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.

The usefulness of ultrasonography as a dynamic measurement system for visualizing root canal working length: an in vivo study.

OBJECTIVE: Although apex locators are generally effective tools for determining root canal working length, they may produce inaccurate results in some cases. The present study aimed to evaluate the efficacy of ultrasonography as an alternative method for measuring root canal length. MATERIALS AND METHODS: Forty-seven anterior teeth with apical lesions were selected for the study. Initially, an electronic apex locator was used to measure the working length. Subsequently, ultrasonography was employed to visualize the root apex and determine the working length. During ultrasound imaging, a K-file No. 15 was inserted into the root canal until its tip was visible on the ultrasound monitor. Measurements obtained from both methods were compared using an independent sample t-test. Correlations were assessed with the Pearson correlation coefficient, and agreement was determined using the Bland‒Altman plot. RESULTS: The mean working canal length was 19.9 mm for the apex locator and 20.6 mm for the ultrasonography-guided method. No significant differences were observed between the data obtained using the apex locator method and the data obtained using the ultrasonography guidance method. Furthermore, a high level of agreement was identified between the two techniques. CONCLUSION: Ultrasonography can be used to visualize the apex effectively and determine canal length, especially when canal length determination is uncertain for various reasons.

Population specific dental age estimation model for South Indian children based on normalized open apices method: A cross sectional study.

Age estimation plays significant role in forensic science especially when there is unavailability of the information concerned to the deceased. Use of population specific models of age estimation results in questionable evidence legally when tried on Indian children. The present study was designed to assess the accuracy of Cameriere's Italian and Balwant Rai Indian model on South Indian children and to derive and validate a novel model for south Indian children by considering a sample from a larger geographical area with a greater sample size of 2500. Accuracy of both the models for South Indian children was analysed using root mean square error. Significant differences were observed in estimated age across all age groups and between sexes, using above models. Root mean square error using Cameriere's Italian model was 1.54 and for Balwant Rai Indian model, it was found to be 1.78. The error for all the age groups was found to be 1.49 to 1.60 using Cameriere's model and 1.41 to 2.1 using Rai's model. A novel Population specific model was derived based on open apices of left mandibular seven teeth. Root mean square error with novel derived Population specific model was found to be less than 1 year overall being 0.94 and for all the age groups ranged from 0.91 to 0.96. The derived Population specific model exhibits superior accuracy compared to both the models and hence it can be considered for dental age estimation of the south Indian children in medico-legal cases.

Evaluation of Mental Foramen and Mandibular Canal Course and Location in an Emirati Subpopulation.

INTRODUCTION AND AIMS: Violations of the mandibular canal (MC) and mental foramen (MF) and subsequent injuries to their neurovascular bundle have been reported after surgical and nonsurgical dental procedures. Besides using advanced technologies such as cone-beam computed tomography (CBCT), clinicians should be aware of the anatomy and location of MC and MF in different populations. This study aims to describe the morphologic characteristics of the MF, MC, and its intrabony location in relation to the apices of mandibular posterior teeth in an Emirati subpopulation using CBCT. METHODS: A total of 3700 CBCT scans were screened, and 154 scans that met the inclusion and exclusion criteria were randomly selected. The scans were assessed using 3-dimensional multiplanar imaging for the following structures: the location of MF and the MC course, its intrabony location, and its relationship to the apices of the mandibular posterior teeth. The data were analysed statistically using SPSS software. RESULTS: The MC ran lingually and inferiorly at the posterior region and became more buccal and superior towards the MF. The distal root of the mandibular second molar was found to be the closest root to the MC (2.06 ± 1.83 mm). Moreover, the most common location of the MF was distal to the contact area between the 2 premolars (0.83 ± 1.84 mm) with a significant negative correlation to age (with and increase in age, the MF moves distally). The distance between the root apices and the MC was statistically significantly affected by age (positive correlation) and gender (male patients had a greater distance). CONCLUSIONS: The common course of the MC is lingual and inferior posteriorly and becomes more buccal and superior towards the MF, which is located mostly between the mandibular first and second premolars. Furthermore, the distal root of the mandibular second molar is the closest to the MC and has a positive relationship with age.

Mental foramen and apical foramen: A dangerous anatomical proximity.

The study evaluated the spatial position of the mental foramen (MF) using 300 cone-beam computed tomography. The spatial position was analyzed with the horizontal location and relative location (distance between apical foramen and MF). The horizontal location was assessed through three positions (positions 1, 2, and 3). The relative location was determined with the x, y, and x coordinates of the root apex of mandibular premolars and the MF. Student's t-test and chi-square were performed. The most common horizontal location (52%) was position 2, which means between the premolars (p < 0.05). The relative location of the MF to the root apex of the second premolar was closer than the first premolar (p < 0.05). The distance between the root tip of the second premolar and the MF was 5.27 mm, with a minimum value of 1.87 mm. Clinicians should be aware of the possible neural results to the mental nerve of an endodontic infection and the extrusion of irrigation solutions.

