Evaluation of the root and canal morphology of mandibular permanent molars in a south-eastern Turkish population using cone-beam computed tomography

Prevalence of middle mesial canal using cone beam computed tomography: A systematic review and meta-analysis

Background

The presence of middle mesial canals in mandibular molars are not commonly encountered in daily practice. However, locating and debriding such anatomical variation during the endodontic therapy is essential to avoid endodontic failure. The aim of this systematic review was to identify the overall prevalence of middle mesial canals (MMC) in mandibular molars using cone-beam computed tomography (CBCT), to assess the influence of different gender on the prevalence of MMCs in mandibular molars and to describe the MMC configurations.

Methods

The review protocol was registered in the PROSPERO database (CRD42021238523). The main electronic databases were searched until February 2022 for prevalence studies on root/canal anatomy in mandibular molars using CBCT imaging, in addition to hand-searched scientific articles in peer-reviewed journals and grey literature. The quality of the included studies was assessed using the Joanna Briggs Institute Critical Appraisal tool. Egger's and Begg's tests and Pearson's chi-square test were used for statistical analysis.

Results

From 523 records, 488 studies were excluded after screening the title and abstract. 35 relevant studies were included for full-text assessment and 28 studies were included in the meta-analysis. The overall prevalence of MMC out of the 19,256 teeth was 5.09% (95% CI: 2.894 to 7.784). The prevalence of MMC was 9.79% (95% CI: 4.296 to 17.224) in males and 13.96% (95% CI: 0.541 to 40.737) in females with a statistically significant difference of 4.16% (95% CI: 2.29 to 6.01). The most MMC configuration found in this review to be confluent with the mesiobuccal canal.

Conclusion

The results showed an overall 5.09% prevalence of MMC in mandibular molars, with a significantly high prevalence in female subjects. Additionally, this canal was found to be confluent with the mesiobuccal canal.

Root canal morphology of mandibular first molars: Comparison of the diagnostic accuracy of cone-beam computed tomography and the sectioning technique

Background

A successful endodontic treatment requires a comprehensive knowledge of the root canal morphology. This study compared the diagnostic accuracy of cone-beam computed tomography (CBCT) and the sectioning technique for the assessment of mandibular first molar (MFM) root canal morphology.

Materials and Methods

In this in vitro, experimental study, 48 eligible MFMs were mounted in 12 blocks (groups of 4) made of acrylic resin and sheep bone powder and underwent CBCT. Next, the teeth were mounted in transparent self-cure acrylic blocks, and their roots were sectioned at three points with 3 mm intervals. Images underwent multiplanar reconstruction in NNT Viewer software and were analyzed by one radiologist with the cooperation of an endodontist. The sections were also evaluated by an endodontist under a stereomicroscope (gold standard). The frequency and percentage of single-canal, and two-canal roots were determined by each technique. The agreement between CBCT and the Gold standard was analyzed by calculating the kappa coefficient (P < 0.05).

Results

The diagnostic accuracy of CBCT for the assessment of the MFM root canal morphology was 80% on the mesial surface, 99% in the distal surface, and 96% in total. In the mesial surface, 94.2% of two-canal roots and 66.7% of single-canal roots were correctly detected by CBCT. These values were 100% and 97.4% in the distal surface, and 95.2% and 95.8% in total, respectively. A significant agreement was noted between CBCT and the Gold standard with κ =0.412 for the mesial, 0.939 for the distal, and 0.907 for the total surfaces (P < 0.001).

Conclusion

CBCT can be reliably used for the assessment of the complex root canal morphology of MFMs when other modalities fall short.

The global prevalence of middle mesial canal in mandibular first and second molars assessed by cone beam computed tomography: A systematic review and meta-analysis

BACKGROUND

This meta-analysis sought to identify the in vivo prevalence and influencing factors of middle mesial canal (MMC) in mandibular first and second molars based on cone-beam computed tomography (CBCT) scans.

METHODS

MEDLINE/PubMed, Web of Science, Scopus, SciELO, Google Scholar databases/search engines were searched in period between 15^th and 21^st November 2022, to retrieve the in vivo CBCT-based studies that assessed the prevalence of MMC in mandibular first and/or second molars. The studies were strictly assessed using pre-defined inclusion and exclusion criteria for relevancy and eligibility through screening the title and abstract, and then assessed through reading the full texts using the same criteria. Subsequently, the fulfilled studies were assessed qualitatively using the Newcastle-Ottawa Quality Assessment Scale, and quantitatively using meta-analysis to calculate the pooled prevalence rates of MMC. The publication bias was assessed using funnel plot and Egger's test.

RESULTS

Out of 1,122 studies, 33 studies comprised 13,349 and 7,624 mandibular first and second molars, respectively, were eligible for inclusion. Twenty studies scored high quality, while thirteen scored moderate quality. The global prevalence of MMC in the first molar was 4.4% (95% CI = 0.035-0.053, P<0.001), significantly higher than that of the second molar which was 1.3% (95%, CI = 0.008-0.018, P<0.001). Gender, molar side, and age were not influencing factors of MMC prevalence.

