symmetric appearance of the two-canalled central mandibular incisors and 20.5% had a bilateral appearance of the two-canal lateral incisors. Moreover, in 12.3% of the patients, all four incisors showed two root canals. The highest degree of symmetry was found in incisors that had one root canal (central incisors: 217 of 302, lateral incisors: 229 of 302), followed by type 2-1 incisors (central incisors 50, lateral incisors 58). The influence of sex and age on the prevalence of symmetries was not significant. Concluding, the internal anatomy of the mandibular incisors cannot not be sufficiently predicted from the root canal anatomy of the contralateral tooth. Thorough clinical and radiographic inspection of each tooth remains mandatory to address the internal anatomy of the mandibular incisors correctly.

Root and canal configurations of maxillary premolars in a South African subpopulation using cone beam computed tomography and two classification systems

This cone beam computed tomography (CBCT) study aimed to describe the maxillary premolar anatomy of a South African subpopulation using two classification systems. A total of 601 premolars were evaluated. For each tooth, the root number and canal configurations were described using the classification systems devised by Vertucci (1984) and Ahmed et al. (2017). Correlations between root number and sex were determined using the chi-squared test (P = 0.05). Two roots were present in approximately half of all maxillary first premolars (54.1%, n = 171/316). The majority of maxillary second premolars displayed one root (78.2%, n = 223/285). Single-rooted maxillary second premolars were more common in females (P < 0.05). The Vertucci type IV configuration was most prevalent in the maxillary first premolars. In contrast, maxillary second premolars showed a greater tendency toward Vertucci's type I configuration. The classification proposed by Ahmed et al. indicated the most prevalent maxillary first premolar configuration to be ²MP B¹P¹. The most common configuration among the maxillary second premolars was ¹ MP¹. Diverse root and canal anatomical presentations were found in this subpopulation. Both classification systems adequately describe maxillary premolar anatomy; however, the system proposed by Ahmed et al. may more accurately describe complex teeth.

Root canal configuration and root wall thickness of first maxillary premolars in an Israeli population. A Cone-beam computed tomography study

Anatomical features of first maxillary premolars may greatly affect endodontic and following restorative treatments. The aim of this study was to evaluate root canal configuration and root wall thickness of first maxillary premolars using a preexisting CBCT database. A CBCT database of 400 first maxillary premolar was used to study canal configuration, presence of furcation-facing groove on the buccal root and root wall thickness. Root wall thickness was measured from axial CBCT slices at three critical points of the root: The most coronal part of the furcation-facing groove in the buccal root, when present, the CEJ level of the palatal root and 5 mm apically to the CEJ level of the palatal root. Vertucci Type IV configuration was the most common among all teeth, but in single-rooted teeth, Vertucci Type II was predominant. The mean thickness of the buccal root in the area of a furcation-facing groove was 1.1 (±0.2) mm, but in 39% of the cases, it was thinner than 1 mm. The mean thickness of the palatal root at 5 mm from the CEJ was 1.1 (±0.2), but in 28% of the cases, it was thinner than 1 mm. Thickness of root dentin walls of first maxillary premolars varies and may be limited at critical points in both buccal and palatal roots. In case the patient has a previous CBCT scan it may be useful for planning treatment of first maxillary premolars, in order to recognize and avoid potential risks such as furcation-facing groove, thin dentin walls in critical areas and presence of Type II Verucci canal, all of which may dictate less invasive procedures, using smaller files.

Root Canal Anatomy of Maxillary First Premolar by Microscopic Computed Tomography in a Chinese Adolescent Subpopulation

Objectives

To investigate the root morphology and root canal anatomy of maxillary first premolar using microscopic computed tomography (micro-CT).

Methods

324 maxillary first premolars were collected and scanned. The root and canal diameter, canal wall thickness, root taper, and cross-sectional shapes were determined in the single root with 1 canal (SR1C), single root with 2 canals (SR2C), and 2 roots with 2 canals (2R2C) by micro-CT.

Results

The results showed that single-rooted maxillary premolars were more common than other types. The incidence of SR1C, SR2C, and 2R2C reached 25%, 26.39%, and 26.39%, respectively. Root and canal diameters and canal wall thickness were decreased from coronal third to apical foramen. The three parameters and canal taper showed increases from buccal and palatal (BP) to mesiodistal (MD) aspects. The root canal tapers were smallest of the middle third level. The findings showed the different variations in 2R2C teeth. The root canal cross-sectional morphology in maxillary first premolars is complicated, including round, oval, long oval, flat canal, and irregular canal shapes. The distribution varied in different aspects.

