Successful Endodontic Treatment Research Articles

Influence of Cavity Designs on Fracture Resistance: Analysis of the Role of Different Access Techniques to the Endodontic Cavity in the Onset of Fractures: Narrative Review.

In recent years, new endodontic access techniques have been proposed with the aim of preserving as much dental tissue as possible for subsequent prosthetic rehabilitation. It has indeed been demonstrated that the success of this therapy is essential and dependent on the proper execution of endodontic cavity access. The main objective is to provide a comprehensive and up-to-date overview of the new access techniques in endodontics in order to guide clinical practice toward a more precise and qualitative approach. As of today, there is still no universally standardized and recognized taxonomy for the different access cavity designs described in the literature. It has been observed that there are various nomenclatures in the literature. The cavity access designs described mainly in the literature can be categorized into six groups: Traditional Access Cavity (TradAC), Conservative Access Cavity (ConsAC), Ultra-Conservative Access Cavity (UltraAC), Truss Access Cavity (TrussAC), Caries-Guided Access Cavity (CariesAC), and Restoration-Guided Access Cavity (RestoAC). The drafting of this narrative review followed the indications of the SANRA (Scale for the Assessment of Narrative Review Articles). A search for scientific articles was conducted on the PubMed and SCOPUS databases, using the following search query: ((truss) OR (conservative) OR (ninja) OR (traditional)) AND access AND endodontic. The initial search yielded a total of 941 articles. After removing duplicates using EndNote X8 software, the number of articles decreased to 785. By applying the inclusion and exclusion criteria, a total of 64 articles were obtained. Among these, 20 articles were finally selected for the purposes of this review, 11 literature reviews and 9 ex-vivo studies. Studies on fracture resistance have yielded heterogeneous results. For anterior teeth, studies do not find a significant relationship between different endodontic access cavities and fracture resistance. However, in the posterior sector, there is more discrepancy and many positive results for minimally invasive access cavities seem to relate to molars. Therefore, it can be concluded that the evidence supporting the influence of endodontic preparations on dental fracture resistance is still limited. Research on new endodontic access techniques holds significant clinical relevance in contemporary endodontics. The evolution of dental technologies, including cone beam computed tomography (CBCT) and computer-guided cavity preparation, has ushered in the era of minimally invasive endodontics. This shift aims to enhance the precision and quality of endodontic treatments while preserving maximum healthy dental tissue for subsequent prosthetic rehabilitation. The success of endodontic therapy is closely tied to the proper execution of access to the endodontium, influencing all phases of endodontic treatment and playing a role in determining fracture resistance for subsequent rehabilitation phases. The dichotomy between traditional and minimally invasive approaches has spurred clinical investigations. Specifically, within the scientific community, doubts have been raised about the potential limitations of minimally invasive access cavities. Concerns include their impact on canal orifice localization and raise questions about their influence on the overall success of endodontic treatment. This review holds clinical significance as it sheds light on the evolving landscape of endodontic access techniques, analyzing the anatomical trajectory, carefully examines the transition to minimally invasive approaches, and critically assesses existing scientific evidence and concerns surrounding these developments, contributing to an informed decision-making process in clinical practice.

Comparison of Antibacterial Efficacy of Triple Antibiotic-Loaded Hydrogel Versus Modified Triple Antibiotic-Loaded Hydrogel as Intracanal Medicament Against Enterococcus faecalis: An In vitro Study.

