Association between the Mesiobuccal Canal Configuration, Interorifice Distance, and the Corresponding Root Length of Permanent Maxillary First Molar Tooth: A Cone-beam Computed Tomographic Study

The Correlation between Intraorifice Distance and the Anatomical Characteristics of the Second Mesiobuccal Canal of Maxillary Molars: A CBCT Study

Introduction

Missing anatomy is one of the main causes of endodontic failures, and accurate knowledge of teeth anatomy is a prerequisite for adequate root canal treatment. The aim of the present cone beam computed tomography (CBCT) study was to describe the anatomical characteristics of the mesiobuccal (MB) root canals of maxillary molars and to understand if a correlation exists between the position of the canal orifices and the anatomical features of the root.

Methods

For the purposes of the study, a total of 100 CBCT scans of maxillary molars with two MB canals were selected and studied. The features of root canal anatomy of the MB root of the same teeth were analyzed and recorded (root length, confluence, and Vertucci classification). The distance between MB1 and MB2 orifices and the palatal orifice were recorded, as well as the distance between the orifices and the line joining the palatal orifice and the others. A statistical analysis was performed by providing descriptive measures, the measure of the correlation between different parameters, and the influence of some of these measures on the presence of a confluence between MB1 and MB2.

Results

It resulted that the most frequent configuration is type II Vertucci. The length measured on the sagittal plane was significantly correlated to the presence of a confluence in the MB root. When the root length was higher than 14.56 mm, the confluence is three times more frequent than when the length is lower (OR = 3.635). The area under the curve (AUC) of the receiver operator characteristic (ROC) curve for length on the sagittal plane was 0.632 (P=0.036).

Conclusions

The presence of a confluence between the MB canals of maxillary molars is correlated to the length of the root that could be measured on the sagittal plane and to the distance between the canal orifices. The relative position of the root canal orifices in relation to anatomic landmarks needs to be further explored.

Cone-Beam Computed Tomography Assessment of Prevalence of Procedural Errors in Maxillary Posterior Teeth

A range of procedural errors can occur when performing endodontic treatment on posterior teeth. These errors may decrease the success rate in endodontic practice. This study assessed the prevalence of procedural errors and the quality of endodontic treatments in maxillary molars and premolars using cone-beam computed tomography (CBCT). CBCT scans from two private radiology centers were assessed retrospectively to ensure the same calculated sample size of 327 teeth for each of the four maxillary posterior tooth types (a total of 1,308 endodontically treated teeth). Image sets were evaluated for procedural errors categorized as follows: obturation length (overfilling or underfilling by >2 mm short of the root apex), missed canals, perforations, strip perforations (with extrusion of material into the furcation area), separated instruments in the root canal space, and root fracture. Data were analyzed with SPSS version 20 (SPSS Inc., Chicago, IL, USA), and frequency data was assessed using the Monte Carlo test at the 0.05 level of significance. The procedural errors most commonly reported in the present study were from most frequent to least frequent: underfilled canals (50.0%), missed canals (27.5%), overfilled canals (12.5%), apical perforations (5.0%), separated instruments (3.1%), and root fractures (1.9%). No strip perforations (with extrusion of material into the furcation area) were seen in the study (0%). Underfilled and missed root canals were the most frequent procedural errors identified in the present study. These findings underline the importance of more consideration of critical working length management during all stages of root canal treatment, greater awareness of root canal anatomy, and the use of imaging and diagnostic devices that enhance the ability to identify and treat root canals both safely and effectively.

