The MB3 canal in maxillary molars: a micro-CT study

A micro-computed tomographic evaluation of maxillary first molar root canal morphology in Black South Africans

PURPOSE

This study was conducted to investigate the root canal anatomy of maxillary first molars in Black South Africans.

METHODS

Micro-computed tomography was used to investigate 101 maxillary first molars (53 teeth from the right, 48 from the left; 50 male and 51 female teeth). The number of root canals in each tooth was determined, and the relationship between side, sex and age was analyzed using chi-squared test. To determine intra- and inter-observer reliability, Cohen's kappa coefficients were calculated.

RESULTS

Intra- and inter-rater agreements of 96.92% and 98.08% were achieved, respectively. Most teeth contained either three or four canals, but a second, third and fourth mesio-buccal canal was found in 60.39%, 5.94% and 0.99% of teeth, respectively. The disto-buccal and palatal roots contained predominantly single canals, but additional canals were noted in 2.97% and 1.98% of teeth. Four canals were common in females and teeth on the right side often contained a second mesio-buccal canal. However, the prevalence of a third mesio-buccal canal was higher in males than in females.

CONCLUSION

The teeth studied showed diversity and variations between sexes and arch sides. These findings will aid clinicians in endodontic treatment and will be applicable for educational purposes.

Clinical strategies for successful palato-mesiobuccal canal management-Report of 2 cases

AIM

To describe the management of the palato-mesiobuccal (PMB) canal in maxillary second molars with fused roots using conventional techniques.

SUMMARY

Root canal treatment success hinges upon effectively addressing the intricate and variable anatomy of molar teeth. Failure to do so can lead to persistent infections and treatment failure. Recent advancements in imaging technologies have provided unparalleled insights into dental anatomy, especially in molars. Among these discoveries is the PMB canal, a unique anatomical variant recently reported for the first time in Endodontic literature. This canal, found in maxillary second molars with fused roots and originating from the coronal third of the palatal canal while traversing towards the mesiobuccal root presents challenges in clinical management due to its location. This article is the first to showcase the management of the PMB canal using conventional techniques. In the first case, a 38-year-old male patient presented with asymptomatic irreversible pulpitis in the maxillary second right molar. Following thorough instrumentation and irrigation, the presence of the PMB canal was discovered during root canal preparation. The canal was managed using rotary instruments and obturated successfully, resulting in a symptom-free tooth at an 8-year follow-up. The second case illustrates a similar scenario in a 23-year-old female patient presenting with symptomatic irreversible pulpitis in tooth 17. The PMB canal was identified during treatment and managed using rotary nickel-titanium instruments, leading to a favourable outcome at a 9-year follow-up.

KEY LEARNING POINTS

In fused roots of maxillary second molars, a PMB canal might be expected. Exploration of the buccal wall of the palatal canal under magnification after shaping procedures can reveal the PMB canal orifice in fused roots. Small tapers are suggested for the enlargement of the PMB canal. Continuous bleeding spots in the palatal canal might indicate a possible PMB canal orifice in vital cases. The use of an apex locator is suggested for the differential diagnosis of the PMB canal orifice from a perforation site.

Endodontic Treatment of a Maxillary Second Molar With Five Canals: A Case Report and a Literature Review

A thorough understanding of both common and uncommon root canal anatomies is crucial for the success of root canal treatments, as missing a canal can lead to treatment failure. Although the maxillary second molar typically features three canals, the occurrence of five canals, particularly a mesial buccal third canal (MB3) canal in the mesiobuccal root, is extremely rare. This case report documents such a rare occurrence in a maxillary second molar with five canals. With the assistance of a dental operating microscope, all canals were successfully located, and root canal preparation, irrigation, and filling were accomplished. This case report underscores the significance of in-depth knowledge of root canal anatomy and the invaluable aid of a dental operating microscope in achieving successful root canal treatments.

