The potential applications of cone beam computed tomography in the management of endodontic problems

Topographic Evaluation of Inflammatory Periapical Lesions in the First Molar's Region Using CBCT

Background: Investigating the pattern of extension in the periapical (PA) inflammatory lesions is important in the treatment plan and prognosis of treatment. Introduction: This study evaluated the topography of PA inflammatory lesions in the first molars using cone-beam computed tomography (CBCT). Methods: In this descriptive study, 197 CBCT images about patients in the age group of 14-77 years were analyzed. The maximum extension of the PA lesion in the three orthogonal planes related to the regions of maxillary and mandibular first molars was measured and reported in millimeters. Measurements were compared based on age, gender, dental arch, and root type. Statistical analysis was performed using percentages, repeated measure ANOVA, paired t-tests, and Pearson correlation coefficient. The significant level was set at 0.05. Results: The highest total mean lesion extensions were in the vertical plane followed by the buccolingual and mesiodistal plane. There was a statistically significant difference between the extension of the PA lesion in the vertical and mesiodistal (p < 0.001), vertical and buccolingual (p =0.001), as well as the mesiodistal and buccolingual planes (p =0.027). In the maxilla and mandible, the highest mean lesion extension was in the vertical, buccolingual, and mesiodistal plane, respectively. According to the root type, there was only a statistically significant difference in lesion extension in the buccolingual plane and between the mesial and distobuccal roots (p =0.030). Conclusion: Given the limitations of the present study, regarding the extension of the PA lesion in the first molar region, the bone structure of the maxilla and mandible follows a precise and delicate pattern. In this regard, future studies in different communities and races should be designed to address this issue in different communities. In addition, CBCT is a reliable imaging method to evaluate the extension of the PA lesion both morphologically and morphometrically.

Evaluation of root and root canal morphology of mandibular and maxillary canine teeth in Turkish subpopulation by cone beam computed tomography with using two classification systems

BACKGROUND

Knowledge of root and canal morphology is a prerequisite for effective nonsurgical and surgical endodontic treatments. The aim of this cone beam computed tomography (CBCT) study was to evaluate the root canal morphology of permanent canines in a Turkish subpopulation using two classification systems.

METHODS

A total of 2,000 canine teeth were examined. The number of roots was identified, and root canal configurations were classified according to Vertucci's classification and a new system for classifying root and canal morphology. Fisher's exact test was used for statistical analysis, and the level of significance was set at 0.05 (p = 0.05).

RESULTS

The canal configuration type I was the most common in all canines, while type III was the second most common. According to the new system, the code 1C1-1 was the most common, whilst 1C1 (A1) codes were the second most common for all canines. In this study, more than 10% morphology that did not fit the Vertucci classification was detected. In the categorization of accessory canals based on the new classification, the most common type in all canines was 1C1,1 (A1). Age had an effect only on the morphology of the left maxillary canine (p < 0.05).

CONCLUSION

Canines in the Turkish subpopulation showed a relatively high degree of variation in root and canal anatomical variations. Clinicians should be aware of where canals converge or diverge to avoid missing canals. The new system for classifying canal morphology describes root and canal configurations more accurately and practically compared to the Vertucci classification.

Stress distribution in restored mandibular molars with external cervical resorption: a finite element analysis

This study evaluates the stress distribution in mandibular molar teeth with external cervical resorption restored using various restorative and biomimetic materials through finite element analysis. A mandibular first molar was scanned to create a 3D model. 'Class 2Bp' external cervical resorption defects were simulated on the buccal aspect and restored with different materials. Composite resin or highly viscous glass ionomer cement restored the coronal portion, while mineral-trioxide-aggregate, Biodentine, BioAggregate, or glass-ionomer cement filled the radicular portion. Models representing unrestored external cervical resorption and intact teeth were also created. Access cavities were restored with composite resin in all models except the intact tooth model. This computational simulation study used finite element analysis (ANSYS) to assess stress distribution in mandibular molars with external cervical resorption. A 300 N oblique force, directed buccally at a 45° angle, was applied to simulate masticatory forces, and von Mises stresses were evaluated in the resorption regions to compare materials' performance in terms of stress concentration and tooth integrity. Similar stress distributions were observed when restoring the coronal portion with composite resin or highly-viscous glass ionomer cement. Stress decreased with mineral-trioxide-aggregate or glass-ionomer cement in the radicular portion compared to Biodentine and BioAggregate. Restored and intact tooth models experienced lower stresses than unrestored tooth. All tested models were considered safe, except the unrestored external cervical resorption model. Restored external cervical resorption models are generally safe; however, using mineral-trioxide-aggregate or glass-ionomer cement in the radicular portion may slightly reduce stress in external cervical resorption regions.

The use of 0.5% or 3% NaOCl for irrigation during root canal treatment results in similar clinical outcome: A 6-year follow-up of a quasi-randomized clinical trial

AIM

To evaluate the 6-year outcome of root canal treatment irrigated with 0.5% or 3% sodium hypochlorite (NaOCl).

METHODOLOGY

The baseline trial was designed as a quasi-randomized clinical trial. Patients referred for root canal treatment to an endodontic specialist clinic were recruited to the study (n = 298). The concentration of NaOCl was allocated quasi-randomized to 271 subjects (0.5% [n = 139], 3% [n = 132]). Bacterial sampling was performed immediately before root canal filling. Samples were cultured and evaluated as growth or no growth. Patients were invited to a clinical and radiological follow-up >5 years postoperatively. The clinical outcome measurements were tooth survival, cumulative incidence of endodontic retreatments, patients' assessment of pain, clinical findings and radiological signs of apical periodontitis (AP).

RESULTS

Tooth survival was 85.6% in the 0.5% NaOCl group and 81.1% in the 3% NaOCl group (p = .45). There was no record of retreatment in 94.4% in the 0.5% NaOCl group and in 92.2% in the 3% NaOCl group (p = .76). The percentage of asymptomatic cases were 87.8% in the 0.5% group and 85.3% in the 3% NaOCl group (p = .81). Absence of clinical signs of AP was seen in 86.6% in the 0.5% NaOCl group and in 83.6% in the 3% NaOCl group (p = .80). Absence of radiological signs of AP was seen in 74.0% in the 0.5% NaOCl group and 64.1% in the 3% NaOCl group (p = .20). Subjects with positive culture before root filling reported subjective pain with a significantly higher frequency as compared to negative-culture subjects (p = .014).

CONCLUSIONS

The use of 0.5% or 3% NaOCl for irrigation during root canal treatment resulted in similar clinical outcomes 5-7 years postoperatively. Persisting bacteria immediately before root filling may predict future episodes of subjective pain.

Conservative Management of Invasive Cervical Resorption: A Case Report

"Invasive cervical resorption" (ICR) is a disorder that impacts the region of root surface that is present below the level of attachment of epithelium. Clinically, it manifests as a pink stain on the cervical part of the tooth. It may be due to visualization of the densely vascularized granular tissue across the resorbed structure of the tooth. The invasive defect should be made visible, the granulation tissue should be removed, and the defect should be sealed using a variety of restorative materials. In this report, a patient who presented with trauma related Class II ICR in the cervical region of the left second premolar of the maxilla was treated conservatively. It was shown that patients who are reluctant to undergo surgery or in whom surgery is not recommended could be treated with this conservative approach to stop the advancement of ICR.

In Vitro Research Methods Used to Evaluate Shaping Ability of Rotary Endodontic Files-A Literature Review

BACKGROUND/OBJECTIVES

In this article, we present a literature review of methods used to measure the shaping ability of endodontic rotary files, including the selection of endodontic sample type (extracted teeth versus simulated blocks) and an imaging evaluation method. This review was conducted as background research to identify concerns that arise when designing research studies in this domain and propose how the field can plan more systematic studies going forward.