CONCLUSION

The prevalence of MMC is not uncommon, being higher in the mandibular first molar compared to the mandibular second molar. The prevalence of MMC is not influenced by age, molar's side, and gender.

Evaluation of Root Canal Configuration of Maxillary and Mandibular First Molar by CBCT: A Retrospective Cross-Sectional Study

Adequate knowledge of root canal morphology along with its probable variations is imperative to acquire successful endodontic treatment. This retrospective cross-sectional study aimed to investigate the root canal configuration of maxillary and mandibular first molar using Cone-Beam Computed Tomography (CBCT) among patients in Al-Ahsa region, Saudi Arabia. A total of 377 samples were included, out of which 123 CBCT (I-CAT Vision QTM) scans with intact all first permanent molars were selected in this study and scanned in sagittal, axial, and coronal views by using BlueSkyPlan software. The number of canals in each root and their configuration according to the Vertucci classification system was evaluated. Statistical analysis was analyzed using SPSS version 21 (IBM). Chi-square test was applied to evaluate the association of root canal morphology and mandibular and maxillary first molars with respect to gender. Out of 123 CBCT scans, 59 (48.0%) were males and 64 (52.0%) were females; the mean age was 26.95 ± 10.65 years. The mesiobuccal root of bilateral maxillary first molar had Type-I (87.0%) of Vertucci classification followed by Type-IV (9.8%). Additionally, all mesiobuccal roots (100%) of the left mandibular first molar had Type-I of Vertucci’s classification. A significant association has been observed between gender and a number of canals in bilateral maxillary first molars. Females showed a significantly higher prevalence of three-root canal configuration in maxillary first molars of both sides compared four canals found most commonly in males (p = 0.004). This study concluded that the majority of maxillary and mandibular permanent first molars had three roots and three canals with Type-I Vertucci’s classification in patients belonging to the Al-Ahsa region of the Saudi Arabia. It was also proved that gender is significantly associated with the number of canals in a bilateral maxillary molar.

Variations of root and canal morphology of mandibular second molars in Chinese individuals: a cone-beam computed tomography study

BACKGROUND

The mandibular second molars demonstrate variations on root and canal morphology. The aim of this study was to investigate all the root canal morphology of mandibular second molars and analyze the morphological variations in patients by gender and age in a Chinese population use CBCT imaging.

METHODS

Cone-beam computed tomographic images of 1200 bilateral mandibular second molars were obtained from 600 patients (300 females and 300 males) who required a preoperative assessment for implant surgery, surgical removal of impacted teeth, orthodontic treatment, surgery of maxillofacial tumour and cysts or LeFort I osteotomy. CBCT images were divided into 5 groups according to age: "15-24 years", "25-34 years", "35-44 years", "45-54 years" and "≥ 55 years"; and 2 groups by gender: "females" and "males". The following information were recorded: the number of roots and canals and their morphology, the frequency and configuration of C-shaped canals by gender, age and position (left and right). The chi-square test was used to analyse differences between groups. P value of < 0.05 was considered statistically significant.

RESULTS

Of the 1200 teeth, 61% had two separate roots located mesiodistally, 35.6% had one C-shaped root. The 45.3% teeth had three canals in two-rooted mandibular second molars. The mesial root showed a Vertucci type II configuration in 28.9% cases followed by type IV(24.4%). While the distal root showed a significant higher prevalence of type I configuration in 95.6%. In the examined 1200 teeth, 430 teeth (35.8%) had C-shaped root canals. The prevalence of C-shaped root canal systems was significantly higher in females (42.5%) than in males (29.1%) (P = 0.000), and did not differ with age (P = 0.126). The 80.4% C-shaped canals were bilateral (P = 0.000) and did not differ with side (left and right) (P = 0.758).

CONCLUSIONS

The most commonly observed root morphology for the mandibular second molars was 2 separate roots with three canals.The prevalence of C-shaped root canal is 35.8% and is more higher in females than in males.

Three-Rooted Permanent Mandibular First Molars: A Meta-Analysis of Prevalence

Introduction

Although numerous amounts of high-level evidence were present, they solely emphasized the tooth-level prevalence of three-rooted permanent mandibular first molar. Global patient-level prevalence and bilateral symmetrical distribution of this type of teeth were needed to be tackled across the world. The research question was “What is the global prevalence of three-rooted permanent mandibular first molars?”

Materials and Methods

In vivo epidemiological studies undergone with Cone Beam Computed Tomography (CBCT) were eligible. The proportions of the prevalence of three-rooted permanent mandibular first molars were presented in the forest plots by random effect model. The calculation was performed with MetaXL version 5.3. Subgroup analysis, sensitivity analysis, and publication bias method were also calculated.

