Root Canal Length Research Articles

Maxillary Canine with two roots and two canals: A case report

Introduction: Knowledge of the anatomy and root canal system is of fundamental importance for a successful endodontic treatment. Maxillary canines unusually possess two root canals. Aim: The present study aims to present a maxillary canine with two roots and two canals through a clinical case. Case report: A male patient was referred for the treatment of a root perforation of the tooth 23. Clinical examination revealed the presence of vestibular fistula and mild pain with vertical and horizontal percussion. Through a tomographic examination, the presence of two roots and two root canals was observed in addition to a radiolucent lesion at the middle third of the roots but without perforation in the middle third. Coronary opening and the localization of the vestibular and palatal canals were performed. The root canal length was performed with Romi Apex A-15® foraminal locator and instrumentation was conducted by using Protaper Next® system. Due to the presence of fistula, calcium hydroxide manipulated with propylene glycol was used as intracanal medication for 30 days. After this period, the root canals were filled with gutta-percha and AH Plus® cement and a new tomographic examination was undertaken, which confirmed the complete filling of the root canals and the absence of root perforation. Conclusion: Given the above, endodontic professionals shall be aware of possible anatomical variations and make use of auxiliary resources when appropriate, such as cone beam computed tomography (CBCT), to ensure correct diagnosis and, consequently, a successful root canal treatment.

Root canal length measurement of molar teeth using conebeam computed tomography (CBCT): comparison of two dimensional versus three-dimensional methods.

This study aimed to evaluate the validity of 2-dimensional (2D) and 3-dimensional (3D) cone-beam computed tomographic (CBCT) root canal length measurements of molar teeth compared with actual root canal lengths and the influence of canal curvature on the accuracy of CBCT measurements. Seventy root canals of 24 molar teeth were scanned using CBCT, and the root canals were categorized as; 'straight/curved,' 'highly curved,' and 'multiple curved.' The 2D measurements were performed within a suitable slice between the major foramen and the corresponding cusp. The 3D measurements were performed within the slices in regular intervals of axial planes in between the same reference points. The reproducibility and reliability of the methods were analyzed by intraclass correlation coefficient. Differences between the actual and CBCT root canal lengths were evaluated by chi-square and McNemar tests if the measurements were within acceptable limits of ±0.5 mm. Both methods were found to be reproducible and presented excellent reliability. However, the 3D method was significantly more accurate, with an 85.7% frequency of measurements within acceptable limits (p<0.05). In 'multiple curved' root canals, the 3D method presented more reliable measurements than the 2D method. For 'straight/curved' root canals, the 2D method gave results significantly closer to the actual root canal length in comparison with 'highly curved' root canals (p<0.05). The 3D measurements are more accurate than 2D measurements. If an already existing CBCT is present, it could be an alternative method for predetermination of root canal lengths in molar teeth.

Accuracy of Working Length Measured by Apex Locator and Digital Radiography

OBJECTIVE: The objective of this study was to compare the measurements of electronic and radiographic method of working lengths calculation with actual working length of root canals. Precise working length determination is the most important part for successful root canal procedure. The most commonly used methods to determine the working length in root canal treatment are radiography and electronic apex locator. METHODOLOGY: A cross sectional study was done over a period of 06 months in the Department of Operative Dentistry, Fatima Memorial Hospital, Lahore. Sixty patients who were recommended extraction of their premolar teeth with sixty canals were selected by convenience sampling. The Root ZX* apex locator was used to determine electronic working length exactly identifying the apical constriction. Reference points were identified and radiographic working length were determined 1mm short of radiographic apex. The teeth were extracted along with file cemented before extraction inside root canal. The actual length of the root canal was then calculated using the same files and reference point with 3.5X magnification. Pearson chi square test was applied to compare the apex locator and digital radiographic measurement with actual working length. RESULTS: The Root ZX® apex locator was 95% accurate to identify the apical constriction as compared 70% accuracy given by radiographs within 0.5 mm of the apex. CONCLUSION: Electronic apex locator was more accurate as compared to digital radiography in working length determination. KEYWORDS: Working length (WL), Electronic apex locators (EAL), Radiographic working length(RWL), Apical constriction (AC) HOW TO CITE: Khan GI, Khan MT, Ehsan S, Fayyaz A, Malik HA, Hussain S. Accuracy of working length measured by apex locator and digital radiography. J Pak Dent Assoc 2021;30(1):24-28.