METHODS

A literature search was conducted using PubMed, MEDLINE, Embase, ScienceDirect, Scopus, and e B-on databases, including studies published in English from January 2010 to June 2024. Only studies that specified in vitro or ex vivo methods for evaluating the endodontic performance of NiTi rotary files on canal transportation and centering ability were considered.

RESULTS

A total of 86 studies met the inclusion criteria from an initial pool of 651. Of these, 67 studies used extracted teeth, while 20 utilized simulated root canals in resin blocks. For evaluation methods, 55 studies employed Micro-Computed Tomography and Cone-Beam Computed Tomography (MCT + CBCT), 30 used Double Digital Images/Radiographs/Photographs (DDIR + DDIP) with software analysis, 1 used both DDIR and MCT, 1 used high-precision nano-CT, and 1 used a digital single-lens reflex (DSLR) camera.

CONCLUSIONS

The findings indicate that the MCT method and its advanced variations appear superior in many cases for evaluating the quality of root canal instrumentation due to their ability to provide detailed three-dimensional images. We also discuss the pros and cons of other evaluation methods, including CBCT and DDIR. Finally, we identify important factors to consider for optimizing future cross-study comparisons. This work highlights the importance of being familiar with shaping ability assessment methods as new instruments are introduced to the market.

Comparative evaluation of the accuracy of electronic apex locators and cone-beam computed tomography in detection of root canal perforation and working length during endodontic retreatment

BACKGROUND

To evaluate the accuracy of the electronic apex locators (EALs), and Cone-Beam Computed Tomography (CBCT) scanning, both in working length (WL) determination and in the detection of root canal perforations in retreatment cases.

METHODS

Sixty human mandibular premolars were selected. After crown removal partially and canal access, root canals were instrumented and irrigated. The obturation process utilized gutta-percha and sealer with warm vertical compaction. Two groups were distinguished: one without perforation (Group 1) and the other with an apical third perforation (Group 2). Retreatment included filling removal, apical preparation, and irrigation. Actual working lengths (AWL) were determined using a stereomicroscope. CBCT images were used to measure CBCT working length (CWL), with adjustments for optimal views. Propex II and Dentaport ZX were used to measure electronic working length (EWL). Differences between EWL and AWL, as well as CWL, were analyzed to gauge accuracy. Data underwent Two-way ANOVA analysis. Measurements within ± 0.5 and ± 1 mm tolerance ranges were deemed successful for each device, followed by applying the Pearson Chi-square test.

RESULTS

The study reveals no significant inter-group variations in device performance (p > .05). Dentaport ZX missed detecting perforation in two Group 2 (apical perforation) cases. For ± 1 mm tolerance, Propex II displayed the highest success in Group 2 (apical perforation).

CONCLUSION

This study demonstrates the comparable performance of Propex II, Dentaport ZX, and CBCT in endodontic retreatment, providing insights into diagnostic reliability.

Is a Pre-Existent Cone-Beam Computed Tomography Able to Detect Metal Dental Posts?

(1) Background: In this study, the efficacy of cone-beam computed tomography (CBCT) in detecting dental posts was compared to periapical radiography. (2) Methods: A retrospective evaluation of 53 patients' periapical radiographs and CBCT images was performed. The presence and type of the intra-canal dental post were initially determined on the periapical images (PA) radiographs' examination and were then compared to the observer's ability to detect the dental post on a CBCT image. The effect of the post's type (metal cast or prefabricated) on its detection on CBCT images was determined. (3) Results: 10.5% of teeth that were identified as having a post on a PA radiograph were not identified as having a post on the CBCT examination (p < 0.05). Approximately 17.6% of teeth that were identified as not having a post on a PA radiograph were identified as having a post on the CBCT examination (p < 0.05). Moreover, 16.3% and 50% of teeth with a prefabricated or cast posts on PA radiographs were falsely identified on the CBCT examination, respectively (p < 0.05). (4) Conclusions: A CBCT image is an insufficient tool for the identification of metal prefabricated and cast posts. A PA image is the recommended radiographic tool for achieving information about the post-endodontic restoration status of teeth candidates for endodontic retreatment in patients with a former CBCT scan.

Endodontic Treatment Outcomes in Cone Beam Computed Tomography Images-Assessment of the Diagnostic Accuracy of AI

Background/Objectives: The aim of this study was to assess the diagnostic accuracy of the AI-driven platform Diagnocat for evaluating endodontic treatment outcomes using cone beam computed tomography (CBCT) images. Methods: A total of 55 consecutive patients (15 males and 40 females, aged 12-70 years) referred for CBCT imaging were included. CBCT images were analyzed using Diagnocat's AI platform, which assessed parameters such as the probability of filling, adequate obturation, adequate density, overfilling, voids in filling, short filling, and root canal number. The images were also evaluated by two experienced human readers. Diagnostic accuracy metrics (accuracy, precision, recall, and F1 score) were assessed and compared to the readers' consensus, which served as the reference standard. Results: The AI platform demonstrated high diagnostic accuracy for most parameters, with perfect scores for the probability of filling (accuracy, precision, recall, F1 = 100%). Adequate obturation showed moderate performance (accuracy = 84.1%, precision = 66.7%, recall = 92.3%, and F1 = 77.4%). Adequate density (accuracy = 95.5%, precision, recall, and F1 = 97.2%), overfilling (accuracy = 95.5%, precision = 86.7%, recall = 100%, and F1 = 92.9%), and short fillings (accuracy = 95.5%, precision = 100%, recall = 86.7%, and F1 = 92.9%) also exhibited strong performance. The performance of AI for voids in filling detection (accuracy = 88.6%, precision = 88.9%, recall = 66.7%, and F1 = 76.2%) highlighted areas for improvement. Conclusions: The AI platform Diagnocat showed high diagnostic accuracy in evaluating endodontic treatment outcomes using CBCT images, indicating its potential as a valuable tool in dental radiology.

Long-Term Trends in the Utilization of Cone Beam Computed Tomography in Oral and Maxillofacial Radiology

Background

Cone beam computed tomography (CBCT) has become a cornerstone in oral and maxillofacial radiology due to its high-resolution, three-dimensional imaging capabilities and lower radiation exposure compared to traditional computed tomography (CT). The purpose of this retrospective study is to examine long-term patterns in the use of CBCT in a tertiary care context, with an emphasis on patient characteristics, CBCT indications, and variations in use patterns over time.

Methods

During the course of 5 years, a tertiary care facility performed 500 CBCT scans, all of which were included in the study. Information on the age, sex, and source of referral for each patient was gathered from their electronic medical records. Radiology data were used to categorize CBCT indications, which included implant planning, impacted tooth assessment, and pathology evaluation. Regression analysis and descriptive statistics were used to examine utilization trends.

Results

Throughout the study period, there was a consistent rise in the use of CBCT, with implant planning being the most often cited indication. Impacted tooth assessment and pathology evaluation were next in line. Considerable differences were noted in the use of CBCT for various age groups and indications. The results demonstrate how CBCT is improving oral and maxillofacial radiology's diagnostic precision and treatment planning. In summary, this study offers a significant understanding of the long-term patterns in CBCT use in a tertiary care context. With ramifications for resource allocation, patient care, and future research objectives, the observed trends highlight the increasing acceptability and incorporation of CBCT into standard clinical practice.

Management of rarely seen internal tunnelling root resorption associated with a maxillary permanent incisor

This case presents clinical techniques and materials that may be applied in the management of internal tunnelling root resorption, a rare condition which has little published literature.A 25-year-old woman was referred to a specialist centre by her general dental practitioner following an incidental finding of a radiographic radiolucency, suggestive of root resorption associated with tooth 21. A provisional diagnosis of external cervical resorption was made, and following cone beam computed tomography (CBCT), a definitive diagnosis of internal tunnelling root resorption given. Non-surgical endodontic treatment was completed using continuous wave compaction with a calcium-silicate based sealer. No further intervention has been required.A summary of the histology, aetiology, prevalence, diagnosis, management and prognosis of internal tunnelling root resorption is provided. The benefits of CBCT for diagnosing and managing internal tunnelling resorption defects and using continuous wave compaction with a calcium-silicate based sealer, compared to cold obturation techniques, are discussed.