Triple antibiotic paste (TAP) is known to have an essential role in the success of endodontic treatment by eliminating pathogens from the root canal system. Unfortunately, it causes discolouration and cytotoxicity at high concentrations. The objective of this research was to assess and compare the antimicrobial effectiveness of various concentrations (1 mg, 5 mg, 10 mg) of TAP, TAP hydrogel (TAPH), M-TAP, and M-TAP hydrogel (MTAPH) against Enterococcus faecalis. The agar well diffusion method was used to assess the antibiotic sensitivity of the following intracanal medicaments: TAP (ciprofloxacin, metronidazole, and minocycline) mixed in a ratio of 1: 1: 1; TAPH, M-TAP (ciprofloxacin, metronidazole, and amoxicillin), M-TAPH and plain hydrogel. Each tested medicament was individually evaluated for its antimicrobial activity against Enterococcus faecalis. Structural and topographical characterisation were analysed using a Scanning Electron Microscope (SEM) and interpreted using ImageJ software. A microdilution broth test was performed to examine the minimum inhibitory concentration and minimum bactericidal concentration (MBC) of M-TAP and TAP. Except for the plain hydrogel, M-TAP and hydrogel and TAP and hydrogel showed significantly varied inhibitory zones at different concentrations. M-TAPH showed the highest mean zone of inhibition of 21.6, 33.33 and 38.0 mm at a concentration of 1, 5, and 10 mg/mL when compared to TAPH, which showed a mean zone of inhibition of 3.3 mm,12.3 mm, 21.3 mm at the respective concentrations. The MIC study shows that more than 75% of Enterococcus faecalis growth was inhibited by M-TAP at a concentration of 5 μg/mL, whereas TAP showed inhibition at a concentration of 35 μg/mL. MBC results indicate that almost 99.9% of the bacterial population was killed at a concentration of 100 μg/mL (10-1) for TAP and 10 μg/mL (10-2) for M-TAP. The antibacterial efficacy of M-TAP was significantly higher than TAP. Application of M-TAP at lower doses is advised to overcome the disadvantages seen with TAP.

Influence of Passive Ultrasonic Irrigation of the Photosensitizer Used in Photodynamic Therapy on Microbial Reduction in the Root Canal System: An in Vitro Study.

The success of endodontic treatment is based on microbial reduction promoted by the interaction of chemical and mechanical procedures. Photodynamic therapy (PDT) is used as an adjunct to conventional treatment, with significant microbial reduction. This study aimed to evaluate the influence of passive ultrasonic irrigation (PUI) of the photosensitizer (PS) used in PDT on microbial reduction in the root canal system. Forty-five mesiobuccal root canals from extracted human mandibular molars that were inoculated with standard strains of Enterococcus faecalis, Candida albicans, and Streptococcus mutans for 21 days were selected. The root canals were prepared using the ProTaper Next system and randomly divided into 3 groups (n=15): 1) PDT: PDT alone; 2) PUI+PDT: PUI followed by PDT; and 3) PUI/PS+PDT: PUI of the PS followed by PDT. Microbiological samples were collected from the canals before and after using the protocols described above. The data were analyzed by analysis of variance (Tukey's test) at a significance level of 5%. Microbial counts before PDT, PUI+PDT, and PUI/PS+PDT did not differ significantly (P>0.05), showing methodological standardization in the microbial contamination of the root canal system. There was a significant reduction in microbial counts after PDT (61.05%), PUI+PDT (65.04%), and PUI/PS+PDT (68.58%) (P<0.01), but with no statistically significant difference between the three groups (P>0.05). Based on the present findings, it was concluded that the combination of PUI with PDT or PS activation did not influence microbial reduction achieved by PDT alone.

Endodontic management of maxillary first molar with two palatal canals - A case report

An awareness and understanding of unusual root canal morphology is essential as it deter-mines the successful outcome of endodontic treatment. Aberrations in root canal anatomy are commonly occurring phenomena. I report a clinical case of a maxillary left first molar with two palatal root canals. The morphology is atypical because it has two palatal canals with separated orifices, running parallelly but joined at the apex. Modifications to the usual access opening and examination of the pulpal floor for additional canals are essential in such atypical cases for the success of endodontic treatment

A rare case of maxillary third molar with four roots and five root canals and its endodontic management with the help of cone-beam computed tomography