Evaluation of apical transportation and apical root sealing in root canals prepared with mtwo rotary system with and without apical enlargement – an in vitro study

The aim of this study was to evaluate apical transportation and apical root canal sealing after root canal filling in human teeth prepared with MTwo® Rotary System with and without apical foramen enlargement. Twenty mandibular premolars were divided into two groups (n=10). Group 1 had root canals prepared 1mm beyond the apical foramen. Group 2 had root canals prepared 1mm below the root canal length. After chemo-mechanical preparation, samples were submitted to scanning electronic microscopy. Apical foramen images had 75x magnification at standardized positions, allowing measurements from the apical foramen area before and after root canal preparation, and after root canal filling. Apical foramen shape and apical transportation, as well as its level of circumferential filling after root canal preparation were accessed using the Image Subtraction System. Scanning electronic microscopy analysis demonstrated that samples of Group 1 showed larger foraminal diameter than samples of Group 2 (p&lt;0.05). Apical foramen transportation was statistically different between Groups 1 and 2 (p=0.0108). Furthermore, the apical foramen sealing also differed statistically between groups 1 and 2 (p=0.0007) and 100% of samples of Group 1 showed apical root canal sealing. Apical root canal sealing was more effective when the root canal was prepared with apical foramen enlargement, even when the apical transportation was detected.

A Comparative Study to Evaluate the Effect of Ultrasonic Agitation on Push - Out Bond Strength of Three Root-End Filling Materials: An In Vitro Study

Aim: To evaluate the effect of ultrasonic agitation for retrograde biodceramic root repair, MTA and biodentinefilling materials on push-out bond strength to dentine walls.Materials and Methods: Ninety extracted human teeth with single straight roots were selected randomly.After disinfection and cleaning, the coronal portions were sectioned to standardize the root canal length at15mm. following root canal shaping, obturation and apical roots resection, retrograde cavities were prepared.Teeth were categorized depending on the filling material used into three groups, 30 teeth each. Group Afilled with bioceramic root repair material, B with MTA and C with Biodentine material. These groups weredivided in to three subgroup (n=10). Subgroups:A1, B1, and C1 cavities were filled with the aid of condenser.A2, B2, and C2 with ultrasonic agitation of material for 30 seconds. A3, B3, and C3 with ultrasonic agitationof material for 60 seconds. Push-out bond strength test was done for the samples to specify bond strengths atthe cement/dentin interfaces. The specimens were examined using a stereomicroscope to estimate the modeof failure. Data were statistically analyzed using two-way ANOVA and Bonferonni test.Results: Ultrasonic agitations increase the bond strength for all cements. BiodentineTM, PD™ MTAWhiteand TotalFill®BC RRM™ were significantly increased (P<0.05). While, increasing the time of ultrasonicwas statically non-significant among groups.Conclusions: Ultrasonic agitation of root-ending filling materials showed increase in push-out boundstrength to dentine walls.

Penetration depth of sodium hypochlorite into dentinal tubules influenced by different agitation systems

Objectives: To compare the effect of different agitation systems on the penetration depth of sodium hypochlorite into dentinal tubules: An in vitro study.Background: Studies have found the presence of bacteria in dentinal tubule up to 200 μ. Passive irrigation using NaOCl may not adequately eliminate these bacteria. Hence, it is mandatory to use agitation systems during irrigation and disinfection of root canal.Materials and Method: Eighty extracted teeth with single canals were used. Standardized access cavity preparation and working length determination were done using visual method. All canals were instrumented till #30, 6%. All samples were immersed in crystal violet dye. The samples were randomly divided into four groups depending on the type of agitation system used (n = 20): Group A: manual dynamic agitation (MDA), Group B: EndoActivator (EA), Group C: EndoUltra (EU), and Group D: EndoVac (EV). Each agitation system was used with 5 ml of 5.25% NaOCl, and each tooth was sectioned into two halves. These sections were analyzed under a stereomicroscope, and NaOCl penetration depth was measured at coronal, middle, and apical third levels.Statistical Analysis Used: Statistical analysis was performed using one-way ANOVA and Tukey's post hoc test.Results: At all levels of examination, EU significantly showed a maximum penetration depth of NaOCl throughout the length of root canal, followed by EA, MDA, and EV.Conclusion: Ultrasonic agitation using EU is the most effective method to disinfect the dentinal tubules throughout the length of root canal than EA and MDA. EV showed the least penetration depth of sodium hypochlorite.