Efficacy of electronic apex locators in comparison with intraoral radiographs in working length determination- a systematic review and meta-analysis.

BACKGROUND: Successful endodontic treatment needs accurate determination of working length (WL). Electronic apex locators (EALs) were presented as an alternative to radiographic methods; and since then, they have evolved and gained popularity in the determination of WL. However, there is insufficient evidence on the post-operative pain, adequacy, and accuracy of EALs in determining WL. OBJECTIVE: The systematic review and meta-analysis aims to gather evidence regarding the effectiveness of EALs for WL determination when compared to different imaging techniques along with postoperative pain associated with WL determination, the number of radiographs taken during the procedure, the time taken, and the adverse effects. METHODS: For the review, clinical studies with cross-over and parallel-arm randomized controlled trials (RCTs) were searched in seven electronic databases, followed by cross-referencing of the selected studies and related research synthesis. Risk of bias (RoB) assessment was carried out with Cochrane's RoB tool and a random-effects model was used. The meta-analysis was performed with the RevMan software 5.4.1. RESULTS: Eleven eligible RCTs were incorporated into the review and eight RCTs into the meta-analysis, of which five had high RoB and the remaining six had unclear RoB. Following meta-analysis, no significant difference in postoperative pain was found among the EAL and radiograph groups (SMD 0.00, CI .29 to .28, 354 participants; P value = 0.98). Radiograph group showed better WL accuracy (SMD 0.55, CI .11 to .99, 254 participants; P value = 0.02), while the EAL group had 10% better WL adequacy (RR 1.10, CI 1.03-1.18, 573 participants; P value = 0.006). CONCLUSION: We found very low-certainty evidence to support the efficacy of different types of EAL compared to radiography for the outcomes tested. We were unable to reach any conclusions about the superiority of any type of EAL. Well-planned RCTs need to be conducted by standardizing the outcomes and outcome measurement methods.

Influence of root shape on canal complexity at the mandibular molar apical surgical resection level: A micro-CT study.

OBJECTIVES: This study aimed to investigate the relationship between the aspect ratios of mandibular molar roots at the apical 3-mm level and their root canal complexity. DESIGN: This study used micro-CT imaging to analyze 163 two-rooted mandibular molars. The aspect ratios of the roots at the apical 3-mm level were categorized as "< 2.75" or "≥ 2.75" (mesial) and "< 1.75" or "≥ 1.75" (distal). A two-dimensional (2D) analysis focused on four apical axial cross-section levels to determine the presence of main and accessory canals and isthmus. Additionally, a three-dimensional (3D) assessment of the apical 4-mm of both roots examined main and accessory canals, apical foramina, apical deltas, and middle mesial canals. RESULTS: Mesial roots with aspect ratios ≥ 2.75 showed a higher number of main canals at all levels compared to those with aspect ratios < 2.75 at the 3-mm level. Additionally, the ≥ 2.75 group exhibited more accessory canals and a higher average number of accessory canals. The 3D assessment confirmed significantly more accessory canals and apical foramina in the ≥ 2.75 group. The prevalence of roots with apical deltas was nearly double in the ≥ 2.75 group, and middle mesial canals were exclusively found in this group. In the distal root, the ≥ 1.75 group showed a significantly higher number of main canals at all axial levels. No significant differences were observed between groups in terms of accessory canals, apical foramina, or deltas. CONCLUSIONS: A higher root aspect ratio is related to higher anatomical complexity.

Anatomic relationship between the root apex of maxillary molars and maxillary sinus in the presence of antagonist teeth: A Kwak's method with divisions.

OBJECTIVE: The purpose of the study was to evaluate the proximity between the root apices of maxillary molars and maxillary sinus floor using cone-beam computed tomography (CBCT) in the southern Turkish subpopulation. DESIGN: For the study, 246 CBCT images were analyzed. The absence of antagonist teeth was excluded. Kwak's types III and V were detailed with three divisions. Division M; the penetration of the mesial root only, Division D; the penetration of the distal root only, and Division MD; the penetration of both buccal roots. The distance between the maxillary sinus and the root apices was measured. Student's t-test, one-way ANOVA, and chi-square were used for statistical analysis. RESULTS: The penetration of maxillary molars was 24.40%. The highest prevalence belonging to Type I. Division MD was 44.35% for Type III and 40.42% for Type V. Division M was higher than Division D. The distances between the sinus and root apices were 1.35-2.41 mm in Type I. The distance decreased with age (p < 0.05). CONCLUSION: Both buccal root penetration into the sinus was higher than the single root penetration. The distance of the second molar root apices to the sinus was closer than the first molar. One-quarter of the first and second molars were inside the sinus. A greater likelihood of penetration of the root apices into the sinus with increased age.