Clinically Oriented CBCT Periapical Lesion Evaluation via 3D CNN Algorithm

Apical periodontitis (AP) is one of the most prevalent disorders in dentistry. However, it can be underdiagnosed in asymptomatic patients. In addition, the perioperative evaluation of 3-dimensional (3D) lesion volume is of great clinical relevance, but the required slice-by-slice manual delineation method is time- and labor-intensive. Here, for quickly and accurately detecting and segmenting periapical lesions (PALs) associated with AP on cone beam computed tomography (CBCT) images, we proposed and geographically validated a novel 3D deep convolutional neural network algorithm, named PAL-Net. On the internal 5-fold cross-validation set, our PAL-Net achieved an area under the receiver operating characteristic curve (AUC) of 0.98. The algorithm also improved the diagnostic performance of dentists with varying levels of experience, as evidenced by their enhanced average AUC values (junior dentists: 0.89-0.94; senior dentists: 0.91-0.93), and significantly reduced the diagnostic time (junior dentists: 69.3 min faster; senior dentists: 32.4 min faster). Moreover, our PAL-Net achieved an average Dice similarity coefficient over 0.87 (0.85-0.88), which is superior or comparable to that of other existing state-of-the-art PAL segmentation algorithms. Furthermore, we validated the generalizability of the PAL-Net system using multiple external data sets from Central, East, and North China, showing that our PAL-Net has strong robustness. Our PAL-Net can help improve the diagnostic performance and speed of dentists working from CBCT images, provide clinically relevant volume information to dentists, and can potentially be applied in dental clinics, especially without expert-level dentists or radiologists.

Effects of different treatment modalities on biomechanical behavior of maxillary incisors with external invasive cervical resorption at different progression levels

BACKGROUND/AIM

This study aimed to evaluate the biomechanical behavior of maxillary incisors with external invasive cervical resorption (EICR) at different progression levels after receiving different modes of treatment under occlusal forces using finite element analysis (FEA).

MATERIALS AND METHODS

Three-dimensional (3D) models of intact maxillary central incisors were constructed and modified to include EICR cavities with different progression levels in the buccal cervical areas. The EICR cavities confined to dentin were repaired using Biodentine™ (Septodont Ltd., Saint Maur des Fausse ́s, France), resin composite, or glass ionomer cement (GIC) . Additionally, EICR cavities with pulp invasion requiring direct pulp capping were simulated as repaired using Biodentine only or 1 mm thick Biodentine and either resin composite or GIC for the rest of the cavity. Moreover, models with root canal treatment and EICR defects repaired using Biodentine, resin composites, or GIC were also generated. A force of 240 N was applied to the incisal edge. The principal stresses in the dentin were evaluated.

RESULTS

GIC showed more favorable results than the other materials in EICR cavities confined to the dentin. However, Biodentine alone resulted in more favorable minimum principal stresses (Pmin ) compared to other materials in EICR cavities with close pulp proximity. Exceptionally, the models localized in the coronal third of the root with a circumferential extension of the cavity >90° showed more favorable results for GIC. The presence of root canal treatment had no significant effect on stress values.

CONCLUSIONS

Based on this FEA study the use of GIC in EICR lesions confined to the dentin is recommended. However, Biodentine may be a better option for restoring EICR lesions close to the pulp with or without root canal treatment. Except when the circumferential extension of the cavity is >90°, the use of GIC may be more advantageous.

Diagnosis of Odontogenic Maxillary Sinusitis by Cone-beam Computed Tomography: A Critical Review

INTRODUCTION

This review aims to provide an up-to-date overview of the current applications of cone-beam computed tomography (CBCT) and other imaging modalities in diagnosing odontogenic maxillary sinusitis (OMS). Furthermore, the clinical operation procedures of radiography modalities in OMS diagnosis were summarized, with the goal of assisting clinicians in improving OMS diagnostic accuracy in clinical practice.

METHOD

A comprehensive review of researches that discussed the applications of radiography modalities in the diagnosis of OMS was conducted. Pertinent information was evaluated and organized for this review.

RESULTS

Cone-beam computed tomography (CBCT) offers a superior, high-resolution, and three-dimensional view of the maxillary tooth-bone-sinus complex compared to conventional radiography modalities. It enables a better understanding and classification of the spatial relationships between root apices/periapical lesions and maxillary sinus. The use of CBCT, combined with the advantages of other radiography modalities and proper image interpretation, is indispensable to enhance OMS diagnostic accuracy and mitigate the risk of missed or misdiagnosis.

CONCLUSION

The significance of CBCT in the diagnosis of oral and maxillofacial conditions has garnered widespread recognition. It provides highly precise diagnostic information and classification basis for OMS. The clinical operation procedures for imaging examination are essential in ensuring the consistency and reliability of the diagnosis.

Endodontic Orthograde Retreatments: Challenges and Solutions

Endodontic orthograde retreatments are considered one of the possible treatment options in case of post-treatment diseases considering the promising results present in the literature. Despite this, a plethora of articles have been published on this topic, and drawing conclusions could be challenging. For this reason, this review aims to summarize the crucial points on each aspect of non-surgical endodontic retreatments, discussing and comparing the current protocols, techniques, materials, and indications. Taking into consideration data from the literature, in terms of diagnosis, CBCT should be considered the first choice, since it can thoroughly affect the diagnosis and treatment plan. Regarding the procedural phases, some conclusions can be drawn: when present, coronal restoration materials such as crowns, partial prostheses, post, and core should be removed; the use of magnification devices, ultrasonic instruments, and an in-depth interpretation of radiographic images with both 2D and 3D images are strongly recommended during the orifice location; additional protocols such as irrigants activation, ultrasonic cleaning, and rotary or reciprocating instrumentation of treated canals are strongly recommended for filling materials removal and to achieve a high-quality chemo-mechanical disinfection; perforations should be treated as soon as possible, and the material of choice to treat them is the MTA or other calcium-silicate-based repair materials; the presence of ledges does not intrinsically reduce the success rate of RCRts if properly managed; in case of instrument fragments, their removal should be considered as the first treatment option, however many variables should be considered to select the proper technique or consider the option of bypassing.

Ex vivo detection of mandibular incisors' root canal morphology using cone-beam computed tomography with 4 different voxel sizes and micro-computed tomography

BACKGROUND

In recent years, cone-beam computed tomography (CBCT) has been widely used to evaluate patients' root canal anatomy due to its high resolution and noninvasive nature. As voxel size is one of the most important parameters affecting CBCT image quality, the current study evaluated the diagnostic potential of CBCT with 4 different voxel sizes in the detection of double root canal systems and accessory canals (ACs) in permanent mandibular incisors.

METHODS

A total of 106 extracted mandibular permanent incisors were collected from the dental clinics, and then were scanned by using micro-CT with a voxel size of 9 μm. The teeth were then fixed in the tooth sockets of human dry mandibles and scanned by using a CBCT device with 4 different voxel sizes (300, 200, 250, and 125 μm). Four observers detected in blind the root canal morphology of the teeth according to the CBCT images, and the presence or absence of a double root canal system, and the presence or absence of ACs, were scored according to a 5-point scale, respectively. Receiver operating characteristic (ROC) analysis was performed, and DeLong test was used to compare the area under the curve (AUC) values and the micro-CT data was taken as a gold standard.