Simulated Evaluation of Tooth Fracture Resistance during Instrumentation with Single-and Multi-file Rotary Systems.

Use of rotary files in root canal preparation is inevitable due to their high speed and reduced duration of treatment. However, microcracks and even root fracture may sometimes occur in teeth where canal(s) is/are prepared using these devices. The purpose of the current study was to compare NeoNiti single-file with RaCe multi-file rotary systems. An accurate scanner designed detailed three-dimensional file models, and a simulated model was developed using canal-specific features; including dentin thickness, root canal length, taper rate and root canal curvature. Cleaning and shaping conditions were simulated with appropriate speed and crack conditions for both types of files on the computer. Strain accumulation sites in the root dentin wall where microcracks was likely to occur were simulated and investigated. Abaqus and ANSYS software were used to perform finite element simulations. RaCe files with 0.04 taper caused the lowest level of stress (34.33 MPa) to the simulated canal. Conversely, the highest level of stress (62.35 MPa) was applied by 8% NeoNiti file to the simulated canal. Based on the present experimental study, it can be concluded that RaCe multi-file rotary system may better be used in endodontic therapy, and the risk of microcracks in the tooth wall is less than that of NeoNiti single-file rotary system.

Prevalence of Lateral Radiolucency, Apical Root Resorption and Periapical Lesions in Portuguese Patients: A CBCT Cross-Sectional Study with a Worldwide Overview.

Objective:Apical periodontitis develops when bacteria, or their by products, migrate from the infected root canal system space to the surrounding apical tissues. The objective of the present multi-center cross-sectional study was to analyze the prevalence of lateral radiolucency, apical root resorption and periapical lesions in 7 districts of Portugal using cone-beam computed tomographic (CBCT) assessment.Methods:A total of 1,249 CBCT scans, from 11 dental clinics, were screened. Data regarding 22,899 teeth was included. For each tooth the recorded data was the presence of lateral radiolucency, apical root resorption, periapical lesions, previous root canal treatment, missed root canals, length of root canal filling (short, good or overfilling) and type of coronal restoration (intact tooth, non-restored, filling or crown). Differences between districts were tested using chi-squared. A P<0.05 was considered significant.Results:The proportion of lateral radiolucency ranged between 0.0% (Aveiro, Braga and Coimbra) and 0.9% (Lisbon), while the prevalence of apical root resorption ranged from 0.0% (Braga and Coimbra) to 3.0% in Setubal. The nationwide proportion of lateral radiolucency was 0.4%, while for apical root resorption was 1.1%. The prevalence of periapical lesions varied from 4.1% (Braga) and 13.0% (Lisbon) with a nationwide proportion of 10.0%. Significant differences were noted between districts (P<0.05).Conclusion:The prevalence of lateral radiolucency and apical root resorption were low in all districts. Root canal filled teeth were associated with higher periapical lesions proportions than non-treated teeth. Independently of the assessed district, the periapical status may be influenced by both quality of the endodontic treatment and coronal restoration.

A comparison between RVG and 2D and 3D measurements using cone-beam computed tomography to predetermine root canal lengths

A comparison between RVG and 2D and 3D measurements using cone-beam computed tomography to predetermine root canal lengths

The use of micro-computed tomography to determine the accuracy of electronic working length with two apex locators.