Results

Seventy-two studies from 31 countries were selected for both qualitative and quantitative analyses. 26302 patients and 37994 permanent mandibular first molars were included in the analysis. 9% of permanent mandibular first molars all over the world demonstrated 3 roots. These three-rooted teeth were found in 10% of the world population, more than 45% of which revealed bilateral symmetry of that anatomy. Right-side dominance and no sexual dimorphism were seen in the distribution of three-rooted permanent mandibular first molars. Global tooth-level prevalence of Radix Entomolaris and Radix Paramolaris was 12% and 0.1%, respectively.

Conclusion

The prevalence of three-rooted permanent mandibular first molars (PMFMs) was influenced by different geographical locations across the world and also by widespread habitation of the Mongoloid descent. The authors postulate that globalization, together with blending among ethnicities, may have a great impact on the reduction or accentuation of the anatomical significance in some populations.

Worldwide Assessment of the Mandibular First Molar Second Distal Root and Root Canal: A Cross-sectional Study with Meta-analysis

INTRODUCTION

This study assessed the prevalence of radix entomolaris and 2 canals at the distal aspect of mandibular first molars among different geographic regions by means of cone-beam computed tomographic imaging.

METHODS

Precalibrated observers from 23 worldwide geographic locations followed a standardized screening protocol to assess 5750 cone-beam computed tomographic images of mandibular first molars (250 per region), gathering demographic data and recording the presence of radix entomolaris and a second canal at the distal aspect of teeth. Intra- and interrater reliability tests were conducted and comparisons among groups were performed using proportions and odds ratio forest plots. The significance level was set at 5%.

RESULTS

The results of intra- and interrater tests were above 0.79. The prevalence of radix entomolaris varied from 0.9% in Venezuela (95% confidence interval [CI], 0%-1.9%) to 22.4% in China (95% CI, 17.2%-27.6%). Regarding the proportion of a second distal canal, it ranged from 16.4% in Venezuela (95% CI, 11.8%-21.0%) to 60.0% in Egypt (95% CI, 53.9%-66.1%). The East Asia subgroup was associated with a significantly higher prevalence of an extra distolingual root, whereas the American subgroup, the American native ethnic group, and elderly patients were linked to significantly lower percentages of a second canal at the distal aspect of teeth. No significant differences were noted between male or female patients.

CONCLUSIONS

The overall worldwide prevalence rates of radix entomolaris and a second canal at the distal aspect of the mandibular first molar were 5.6% and 36.9%, respectively. The East Asia geographic region and Asian ethnic group had a higher prevalence of a second distal root.

Prevalence of middle mesial canal and radix entomolaris of mandibular first permanent molars in a western Chinese population: an in vivo cone-beam computed tomographic study

Background

The aim of this study was to investigate the prevalence of the middle mesial canal (MMC) and radix entomolaris (RE) in mandibular first permanent molars in a western Chinese population using cone-beam computed tomography (CBCT).

Methods

A total of 1174 CBCT images of the mandibular first molars were collected from West China Hospital of Stomatology, Sichuan University. The following information was recorded and evaluated: the detection rate and location of the MMC and RE, the curvature of the RE, the canal configuration and bilateral symmetry.

Results

The detection rates of the MMC and RE were 3.41 and 25.04%, respectively, as calculated by individuals, and 1.79 and 22.15%, respectively, as calculated by total teeth. The average curvature in the buccolingual (BL) orientation (40.63 ± 14.39°) was significantly larger than that in the mesiodistal (MD) orientation (17.64 ± 7.82°) (p < 0.05). Of 587 patients, 71.72% (421/587) had bilateral symmetry according to the root canal morphology. The prevalence of three-rooted mandibular first molars was higher in males than in females, while the prevalence of two-rooted mandibular first molars was higher in females than in males.

Conclusions

Our results showed that the RE could be detected in almost 1/4 of the western Chinese population; thus, RE detection requires special attention and careful assessment in endodontic treatment.

A mandibular second molar with a middle mesial root canal

The present case report describes the clinical detection and root canal management of a rare middle mesial canal of a Japanese mandibular second molar by troughing preparation using an operating microscope and cone-beam computed tomography.

Cone-beam computed tomography investigation of middle mesial canals and isthmuses in mandibular first molars in a Chinese population

Background

While there is ample research into the anatomy of mandibular molars, little is known regarding isthmuses and middle mesial (MM) canals in Chinese populations. The goal of this study was to determine the prevalence of MM canals and isthmuses in the mesial root of mandibular first molars using Cone-beam Computed Tomography.

Methods

Cone-beam Computed Tomography images of 357 mature mandibular first molars were retrospectively analyzed. Presence of isthmuses and MM canals, and the length of isthmuses in the mesial root were recorded. Meanwhile, we also recorded possible correlated factors such as demographics, side of mandible, presence of separated distal-lingual roots.