RESULTS

Among 106 sample teeth, 25 specimens with a double root canal system were identified by the micro-CT. ROC curve analysis of the data obtained by the four observers showed that in the detection of double root canal systems, the AUC values ranged from 0.765 to 0.889 for 300 μm voxel size, from 0.877 to 0.926 for 250 μm voxel size, from 0.893 to 0.967 for 200 μm voxel size, and from 0.914 to 0.967 for 125 μm voxel size (all p < 0.01). In general, we observed a trend that the AUC values, sensitivity, and specialty increased with the decrease in the voxel size, and significantly higher AUC values were detected in 125 μm voxel size images. In the detection of ACs, ROC curve analysis showed that among the four observers, the AUC values ranged from 0.554 to 0.639 for 300 μm voxel size, from 0.532 to 0.654 for 250 μm voxel size, from 0.567 to 0.626 for 200 μm voxel size, and from 0.638 to 0.678 for 125 μm voxel size. CBCT images at a voxel size of 125 μm had a weak diagnostic potential (AUC: 0.5-0.7, all p < 0.05) in the detection of AC, with a lower sensitivity ranging from 36.8 to 57.9% and a higher specialty ranging from 73.6 to 98.8%.

CONCLUSIONS

CBCT with 300 μm voxel size could only provide moderate diagnostic accuracy in the detection of a double canal system in mandibular incisors. CBCT with a voxel size of 125 μm exhibited high diagnostic value in the detection of double canal systems, while showing low but statistically significant value in the detection of ACs.

Is There a Relationship Between Maxillary Sinus's Inferior Pneumatisation and Sinonasal Variations? A Retrospective CBCT Study

Objectives

This retrospective study aims to analyse alveolar and palatal process pneumatisation and their relationships with sinonasal variations using cone-beam computed tomography.

Material and Methods

The study included 500 patients aged 18 to 87 years, involving 1000 maxillary sinuses with cone-beam computed tomography scans. We examined the relationship between inferior maxillary pneumatisation and the following anatomic variations: Haller cell, concha bullosa, paradoxical concha, bifid concha, and septal deviation.

Results

Among the 1000 maxillary sinuses assessed, we found 223 (22.3%) with alveolar process pneumatisation (APP), 37 (3.7%) with palatal process pneumatisation (PPP), and 23 (2.3%) with the presence of both APP and PPP. Significant relationships were observed between the Haller cell (P = 0.005), nasal septum deviation (P = 0.000), and middle concha bullosa (P = 0.01) with APP. However, there were no significant relationships between the paradoxical middle concha (P = 0.07), bifid middle concha (P = 0.74), and APP. Similarly, significant relationships were observed between the Haller cell (P = 0.001), paradoxical middle concha (P = 0.009), bifid middle concha (P = 0.000), and PPP. However, there were no significant relationships between concha bullosa (P = 0.799) and PPP. Additionally, we found significant relationships between the Haller cell (P = 0.003) and the presence of both APP and PPP.

Conclusions

This study provides an anatomical basis for imaging diagnosis by investigating the frequency of inferior pneumatisation of the maxillary sinus and its relationship with certain sinonasal variations.

Cone-Beam Computed Tomography Assessment of Quality of Endodontic Treatment and Prevalence of Procedural Errors in Mandibular Molars

Objectives

This study assessed the quality of endodontic treatment and the prevalence of procedural errors in permanent mandibular molars using cone-beam computed tomography (CBCT).

Materials and Methods

This cross-sectional study was conducted on 328 CBCT scans (182 females and 146 males) of endodontically treated mandibular molars retrieved from the archives of two radiology centers in Ardabil city, Iran, in 2019. Mandibular molars were evaluated on sagittal, coronal, and axial sections regarding obturation length, obturation density (voids), missed canals, broken instruments, apical perforation, strip perforation, ledge formation, transportation, root fracture, root resorption, and periapical lesions by a senior dental student under the supervision of an oral and maxillofacial radiologist and an endodontist. Differences between the frequency of procedural errors and tooth type and gender were analyzed by the chi-square test.

Results

The frequency of underfilling, missed canals, overfilling, voids, apical perforation, transportation, ledge formation, broken instruments, root fracture, strip perforation, root resorption, and periapical lesions was 34.8%, 17.4%, 16.8%, 14.3%, 7.3%, 6.1%, 4.3%, 3%, 1.2%, 0.6%, 5.5%, and 46%, respectively. The frequency of root fracture was significantly higher in females than in males (P < 0.05). The prevalence of underfilling was the highest in right second molars (47.2%), followed by right first molars, left second molars, and left first molars (P < 0.005). The frequency of transportation was maximum in right first molars (10%), followed by right second molars, left first molars, and left second molars (P < 0.04).

Conclusion

Underfilling, missed canals, and overfilling were the most prevalent procedural errors in mandibular molars in our study population.

Introduction of Accurate Measurement of the Alveolar Bone Height in Bone Grafting Area after Sinus Lift

BACKGROUND

Sinus lift via the alveolar crest approach has been proven to solve inadequate alveolar bone height perfectly in the posterior region of the maxilla. Nevertheless, the surgical area cannot be directly observed, imaging methods are necessary to reveal whether the surgery has achieved the expected results. Cone-Beam Computed Tomography (CBCT) images are usually taken before surgery and at the completion of final pre-repair osseointegration and evaluate the effect of maxillary sinus lift by measuring the alveolar bone height in the bone graft area. However, there is no uniform and recognized method to accurately measure the alveolar bone height in the bone grafting area before and after maxillary sinus lift. Therefore, the authors propose a simple, accurate, and reproducible method for the measurement of alveolar bone height in maxillary sinus lift on CBCT, which will be an innovation.

METHODS

30 implant cases (30 patients) were included in this study. The authors create a uniformed measurement surface in the CBCT axial interface to ensure consistency at the completion of final prerepair osseointegration and before surgery. Then changes in alveolar bone height in the bone grafting area before and after sinus lift were measured on CBCT coronal and arch planes. Finally, for the purpose of verification of repeatability, three dentists from our department were randomly selected to measure and record the above CBCT data at three different time points.

RESULTS

The data showed that in the CBCT measurements of the three dentists, neither the coronal plane nor the arch plane was statistically significant. (P > 0.05).

CONCLUSION

This measurement method is simple, accurate and repeatable. It can be applied to measure alveolar bone height in the bone grafting area before and after maxillary sinus lift.

Assessment of the Proximity of the Inferior Alveolar Canal with the Mandibular Root Apices and Cortical Plates-A Retrospective Cone Beam Computed Tomographic Analysis

Various endodontic interventions often lead to iatrogenic damage to the inferior alveolar nerve present in the inferior alveolar canal (IAC). The purpose of the present study was to analyze the relationships of IAC with the root apices of mandibular teeth and with the mandibular cortical plates.

MATERIALS

116 cone beam computed tomography (CBCT) scans were examined and the shortest distance of IAC with the root apices of mandibular canines, premolars and molars, and with cortical plates was analyzed. The data were statistically analyzed using SPSS.

RESULTS

The shortest mean distance between IAC and lingual cortical plate (LCP) was found in the third molar area, and between IAC and buccal cortical plate (BCP) in the second premolar area. A high incidence of 60% direct communication (DC) was present in mandibular second molars; 38% in mandibular third molars; 13% in mandibular second premolars; 12% in mandibular first molars; and 1% in mandibular first premolars.

CONCLUSION

Anteriorly, IAC was found to be significantly present in close approximation to the roots of mandibular canines. Posteriorly, IAC was found to be in significant proximity to the distal roots of mandibular second molars.