This study evaluated the precision of electronic working length by microcomputed tomography using two electronic apex locators (EALs). Twenty single-rooted permanent teeth without caries or restorations were selected as the subject teeth. The positions of the minor apical constriction (AC) and major apical foramen (AF) were measured by electronic root canal length, and microcomputed tomography was performed with the file inserted and fixed in the root canal. All teeth were measured individually and independently by two operators. The Mann-Whitney U-test was used to statistically test the AC and AF values using two EALs; P < 0.05 was defined as statistically significant. This was 65.0% within 1.5 mm in the case of two EALs on AC. This was more than 90.0% within 1.0 mm in the case of two EALs on AF. Comparison of the differences between the respective AC and AF of the measurements obtained using the two EALs revealed no significant difference. The two EALs are devices that can greatly improve the accuracy of WL control.

Micro-Computed Tomographic Analysis of the Shaping Ability of XP-Endo Shaper in Oval-Shaped Distal Root Canals of Mandibular Molars.

Objective:To compare the shaping ability of the XP-endo Shaper (XPS) system to the ProTaper Next (PTN) system in oval-shaped distal root canals.Methods:From 12 mandibular molars, distal roots with moderately curved single oval canals were randomly assorted to be instrumented with XPS (experimental group) or PTN (control group) and then scanned using micro-computed tomography [Scan 1]. The root canals of the XPS samples were prepared following the manufacturer's instructions using 15 insertions (XPS15) and rescanned [Scan 2]. An additional 10 insertions to the working length were applied, totalling 25 insertions (XPS25), and the roots were rescanned again [Scan 3]. PTN samples were prepared up to the X3 instrument (PTNX3) and rescanned [Scan 2]. The dentine removed and the unprepared areas were assessed. Data were analysed using a t-test with significance at α=0.05.Results:XPS25 was associated with a significantly greater dentine removal than XPS15 over the entire root canal length and in all three-thirds of the root canal (P<0.05). XPS25 significantly removed more dentine than PTNX3 in only the coronal third (P<0.05). XPS25 was also associated with a significantly smaller percentage of unprepared areas than XPS15 overall and in the coronal third (P<0.05). PTNX3 was associated with a significantly larger percentage of unprepared areas than XPS15 and XPS25 overall and in the coronal and middle thirds (P<0.05).Conclusion:Ten additional movements with XPS significantly improved instrumentation capacity, reducing the percentage of untouched surface areas but also removing more dentine.

A short review on the root canal configuration of primary maxillary molars

It is of interest to compile available information on the root canal morphology of primary maxillary molars from known literature. The literature resources used to collect data include Medline/PubMed, The Cochrane Central Register of Clinical Trials, SIGLE and Science Direct. Data consists of type of population, number of teeth per study, number of root canals, canal length and type of root canal configuration. We used data from a total of 13 studies (951 primary maxillary molars). Maxillary molars (1st and 2nd) are dominant for two roots variant. The first molar the mean root length ranges from 7.9mm - 8.1mm. The second molar ranges from 7.2mm-8.5mm. Type I (explain in a phrase) canal morphology is the common variant in both the molars. Data shows that Root Canal morphology shows variations with the diagnostic aid (example micro CT) used and in different ethnic populations.

Correlation of objective image quality and working length measurements in different CBCT machines: An ex vivo study

To investigate potential correlations between objective CBCT image parameters and accuracy in endodontic working length determination ex vivo. Contrast-to-noise ratio (CNR) and spatial resolution (SR) as fundamental objective image parameters were examined using specific phantoms in seven different CBCT machines. Seven experienced observers were instructed and calibrated. The order of the CBCTs was randomized for each observer and observation. To assess intra-operator reproducibility, the procedure was repeated within six weeks with a randomized order of CBCT images. Multivariate analysis (MANOVA) did not reveal any influence of the combined image quality factors CNR and SR on measurement accuracy. Inter-operator reproducibility as assessed between the two observations was poor, with a mean intra-class correlation (ICC) of 0.48 (95%-CI 0.38, 0.59) for observation No. 1. and 0.40 (95%-CI 0.30, 0.51) for observation No. 2. Intra-operator reproducibility pooled over all observers between both observations was only moderate, with a mean ICC of 0.58 (95%-CI 0.52 to 0.64). Within the limitations of the study, objective image quality measures and exposure parameters seem not to have a significant influence on accuracy in determining endodontic root canal lengths in CBCT scans. The main factor of variance is the observer.