Results

Of these 357 teeth, 209 showed evidence of either complete or partial communication in the mesial root. Of these, 11(3.1%) exhibited true MM canals while 198(55.5%) exhibited isthmuses. Sex or side of mandible was not correlated with the prevalence of isthmuses (P > 0.05). However, there was a significant association between the presence of a distal-lingual root and the prevalence of such communication (P < 0.001). The average length of isthmuses was 4.3 ± 3.1 mm.

Conclusions

We detected high rate of isthmuses and low rate of MM canals in mesial roots of mandibular first molars, which is important as such areas should be identified and cleaned during root canal treatment.

Root and Canal Configuration of Mandibular First Molars in a Yemeni Population: A Cone-beam Computed Tomography

Objective:

To describe root and canal morphology of mandibular first molars (MFMs) in a Yemeni population using cone-beam computed tomography (CBCT).

Methods:

CBCT images of 500 right and left untreated MFMs with fully developed roots from 250 Yemenis (125 male and 125 female) comprised the sample size of this study. The following characteristics were recorded: (1) number of roots and their type and morphology, (2) number of canals orifices per root, (3) type of canal configuration and (4) primary variations in the morphology of the root and canal systems.

Results:

96.8% of MFMs are double-rooted. A third root was found in 3.2%, more in females than males. Mesial root was mainly ribbon-shaped (92.2%) and distal root was kidney-shaped in 56.2%. Two canals orifices were found in mesial root of 95.8% and one canal orifice was found in distal root of 96.4%. Vertucci type II canal configuration was the most frequent (57%), followed by type IV (35.6%) in mesial root. Type III canal configuration was the most prevalent (48.8%), followed by type I (41%) in distal root. Variant 3 represented the most common root and canal morphology (89.8%).

Conclusion:

MFMs in Yemeni population are mainly two-rooted with 3.2% having a supernumerary distolingual root. Cross section of mesial root was mainly ribbon-shaped and distal root was kidney-shaped. Vertucci type II and III configurations were the higher incidence in mesial and distal roots, respectively. The presence of two canals in mesial root and one canal in distal root of MFMs with two separate roots (variant 3) was the most common morphology.

Prevalence of C-shaped mandibular molars in the Portuguese population evaluated by cone-beam computed tomography

Objective:

The purpose of this study was to evaluate the prevalence of first and second C-shaped mandibular molars in a Western European population of Portuguese Caucasians.

Materials and Methods:

Patients having both routine panoramic radiograph and presurgical cone-beam computed tomography (CBCT) exams were selected. The CBCT examination was performed at five different axial levels and the mandibular molars were classified as C-shape according to the Fan criteria. Differences between genders, age groups, left and right side, type of tooth, and root concavity side were determined. The molars were classified as nonfused roots (NFRI–II), FRI–III, or single root with single canal (SS) groups, using the panoramic radiograph. The prevalence of C-shaped anatomy was calculated to each group.

Results:

A total of 1783 teeth (695 first molars and 1088 second molars) from 792 patients were included in the study. The prevalence of C-shaped configurations was 0.6% and 8.5% to mandibular first and second molars, respectively. The differences between gender, teeth, and root concavity direction were considered statistically significant (P < 0.05). The FR had a significantly higher rate of C-shapes when compared to NFR (P < 0.05). Intrarater reliability was 93.6%.

Conclusions:

The FR radiographic appearance may be considered a predictor of this anatomy. Second mandibular molars and females had a higher incidence ratio. Apparently, the mandibular C-shaped anatomy is more common in the population of this study than that has been previously reported for the European population.

Evaluation of Root and Root Canal Morphology of Mandibular First and Second Molars in a Greek Population: A CBCT Study

Objective:

Τo study the number of roots, canal configurations, and frequency of morphological variations in mandibular first and second molars in a Greek population.

Methods:

This study examined 478 mandibular first molars and 524 mandibular second molars using a high-resolution cone-beam computed tomography (CBCT). The number of roots was recorded and the root canal configuration was categorized based on the classification by Vertucci. The presence and configuration of C-shaped root canals were recorded and they were classified according to the Fan classification. The symmetry between the right and the left side was also evaluated.

Results:

Among the mandibular first molars, 0.2% teeth were single-rooted, 96.4% were two-rooted, and 3.3% were three-rooted. In the mandibular second molars, 12.2%, 82.8%, and 4.9% were single-rooted, two-rooted, and three-rooted, respectively. In two-rooted mandibular first and second molars, the most frequent root canal pattern observed was Vertucci’s type II in the mesial root (69.8% and 64.1%, respectively) and Vertucci’s type I in the distal root (81.7% and 97.7%, respectively). Three-rooted molars showed one oval-shaped mesial root and two distal roots (56.2% in first molars, 65.4% in second molars), where each distal root contained a single root canal (type I), and the mesial root presented either type II (53.3%), IV (26.6%), I (13.3%), or V (6.6%) canal configurations. C-shaped canals were only detected in mandibular second molars (5.3% of teeth, 10.8% of individuals), and bilateral occurrence was observed in 24.5% patients. The most frequent root canal pattern was Fan’s C1 type at the orifice, followed by C3a and C3b in the coronal and middle third, which joined into a single canal (C4) apically.