Morphometric relationships in mesio-buccal roots of maxillary first molars in Saudi subpopulation: A CBCT study

This CBCT-based study analysed morphometric relationships in Mesio-Buccal (MB) roots of maxillary first molars (MFM). 133 MFM with two MB canals were assessed and classified using Vertucci's classification. MB roots' length and MB1-MB2 canals inter-orifice distances (IOD) were noted. The data were analysed using SPSS software. The most frequently present canal was type IV (59.4%) followed by type II (40.6%). Mean MB roots' length for canals exhibiting type IV was 9.26 ± 0.21 mm and of those exhibiting type II was 12.8 ± 0.42 mm. Statistically significant relationship was found between MB root length and canal type. Mean IOD for type II and type IV canals was 2.4 ± 0.47 and 3.8 ± 0.21 mm, respectively. Statistically significant relationship was found between IOD and canal type. Length of MB root and IOD had a significant association with canal type present in MFM. This knowledge can enhance clinicians' understanding of canal morphology which can increase predictability and success rate of endodontic treatment.

Morphological analysis of anterior permanent dentition in a Chinese population using cone-beam computed tomography

PURPOSE

Morphological analysis of permanent anterior dentition is essential for achieving an ideal treatment outcome and avoiding unnecessary failure. This study aimed to analyze the morphologies of anterior teeth in the Chinese population in depth.

METHODS

In this retrospective study, 4309 anterior teeth from 401 Chinese patients were investigated using cone-beam computed tomography (CBCT) from 2019-2021. We summarized the morphological characteristics of the anterior teeth in terms of the root length, cementoenamel junction curvature (CEJ-C), root furcation and canal variations.

RESULTS

We found that the root lengths of the maxillary anterior incisors were similar (13.3 mm), while the root lengths of the mandibular central (12.2 mm) and lateral incisors (13.4 mm) varied significantly (p < .0001). Both the maxillary (16.6 mm) and mandibular canines (15.5 mm) were found to have greater root lengths than the corresponding incisors (p < .0001). The CEJ-C was significantly greater around incisors (2.5 mm) than around the canines (2.0 mm) in the maxilla (p < .0001), while the curvature remained similar in mandibular anterior teeth (1.8 mm). Root furcation was observed in mandibular canines and lateral incisors. Moreover, all types of Vertucci's classification in anterior dentitions were observed, while two other new types were found. Among them, the maxilla was only observed to exhibit types I, II, III, and ST II, while the mandible was found to exhibit almost all types. However, Type I still accounts for the majority of dentitions.

CONCLUSIONS

Morphological analysis of permanent anterior dentition revealed diversity in the tooth length, CEJ-C, furcation proportion, and canal variations. In general, mandibular anterior teeth showed a more complex structure than maxillary teeth.

Cone-beam computed tomography study of the incidence and characteristics of the second mesiobuccal canal in maxillary permanent molars

Objective: This study aimed to review the characteristics of the second mesiobuccal canal (MB2) in the maxillary first and second permanent molars of 500 patients to analyze the incidence of MB2 and its connection with gender, age, tooth position, and mesiobuccal (MB) root length. The study also aimed to investigate the distribution of the root canal orifice on the pulp chamber floor to obtain an imaging reference for clinical practices related to maxillary molars in Fujian, China. Methods: In accordance with the enrollment criteria, cone-beam computed tomography images of the maxillofacial area were collected from 500 patients, including 1,000 maxillary first molars and 1,000 maxillary second molars. The patients were grouped according to gender and tooth position. The incidence of MB2 was observed, and the MB root length and distribution angle of the mesiobuccal-palatal-distobuccal root canal orifices were measured for statistical analysis. Results: The overall incidence of MB2 in maxillary first and second molars was 51.1% and 32.9%, respectively. The incidence of MB2 in maxillary molars was 50% in male patients and 35.45% in female patients, with a significant difference (p < 0.05). The incidence of MB2 in maxillary molars was significantly higher in subjects aged below 50 (especially in male patients) than those aged 50 and above. The MB root length of maxillary first and second molars with MB2 was longer than that without MB2, and the difference was statistically significant. An association was identified between the incidences of MB2 in contralateral molars of the same type and in ipsilateral adjacent molars. When MB2 occurred in the MB root of maxillary molars, the root canals were mostly classified as type IV, followed by type II. The angle formed by the MB-P-DB orifices on the pulp chamber floor in the maxillary first and second molars was (25.23 ± 5.20) and (20.17 ± 10.88)°respectively. Conclusion: The incidence of MB2 in maxillary molars is high in Fujian, China. The occurrence of MB2 is affected by gender, age, and length of MB root, and it occurs symmetrically in adjacent molars and in contralateral molars of the same type. In addition, the distribution law of the main root canal orifice at the pulp chamber floor is conducive to locating MB2, thereby guiding clinical operations.