Maxillary third molars (M3) have unpredictable pulp morphology. They usually have one to three roots; any additional is called an accessory root. Various in vitro and in vivo studies examined its root canal morphology but none of the case reports has been published regarding the successful endodontic treatment of M3 with four roots and five canals. Herein, a case of a 42-year-old male with a complaint of severe pain in M3 is presented. Endodontic treatment was carried out and four canals were negotiated and cleaned. To decipher, the pulp canal complex anatomy cone-beam computed tomography was advised and the presence of the fifth canal (MB2) was confirmed, negotiated, cleaned, and obturated. This report is by far the first case of endodontic treatment of M3 to be reported in the Indian population with four roots and five canals.

Evaluation of Root Canal Morphology of Mandibular Premolars Using Cone-beam Computed Tomography in Golestan Province, North of Iran.

Successful endodontic treatment depends on completely clearing, shaping, and filling the prepared canals. Knowledge of the common and aberrant varying pulp anatomies is essential for suitable root canal treatment. Since, this anatomy is complex and varies morphologically in different populations. This study aims to determine the number of roots, canals, and evaluation of mandibular premolars canals using cone-beam computed tomography (CBCT) images in one of Iran's northern provinces (Golestan). CBCT axial, coronal, and sagittal slices of two hundred and twelve mandibular premolars were analyzed to determine the number of roots and canals based on Vertucci type. The images were analyzed in a one-millimeter slice in mesiodistal and buccolingual dimensions based on gender. The data were analyzed using the Chi-score test to compare the components if the defaults were not established. A significance level of 0.05 was considered. Of the two hundred twelve teeth evaluated, 130 (61.3%) were first premolars, and 82 (38.6%) were second premolars. Most first premolars (78.5%) and almost all second premolars (97.6%) had one root. Morphological types of root canals were identified based on Vertucci's classification types I, II, III, IV, V, or VIII, and type I was the most frequent. There were no significant associations between number of roots and sex (P>0.05). Mandibular premolars mostly had one root and type I Vertucci morphology. The frequency of two-canal premolars was higher in the male population. Although the abundance of two or three roots with different morphologies was also observed, the possibility of the presence of an additional root canal should be considered.

Evaluation of apically extruded debris using protaper universal, protaper next, one curve, Xp shaper, and edge file: An in vitro study

Introduction: Effective chemo-mechanical debridement is essential for a successful endodontic treatment. The present study aimed to determine the quantity of apical extruded debris during instrumentation by Protaper Universal (PTU), Protaper Next (PTN), One Curve, Xp Shaper, and Edge file systems. Materials and Methods: Fifty human maxillary first molars were chosen for this study. The palatal roots of teeth were decoronated using a diamond disk at length 13 mm, Then 50 samples were randomly divided to five groups (n = 10) (Group I: PTU file; Group II: PTN file; Group III: One Curve file; Group IV: XP Shaper file; and Group V: Edge file). After instrumentation, the root-cap assembly was detached from the glass vial. After that, the outer surface of the root was rinsed in the vial by 2 mL of normal saline to eliminate any debris that could have attached to it. The samples’ vials were stored in a hot air oven for 2 h at 100°C to allow moisture to evaporate before the debris was weighed with an electronic balance that had a 0.0001 g precision. Results: The data were statistically analyzed, and the greatest amount of extruded debris was in the PTU file (mean = 1.596), which had a statistically significant difference (P &lt; 0.05) with all other groups. Conclusion: Even after taking the study’s limitations into account, apical debris extrusion was observed in all groups. In contrast to the PTU file system, which exhibited the greatest value, the One Curve file system showed the lowest mean value of apical extrusion debris.