Conservative Therapy of External Invasive Cervical Resorption with Adhesive Systems: A 6-Year Follow-Up Case Report and Literature Review

The diagnosis and treatment of external invasive cervical resorption (EICR) could be a challenging clinical situation even for the most experienced dentists. It is a fairly rare lesion and a poorly understood phenomenon, and its insidious and aggressive nature can lead to tooth loss. Even in the era of dental implants, trying to save a compromised tooth is imperative for any clinician. This report presents a case of an upper central incisor with a class II Heithersay EICR in which treatment was performed using a multidisciplinary approach and the defect was restored with resin composite. The surgery in which the defect was exposed and repaired was followed by an endodontic treatment and the placement of a fiber-reinforced post. In this case, the use of modern materials, such as resin composites, allowed not only the avoidance of tooth extraction but also the achievement of satisfactory aesthetic results. The 6-year follow-up demonstrated the success of therapy and the resolution of clinical symptoms. This case report highlights the importance of early detection of EICR and how composite resins could provide an effective and aesthetic restauration of the defect, which favors the health of the surrounding gingival tissue.

In Vitro Diagnostic Accuracy and Agreement of Dental Microscope and Cone-Beam Computed Tomography in Comparison with Microcomputed Tomography for Detection of the Second Mesiobuccal Canal of Maxillary First Molars

OBJECTIVES

The percentage of failure of endodontically treated maxillary molars is relatively high; one main reason is that the second mesiobuccal canal (MB2) is missing. Some techniques have been proposed for detection of the MB2. This study was aimed at assessing the diagnostic accuracy and agreement of the dental microscope and cone-beam computed tomography (CBCT) in comparison with microcomputed tomography (micro-CT) for detection of the MB2 of maxillary first molars in vitro.

MATERIALS AND METHODS

This in vitro, experimental study evaluated 71 permanent maxillary first molars that were stored in 100% humidity at room temperature. The teeth were mounted in 9 silicone dental arches to the level of their cementoenamel junction (8 teeth in each arch). The blocks underwent CBCT in a XG3D scanner. Access cavity was then prepared, and the teeth were inspected by a surgical microscope for negotiation of the MB2. Also, micro-CT images were obtained from the teeth to serve as the gold standard. CBCT and micro-CT images were observed by two examiners twice with a 2-week interval.

RESULTS

The frequency of the MB2 detected by dental microscope was significantly lower than micro-CT (P < 0.001) and CBCT (P = 0.008); no significant difference existed between micro-CT and CBCT in this respect. The sensitivity, specificity, positive predictive value, and negative predictive value of CBCT for detection of MB2 were 92.6%, 100%, 100%, and 81%, respectively.

CONCLUSION

CBCT is superior to the dental microscope for detection of the MB2 of maxillary first molars and can be used for this purpose in the clinical setting with adequate accuracy.

Comparison of Fracture Resistance of Endodontically Treated Teeth With Traditional Endodontic Access Cavity, Conservative Endodontic Access Cavity, Truss Endodontic Access Cavity, and Ninja Endodontic Access Cavity Designs: An In Vitro Study

Introduction: Endodontic access cavity preparation plays a vital role as preservation of enamel structure is of utmost importance for a tooth's strength to be maintained. As teeth become fragile after a root canal therapy, this study was designed to compare in vitro the fracture resistance of root-filled and restored teeth with traditional endodontic access cavity, conservative endodontic access cavity (CEC), ninja endodontic access cavity (NEC), and truss endodontic access cavity (TEC).

Materials and methods: Control (intact teeth) and traditional endodontic access cavity as well as CEC, NEC, and TEC groups were each given a new human mandibular molar that was freshly removed. Cone beam computed tomography (CBCT) scans of the cone beam showed the values of CEC, NEC, and TEC. After that the teeth were endodontically treated and repaired. To test the specimens, universal testing equipment was used. In order to avoid tooth breakage, the maximum load was determined. Statistical analysis was used in the form of Kolmogorov-Smirnov and Levene tests, which were used to examine data for typical dispersion and consistency in change.

Results: Intact teeth showed the highest resistance to fracture compared with other groups. TEC showed significantly higher resistance to fracture compared to the CEC design.

Conclusions: It is possible, within the restrictions of this research, to infer that the TEC design enhanced tooth fracture strength in comparison with the CEC design.

Role of HRCT Temporal Bone in Predicting Surgical Difficulties Encountered in Fenestral Otosclerosis Surgery

To study spectrum of high resolution computed tomography (HRCT) imaging findings in otosclerosis, to predict approximate length of prosthesis required from pre-operative HRCT measurements and to correlate between oval window niche (OWN) height preoperatively and difficulty in introducing foot plate perforator during surgery. A cross sectional study was conducted on 23 patients with a clinical diagnosis of otosclerosis from September 2018 to July 2020. Sensitivity of HRCT in detecting otosclerosis, correlation between pre-operative incudo-stapedial length (ISL) and intra operative prosthesis length, and correlation between OWN height and difficulty in introducing perforator were sought. The mean age of 23 patients studied was 39.9 years with a female preponderance of 56.5%. 17 out of 19 patients with foci of otosclerosis during surgery had HRCT findings of otosclerosis providing a sensitivity of 89.5%. Mean OWN height obtained was 1.29 mm preoperatively and a cut off value of 1.325 mm found using receiver operating characteristic curve method classifying OWN height as narrow or normal. Mean ISL measured pre operatively was 4.25 mm and mean length of prosthesis used was 4.56 mm with significant positive correlation using intraclass correlation coefficient method with correlation coefficient = 0.879. HRCT is an invaluable modality aiding the surgeon to detect otosclerotic foci with high sensitivity, identify thick obliterative otosclerotic foci requiring additional drilling, to predict the length of prosthesis used and to predict difficulties in approaching footplate when OWN height is below 1.325 mm.

The C-shaped Canal System in Mandibular Molars of a Saudi Arabian Population: Prevalence and Root Canal Configurations Using Cone-Beam Computed Tomography

OBJECTIVES

This retrospective study aimed to assess the prevalence of the C-shaped canal system in mandibular first and second molars in a Saudi Arabian population using cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

The sample included 300 CBCT images from adults aged 18 to 80 years (38.7 ± 17.9) (150 females and 150 males). All images were analyzed to detect the C-shaped root canal according to Fan's criteria. We also categorized our findings according to the gender and direction of the longitudinal groove. Data were reported as frequencies and percentages. The Chi-squared test was used to analyze proportional differences, with the significance level set at ≤0.05.

RESULTS

The C-shaped canals were observed in 146 mandibular first molars (24.33%) and 182 second molars (30.33%). Male patients had a significantly higher prevalence of C-shaped canals in mandibular second molars than females (P=0.003). The longitudinal groove was most typically detected on the root's lingual surface (53.35%).

CONCLUSION

The incidence of the C-shaped canal in a Saudi Arabian population was 27.33% in the mandibular molars. The longitudinal groove was mostly on the lingual surface. Males showed a higher prevalence of the C-shaped canal than females.

Management of periapical lesion with persistent exsudate

Resumo Este relato de caso descreve o tratamento e acompanhamento de um molar inferior em uma jovem de 18 anos com cisto periapical. Assim, torna-se importante saber quais opções devemos tomar diante de uma situação clínica que não podemos resolver pelos métodos convencionais, e quais técnicas e abordagens temos para alcançar o sucesso do tratamento. Este caso mostrou o plano de tratamento e acompanhamento, por meio de imagens de tomografia computadorizada de feixe cônico (TCFC), de um molar inferior previamente tratado com grande abscesso periapical e lesão cística, no qual, a primeira abordagem do plano de tratamento foi fazer o retratamento endodôntico. Durante o preparo químico-mecânico a presença de exsudato purulento intracanal permanente impossibilitou a secagem dos canais, impedindo a obturação do sistema de canais radiculares. Devido a essa situação clínica, foi realizada abordagem cirúrgica com a intenção de reduzir esse exsudato permanente e executar uma técnica de descompressão. Após um ano de acompanhamento, os achados clínicos e radiográficos indicaram processo de reparo.