Conclusion:

The characteristics of the root and root canal anatomy of the mandibular first and second molars of Greek individuals were similar to those observed in Caucasians. However, the higher incidence of third roots in mandibular molars in Greek individuals compared to Caucasians requires absolute clinical awareness.

Morphology of the Roots and Canals of Mandibular Third Molars, Their Symmetry and Related Factors Using Cone-Beam Computed Tomography

Introduction

Adequate knowledge about the anatomy of the roots and canals of mandibular third molars is imperative for a successful treatment. This study aimed to use cone-beam computed tomography (CBCT) to evaluate the morphology of the roots and canals of mandibular third molars and their symmetry.

Methods and Materials

Totally, 110 CBCT images of bilateral mandibular third molars were evaluated in terms of the number of roots and canals, canal type, isthmus location, location of accessory canals, degree of root curvature and its direction, age and sex of patients and the symmetry of variables in the right and left sides of the mandible. The descriptive statistics, t-test and chi-square test were applied to analyze data.

Results

Of all, 71.36% of mandibular third molars had two roots, 20.9% had one single root and 7.72% had three roots. The distal root had one single canal in 89.08%. The mesial root had one single canal in 44.25% and two canals in 49.42%. The Vertucci's types I (45.40%) and IV (34.48%) had the highest frequency in the mesial root while type I (91.95%) had the highest frequency in the distal root. The deviation of mesial root was towards the distal while distal roots were mainly straight.

Conclusion

The symmetry between the right and left mandibular third molars was significantly high. In case of encountering anatomical complexities in dental treatment of a mandibular third molar, dental clinicians should consider the high possibility of presence of the same condition in the contralateral mandibular third molar.

Study of Internal Morphology of Root-Canal Treated Single-Rooted Mandibular Second Molars in a Greek Population

Background/Aim: To determine the prevalence of single-rooted mandibular second molars in a Greek population and examine their internal morphology with the aid of intraoral periapical radiography.

Material and Methods: Clinical records of 531 root-canal treated permanent single-rooted mandibular second molars were collected from the Postgraduate Clinic of the Department of Endodontology, Dental School, Aristotle University of Thessaloniki, Greece and from private dental clinics in the same city. The clinical records, along with the radiographic examination, were evaluated to determine the overall frequency of single-rooted mandibular second molars together with the number of root canals and their course. The root canals were categorized using Vertucci’s classification with the addition of 3 further types where appropriate.

Results: Out of 531 mandibular second molars; 102 (19.2%) presented a single root; 427 (80.4%) presented two roots; 2 (0.4%) presented three roots. In a total of 102 single-rooted mandibular second molars 31 (30.3%) presented with Type I, 18 (17.6%) with Type II, 14 (13.7%) with Type IV, 7 (7%) with 3 additional root canal types and 32 (31.4%) with a C-shaped root canal system.

Conclusions: One out five mandibular second molars was single-rooted in a Greek population. The internal morphology of these teeth can be very complex with regard to the numbers and courses of root canals.

Cone-beam computed tomography analysis on root and canal morphology of mandibular first permanent molar among multiracial population in East Coast Malaysian population

Objective:

The aim of this study is to investigate the variations in the number of root and canal in the mandibular first permanent molars (MFPMs) teeth in East Coast Malaysian population using cone-beam computed tomography (CBCT).

Materials and Methods:

CBCT images which show MFPMs recorded in HUSM Dental Clinic between January 2015 and June 2016 was obtained and analyzed for their number of roots and canals. A total of 208 CBCT images of MFPMs were collected; 118 patients had unilateral molars and 90 patients had bilateral molars. The following observations were made: (1) root number; (2) number of canals per root; and (3) comparisons of number of roots and canals according to gender, ethnicity, and position.

Results:

The majority of cases of bilateral MFPM had the same number of roots (95.6%, 95% confidence interval [CI]: 89.01%, 98.78%) on both the right and left side and only 4 cases (4.4%, 95% CI: 1.22%, 10.99%) had 3 roots on the right and 2 roots on the left sides. The majority of cases had the same number of canals on both sides (66.7%, 95% CI: 55.95, 76.26%) and 33.3% (95% CI: 23.74%, 44.05%) with unequal number of canals. The occurrence of the number of canals was not independent of the sides of the arch (P < 0.001) and there was statistically significantly greater proportion of cases who had greater number of canals on the right side than the left (P = 0.03). The prevalence of right single-rooted MFPM was very small at 0.3% (n = 1) in a Malay male (95% CI: 0.00, 1.83) and the most prevalent was two roots first molar (88.4%). The number of roots was not associated with sex or ethnic group (P > 0.05). The MFPM with a single root was found to have only one mesial canal. For two rooted MFPM, the most prevalent occurrence was two canals at the mesial and one canal at the distal roots (59%); followed by single canals in each mesial and distal (21%) and double canals per root (18%). Three roots MFPM have either single or double canals in the mesial root and double canals in the distal root.