A Global Overview on Electronic Apex Locator Use From 1968 to 2023: A Bibliometric Analysis.

INTRODUCTION: This bibliometric review analyzed the research trends and main characteristics of articles related to Electronic Apex Locators (EALs). METHODS: The search was conducted in November 2023 on the Web of Science Core Collection. Narrative and systematic reviews, observational and intervention studies, laboratory, and clinical studies were included. Two researchers selected the articles and extracted the number of citations, year of publication, journal, study design, theme, country, continent, institutions, author, and keywords. Collaborative networks were generated using the VOSviewer software. The relationship between data were determined by Spearman's correlation. RESULTS: The search resulted in 374 articles, of which 294 were included. Most cited article had 175 citations. The most prevalent journal was the Journal of Endodontics (n = 84). The predominant study design was the laboratory-based (n = 223). The predominant theme was the EALs accuracy (n = 175). Piasecki L was the author with the highest number of articles (n = 11). Only 8.16% of the studies were conducted in deciduous teeth. The country with the most studies was Brazil (n = 46). Asia (n = 107) was the continent with the highest number of publications. There was a weak positive correlation between the number of citations and impact factor (rho = .294), and a strong negative correlation between citations and year of publication (rho = -.710). CONCLUSIONS: The majority of articles were laboratory-based studies conducted on permanent teeth, focusing on the accuracy of EALs. Future studies should prioritize research on deciduous teeth, systematic reviews, and, notably, clinical trials.

An Ex-Vivo Study Comparing the Accuracy of the E-Connect S+ and Morita Tri Auto ZX2+ Endodontic Handpieces in Root Canal Length Determination.

INTRODUCTION: This ex vivo study evaluated the accuracy of the Electronic Apex Locator (EAL) and Automatic Apical Stop (AAS) functions of the E-Connect S+ and Morita Tri Auto ZX2+ cordless apex locators in determining patency length. METHODS: Sixty-four human teeth with a single root were randomly allocated into E-connect or Morita groups (n = 32). The canals were accessed and preflared, after which a size 15 K-file was inserted into the canal to the major foramen and recorded as the actual length (AL). Matched measurements were taken using the AAS and EAL functions and visually confirmed with confocal microscopy. The variance between canal length (mm), the persons correlation (ρ) between function and AL, and the accuracy (%) of the canal length relative to the AL (Δmm) between devices and functions were assessed. RESULTS: Regardless of device or function, all measurements were within 1±Δmm and correlated strongly (ρ > 0.97) with the AL. When considering a more stringent clinically acceptable range of 0.5±Δmm from the AL, all devices and functions demonstrated similar accuracy levels (84%-94%). However, at lower tolerance ranges, the E-connect device with the EAL function exhibited the highest accuracy. On average, all devices and functions stopped short of the AL (mean Δmm>0). CONCLUSION: The E-Connect S+ and Morita Tri Auto ZX2+ apex locators provided reliable accuracy in determining the position of the major foramen. These findings demonstrate a high level of reproducibility in canal length measurements using both cordless endodontic handpieces, regardless of whether the EAL or AAS functions were employed.

Morphology of the Physiological Foramen: II. Maxillary and Mandibular Premolars.

INTRODUCTION: Information concerning the anatomy of the physiological foramen is still limited. The aim of this study was to investigate the distance between the physiological and anatomic apex, the shape and diameter of the physiological foramen in maxillary (Mx) and mandibular premolars (Mn). METHODS: The anatomy of the apex of 229 maxillary (first: MxP1; second: MxP2) and 221 mandibular premolars (first: MnP1; second: MnP2) from a mixed Swiss-German population was investigated by means of microcomputed tomography and 3-dimensional software imaging. RESULTS: The following results were obtained in the presence of a main physiological foramen. 1. The distance between the physiological and anatomic foramen was 0.29-0.99 mm (MxP1), 0.21-1.03 mm (MxP2), 0.13-0.8 (MnP1), and 0.15-1.41 (MnP2). 2. The mean narrow and wide diameters of the physiological foramen were 0.19-0.33 mm (MxP1), 0.25-0.42 mm (MxP2), 0.28-0.37 (MnP1), and 0.28-0.40 (MnP2). 3. The most common physiological foramen shape was oval (66.7% MxP1, 89.7% MxP2, 91.8% MnP1, 64.4% MnP2). CONCLUSION: Considering the recommended preparation sizes based on a size corresponding to the friction, that is at the narrowest point in the area of the apical constriction (physiological foramen), and within the limitations of this ex vivo microcomputed tomography study, a final preparation size could be chosen when considering the pertaining morphologic considerations; yet, to a minimum ISO 30 size.