Incidence of C-shaped canals in mandibular second molars in patients visiting Rehman College of Dentistry, Khyber Pakhtunkhwa (KPK), Pakistan

Objective: The objective of the study was to evaluate incidence of C-shaped canals in mandibular second molars using Cone Beam Computed Tomography. Study Design: Cross Sectional, Descriptive study. Place and Duration: This study was undertaken in Department of Radiology, Rehman College of Dentistry, Peshawar, from 15th June 2022 till 15th December 2022. Methodology: Cone Beam Computed Tomography scans of 60 patients of both genders between 18 and 60 years of age were studied for the presence of C-shaped canals in mandibular 2nd molars. Results were analyzed with the help of SPSS version 21. Chi-square was applied for comparison of male and female groups. Results: Cone Beam Computed Tomography scans of 60 patients of both genders between 18 and 60 years of age were studied for the presence of C-shaped canals in mandibular 2nd molars. Results were analyzed with the help of SPSS (version 21). Chi-square was applied for comparison of male and female groups (p &gt; 0.05). Conclusion: Incidence of C-shaped canal is high in patients with mandibular 2nd molars. Endodontists need to be vigilant for the existence of C-shaped canals and proper imaging of these canals is essential for successful endodontic treatment. Keywords: Root Canal Therapy, Molar, C-Shaped Canals, Pulp, Cone Beam Computed Tomography, Endodontic. How to Cite This: Rehman AZ, Alam S, Khan IA, Arbab KN, Khalid MD, Askar H. Incidence of C-shaped canals in mandibular second molars in patients Visiting Rehman College of Dentistry, Khyber Pakhtunkhwa (KPK), Pakistan. Isra Med J. 2023; 15(2): 70-73. DOI: https://doi.org/10.55282/imj.oa1373

Comparison of EDTA and Boric Acid Irrigation in Terms of Root Canal Dentin Microhardness and Sealer Penetration Depth

Chemo mechanical preparation is one of the important stages for successful endodontic treatment, and Boric acid has been proposed as an alternative irrigation solution for root canal treatment. Objective: The purpose of this study was to evaluate the effect of irrigation with boric acid (BA) and EDTA on the mineral content and microhardness of dentin and penetration of the AH Plus root canal sealer. Methods: 63 single-rooted teeth were instrumented. Microhardness analysis, 45 teeth were cut longitudinally and then transversely to obtain dentin. Pre- and post-treatment microhardness values were measured. The samples were randomly assigned into 3 groups (n = 15) for irrigation solution: distilled water, 17% EDTA, and 5% BA. The 18 roots were irrigated with three solutions (n = 6). Nine of the roots were filled with AH-Plus for confocal laser scanning microscopy analysis, and the others were used for XRD analysis. Results: The results were evaluated with the ANOVA test. BA caused a significant decrease in microhardness value in apical and coronal parts (p &lt; 0.05), while EDTA reduced only in coronal parts (p &lt; 0.05). Conclusion: BA provided higher sealer penetration ability. BA reduced the microhardness and provided better sealer penetration.

Unprepared areas and centralization of oval canals prepared with WaveOne Gold or XP-endo Shaper: microcomputed tomographic analyses.

To evaluate the performance of two endodontic systems in oval canals by investigating the changes in volume, unprepared areas, and centering ability of XP-endo Shaper (XPS) and WaveOne Gold (WOG) in oval canals using microcomputed tomography (micro-CT). Thirty mandibular canines were scanned before and after preparation with WOG (25/.07 and 35/.06) or XPS (30/.01) to evaluate the volume, surface area, and canal centralization at 4 mm and 10 mm from the apical foramen. Volume and surface area increased significantly after preparation with both systems (p<0.05). However, no significant difference was observed in the unprepared areas, regarding either the entire canal (26.21% for WOG and 30.10% for XPS), or the apical segment (18.82% for WOG and 14.63% for XPS) (p >0.05). Both systems maintained canal centralization, with no difference between them. XPS and WOG had similar shaping abilities in the mandibular canine, but left almost one third of the unprepared areas.