Detection, characterisation and management of complex root canal configurations in the mesiobuccal roots of maxillary first molars: A case series

This report presents the detection, characterisation, instrumentation and filling of complex canal configurations in the mesiobuccal (MB) root of maxillary first molars. Three patients were referred for root canal treatment in first maxillary molars. Medical history, age, sex and clinical findings were recorded. Intraoral periapical radiographs and cone beam computed tomography (CBCT) were used for diagnosis and pre-operative assessment. Using Ahmed et al. (2017) classification system, codes 3MaxM MB3-5-4-2 DB1-2-1 P1 (case 1), 3MaxM MB2-5-3-2 DB1 P1 (case 2) and 3MaxM MB1-4-2-1-2 DB1 P1 (case 3) were identified. Using the dental operating microscope, CBCT (if indicated) and troughing up to 3 mm allowed identification of more than three canals in the MB root of maxillary first molars. The coding system proposed by Ahmed et al. (2017) allows the classification of MB roots with highly complex canal configurations.

Cone beam computed tomography analysis of the root and canal morphology of the maxillary second molars in a Hail province of the Saudi population

Background

The goal of the present research was to employ CBCT imaging to assess the root and canal anatomy of maxillary second molars in a population from the Hail province of Saudi. The effects of gender and side were taken into account.

Methods

The investigation included a sample size of 499 completely developed right and left untreated maxillary second molars obtained from 250 Saudi people. The root morphology of each tooth was evaluated. The examination also included an analysis of the canal morphology for each tooth, utilizing Vertucci's categorization. The effect of genders as well as sides was recorded. Results were analyzed using the Chi-square test.

Results

464 teeth had three roots (93.0%), whereas 20 teeth (4.0%) had two roots. One root was recorded in 7 (1.4%) of the study sample, whilst 8 (1.6%) had four roots. Although there were no significant differences between the left and right sides (p = .075), gender had a significant influence on the number of roots (p = .030). 240 M (48.1%) had three canal orifices, and 247 (49.5%) had four root canal orifices. Eight molars (1.6%) had two canal orifices, while one and five canal orifices were found in 3 (0.6%) and one (0.2%), respectively. Gender had a significant impact on the number of root canal orifices (p = .039). The observed differences in the orifices of the root canals between the left and right sides were not statistically significant (p = .059). The prevalence of MB2 in maxillary second molars was found to be 49.7%. In the mesiobuccal root, the Vertucci type I configuration had the highest canal frequency (50.3%), followed by the Vertucci types II (14.4%), IV (13.8%), V (12.0%), and III (7.6%), and VI (1.8%). The prevalence of Vertucci type I canal configurations was found to be higher in the distobuccal root (99.4%) and palatal root (98.2%) of maxillary second molars.

Conclusions

Significant variations in root canal anatomy were observed within the Saudi population. The majority of the subjects from Saudi Arabia in this study exhibited the presence of maxillary second molars with three roots. Approximately half of the sample under investigation exhibited the presence of the four canals.

Can the detection of second mesiobuccal canals be enhanced based on the volume of adjacent canals?

OBJECTIVES

The purpose of this study was to evaluate whether the presence of the second mesiobuccal (MB2) canal is related to volumetric differences on the adjacent canals of maxillary molars.

DESIGN

Forty-seven maxillary first and second molars with and without the MB2 canal were individually scanned using microcomputed tomography (micro-CT). The volume of each canal was measured by an evaluator with experience in micro-CT analysis. The intraclass correlation coefficient (ICC) was obtained. Multiple logistic regression and odds ratio was calculated. To compare the volume of canals in molars with and without MB2, the Mann-Whitney test was applied (α = 0.05).

RESULTS

The intra-examiner reproducibility was almost perfect (ICC=0.97). Multiple logistic regression demonstrated that the volume of the mesiobuccal (MB1) canal can possibly act as a predictor of the presence of the MB2 canal. It was also found that the MB1 canal volume is larger in molars without the MB2 canal (p = 0.01). No statistically significant difference was observed in the adjacent canals (p > 0.05).

CONCLUSIONS

Despite the challenging detection of the presence of MB2 canals, clinicians should be aware that MB1 canals of reduced volume are highly suggestive of their presence.