Conclusion

Root canal morphology showed a wide variation and complicated structure. The single-rooted teeth were more common in the Chinese adolescent population, and the majority of maxillary first premolars have two canals.

Maxillary Permanent First Premolars With Three Canals: Incidence Analysis Using Cone Beam Computerized Tomographic Techniques

Aim

This study aimed to analyze incidence of three canals in human permanent maxillary first premolar teeth using cone beam tomographic techniques.

Materials and Methods

The samples were divided into three groups namely Group (GP) I (single rooted [n = 255]), GP II (two rooted [n = 326]), and GP III (three rooted [n = 8)]. The teeth were processed, mounted in arches, coded, and subjected to cone beam tomographic scanning. Incidence of three canals was evaluated by cone beam tomography, compared, and statistically analyzed.

Results

The percentage of incidence of three canals in human permanent maxillary first premolar teeth was 1.7% and there was no statistically significant difference of incidence of three canals between studies using cone beam and non-cone beam methodologies.

Conclusion

Clinicians should be aware of the variations they may encounter when endodontically treating a maxillary first permanent premolar and should apply this knowledge in a clinical scenario systematically.

Endodontic management of a three-rooted maxillary premolar: A case report

Maxillary premolars exhibit anatomical variations in the numbers of roots and canals, which pose a challenge during root canal therapy. In the present case report, we describe the endodontic management of a three-rooted maxillary premolar. A 47-year-old Yamani man was referred to the College of Dentistry, Taibah University for endodontic treatment of his right maxillary first premolar (#14). Periapical diagnostic radiography did not provide adequate information about the morphology of the root canal system and number of roots. Subsequently, a 3D cone-beam computed tomographic (CBCT) image was obtained, which revealed three roots in the aforementioned premolar. Root canal treatment was performed under magnification using a dental operating microscope, R25 RECIPROC blue NiTi single file system, and the Calamus dual 3-D obturation system. Clinicians should be able to predict the anatomical variations in maxillary premolars and have adequate knowledge and skills for managing such situations.

Evaluation of Root Canal Morphology of Maxillary First Premolars by Cone Beam Computed Tomography in Saudi Arabian Southern Region Subpopulation: An In Vitro Study

Introduction

The aim of this study was to investigate the root canal morphology of maxillary first premolars in Saudi Arabian subpopulation by cone beam computed tomography (CBCT).

Methods

One hundred maxillary first premolars were collected from the College of Dentistry at Jazan University and different dental centers in the southern region of Saudi Arabia. These teeth were cleaned thoroughly and were mounted in a plastic artificial mandible jaw to mimic soft tissue which was then placed in a water container. The 3D scan images were obtained with CBCT imaging (3D Accuitomo170) and evaluated on the basis of the number of roots, number of canals, and root canal configuration using Vertucci's classification.

Results

Out of the 100 maxillary first premolars, the majority of teeth had 2 roots (61%) followed by (36%) one root. Two canals were the most predominant with 97% and then 3% three canals, and no tooth presented with one canal. Type IV canal configuration was most prevalent (75%) followed by Type V (13%).

Conclusions

The CBCT provides enhanced and accurate information of root morphology, canal configuration, and its variations, thereby constituting an excellent alternative for radiographic diagnosis tool in the dental practice.

Three-rooted maxillary first premolars incidentally detected on cone beam CT: an in vivo study

PURPOSE

To explore the incidence and analyze the morphology of three-rooted maxillary first premolars (MFPs) incidentally detected on cone beam computed tomography (CBCT) scans.

METHODS

Of 1328 patients who underwent CBCT scans of the maxilla, only patients with three-rooted MFPs were selected. Morphological features, including the lengths and diameters of palatal, mesiobuccal (MB) and distobuccal (DB) roots, the positions of bucco-palatal (B-P) bifurcations, the distances between root canal bifurcations and cementoenamel junctions (CEJs) and the distances between the apical thirds of the roots, were measured. The canal configuration and the visibility of root canals were also evaluated.

RESULTS

A total of 16/1328 (1.2%) patients had one or two three-rooted MFPs, and a total of 22/2656 (0.8%) three-rooted MFPs were enrolled. The lengths and diameters of palatal roots were significantly greater than those of other roots. The positions of B-P bifurcations were located mainly at the middle third of the root. The median distances between root canal bifurcations and CEJs were 3 mm for B-P bifurcations and 5.2 mm for MB-DB bifurcations. The distance between MB and DB roots was significantly shorter than the distances between other root pairs. All teeth had a type VIII canal configuration. Palatal roots exhibited the best visibility of root canals, whereas the worst visibility was observed within DB roots. A gender-related relationship was observed only for the lengths of the roots.