Evaluation of the curvature of the mesio-vestibular canals of the mesial roots of lower molars

The correct biomechanical preparation of root canals is fundamental in endodontic therapy and depends on a detailed understanding of the internal anatomy of the teeth. The objective of the study was to evaluate the degree and radius of curvatures of the mesiobuccal canals in the mesial roots of extracted lower first molars from Ecuadorian patients. Seventy lower first molars were analyzed using radiographic techniques and AutoCad 2013 tracing, applying the Schneider and curvature radius methods. The results showed that the majority of the canals presented moderate curvature according to both methods. A statistically significant difference was observed between the angles and radii of curvature. It is concluded that precise knowledge of these curvatures is crucial for the planning and success of endodontic treatment, and it is recommended to consider the application of neutrosophy in future studies to improve measurement accuracy

Narrative literature review on the complexity of the internal anatomy of root canals

The intricate and highly variable nature of the internal anatomy of root canals poses significant challenges for effective endodontic treatments. The aim of the study was to interpret the complexity of the internal anatomy of root canals through a narrative literature review. This study adopted an exploratory methodology and was characterized by its observational and descriptive nature, analyzing information from a cross-sectional and retrospective perspective. An exhaustive evaluation of 25 articles was conducted on PubMed, Google Scholar, and Elsevier through ScienceDirect, from 2016 to 2023. This study revealed that a deep understanding of the internal root anatomy and its variations is essential for the success of endodontic treatments, highlighting the importance of advanced diagnostic techniques, such as Cone Beam Computed Tomography (CBCT), for identifying anomalies. It was found that anatomical variations, including C-shaped canals, lateral canals, and apical deltas, are more prevalent in posterior teeth. Moreover, anterior lower teeth rarely exhibit more than one root, with Vertucci type I classification predominating in their internal anatomy, which implies less complexity compared to posterior teeth. It concludes that success in endodontics critically depends on detailed knowledge of the internal root anatomy. The findings emphasize the need to apply precise diagnostic techniques and adapt treatment strategies to the specific anatomical complexity of each tooth, especially in those with more complex root configurations

Irriguesit endodontikë

Irrigation in endodontics is one of the key factors in the success of endodontic therapy. There are many irrigants that are used in endodontics with wide spectrum of anti- microbial effect, biocompatibile, help lubricate the root ca- nal, remove debris, but we still do not have an ideal irrigant that can fulfill all the necessary conditions for successful endodontic treatment. Therefore, this review will describe the proper characteristics and methods of irrigation in end- odontics.

Iontophoresis use for increasing drug penetration into root canals and dentinal tubules: A proof-of-concept study

IntroductionThe success of endodontic treatment depends on the significant disinfection of the root canal system, its irregularities, and dentinal tubules. However, achieving complete disinfection remains challenging, with frequent failures and occurrence of secondary infections. Here, we propose using iontophoresis to increase the penetration and distribution of disinfecting agents into root canals, using methylene blue for proof-of-concept. MethodsThe marker was applied in bovine root canals, and the radial distribution of the dye in the dentinal tubules was evaluated by optical microscopy. Iontophoresis was applied at 0.5 and 1.5 mA for 5 and 15 min. ResultsA significant statistical difference (p < 0.05) was observed in the marker penetration between passive and iontophoretic applications. Both current density and application time had an important effect on methylene blue distribution, with a greater efficacy delivery to the apical region achieved after 1.5 mA for 5 min or 0.5 mA for 15 min, showing longer application time can compensate for lower application current. ConclusionIontophoresis increases the penetration and distribution of methylene blue into bovine root canals and dentinal tubules, including its innermost portions. Clinical significanceIontophoresis has shown to be a promising technique for root canal and dentinal tubule disinfection.