How Does Intentional Apical Foraminal Enlargement Affect the Foramen and Root Canal Morphology?

INTRODUCTION: This study assessed the effect of intentional foraminal enlargement on the foramen and the apical root canal morphology. METHOD: Sixty mesial roots of mandibular molars were scanned by micro-computed tomography. Their apical foramina were photographed with a stereomicroscope before and after preparation. Three groups were formed (n = 20) according to the working length (WL). G-1: foramen - 1 mm; G0: foramen; and G+1: foramen + 1 mm. Each group originated 2 subgroups (n = 10): G-1: Buchanan's patency (size 10 K-type file) and foraminal debridement (sizes 20, 25 and 30 K-type files); G0 and G+1: rotary foraminal enlargement (ProDesign S size 25/.08) or reciprocating foraminal enlargement (R25). The area, perimeter, transportation, and noninstrumented walls of the foramen were evaluated. The root canal transportation and the centering index of preparation at 1, 3 and 5 mm from the foramen were also assessed. Data were compared statistically (α = 5%). RESULTS: The instruments used at the foramen and 1 mm beyond promoted foraminal enlargement and transportation. Regarding NIW, there was no difference between mechanized foraminal enlargements performed at the foramen or 1 mm beyond, similar to the manual foraminal debridement group (P > .05). There was no difference in transportation and centralization at 1-, 3-, and 5-mm apical levels, regardless of the instrumentation systems. CONCLUSION: Mechanical preparation at the foramen, or 1 mm beyond, resulted in foraminal enlargement, transportation and were not able to touch all root canal walls that delimit the foramen.

Measurement of the apical anatomy of immature maxillary central incisors using cone-beam computed tomography.

OBJECTIVE: To investigate the CBCT findings of the apical anatomy of immature maxillary central incisors. METHODS: CBCT images of 100 immature maxillary central incisors in Nolla 8 and 100 immature maxillary central incisors in Nolla 9 were collected. The mesiodistal and carniocaudal diameters of the apical foramen of immature maxillary central incisors were measured by software included with CBCT, as well as the mesiodistal, carniocaudal and facioligual diameters of the apical shadow. The apical shadow and apical foramen diameters were compared between Nolla 8 and Nolla 9. Data were analyzed using the MedCalc software package. RESULTS: For immature maxillary central incisors, the mesiodistal and facioligual diameters of the apical foramen were 2.75±0.68 mm and 3.28±0.74 mm in Nolla 8 and 1.50±0.51 mm and 1.92±0.79 mm in Nolla 9. The mesiodistal, facioligual and carniocaudal diameters of the apical shadow were 3.84±0.73 mm, 4.49±0.68 mm and 3.41±1.27 mm in Nolla 8 and 2.76±0.60 mm, 3.41±0.80 mm and 2.06±0.65 mm in Nolla 9, respectively. CONCLUSIONS: The immature maxillary central incisors in Nolla 8 have a larger apical shadow and apical foramen than those in Nolla 9. The apical region of the maxillary central incisors in Nolla 8 was more likely to have a broad, blurred lamina dura. With the development of the apical foramen, the lamina dura in the apical region tended to be clear and sharp. CLINICAL SIGNIFICANCE: To our knowledge, this is the first study to radiologically analyse the in vivo anatomy of the apical foramen and apical shadow of immature maxillary central incisors. The results of this study provide a more detailed understanding of the apical anatomy of the immature maxillary central incisor for the diagnosis and treatment of apical lesions.