Multifrequency Impedance Method Based on Neural Network for Root Canal Length Measurement

Root canal therapy is the most fundamental and effective approach for treating endodontics and periapicalitis. The length of the root canal must be accurately measured to clean the pathogenic substances in it. This study aims to present a multifrequency impedance method based on a neural network for root canal length measurement. A circuit system was designed which generates a current of frequencies from 100 Hz to 20 kHz in order to augment the data of impedance ratios with different combinations of frequencies. Several impedance ratios and other quantified characteristics, such as the type of tooth and file, were selected as features to train a neural network model that could predict the distance between the file and apical foramen. The model uses leave-one-out cross-validation, adopts the Adam optimizer and regularization, and has two hidden layers with nine and five nodes, respectively. The neural network-based multifrequency impedance method exhibits nearly 95% accuracy, compared with the dual-frequency impedance ratio method (which demonstrated no more than 85% accuracy in some situations). This method may eliminate the influence of human and environmental factors on measurement of the root canal length, thereby increasing measurement robustness.

Assessment of Postoperative Obturation Quality of Retreatment Cases - A Retrospective Study

Conventional endodontic therapy emphasizes many factors which mainly emphasize root canal disinfection.However there is a probability of endodontic therapy to give an unfavourable outcome such as persistentclinical symptoms and unfavourable periapical healing. The frequency of failure is reported to be around 20%and various factors contribute to it which mostly relies on the treatment procedure followed by the previousoperator. It is of paramount importance that postgraduate doctors should learn to treat these case scenarioswith high effectiveness. This study aims to assess the postoperative obturation quality of retreatment casesdone by graduate doctors. The study was done by using data collected from electronic medical records ofSaveetha Dental College, Chennai, India. The time frame of data collection was seen from June 2019 toMarch 2020. A total sample size of 230 was assessed radiographically and the quality of obturation wasanalyzed using 2 grading criteria in compliance with 2 operators. From the cases assessed, about 80% hadachieved correct radiographic length of obturation and about 70% of obturation was not of optimal quality.Quality of obturation was not adequate. The length of root canal filling was desirable whereas the quality ofcondensation was not adequate about 60% of the assessed cases

Influence of Root Canal Preparation on Formation of Dentinal Microcracks: A Systematic Review.

The effect of root canal preparation technique on microcrack initiation is a controversial issue. This systematic review aimed to assess the role of root canal preparation techniques with different kinematics (manual, rotary, reciprocating, adaptive, self-adjusting file) on microcrack initiation. In vitro and in situ studies comparing the influence of at least two different root canal preparation techniques on the initiation of dentin microcracks were searched in PubMed/MEDLINE and SCOPUS up to June 5, 2018 without language and period restriction. Two authors independently reviewed all identified titles and abstracts for eligibility. Tables were generated to summarize the included studies, and the included studies were assessed for bias. Fifty-four (n=54) articles met the eligibility criteria. The results were classified according to the method used for microcrack evaluation, and most studies that used micro-computed tomography showed no formation of new cracks after root canal preparation. In general, the instrumentation techniques induced microcrack formation when the methods were destructive, irrespective of kinematics. In relation to the apex region, when the preparation working length was set as the root canal length subtracted of 1 mm, the risk of microcrack initiation reduces. The majority of the included studies had low risk of bias for all assessed domains. Our results seem to indicate that the various root canal preparation techniques considered in this study will not cause damage to the dental structure when adequately employed and the proper methodology is applied.