Conclusions:

The majority of population in the East Coast region of Malaysia has two roots and three root canals in their MFPMs. There was no difference in the number of roots between gender and ethnic and canals between ethnic.

Anatomy of Permanent‎ ‎Mandibular‎ First‎ Molars in a Selected Iranian Population Using ‎Cone-beam Computed Tomography

Introduction:

Knowledge of radicular anatomy has a crucial impact on endodontic practices. Since some anatomic features such as modifications of Vertucci are not evaluated adequately, this study was conducted.

Methods and Materials:

In this in vivo study, cone-beam computed tomography (CBCT) images of‎ 312‎ intact bilateral first‎ molars‎ from‎ 156‎ patients‎ (‎79‎ ‎males‎ and‎ 77‎ females with an average age of ‎35.58‎±‎11.17‎ years‎)‎ were‎ investigated by a trained dentist in terms of number‎ of‎ roots,‎ number‎ of‎ canals‎ in‎ each‎ root‎ and‎ in‎ ‎each‎ tooth,‎ and shapes‎ of‎ canals‎ according‎ to‎ Vertucci’s‎ classification‎ and‎ its‎ modifications.‎ Groups were compared using the Chi-square test. The level of significance was set at 0.05.

Results:

Of all teeth, 5.2%‎ had‎ 3‎ roots.‎‎ ‎Mesial‎ roots‎ had‎ mostly‎ 2‎ canals‎ while distal roots had a similar frequency of 1 and 2 canals.‎ ‎Of‎ all‎ teeth,‎ ‎‎39.7%‎ had‎ 3‎ canals,‎ 45.2%‎ had‎ 4‎ canals,‎ 13.8%‎ had‎ 5‎ canals,‎ and‎ 1.3%‎ had‎ 6‎ canals.‎ There were no significant differences between males and females, ‎in terms of number of roots (P=0.137), number of canals in mesial (P=0.453) or distal roots (P‎‎=0.328), and total number of canals (P=0.138).‎ The most frequent Vertucci classes in mesial and distal roots were IV ‎‎followed‎ by‎ II and I‎, respectively. There were no significant differences between males and females in terms of Vertucci classes of mesial (P=0.211) or distal (P=0.205) roots.

Conclusion:

In this population, there were 3 to 6 canals per tooth (mostly 4 and 3 canals).‎ Males and female’s ‎might be similar regarding the number of roots, or number of canals in each root, number of ‎canals in each tooth, or the predominant canal shape in each root.

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.

Prevalence of C-shaped canals in mandibular second and third molars in a central India population: A cone beam computed tomography analysis

Introduction

To evaluate the prevalence of C-shaped root canals in mandibular molars using cone beam computed tomography (CBCT) in a subpopulation of Central India.

Materials and Methods

CBCT scans of patients from diagnostic imaging center were selected in accordance with the criteria given by Fan et al. (2004) for C-shaped canals. A total of 238 CBCT scans fulfilled the inclusion criteria and thereby divided into two groups: Group 1: Images showing C-shaped canal configuration in mandibular second molars. Group 2: Images showing C-shaped canal configuration in mandibular third molars. The frequency and distribution of canals and their configuration along with the position of lingual/buccal grooves in the images were evaluated, and the data was analyzed.

Results

CBCT evaluation showed that 9.7% of second molars and 8% of third molars had C-shaped canals. A prominent buccal groove was seen in these teeth. The data showed a significant difference (P = 0.038) for the presence of such anatomy on the right side for mandibular third molars.

Conclusion

The study showed a significant prevalence of C-shaped canal configuration in the subpopulation studied.

Retrospective study of root canal configurations of maxillary third molars in Central India population using cone beam computed tomography Part- I

Objective:

The aim of this study was to investigate the root and canal morphology of maxillary third molars in Central India population using cone-beam computed tomography (CBCT) analysis.

Materials and Methods:

CBCT images of 116 maxillary third molars were observed, and data regarding the number of roots, the number of canals, and Vertucci's Classification in each root was statistically evaluated.

Results:

Majority of Maxillary third molars had three roots (55.2%) and three canals (37.9%). Most MB root (43.8%), DB root (87.5%), and palatal root (100%) of maxillary third molars had Vertucci Type I. Mesiobuccal root of three-rooted maxillary third molars had Vertucci Type I (43.8%) and Type IV (40.6%) configuration. Overall prevalence of C-shaped canals in maxillary third molars was 3.4%.

Conclusion:

There was a high prevalence of three-rooted maxillary molars with three canals.

Root canal anatomy of mandibular first premolars in an Emirati subpopulation: A laboratory study

Objective:

The purpose of this study was to determine the root canal anatomy of mandibular first premolar teeth in an Emirati subpopulation using a decalcification and clearing method.