Root canal morphologies of mandibular premolars in Southeast Anatolian population: Evaluation of CBCT

Background/Aim: This study aimed to evaluate the root canal morphology of mandibular first and second premolars with the aid of cone-beam computed tomography (CBCT) in the Southeast Anatolian population. Material and Methods: The study examined a total of 1258 mandibular first and second premolars using cone-beam computed tomography images of 370 randomly selected patients who applied to the Department of OralDental and Maxillofacial Radiology of Faculty of Dentistry, Dicle University due to various indications. The total number of roots and root canals, canal symmetry and correlations between the right and left side of the mandible, and the prevalence in men and women were recorded. Data was analzyed using the Chi-Square and Fisher's Exact tests. Canal configurations were evaluated based on the Vertucci classification. Results: The evaluation of CT images of a total of 370 individuals showed that 88.89% of the first premolars and 98.45% of the second premolars were symmetrical. The canal anatomy of the first premolars suggested that 85.98% of the premolars were of Type I, 12.02% were of Type V, and 2% were of Type III based on the Vertucci classification. On the other hand, the canal anatomy of the second premolars revealed that 98.83% were of Type I, 0.67% were of Type V, and 0.5% were of Type III. Conclusions: The prevalent morphology of the multiple canals was Type V, except for the Vertucci classification Type I in the mandibular first premolars. Limited number of canal variations were observed in the mandibular second premolars.

Cyclic and spontaneous movement of a fractured and extruded instrument back into the root canal: A rare case report

Retreatment of endodontically involved teeth may require the removal of obstruction from root canal space. Instrument fracture is an undesirable and stressful incident which can negatively affect the prognosis of the tooth. Any corrective step taken should be performed with utmost care to prevent extrusion of the fragment into periapex. This case report describes a rare occurrence of movement of a fractured instrument during inter-appointment period. A previously treated left mandibular first molar with a fractured instrument was taken up for retreatment. During the course of treatment, the fractured fragment which was previously located in the apical third of the distal canal was dislodged into the periapical region. However, it was found that fragment moved back inside the canal after the inter-appointment period. The same sequence of events repeated before the instrument could be retrieved. Hydrostatic and vascular pressure build due to periapical inflammation could be cited reasons for such a movement.

[Evaluation of the morphology of the nasopalatine canal using cone beam computed tomography]

OBJECTIVE

High precise evaluation of the nasopalatine canal morphology is essential to perform detailed diagnosis and treatment plans in implantology and the orthodontic field. We aimed to study morphometric analysis measurements of the nasopalatine canal.

MATERIAL AND METHODS

In this cross-sectional study, maxillary CBCT images from 125 patients were evaluated in the Maxillofacial Radiology department between 2014-2021. Sagittal views were assessed to determine nasopalatine canal morphology and dimensions. The difference in canal diameter and length between genders was evaluated using an One Way ANOVA test.

RESULTS

There was no significant sex difference among all 125 cases in nasopalatine canal diameter, length, anterior bone plate width. The average length of the nasopalatine canal was 16.49±2.8 mm in male, 16.20±2.9 mm in female, incisive foramen diameter in the sagittal plane was 4.04±0.9 mm in male, 4.02±0.9 mm in female, nasopalatine foramen diameter was 4.63±1.4 mm in male, 4.75±1.2 mm in female. The width of the bone anterior to the canal was 5.89±1.4 mm in males, 5.69±1 mm in females.

CONCLUSION

16-48 aged Mongolian average length of the nasopalatine canal was 16.3 mm, and average incisive foramen width was 4.08 mm, the average width of the bone anterior to the canal was 5.76 mm. Anterior retraction treatment for upper incisor root can be done safely without root resorption around 5.5 mm in the premaxillary alveolar bone.

Prevalence of periapical lesions, root canal treatments and restorations in teeth adjacent to implant- or tooth-supported crowns: A multi-centre cross-sectional study

AIM

To describe the prevalence of periapical lesions, root canal treatments and coronal restorations on teeth adjacent to either implant- or natural tooth-supported crowns using cone-beam computed tomography (CBCT) assessment compared to nonadjacent teeth.

METHODOLOGY

A total of 1249 CBCT volumes were screened by five pre-calibrated observers in 11 health centres. A step-by-step screening protocol was implemented and reviewed every 3 months, and mandatory setting characteristics were established for all CBCT scans using dedicated visualization software. Intra- and inter-rater reliability tests were conducted. The prevalence of periapical lesions, root canal treatments and coronal restorations was recorded on both teeth adjacent and nonadjacent to implant- (predictor 1) or natural tooth-supported crowns (predictor 2). A binary logistic model (Generalizing Estimating Equations test) was used to verify whether the prevalence of periapical lesion, root canal filling and the tooth restorative status are altered when the assessed tooth is adjacent or not to an implant-supported crown (predictor 1); or to a natural tooth-supported crown (predictor 2). Odds ratio and confidence intervals for the dependent variables at both predictors were obtained. The significance level was set at .05.

RESULTS

A global sample of 22 899 teeth was included. Compared to nonadjacent teeth, the prevalence of periapical lesion, root canals treatments and restorative procedures when adjacent to implant-supported crowns was 10.7%, 19.6% and 22.9% higher, respectively, and when adjacent to tooth-supported crowns was 19.3%, 35.6% and 37.4% higher respectively. These results were significant only for variables root canal filling and coronal restoration (p < .0001). Odds ratio to present root canal treatment is 2.57 times higher (CI 1.95-3.39, p = .0001) when the tooth is adjacent to implant-supported crown and 4.39 times (CI 3.49-5.53, p = .0001) when adjacent to tooth-supported crown, whilst for restorative procedure, the odds are, respectively, 1.63 (CI 1.29-2.06, p = .0001) and 2.30 (CI 1.92-2.76, p = .0001).

CONCLUSIONS

Teeth adjacent to both implant- and natural tooth-supported crowns were associated with a higher frequency of root canal filling and coronal restorations.

A prospective cohort study evaluating the outcome of root canal retreatment in symptomatic mandibular first molars with periapical lesions

AIM

To evaluate the impact of various predictors on the outcome of root canal retreatment in symptomatic mandibular first molars with periapical lesions after a minimum of 2 years.

METHODOLOGY

One hundred and twenty previously root canal treated symptomatic mandibular first molars with periapical lesions which were diagnosed as symptomatic apical periodontitis or acute apical abscess with localized intraoral swelling were included. Root canal retreatment was performed by an experienced endodontist using a standardized treatment protocol. The teeth were followed up clinically and radiographically and the radiographic outcome was assessed using a modified periapical index scale (PAI). The cumulative success proportion and the influence of predictors on the outcome of the root canal retreatment were analysed using Kaplan-Meier analyses and log-rank tests, and the hazard ratios for the predictors were also investigated using Univariate Cox Proportional Hazard regression analysis at a significance level of 5%.

RESULTS

Of the 120 teeth, 103 teeth were re-examined with an 85% recall rate. The cumulative success rate was 88% in which 64% were healed and 24% were healing, and failure rate was recorded as 12%. None of the preoperative predictors, including age, gender, soft tissue tenderness, intraoral swelling, size of the lesion, PAI score, apical level and density of root canal filling before root canal retreatment, nor intraoperative predictors, such as active exudate drainage, density of root canal filling after root canal retreatment and restoration type had an influence on the outcome of root canal retreatment (p > .05). The only factor that significantly reduced the success rate of root canal retreatment was the apical level of the root canal filling; when it was more than 2 mm short of the radiographic apex in teeth where apical patency was not established, the success was significantly lower (p = .023).

CONCLUSIONS

Root canal retreatment in symptomatic mandibular first molars with periapical lesions resulted in a success rate of 88%. None of the predictors had a significant influence on the outcome, except for the apical level of the root canal filling after root canal retreatment with short root fillings being associated with significantly more post-treatment endodontic disease.

Five decades of the International Endodontic Journal: Bibliometric overview 1967-2020

AIM

The International Endodontic Journal (IEJ) has served as a platform for research and clinical practice in Endodontics since 1967. This study provides a bibliographic analysis and overview of the publications that have appeared in the IEJ from 1967 to 2020.