Modern nickel-titanium rotary systems in endodontic treatment

Background: One of the most important steps in endodontic treatment is the preparation of a uniform space, the use of endodontic irrigant and creating space for the endodontic filling. Therefore, improving endodontic treatment techniques is one of the most important tasks of modern dentistry. The success and effectiveness of endodontic treatment is largely determined by the quality of chemo-mechanical root canal treatment. In recent years there has been a major emphasis on the use of rotary mechanical instrumentation systems, namely the use of nickel-titanium (NiTi) alloys, which due to their properties represent a favorable flexibility in the instrumentation of difficult anatomies. Material and methods: 20 patients were examined and treated. They were divided into 2 groups: for the treatment of 6 patients was applied the Protaper Universal rotary system. In the second group of 14 patients to whom mechanical instrumentation was applied, were 7 patients following the Protaper Next and the other 7 Dc Taper with different pulpal and periodontal diseases. Results: Mechanical instrumentation was performed on different nosological entities, the prevalence being acute pulpitis. Among instrumented teeth, the prevalence was on the side of pluriradicular teeth. Conclusions: The practical application of different NiTi rotary systems has to be determined individually, as each clinical case has its own practical properties. But the success of an endodontic treatment depends not only on the rotary instruments used and, on the method, chosen, but also on the practitioner’s experience, detailed knowledge of the properties and step-by-step instrumentation protocols.

Long-term follow-up of equine incisor endodontic treatments using an orthograde technique.

This retrospective clinical study was performed to determine the suitability and success rate of endodontic treatment of equine incisors presenting with apical and periapical disease. All horses presented to a referral equine dental clinic between March 2013 and December 2019 specifically selected as candidates suitable for endodontic treatment were included in this study. Initial clinical and radiographic presentation of incisor disorder cases suitable for endodontic treatment were recorded (88 incisors) and follow-up examination for long-term viability (8 months to 5 years) was performed in cases involving 32 incisors in total. A total of 68 horses with 88 incisors were included in this study for endodontic restorative treatment. Different dental materials were used, with a temporary 3-layered technique using calcium hydroxide apically and temporary cement and resin composite occlusally most commonly used at the first treatment. Complete obturation with resin composite was performed in 48% of the cases requiring second treatments (50 incisors). Follow-up examination involving 32 incisors showed that successful endodontic treatment was achieved in 75% of the teeth treated. Endodontic treatment of diseased incisors is a viable option in equid patients with a success rate comparable to humans in practice. The use of flowable resin composite as an obturation material has been shown to be successful at either the second treatment or in carefully selected patients at the first treatment.

Acurácia do método eletrónico versus método radiográfico na determinação do comprimento de trabalho: revisão sistemática integrativa

Introduction: The radiographic method is widely used to calculate the working length (CT). However, it presents limitations that, to overcome them, apical electronic locators (LEAs) were developed to allow greater accuracy and reliability in determining the CT. Objective: The present study aims to perform an integrative systematic review and gather the available scientific evidence on the method that allows greater accuracy in determining the CT between the radiographic method and the electronic localisation method (LEA). Materials and Methods: The literature search was performed on the PubMed platform using keywords combined through the Boolean operator AND as follows: ("endodontics" AND "electronic apex locator" AND "radiographic measurement") and ("endodontics" AND "electronic apex locator" AND "radiographic measurement" AND "odontometry"). Results: 68 articles reporting comparative studies performed between the methods, radiographic and LEA, were identified. Eleven studies were included, of which, in some cases, LEAs showed better results than non-digital periapical radiographs. The studies indicate that although there are differences between the two methods, with greater accuracy in determining LEA, the differences did not prove to be statistically significant. In the presence of irrigating solutions, sodium hypochlorite revealed more significant discrepancies in CT determination with the LEA method. Conclusion: The two methods, radiographic and LEA, should be used in association since each has particularities that present more significant benefits enhancing the success of endodontic treatment and a better and more complete treatment for patients.