Materials and Methods:

One hundred permanent mandibular first premolar teeth extracted for orthodontic purposes from an Emirati subpopulation from the United Arab Emirates were used for this study. They were subjected to decalcification and clearing. The tooth length, the canal orifice shape, mesial invagination, canal pattern, the location of apex, presence of lateral canals, and intercanal communications were determined.

Results:

The most common canal pattern was the Vertucci Type I (65%) followed by Type V (14%) and Type IV (13%). The most common type of canal orifice seen was the oval shape (36%) followed by the round shape (25%). Mesial invaginations were seen in 44% of the teeth. The mean tooth length was 19.9 mm, and apical deltas were seen in 24% of teeth.

Conclusion:

The Vertucci Type I canal pattern was the most prevalent in the mandibular first premolars while the occurrence of multiple canals was noted in 35% of this population.

Evaluation of root morphology and root canal configuration of premolars in the Turkish individuals using cone beam computed tomography

OBJECTIVE

The aim of the present study is to assess the root and root canal morphology of maxillary and mandibular premolars in a Turkish population by using cone beam computed tomography (CBCT).

MATERIALS AND METHODS

In this study, CBCT images of 2134 premolars (987 maxillary, 1147 mandibular) were obtained from 404 patients. Details of gender, age, number of roots and canals, and canal configuration in each root were recorded. The canal configuration was classified and evaluated according to Vertucci's criteria.

RESULTS

The majority of maxillary premolars had two separate roots; although, three roots were identified in 1% of maxillary first premolars. However, most of the mandibular premolars had a single root. The two canals (69.9%) and type I (62.6%) and type II (34.1%) configuration for upper first premolar, one canal (82.1%) and type I (77.6%) canal configuration for second premolar was the most prevalent root canal frequency. The most prevalent root canal frequency was the one canal (96.2%) and type I (94.2%) and type V (3.2%) configuration for mandibular first premolar, one canal (98.9%) and type I (98.9%) canal configuration for second premolar. There was no difference in the root canal configurations and the numbers of canals between the left and the right side of both females and males (P > 0.05).

CONCLUSIONS

Recognition of morphology and anatomy of the root canal system is one of the most important factors for successful endodontic treatment. Preoperative CBCT examination allows determination of root canal configuration of premolar teeth and helps clinicians in root canal treatment.

Rare Root Canal Configuration of Bilateral Maxillary Second Molar Using Cone-beam Computed Tomographic Scanning

The aim of this article was to present a right maxillary second molar with an unusual root canal morphology of 4 roots and 5 canals as confirmed by cone-beam computed tomographic (CBCT) imaging. The tooth had a C-shaped mesiobuccal root (CBCT imaging revealed that the root was closer to the palate than the buccal side) with 2 canals, 2 fused distobuccal roots with 2 separate canals, and 1 normal bulky palatal root with 1 canal. After thoroughly examining the rare anatomy, root canal treatment was applied on the tooth. This article shows the complexity of maxillary second molar variation and shows the significance of CBCT imaging in the confirmation of the 3-dimensional anatomy of teeth and endodontic treatment.

Cone-beam CT evaluation of root canal morphology of maxillary and mandibular premolars in a Turkish Cypriot population

Objectives:

Because of economic and political issues, Turkish Cypriots have been emigrating from Cyprus since the 1920s, especially to the United Kingdom, other European countries and Australia. Recently, according to the UK House of Commons, Home Affairs Committee, ~300,000 Cypriot Turks were living in the United Kingdom. However, this ethnic population residing in the United Kingdom has been insufficiently analysed. Although many Turkish Cypriots have been living abroad, little is known about the dental characteristics of this group. Premolar teeth, especially maxillary premolars, pose great challenges in endodontic treatment because of the number of roots and canals, and the variation in the configurations of the pulp cavity. Thus, it was considered valuable to determine the morphological characteristic of premolar teeth in a Turkish Cypriot population to aid clinicians in performing endodontic treatment in this ethnic population.

Materials and Methods:

The sample for this cross-sectional study consisted of a retrospective evaluation of cone-beam CT scans of 263 adult patients (age range 16–80 years). The number of roots and their morphology, the number of canals per root and the canal configuration were examined. The root canal configurations were also classified according to the scheme of Vertucci in the maxillary and mandibular premolar teeth. Pearson’s χ²-test was performed among canal configurations, sides and gender (P⩽0.05).

Results:

In the present study, most root canal configurations were type IV (76.8%) and type I (49.4%) in the maxillary first and second premolars, respectively, whereas most root canal configurations were type I (93%) in both mandibular first and second premolars. In total, four (0.9%) teeth in the maxillary first premolars and two (0.4%) teeth in the maxillary second molar premolars had three roots.

Conclusions:

This is the first population-based study to focus solely on Turkish Cypriots’ root canal anatomy. Our findings will be valuable for dental professionals who treat many Turkish Cypriot patients, in the United Kingdom, Australia and other countries.