A Comparative Evaluation of Effects of Conventional and Herbal Irrigants on Working Length Determination by Third Generation Apex Locator–An In Vitro Study

Abstract Introduction The establishment of accurate working length is one of the most critical steps in endodontic therapy from the biomechanical and obturation points of view. Traditionally, the use of radiography and tactile sense methods were used for working length estimation, but recently, the use of electronic apex locator (EAL) has come into existence. The aim was to evaluate the effect of conventional and herbal irrigants on working length determination by Root ZX. Materials and Methods A total of 110 extracted single rooted teeth were taken. Standard access cavities were prepared and samples were randomly divided into 11 groups (n = 10) according to the type of irrigating solutions used. The actual root canal length was measured, and the readings in dry conditions and wet conditions were recorded. The point where Root ZX showed beep was recorded and difference was recorded as well. The recorded data was calculated and statistically analyzed using unpaired t-test. Result In dry conditions, only saline, H2O2, Aloe vera, and green tea gave exact working length using apex locator values. Whereas in wet conditions, only Aloe vera and green tea gave exact working length. Conclusion Although the irrigants and dry conditions influenced the results, Root ZX can be considered to be accurate, and the difference was within the clinically acceptable range and not statistically significant.

Comparison Between Accuracy of Two Different Electronic Apex Locators in Determining Working Length of Root Canals: An In Vitro Study

Background: Accurate determination of the working length of root canals is an important factor for the success of endodontic therapy. Aim: Two different apex locators namely Propex Pixi (Dentsply) and Canal Pro (Coltene) are used to determine the working length of root canals and their results are compared to determine their accuracy. Material and Methods: Twenty extracted permanent single-rooted teeth are used for the study. To determine the working length of root canals of each tooth, two different types of electronic apex locators, Propex Pixi (Dentsply) and CanalPro (Coltene) are used and their results are compared. Result: There was a significant difference in accuracy between the two apex locators in determining the working length of root canals (p-value <0.05). Canal Pro was more accurate than Propex Pixi.

Assessment of Root and Root Canal Morphology of Human Primary Molars using CBCT

The purpose of this study is to evaluate the morphological characteristics of the roots and roots canals of primary molar teeth using Cone-Beam Computed Tomography (CBCT).&lt;br/&gt;A total of 68 CBCT images of children aged 4 - 5 years was used for this study. A total of 160 molar teeth were analyzed. Various parameters such as the number of roots and canals, length of root and root canal, and the angulation and shape of the roots were analyzed.&lt;br/&gt;All maxillary primary molars had 3 roots. The presence of 2 root canals in 1 root was only observed in the mesiobuccal root of maxillary primary second molars. Most mandibular primary molars had 2 roots, and most mesial roots had 2 root canals.&lt;br/&gt;Concerning the length of the roots, the palatal root of the maxillary primary molar was found to be longest whereas the distobuccal root was shortest. In mandibular primary molars, the mesial root was longer than the distal root. In maxillary primary molars, the palatal root had the greatest angulation whereas the distal root has the greatest in mandibular molars. The root and root canals of maxillary primary molars were more curved in shape whereas mandibular primary molars were straight.

A Comparative Evaluation of Four Different Techniques for Determining the Accuracy of Root Canal Working Length: An In Vitro Study

IntroductionComplete disinfection of root canal is one of the main objectives of root canal treatment. However, complete disinfection is only possible after correct determination of root canal working length. Thus, determining a correct working length is essential for endodontic success. Thus, the present study was conducted with the aim to comparatively evaluate the accuracy of four different techniques in determining root canal working length.Material and Methods30 freshly extracted human single-rooted teeth were taken. After sectioning the teeth at the cemento-enamel junction, K-Flexofile with size 10 was used to check the patency of canal and major foramen. Each sample was then subjected to all the four techniques. The four techniques used were conventional radiography, radivisiography, electronic apex locator (raypex 6) and cone beam-computed tomography. After calculating each root canal length of samples, their actual length was measured by using K- Flexofile until its tip became visible through the major foramen. The file was taken out when a magnifying glass showed its tip at the coronal border of major foramen. The adjustment of rubber stop was done according to the occlusal reference, and then the distance between the stop to the file tip was measured. Finally a comparison was done for each sample between the root canal length recorded with the four techniques and the actual length.ResultsMean of absolute differences with respect to actual length was lowest in case of electronic apex locator whereas, it was highest in case of cone beam-computed tomography. Conventional radiography and Radiovisiography had negative mean difference values that showed overestimated canal length. A significant difference was observed between cone beam-computed tomography and the other three techniques respectively (P < 0.05).ConclusionRaypex 6 apex locator was more accurate than the other three techniques in determining root canal working length.