Assessment of the coronal root canal morphology of permanent maxillary first molars using digital 3D-reconstruction technology based on micro-computed tomography data

Background

The design of minimally invasive access has become a hotspot. This study aimed to evaluate the coronal root canal morphology of permanent maxillary first molars to facilitate the design of endodontic access cavities for minimally invasive linear access.

Materials and methods

A selection of 91 permanent maxillary first molars was evaluated. Three-dimensional tooth models were reconstructed using micro-computed tomography data. Root canal prevalence and coronal root canal landmarks were recorded. The positional coordinates of landmarks in the horizontal plane and the angles and directions of coronal root canal curvature in the horizontal and axial planes were also assessed.

Results

The detection rates of the mesiobuccal (MB), distobuccal (DB), and palatal (P) canals were 100%, whereas that of the second mesiobuccal (MB2) canals was 68.1%. All landmarks were located near the central fossa. In the axial plane, the average angles of coronal root canal curvature were DB (27.05°) > MB (25.43°) > P (20.71°) in teeth with three canals, and MB2 (33.20°) > MB (29.61°) > DB (28.40°) > P (23.69°) in teeth with four canals. In the horizontal plane, the average angles were P (78.15°) > DB (42.34°) > MB (32.41°) in teeth with three canals, and P (81.26°) > DB (43.44°) > MB (41.22°) > MB2 (9.41°) in teeth with four canals.

Conclusion

In maxillary first molars, coronal root canals tend to converge towards the occlusal surface. The results of this study could be applied to improve the precision of endodontic access cavity designs of minimally invasive access.

Association between second mesiobuccal canal and apical periodontitis in retrospective cone‐beam computed tomographic images

This retrospective cone-beam computed tomography study aimed to investigate the possible associations of apical periodontitis (AP) with missed/unmissed second mesiobuccal (MB2) canals. MB2 canals and AP were investigated in 257 endodontically treated and 673 untreated maxillary molars, and the former were analyzed regarding missed/unmissed MB2 canals. The chi-squared test and odds ratio (OR) were used for statistics. The prevalence of MB2 canals in maxillary first molars was higher than that in second molars (p = 0.001). MB2 canals were 1.751 times more common in males than in females (OR: 1.751; 95% CI: 1.334-2.297), with a significant difference in the 18-39 age groups (p = 0.005). The risk for AP was 5.5 times greater in endodontically treated maxillary molars with missed MB2 canals than in those with unmissed MB2 canals (p = 0.012) (OR: 5.5, 95% CI: 1.549-19.527). The findings of this study reveal that the likelihood of the MB2 canal is higher in the maxillary first molars of young adult males.

3D geometric analysis of second mesiobuccal canal in permanent maxillary first molar tooth

Cone-beam computed tomography scans exhibiting a second mesiobuccal (MB2) canal were examined. The vertical distance of the MB2 orifice from the pulp floor (depth), inter-orifice distance (IOD) of MB2 from mesiobuccal (MB) and palatal (P) orifices, the horizontal distance of the MB2 orifice from the line joining MB-P orifices [mesial deviation (MD)] and root canal configuration (RCC) were evaluated on 330 scans. The Student's t-test, ANOVA, Spearman's correlation and linear regression analysis were applied. The MB2 depth was 1.69 ± 0.86 mm. IOD (MB-MB2, MB2-P) was 2.18 ± 0.58 mm and 4.63 ± 1.06 mm, respectively. MD was 1.02 ± 0.37 mm. The predominant RCC was Vertucci's type II (75.5%). No correlation of depth with IOD of MB-MB2 (rho = 0.0367, p = 0.506) was observed. Significant correlation of depth with IOD of MB2-P (rho = 0.696, p < 0.001) and MD (rho = 0.174, p = 0.001) was established. No association of depth with age and IOD (MB-MB2) was observed on linear regression analysis. However, a significant positive association was established with IOD (MB2-P) (p < 0.001) and MD (p = 0.001).