The minimum residual root thickness after using ProTaper, RaCe and Gates-Glidden drills: A cone beam computerized tomography study

OBJECTIVE

The aim of this study was to evaluate the minimum residual root thickness (MRRT) of the danger zone after preflaring of the mesio-buccal (MB) canal of mandibular first molars using ProTaper, RaCe and Gates-Glidden (GG) drills as coronal shapers by cone beam computerized tomography (CBCT).

MATERIALS AND METHODS

In this experimental study, the initial CBCT scans of 75 MB canals of mandibular first molars were provided within 1, 2, 3 and 4 mm of the furcation level. The samples were divided into three groups. The samples of ProTaper and RaCe groups were prepared up to F2 and #25.04 as the master apical file (MAF), respectively. The coronal preparation of the samples in the GG group was done using GG drills #2, #3 and #4 and canals were prepared till MAF # 25. After obtaining the postinstrumentation images, the MRRT and the amount of removed dentin were analyzed by t-test and ANOVA statistical analyses.

RESULTS

The GG drills removed significantly more dentin than RaCe at all the sections (P < 0.05) and more than ProTaper at 3 mm from the furcation. Statistically there was no significant difference between ProTaper and RaCe groups (P > 0.05). There was no significant difference in MRRT between the groups (P > 0.05). The mean MRRT was not < 0.75 mm at all sections.

CONCLUSION

Based on the results of this study, when an appropriate root thickness is initially present, all of the instruments that were investigated may safely be used as coronal shapers in MB canals of mandibular first molars.

Comparative Analysis of Canal Centering Ability of Different Single File Systems Using Cone Beam Computed Tomography- An In-Vitro Study

BACKGROUND

The ability of an endodontic instrument to remain centered in the root canal system is one of the most important characteristic influencing the clinical performance of a particular file system. Thus, it is important to assess the canal centering ability of newly introduced single file systems before they can be considered a viable replacement of full-sequence rotary file systems.

AIM

The aim of the study was to compare the canal transportation, centering ability, and time taken for preparation of curved root canals after instrumentation with single file systems One Shape and Wave One, using cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

Sixty mesiobuccal canals of mandibular molars with an angle of curvature ranging from 20(o) to 35(o) were divided into three groups of 20 samples each: ProTaper PT (group I) - full-sequence rotary control group, OneShape OS (group II)- single file continuous rotation, WaveOne WO - single file reciprocal motion (group III). Pre instrumentation and post instrumentation three-dimensional CBCT images were obtained from root cross-sections at 3mm, 6mm and 9mm from the apex. Scanned images were then accessed to determine canal transportation and centering ability. The data collected were evaluated using one-way analysis of variance (ANOVA) with Tukey's honestly significant difference test.

RESULTS

It was observed that there were no differences in the magnitude of transportation between the rotary instruments (p >0.05) at both 3mm as well as 6mm from the apex. At 9 mm from the apex, Group I PT showed significantly higher mean canal transportation and lower centering ability (0.19±0.08 and 0.39±0.16), as compared to Group II OS (0.12±0.07 and 0.54±0.24) and Group III WO (0.13±0.06 and 0.55±0.18) while the differences between OS and WO were not statistically significant.

CONCLUSION

It was concluded that there was minor difference between the tested groups. Single file systems demonstrated average canal transportation and centering ability comparable to full sequence Protaper system in curved root canals.

Root canal morphology of South Asian Indian maxillary molar teeth

OBJECTIVE

The objective was to study the root canal morphology of South Asian Indian Maxillary molars using a tooth clearing technique.

MATERIALS AND METHODS

Hundred teeth each comprising of first, second, and third molars collected from different dental schools and clinics in India were subjected to standard dye penetration, decalcification and clearing procedure before being studied.

RESULTS

The first molar mesiobuccal roots exhibited 69% Type I, 24% Type II, 4% Type IV, 2% Type V, and 1% exhibited a Vertuccis Type VIII canal anatomy. In the group with three separate roots the second molar mesiobuccal roots in exhibited 80.6% Type I, 15.3% Type II, 2.7% Type IV, and 1.4% Type V canal anatomy while the third molars mesiobuccal roots exhibited 57.4% Type I, 32% Type II, 2.1% Type III, 8.5% Type IV, 1% had a Type V canal anatomy in the similar group.

CONCLUSION

A varied root canal anatomy was seen in the mesiobuccal root canal of the maxillary molars.

Endodontic treatment of a mandibular first molar with 8 canals: a case report

Presented here is a case where 8 canals were located in a mandibular first molar. A patient with continuing pain in mandibular left first molar even after completion of biomechanical preparation was referred by a dentist. Following basic laws of the pulp chamber floor anatomy, 8 canals were located in three steps with 4 canals in each root. In both of the roots, 4 separate canals commenced which joined into two canals and exited as two separate foramina. At 6 mon follow-up visit, the tooth was found to be asymptomatic and revealed normal radiographic periapical area. The case stresses on the fact that understanding the laws of pulp chamber anatomy and complying with them while attempting to locate additional canals can prevent missing canals.