METHODOLOGY

A literature search was performed in Elsevier's Scopus database to locate all the publications of the International Endodontic Journal. Various bibliometric software packages including the open-source visualization software Gephi and Biblioshiny (version 2.0) were employed for data visualization and analysis.

RESULTS

A total of 3739 records with citation and bibliographic details were selected and retrieved to allow a bibliometric analysis to be performed. The bibliometric analysis indicates that the IEJ has grown both in terms of productivity and influence. Over time, the journal has been associated with an increase in the number of manuscripts published and the citations they have attracted, but with minor downward fluctuations in citations in the last few years. Bibliographic coupling of the IEJ articles revealed that the major research themes published in the journal include 'endodontics', 'root canal treatment', 'calcium hydroxide', 'apical periodontitis', 'mineral trioxide aggregate', 'microbiology', 'cyclic fatigue', 'cone-beam computed tomography' and 'micro-computed tomography'. Authors affiliated to institutions in the UK were the major contributors to the journal and were linked with other countries such as Brazil, USA and Malaysia. The largest number of publications were from the University of São Paulo, Brazil.

CONCLUSION

The IEJ is one of the leading journals in Endodontology and has been providing a platform for innovative research and clinical reports for more than 50 years. Publications have been associated with a wide range of authors, institutions and countries around the world.

Root canal morphology and symmetry of mandibular second premolars using cone-beam computed tomography

OBJECTIVES

The current study aims to investigate the morphology and symmetry of root canals of mandibular second premolar teeth via Cone-Beam Computed Tomography (CBCT) among a sample of the Saudi population.

METHODS

A total of 1200 CBCT images were examined in the study. The number of roots in the mandibular second premolars was identified, and canal configurations were classified according to Vertucci classification. Bilateral symmetry and association between gender and number of roots and root canal configuration were investigated using a chi-square test was utilized for data analysis and p value was set at 0.05 for significance.

RESULTS

Of the total 2400 Mandibular second premolars, 98.33% were single rooted and 1.67% were double rooted. The prevalence of double roots in females on the right side was significantly higher than that on the left side (p = 0.017), but the opposite was found among males. Only Type I and II canal configurations showed significant differences regarding gender and sides. 98.0% of teeth showed the symmetrical number of roots in both genders. The symmetry in canal configuration was 96.7% in males and 97.3% in females and 99.1% was Type I in both sides, 0.5% Type III, and 0.3% Type IV in both sides.

CONCLUSIONS

The root morphology of mandibular second premolars in the Saudi population demonstrated a high degree of variability. The vast majority of mandibular premolars have a single root with one canal and a low prevalence of two rooted teeth. Contralateral mandibular second premolars exhibited great symmetry of roots and root canal configuration.

Influence of CBCT metal artifact reduction on vertical radicular fracture detection

Purpose

This study evaluated the influence of a metal artifact reduction (MAR) tool in a cone-beam computed tomography (CBCT) device on the diagnosis of vertical root fractures (VRFs) in teeth with different root filling materials.

Materials and Methods

Forty-five extracted human premolars were classified into three subgroups; 1) no filling; 2) gutta-percha; and 3) metallic post. CBCT images were acquired using an Orthopantomograph 300 unit with and without a MAR tool. Subsequently, the same teeth were fractured, and new CBCT scans were obtained with and without MAR. Two oral radiologists evaluated the images regarding the presence or absence of VRF. Receiver operating characteristic (ROC) curves and diagnostic tests were performed.

Results

The overall area under the curve values were 0.695 for CBCT with MAR and 0.789 for CBCT without MAR. The MAR tool negatively influenced the overall diagnosis of VRFs in all tested subgroups, with lower accuracy (0.45–0.72), sensitivity (0.6–0.67), and specificity (0.23–0.8) than were found for the images without MAR. In the latter group, the accuracy, sensitivity, and specificity values were 0.68–0.77, 0.67–083, and 0.53–087, respectively. However, no significant difference was found between images with and without MAR for the no filling and gutta-percha subgroups (P>0.05). In the metallic post subgroup, CBCT showed a significant difference according to MAR use (P<0.05).

Conclusion

The OP 300 MAR tool negatively influenced the detection of VRFs in teeth with no root canal filling, gutta-percha, or metallic posts. Teeth with metallic posts suffered the most from the negative impact of MAR.

A Questionnaire of Digital Radiography and CBCT Use and Knowledge among Lithuanian Dentists

Objectives

Digital radiography is an increasingly used technology in Lithuania. However, there is no published information about using cone-beam computed tomography. The aims of this cross-sectional study performed in Lithuania were (1) to obtain information about the prevalence and accessibility of digital radiography and cone-beam computed tomography usage, and (2) to estimate dental practitioners’ knowledge about this diagnostic method and their need for education.

Material and Methods

Questionnaires consisting of 31 questions were distributed during the 2019 International Dentist Congress in Lithuania.

Results

This study analyses the data obtained from 248 respondents. Most of the clinicians use digital radiographic methods in their practice. The institutions usually have a digital dental X-ray machine, less often a digital panoramic X-ray machine, and least often a cone-beam computed tomography (CBCT) unit. Most dental practitioners performed 1 to 10 CBCT scans per month for adult patients and the most frequent reason for its use was implantation planning. Of the practitioners, 81.7% would like to improve their CBCT knowledge and skills.

Conclusions

The number of digital X-ray machines has increased throughout the last decade. Lithuanian dental practitioners do not excessively use cone-beam computed tomography. Some concerns were raised regarding respondents’ knowledge about exposure factors and this diagnostic method’s performance for paediatric patients. Additional training should be provided to Lithuanian dental specialists.

Management of a Rare Case of Geminated and Fused Central Incisors in the Same Maxillary Dental Arch

A 27-year-old man presented with developmental disorders in the maxillary incisors and asymmetric smile. Differential diagnosis between geminated and fused maxillary central incisors was conducted using cone-beam computed tomography (CBCT). The complexities of root canal system was handled using suitable shaping instruments and ultrasonic activation tips. Root apexes were sealed with mineral trioxide aggregate plugs. The anterior maxillary gingiva was surgically recontoured, and CAD/CAM Zirconia crowns were placed after the gingival healing phase. The combination of the 3D radiological examination, the clinical screening, and the use of a diagnostic wax-up presented a successful approach to manage this rare clinical case.

Evaluation of 10 Cone-beam Computed Tomographic Devices for Endodontic Assessment of Fine Anatomic Structures

INTRODUCTION

The purpose of this study was to classify 10 cone-beam computed tomographic (CBCT) devices using a ranking model according to the detection of fine endodontic structures.

METHODS

A dedicated dentate anthropomorphic phantom was scanned 2 times using 10 CBCT devices without any metal (metal-free condition) and with an endodontically treated tooth containing a metallic post (metal condition). A reference image acquired on an industrial micro-CT scanner was used to register all CBCT images, yielding corresponding anatomic slices. Afterward, 3 experienced observers assessed all acquired CBCT images for their ability to assess a narrow canal, isthmus, and apical delta ramification using a categoric rank from 1 (best) to 10 (worst). Fleiss kappa statistics were used to calculate intra- and interobserver agreements for each CBCT device separately. Based on the observers' scores, general linear mixed models were applied to compare image quality among different CBCT devices for performing endodontic diagnostic tasks (α = .05).

RESULTS

The 10 CBCT devices performed differently for the evaluated endodontic tasks (P < .05), with 3 devices performing better for endodontic feature detection. Yet, in the presence of metal, only 2 devices were able to keep a high level of endodontic feature detection.

CONCLUSIONS

The evaluated endodontic tasks were CBCT device dependent, and their detection was influenced by the presence of metal.