CONCLUSIONS

The occurrence of three-rooted MFPs is not unusual; therefore, preoperative CBCT evaluation could be suggested whenever endodontic procedures are planned on an MFP.

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.

Root Canal Morphology of Maxillary First Premolars Using the Clearing Technique in a South Indian Population: An In vitro Study

Background:

The success of root canal therapy requires a good knowledge of root canal morphology. Literature review shows variations in a number of roots and canal morphology in studies done across the globe.

Aim:

The purpose of this study was to evaluate the root canal morphology in maxillary first premolars using the clearing technique in a South Indian population.

Methodology:

Two hundred and twenty-five extracted noncarious, nonfractured, sound maxillary first premolars were collected, cleaned, and were injected with India ink to stain the root canals. Teeth were then decalcified and cleared using methyl salicylate. Teeth were then viewed under a stereomicroscope to evaluate the number of roots, root canal morphology based on the Vertucci's classification, variations, and additional features such as accessory root canals, lateral canals, furcation canals, isthmus, and apical delta.

Results:

Nearly 52.88% of maxillary first premolars were single rooted, 44.88% had two roots, and 2.22% had three roots. Vertucci's Type IV root canal configuration was the most common type in maxillary first premolars and was seen in 66.51% of cases followed by Type II in 13.4%. Type I was seen in 9.76%, Type VI in 6.51%, Type VIII in 2.32%, Type III in 0.46%, Type V in 0.46%, and Type VII in 0% of teeth.

Conclusion:

The majority of the maxillary first premolars included in our study were single rooted and Vertucci's Type IV was the most common type of root canal configuration.

Cone-Beam Computed Tomographic Evaluation of Root Canal Morphology of Maxillary Premolars in a Saudi Population

Objective

The aim of the study was to investigate the root canal morphology of maxillary first and second premolars in a Saudi population using Cone-Beam Computed Tomography (CBCT).

Methods

This retrospective cross-sectional study assessed CBCT images of 707 Saudi patients. The number of roots and canal configuration were identified based on Vertucci's classification. Fisher's exact Chi-square tests were performed to analyze the association between sex and number of roots and sex and root canal configuration.

Results

Most teeth had two roots in maxillary first premolars (75.1%) and one root in maxillary second premolars (85.2%). Type IV was the most prevalent canal configuration in maxillary first premolars (69.1%), while Type I was the most in maxillary second premolars (49.4%). All types of canal configurations were observed in maxillary premolars except Type VII for the maxillary second premolar. Chi-square tests showed no significant association between gender and number of roots and sex and root canal configuration in both maxillary first and second premolars although higher number of roots was seen in men (P > 0.05).

Conclusion

Most maxillary first premolars had two roots with Type IV being the most predominant canal configuration, while a single root with Type I canal configuration was the most frequently observed morphology in maxillary second premolars. In maxillary first premolars, 21.3% had one canal apically, 75.4% had two canals apically, and 3.3% had three canals apically. In maxillary second premolars, 80.2% had one canal apically, 18.9% had two canals apically, and 0.9% had three canals apically.

Fracture resistance and stress distribution of repairing endodontically treated maxillary first premolars with severe non-carious cervical lesions

This study was to compare the influence of glass fiber post placement and crown restoration on endodontically treated maxillary first premolars with severe NCCLs using three-dimensional finite element analysis and fracture resistance testing. G1, intact teeth. G2, teeth with artificial defect. G3, composite resin (CR). G4, CR and fiber post in buccal canal (FPB). G5, CR and fiber post in palatal canal (FPP). G6, CR and fiber posts in buccal and palatal canals (FPBP). G7, CR and crown (C). G8, CR, FPB, C. G9, CR, FPP, C. G10, CR, FPBP, C. Teeth in G2, G3, and G5 showed a similar stress concentration at the tip of the defect. The fracture resistance of G2 did not differ significantly from G3 and G5 (p>0.05) but differed significantly from that in other groups (p<0.05). The fractures in G4 were more favorable, and the difference of those in G1 from those in G7, G8, G9, and G10 was statistically significant (p<0.05). Restoration of root-filled maxillary premolars with severe NCCLs using fiber post in the buccal canal may be more efficacious than other restoration methods.

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

OBJECTIVE

This 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.

DESIGN

774 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.

RESULTS

The 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.

CONCLUSION

The 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.