Assessment of Mesiobuccal Canal Configuration, Prevalence and Inter-Orifice Distance at Different Root Thirds of Maxillary First Molars: A CBCT Study

Aim

The aims of this study were to assess the prevalence and configuration of the second mesiobuccal (MB2) canal in the mesiobuccal MB root of permanent maxillary first molars at different root levels in a Saudi sub-population using cone‑beam computed tomography (CBCT) and to measure the inter-orifice distance between MB & MB2 at the pulpal floor level.

Materials and Methods

This retrospective study was carried out on CBCT images of Saudi patients seen at King Abdul Aziz University. A total of 106 maxillary first molars were evaluated using a specialized software program (iCAT CBCT software). The prevalence of MB2, canal configuration and location of joining (apical-middle-coronal), if present was calculated. Also, the inter-orifice distance between both canals was measured at the level of the pulpal floor. Chi‑square and one-way analysis of variance (ANOVA) were used.

Results

The MB2 canal was found in 92 (86.8%) maxillary first molar teeth. The MB and MB2 canals were joined in 61 (58%) cases, where the location of joining was 14 (23%), 17 (27%), and 31 (50%) in the coronal, middle, and apical third, respectively. The mean inter-orifice distance between both canals at the level of the pulpal floor was 2.52±0.76 mm.

Conclusion

The prevalence of MB2 canal in this Saudi sub-population was high. The prevalence decreased as the root canal approached the apical third. There was no correlation between the average distance and occurrence of canal joining. CBCT is useful in detecting and mapping the mesiobuccal root canal system, with a likelihood of enhancing the quality of root canal treatment.

Mesiobuccal and Palatal Interorifice Distance May Predict the Presence of the Second Mesiobuccal Canal in Maxillary Second Molars with Fused Roots

INTRODUCTION

The aim of this study was to evaluate if the configuration of canal orifices can predict the presence of a second mesiobuccal canal (MB2) in maxillary second molars with fused roots.

METHODS

Maxillary second molars with fused roots (N = 150) were scanned in a micro-computed tomographic device (pixel size = 9 μm) and evaluated regarding the root fusion type and the incidence of the MB2 canal. The centers of the canal orifices were connected, and the angles formed by the intersection of these lines as well as their distances were measured and statistically compared (1-way analysis of variance). Specimens were then assigned to 2 groups according to the presence (n = 65) or absence (n = 50) of the MB2 canal and compared regarding the angles and interorifice distances using the Welch t test. A binary logistic regression model estimated the association between the interorifice distance, the fusion type, and the presence of the MB2 canal, whereas receiver operating characteristic curve analysis was performed to evaluate the diagnostic abilities of significant variables. The significance level was set at 5%.

RESULTS

The most common fusion types were 1 and 6, and MB2 canal incidence was 47.3%. No statistical difference was observed in the angles or interorifice distances among teeth with different fusion types (P > .05). Distances from the mesiobuccal (MB) to the distobuccal and palatal (P) canal orifices as well as the MB and P angles were significantly higher in the presence of an MB2 canal (P < .05). A binary logistic regression model revealed that MB-distobuccal and MB-P distances were significant in the presence of an MB2 canal (P < .05). Receiver operating characteristic analysis indicated that MB-P distance had acceptable diagnostic accuracy for the prediction of MB2 canal presence. Sensitivity (specificity) calculated from the MB-P distances of 4.0, 4.5, and 5.0 mm were 89.2% (36.5%), 76.9% (58.4%), and 44.4% (71.4%), respectively.

CONCLUSIONS

MB-P interorifice distance is a strong predictor of the presence of the MB2 canal in maxillary second molars with fused roots.