Cone-beam computed tomography cinematic rendering: clinical, teaching and research applications

Cone-beam computed tomography (CBCT) is an essential imaging method that increases the accuracy of diagnoses, planning and follow-up of endodontic complex cases. Image postprocessing and subsequent visualization relies on software for three-dimensional navigation, and application of indexation tools to provide clinically useful information according to a set of volumetric data. Image postprocessing has a crucial impact on diagnostic quality and various techniques have been employed on computed tomography (CT) and magnetic resonance imaging (MRI) data sets. These include: multiplanar reformations (MPR), maximum intensity projection (MIP) and volume rendering (VR). A recent advance in 3D data visualization is the new cinematic rendering reconstruction method, a technique that generates photorealistic 3D images from conventional CT and MRI data. This review discusses the importance of CBCT cinematic rendering for clinical decision-making, teaching, and research in Endodontics, and a presents series of cases that illustrate the diagnostic value of 3D cinematic rendering in clinical care.

In vivo detection of vertical root fractures in endodontically treated teeth: Accuracy of cone-beam computed tomography and assessment of potential predictor variables

Background

This study aimed: (a) to determine the diagnostic performance of cone-beam computed tomography (CBCT) for detection of vertical root fractures (VRFs); (b) to evaluate the predictive value of diagnostic criteria regarding the definition of VRFs; and (c) to examine the robustness of the association of patient-, tooth-, and treatment-related variables with VRFs.

Material and Methods

130 root-filled teeth with signs/symptoms of VRFs underwent clinical and CBCT assessments. Definite diagnosis of VRF was confirmed by endodontic microsurgical (EMS) exploration. Determination of diagnostic performance of CBCT was based on standard algorithms derived from two-way contingency table analysis. Predictive value of diagnostic criteria and the association between predictor variables with VRFs were analyzed using logistic regression models.

Results

VRFs were detected during EMS in 50% of the teeth. Based on the finding of fracture lines on CBCT scans, sensitivity, specificity, and accuracy were 86.2%, 13.8%, and 50%, respectively. Teeth having more than three diagnostic criteria present had significant higher odds for VRF diagnosis. After logistic regression analysis, parafunctional habits, one-canal roots, excessive root canal enlargement, and absence of intra-radicular posts remained as robust predictor variables of VRFs.

Conclusions

Although the sensitivity of CBCT for VRFs detection is high, the risk of false-positive results related to its low specificity makes that all suspected cases must be confirmed by surgical exploration. VRFs cannot be reliably diagnosed by isolated clinical signs/symptoms; instead those teeth possessing more than three diagnostic criteria might be considered practically pathognomonic. The parafunctional habits, one-canal roots, excessive root canal enlargement, and the absence of intra-radicular posts may act strongly/independently for the occurrence of VRFs in endodontically treated teeth.

Key words:Cone-beam computed tomography, diagnostic accuracy, diagnostic surgery, predictor variables, root canal treatment, vertical root fracture.

Invasive cervical resorption of central incisor during orthodontic treatment

Introduction:

Invasive cervical resorption (ICR) is a relatively rare type of ERR (External Root Resorption), in which a localized resorption begins in the cervical area of the tooth, below the epithelial junction and above the ridge crest.

Objective:

Describe the clinical case of an 11-year-old boy with no dental trauma history, presenting moderate crowding and ectopic eruption of the maxillary right central incisor. He had been undergoing orthodontic treatment elsewhere, and his family was dissatisfied with the results.

Description:

A new treatment was indicated, which included rapid maxillary expansion followed by extraction of four premolars. During routine panoramic evaluation, a radiolucid image was detected and a periapical radiograph was requested. At this point, an ICR of the maxillary right central incisor was found. The treatment was cautiously finalized and despite the use of light forces, central incisor was severally compromised by ICR and was therefore extracted.

Conclusion:

This clinical example discusses the importance of routine radiographs for the early diagnoses of ICR.

C-Shaped canal system in mandibular premolars evaluated by cone-beam computed tomography in a population of the Autonomous City of Buenos Aires, Argentina

OBJECTIVE

To evaluate cone-beam computed tomography images in an Argentine population in order to determine the presence of mandibular premolars with C-shaped canal system and classify them.

METHODS

697 images were observed, 170 of them fulfilling the selection criteria. Once established the presence of a C-shaped canal system, premolars were classified using Fan's criteria. Data description was made by frequencies and percentages rates, with a 95% confidence interval according to the score method. Comparisons were assessed by means of the Chi-square test with a significance level equal to 5%.

RESULTS

Of 269 first premolars, 27 teeth showed C-shaped canal system, i.e. 10%, and of 231 second premolars, 4 presented C-shaped canal system, i.e. 2%. Out of 17 patients presenting first premolars in both sides, 6 showed a bilateral C-shaped canal system pattern and 11 did not present this condition. When the condition was unilateral (n = 15), 7 patients showed C-shaped canal in the tooth 3.4 and 8 patients showed C-shaped canal in the tooth 4.4. The second premolars showed C-shaped canals unilaterally. Along the canal, configuration variations at the three-thirds have been observed for the first and second mandibular premolars.

CONCLUSION

The C-shaped canal system pattern prevalence in mandibular first and second premolars was estimated for the first time in an Argentine population, in vivo. The present report contributes to the epidemiological understanding of the anatomical variable of the inner dental configuration and its extrapolation to the clinical practice.

Importance of preoperative diagnostic imaging in treatment of maxillary central incisors with Vertucci's type V root canal configuration – A report of 2 cases

Root canal system typically has a diverse canal configuration. One of the most difficult aspects of ensuring successful endodontic treatment is accurately identifying all canals found in a tooth. Diverse root canal configurations are not uncommon, even if the majority of maxillary incisors have a single root canal. One canal bifurcating into two at the apical third is exceptionally rare, with only two case reports previously reported. For the precise diagnosis of certain anatomical peculiarities, a thorough evaluation of preoperative diagnostic radiographs is highly required. As of periapical radiography, which is the most important diagnostic imaging for determining root canal anatomy, is limited by its two-dimensional nature, technological innovations such as cone beam computed tomography can be extremely beneficial. This paper emphasizes the significance of preoperative diagnostic imaging in the treatment planning of maxillary central incisors with unusual root canal morphology.

To assess the occurrence of middle mesial canal using cone-beam computed tomography and dental operating microscope: An in vitro study

Introduction

Failures of root canal treatments are mainly attributed to missed canals and ignorance about the complex anatomy of the root canal system. One such example of anatomic variation is the middle mesial canal (MMC) in mandibular molars which is often missed, and literature on methods for identifying them is limited.

Aim

This in vitro study aimed to assess the occurrence of MMCs with cone-beam computed tomography (CBCT) and then under magnification in the mandibular first and second molars.

Materials and Methodology

A total of 120 extracted intact human permanent mandibular first and second molars were selected. These were subjected to CBCT imaging and magnification for the detection of MMCs. The percentage of incidence in the detection of MMC was compared between these two methods.

Results

The incidence of MMC detected in mandibular molars using CBCT was 13.33% (16 of 120 teeth), while using a dental operating microscope, the incidence was 18.33% (22 of 120 teeth) and the comparison between the two methods was statistically not significant. The MMCs were classified based on the Pomeranz Classification. The most prevalent canal configuration was a confluent type which was found to be in 72% cases (16 of 22), followed by fin type which was 22.7% (5 of 22) and independent type was only 4.54% (1 of 22). The incidence of the location of MMC orifice was studied. In 50% of the cases, orifice was located closer to the mesiolingual canal, whereas in 27% of the cases, it was closer to the mesiobuccal canal and in 4.95% of the cases, it was detected midway.

Conclusions

Since the incidence of MMC was higher with the use of a microscope, it is preferred to use simpler, chairside aids like magnification and ultrasonic troughing. On the other hand, one should be judicious while subjecting a case to preoperative CBCT evaluation owing to its ionizing radiation.