Atypical anatomy of maxillary second premolar with three roots and four canals

Knowledge and understanding the anatomical configuration of individual tooth play a significant role in success of endodontic treatment, in addition to through debridement and obturation of the canals. The canal anatomy of maxillary second premolar has been studied extensively, and the presence of a significant variety of multirooted canals is relatively rare in it. A 27-year-old female reported with a chief complaint of pain in her upper right posterior region for 10 days. On intraoral hard tissue examination, ill-defined access preparation was seen in maxillary right second premolar with exposed pulp. An intraoral periapical radiograph reveals radiolucency involving the pulp space and varied morphology in the same tooth. The occurrence of three roots with four canals in the maxillary second premolar is rare and not documented in the literature so far. This case report describes the nonsurgical endodontic management of such varied anatomical configuration using cone beam computed tomography as an evaluating diagnostic tool.

Diagnostic Accuracy of Periapical Radiography and Cone-beam Computed Tomography in Identifying Root Canal Configuration of Human Premolars

INTRODUCTION

The aim of this study was to assess the diagnostic accuracy of periapical radiography (PR) and cone-beam computed tomographic (CBCT) imaging in the detection of the root canal configuration (RCC) of human premolars.

METHODS

PR and CBCT imaging of 114 extracted human premolars were evaluated by 2 oral radiologists. RCC was recorded according to Vertucci's classification. Micro-computed tomographic imaging served as the gold standard to determine RCC. Accuracy, sensitivity, specificity, and predictive values were calculated. The Friedman test compared both PR and CBCT imaging with the gold standard.

RESULTS

CBCT imaging showed higher values for all diagnostic tests compared with PR. Accuracy was 0.55 and 0.89 for PR and CBCT imaging, respectively. There was no difference between CBCT imaging and the gold standard, whereas PR differed from both CBCT and micro-computed tomographic imaging (P < .0001). CBCT imaging was more accurate than PR for evaluating different types of RCC individually. Canal configuration types III, VII, and "other" were poorly identified on CBCT imaging with a detection accuracy of 50%, 0%, and 43%, respectively. With PR, all canal configurations except type I were poorly visible.

CONCLUSIONS

PR presented low performance in the detection of RCC in premolars, whereas CBCT imaging showed no difference compared with the gold standard. Canals with complex configurations were less identifiable using both imaging methods, especially PR.

Comparative evaluation of root canal morphology of mandibular premolars using clearing and cone beam computed tomography

Background:

Different techniques are used to evaluate the anatomy of root canal system. The present study was aimed to evaluate the root canal morphology of mandibular premolars using clearing and cone beam computed tomography (CBCT) techniques.

Materials and Methods:

A total of 182 mandibular first and second premolars were evaluated in vitro using 100 μm CBCT cross sections. The root canal morphology of the teeth was determined based on Vertucci classification in relation to the prevalence of C-shaped canals, lateral canals, and furcation location. Having removed the pulp tissue with NaOCl solution and staining the root canals with India ink, the samples were decalcified with 5% nitric acid and dehydrated with isopropyl alcohol. Finally, the samples were cleared with methyl salicylate. Data were analyzed by SPSS 16 software using McNamara, t-test, and Kappa coefficient.

Results:

After Type I, the most frequent morphologies in both first and second premolars were Type V followed by Type IV. The prevalence rates of C-shaped morphology in first premolars using clearing and CBCT were 4.4% and 6.6%, respectively. However, no C-shaped morphology was found in second premolars. The maximum and minimum levels of agreement between the two techniques were observed in Type IV and Type V root canal morphologies, respectively. Extra root canals were identified in 25% and 13% of the first and second premolars, respectively.

Conclusion:

CBCT showed a higher accuracy in determining C-shaped root canal morphology than the clearing technique. It also showed the least accuracy in diagnosing lateral root canals.

Buccally impacted maxillary canines increase the likelihood of root separation in adjacent first premolars

OBJECTIVE

To investigate the influence of maxillary impacted canines on the root morphology of adjacent premolars in a Chinese population.

SUBJECTS AND METHODS

A sample of 370 Chinese subjects with maxillary canine impaction and 370 control subjects were collected in this study. CBCT data of all subjects were collected and analyzed. The prevalence of separate-rooted maxillary premolars was compared between subjects with and without impacted canines. Then, the prevalence of separate-rooted maxillary premolars was compared between subjects with buccal canine impaction (BIC) and those with palatal impaction (PIC).

RESULTS

The prevalence of separate-rooted first premolars was significantly higher in the canine impaction group (P = 0.046), but the prevalence of separate-rooted second premolars was not different (P = 0.780). Furthermore, a significant higher prevalence of first premolar root separation was found on the impacted site in the BIC subgroup (P < 0.001), but not in the PIC subgroup (P = 0.508). Also, the prevalence of separate-rooted first premolars in the BIC subgroup was significantly higher than that of the control group (P = 0.008), but not so for the PIC subgroup (P = 0.097).