Maxillary Second Molar: An Unconventional C-shaped Canal Configuration - A Case Report

Understanding the plethora of potential canal configurations is crucial for successful endodontic treatment, as it allows for optimal preparation of the canals by accounting for any deviations from the norm. This case highlights the rare occurrence of a C-shaped canal configuration found in a maxillary second molar, with a reported occurrence rate of only 3.8%. Although C-shaped canals are more commonly reported in mandibular second molars, recent literature has also observed such canal configurations in other teeth, including maxillary first molars, maxillary premolars, and mandibular premolars. The dental profession often faces a formidable task when dealing with the complex nature of C-shaped canal configurations during endodontic therapy; however, by anticipating and proactively managing these intricacies, dentists can avoid causing irreversible harm to the tooth.

The Conclusion of Diabetes Mellitus on Endodontic Treatment Result: A New Appraisal

Background- The writers used a custom-built electronic utmost agreement to examine endodontic analytical and management consequence measurements in patients with and without diabetes. Methods- The medical histories and endodontic management statistics for nonsurgical endodontic patients treated in predoctoral and postgraduate specialty clinics were entered into an electronic record system. A entire of 5,134 cases (including 284 cases in patients with diabetes) were treated, and 150 cases (including 63 cases in patients with diabetes) had follow-up data two years or additional postoperatively. The writers applied and multivariate evaluates to control significant issues touching endodontic analysis and treatment. Results- Patients with diabetes had enlarged periodontal infection of teeth with endodontic connection associated with patients who did not have diabetes. There was a movement near enlarged suggestive peri-radicular illness in patients with diabetes who conventional insulin, as well as flare ups in all patients with diabetes. Two years or longer post-operatively, 58 percent of cases surveyed were effective. Older age, the absence of preoperative lesions, the presence of permanent restorations and longer postoperative evaluation phases all were supplementary with an effective outcome. A multivariate examination displayed that in cases with preoperative peri-radicular lesions, a history of diabetes was supplementary with a meaningfully complete successful outcome. Conclusions- Patients with diabetes have enlarged periodontal disease in teeth involved endodontically and have a reduced likelihood of success of endodontic treatment in cases with preoperative peri-radicular lesions. Clinical Implications- Patients with diabetes who are preserved endodonticaly should be evaluated carefully and be preserved with operative antimicrobial root canal regimens, mainly in cases with preoperative lesions.

A Cone Beam Computed Tomography-Based Investigation of the Frequency and Pattern of Radix Entomolaris in the Saudi Arabian Population.

Background and Objectives: An understanding of the anatomical complexity of teeth is a significant factor for a successful endodontic treatment outcome. The aim of this study was to explore the frequency and pattern of distribution of radix entomolaris (RE) in mandibular first molars (MFMs) of a Saudi Arabian subpopulation using CBCT scans. Materials and Methods: This study was conducted at dental clinics of Qassim University from February to May 2023 by evaluating CBCT scans that were previously obtained for diagnostic purposes. Scans of Saudi national patients with bilaterally present MFMs and fully formed root apices were included. Conversely, scans with one/or two missing MFMs, MFMs with incomplete root apices, full- or partial-coverage prosthesis, endodontic treatment, and associated radicular resorption were excluded from study. A total of 303 CBCT scans with 606 bilateral MFMs were analyzed by two calibrated evaluators for the presence of, and type according to Song's typolgy of RE. The data were analyzed using SPPS-24. The descriptive variables were documented as frequencies and percentages. The chi-square test was used to determine the association between the prevalence of RE with the gender, jaw side and age group. Both inter-rater and intra-rater agreements were estimated for detecting and classifying RE using Cohen's kappa test. Results: The sample had 63.7% males and 36.3% females. The prevalence of RE was 6.6%, with Song's type III (57.5%) as the most common variant. Absolute agreement was noted between the raters about the presence of RE and very strong agreement was noted for the classification of the RE. Conclusions: RE is an uncommon finding among the mandibular first molars of the Saudi population without any gender and quadrant predilection. The clinicians' knowledge of the presence and Song's type of RE may contribute towards the enhancement of endodontic treatment outcomes.