FEATURES OF THE VARIATIVE MORPHOLOGY OF THE MANDIBULAR SECOND MOLAR USING CONE-BEAM COMPUTED TOMOGRAPHY IMAGING

OBJECTIVE

The aim: To characterize the variations in the anatomical structure of the second lower molar.

PATIENTS AND METHODS

Materials and methods: In order to determine the topography of the roots and root canals of the mandibular second molar, modern imaging methods were used: orthopan¬tomography and cone-beam computed tomography.

RESULTS

Case report: During the analysis of the orthopantomogram of the patient, the three-root morphology of the root system of 37 teeth was revealed. That is, three roots were clearly visualized. After detecting an atypical shape of the root system of the mandibular second molar in the panoramic image, the patient was offered to perform cone-beam computed tomography (CPCT) for diagnostic purposes. Analysis by cone-beam computed tomography showed the presence of four mature roots of normal length, which were arranged in the shape of a diamond.

CONCLUSION

Conclusions: The four-root configuration is considered a rare form for mandibular molars, but it should be considered in endodontic interventions and, if possible, in the planning of such interventions, use cone-beam computed tomography.

Micro-CT assessment of radicular pulp calcifications in extracted maxillary first molar teeth

OBJECTIVES

The present study aimed to evaluate the frequency, position, and length of radicular pulp calcifications in three-rooted maxillary first molars using micro-computed tomography.

MATERIALS AND METHODS

Two hundred three-rooted maxillary first molars were scanned at a pixel size of 10 µm and reconstructed using similar parameters. Three-dimensional models of the mesiobuccal (MB1, MB2, MB3), distobuccal (DB), and palatal (P) canals were qualitatively evaluated for discontinuity in the canal path. Transaxial and sagittal cross-sectional images of the roots were further screened, and the complete obliteration of the canal lumen by pulp calcification was identified when the canal had similar radiodensity to the surrounding dentine. Then, the number, position, and length of the calcifications were recorded for each root. Intra-observer agreement was performed using Cohen's kappa test, while one-way ANOVA and Duncan tests compared the lengths of calcifications among the canals, with α = 5%.

RESULTS

Intra-observer agreement was perfect for identification of pulp calcifications (ĸ = 1.0; p = 0.000). MB2 and MB3 canals accounted for the highest percentage frequency of calcifications distributed throughout the canal path. In the MB1, DB, and P canals, they occurred mainly at the apical third. Lengths of calcifications were greater in the MB3 (0.89 ± 0.81 mm) and MB2 (0.82 ± 0.93 mm) canals than in the MB1 (0.39 ± 0.32 mm), DB (0.34 ± 0.22 mm), and P (0.28 ± 0.22 mm) canals (p < 0.05).

CONCLUSION

MB2 and MB3 canals accounted for the highest frequency and length of radicular pulp calcifications. In the MB1, DB, and P canals, calcifications occurred mostly at the apical third, while in the MB2 and MB3, most of calcifications were observed at the orifice level and along the canal path.

CLINICAL RELEVANCE

In maxillary first molars, radicular pulp calcifications are mainly located at the apical third of the MB1, DB, and P canals, while in the MB2 and MB3 canals, most of them are at the orifice level or along the canal path.

Automated segmentation and description of the internal morphology of human permanent teeth by means of micro-CT

High-resolution micro-computed tomography is a powerful tool to analyze and visualize the internal morphology of human permanent teeth. It is increasingly used for investigation of epidemiological questions to provide the dentist with the necessary information required for successful endodontic treatment. The aim of the present paper was to propose an image processing method to automate parts of the work needed to fully describe the internal morphology of human permanent teeth. One hundred and four human teeth were scanned on a high-resolution micro-CT scanner using an automatic specimen changer. Python code in a Jupyter notebook was used to verify and process the scans, prepare the datasets for description of the internal morphology and to measure the apical region of the tooth. The presented method offers an easy, non-destructive, rapid and efficient approach to scan, check and preview tomographic datasets of a large number of teeth. It is a helpful tool for the detailed description and characterization of the internal morphology of human permanent teeth using automated segmentation by means of micro-CT with full reproducibility and high standardization.