CONCLUSIONS

Buccally impacted maxillary canines are associated with an increased prevalence of root separation in the adjacent maxillary first premolars. This is likely because that buccally impacted canines encroach on the space needed for root development of the first premolars.

Age estimation based on pulp cavity/chamber volume of 13 types of tooth from cone beam computed tomography images

AIM

The aims of this study are to identify which type of tooth has the strong relationship between age and pulp cavity/chamber volume among 13 types of tooth from the same dentition and to determine whether the inclusion of multiple types of tooth may improve the accuracy of age estimation.

MATERIALS AND METHODS

Cone beam computed tomography (CBCT) images from 115 females and 125 males aged between 16 and 63 years were analyzed. The DICOM data of all the images were imported into ITK-SNAP 2.4 for the calculation of pulp cavity/chamber volumes. Logarithmic regression analysis and multiple linear regression analysis were applied to establish the relationship between age and pulp cavity/chamber volumes.

RESULTS

Among the 13 types of tooth, maxillary second molars have the largest R (2) (0.491, 0.642, and 0.498) and the smallest SEE (8.119, 6.754, and 8.022) in male, female, and pooled gender samples, respectively. The multiple linear regression analysis for the combination of multi-types of tooth indicated that a larger R (2) (0.627, 0.701, and 0.631) and smaller SEE (7.100, 6.258, and 6.970) than the counterpart calculated from the logarithmic regression analysis of a single type of tooth in male, female, and pooled gender samples, respectively.

CONCLUSION

The pulp chamber volume of the maxillary second molars has the largest correlation coefficient with age. Using multiple types of tooth may improve the accuracy of age estimation compared with only one type of tooth used.

Root Canal Morphology of Permanent Mandibular Premolars in Iranian Population: A Systematic Review

INTRODUCTION

It is essential for clinicians to have knowledge about root canal configuration, although its morphology varies largely in different ethnicities and even in different individuals within the same ethnic group. The current study reviewed the root canal configuration of root canals in mandibular first and second premolars among Iranian population based on independent epidemiological studies.

METHODS AND MATERIALS

A comprehensive search was conducted on retrieved articles related to root canal configuration and prevalence of each types of root canal in mandibular premolars based on Vertucci's classification. An electronic search was conducted in Medline, Scopus and Google Scholar from January 1984 to September 2015.

RESULTS

In eleven studies conducted in eight provinces, 1644 mandibular first premolars and 1268 second premolars were investigated. Within mandibular first premolars, 70.9% were Vertucci's type I, followed by 10.4% type III, 7.18% type IV, 5.23% type II and 5.16% type V. In addition, among mandibular second premolars, 82.86% were type I, 6.25 type III, 5.32% type II, 4.27% type IV, and 0.69% type V.

CONCLUSION

These results highlight the necessity of searching for additional possible root canals by clinicians. Moreover, these results indicated the ethnical characteristics of Iranian population regarding the morphology of mandibular premolars compared to other populations.

Root and Root Canal Morphology of Maxillary First Premolars: A Literature Review and Clinical Considerations

INTRODUCTION

Sound knowledge of the external and internal morphology of the different teeth groups is essential to ensure a successful outcome of root canal treatment. The aims of this study were to review the available literature with respect to the root and root canal morphology of maxillary first premolars and discuss the clinical considerations of this morphology on the various dental procedures.

METHODS

The MEDLINE/PubMed and Scopus databases were searched for relevant literature. The identified publications were classified into anatomic studies and clinical case reports. The data extracted from anatomic studies were tabulated, and weighted averages for certain internal and external morphologic features were calculated. The anatomic and developmental variations in the clinical case reports were summarized.

RESULTS

A total of 92 studies (45 anatomic studies and 47 case reports) including a total of 11,299 teeth were identified. The majority of maxillary first premolars had 1 root (41.7%) or 2 roots (56.6%). Regardless of the number of roots, the vast majority (86.6%) had 2 root canals, with type IV (2-2) being the most common canal configuration (64.8%). The majority of the apical foramina (66.6%) did not coincide with the apical root tip. About 38% of the teeth had lateral canals, 12.3% had apical deltas, and 16.0% had isthmi. The clinical case reports showed that the 3-rooted variant was the most common anatomic variation, and developmental anomalies were rarely reported.

CONCLUSIONS

The maxillary first premolars are predominantly 2-rooted teeth with 2 root canals. However, the clinician should be aware about the possible anatomic variations of these teeth and their relationship with the adjacent anatomic structures while planning and performing endodontic, restorative, periodontal, and surgical procedures.