Relación entre el seno maxilar y ápices de dientes postero- superiores con tomografía computarizada de haz cónico / Relationship between the maxillary sinus and apices of posterior-superior teeth using cone beam computed tomography

El conocimiento de la relación entre el seno maxilar y los ápices de los dientes posterosuperiores es fundamental para evitar complicaciones frente a distintos tratamientos. Estudio descriptivo de corte transversal, con muestra por conveniencia de 383 imágenes de raíces de dientes posterosuperiores obtenidas por medio de tomografía computarizada de haz cónico (TCHC) de un centro radiológico en Viña del Mar, Chile. Cada raíz fue clasificada según su relación vertical con el seno en 4 categorías (0: ápice no se encuentra en contacto con contorno inferior del seno; 1: ápice en contacto con seno; 2: ápice lateralmente al seno; 3: ápice se protruye en seno). Además se midió su distancia en mm. Los datos fueron analizados con estadística descriptivas. El diente más lejano al seno maxilar fue el primer premolar superior (4.2 mm), seguido por el segundo premolar superior (1 mm). En el primer molar superior la raíz más lejana fue la mesio-vestibular (MV) 1mm, seguida por la raíz disto-vestibular (DV) 0.6mm y la raíz palatina (P) -1mm. En el segundo molar superior la raíz más lejana fue P 0.4mm, luego la DV 0.3mm, y MV -0,11mm. En cuanto a las categorías, se observó que la mayoría de las raíces se encuentran alejadas del seno siendo la raíz P del primer molar superior y la raíz MV del segundo molar superior las que se encuentran mayormente protruidas (42 % y 26 % respectivamente). El primer premolar es el diente posterosuperior que se encuentra más alejado del seno maxilar y a medida que se avanza hacia posterior hay tendencia a disminuir la distancia entre los ápices y el seno maxilar.

SUMMARY: Knowledge of the relationship between the maxillary sinus and the apices of the upper posterior teeth is crucial to avoid complications when considering different treatments. A descriptive cross-sectional study was carried out, with a convenience sample of 383 images of upper posterior teeth roots, obtained by means of cone beam computed tomography (CBCT) from a radiological center in Viña del Mar, Chile. Each root was classified according to its vertical relationship with the sinus into 4 categories (0: apex is not in contact with the lower contour of the sinus; 1: apex is in contact with the sinus; 2: apex laterally to the sinus; 3: apex protrudes in sinus). In addition, its distance was measured in mm. The data were analyzed with descriptive statistics. The tooth farthest from the maxillary sinus was the maxillary first premolar (4.2 mm), followed by the maxillary second premolar (1 mm). In the upper first molar, the most distant root was the mesiobuccal (MV) 1mm, followed by the distobuccal root (DV) 0.6mm and the palatal root (P) -1mm. In the upper second molar, the furthest root was P 0.4mm, then DV 0.3mm, and MV -0.11mm. In reference to the categories, it was observed that most of the roots are far from the sinus, with the P root of the first upper molar and the MV root of the second upper molar being the most protruding (42 % and 26 % respectively). The first premolar is the posterior maxillary tooth that is furthest from the maxillary sinus and as one advances posteriorly there is a tendency to decrease the distance between the apices and the maxillary sinus.

Variations in the morphology of apical constriction affecting electronic readings: An in vitro investigation using 3D-printed tooth models.

We investigated the interference of apical constriction position and diameter on the accuracy of electronic apex locators using 3D-printed tooth models. Single-rooted tooth models with the same length, canal taper and major foramen, but variation in apical constriction position or size, were designed and 3D-printed. A mounting model was custom-made for precise measurement of both marks (0.5 and APEX/0.0) of two electronic apex locators. The electronic measurements of both devices were correlated significantly to the major foramen rather than apical constriction. The mean measurements of the group with 0.45 mm in apical constriction width were significantly shorter than those of the other groups for both marks of the two devices (p < 0.05). The variations in apical constriction position and width negatively affected the precision of the 0.5 mark of the tested devices. The 0.0 or APEX mark was consistently located the major foramen.

Working length variation during multiple-visit endodontic treatment: An observational study.

This study investigated variation in working length during multiple-visit endodontic treatment. Patients (N = 106) with pulpitis or pulp necrosis, with or without apical periodontitis, were included. During the first appointment, glide path was performed with ProGlider and shaping with ProTaper Next. Working length was detected four times. Working length was then re-recorded prior to filling during the second appointment and a 0.5 mm threshold was selected as the minimum clinically meaningful variation. A logistic regression model was used to evaluate the impact of tooth anatomy, preoperative pulp status, apical periodontitis and lesions of endodontic origin on working length variation. Working length varied between first and second appointments in 34% of patients. The presence of apical periodontitis was the only variable significantly associated with variation in working length (p = 0.011). These data suggest that working length should be re-checked prior to root canal filling to prevent procedural errors.

Internal morphology of distal roots of mandibular first molars revealed by computed microtomography.

To evaluate the internal morphology of 100 distal roots of mandibular first molars using micro-CT. Teeth were scanned to characterise: Vertucci type, root length, canal shape, presence and location of accessory canals, and the number of foramina at 4 mm from the apex, presence of root isthmus and the length from the primary canal to the apical foramen. Vertucci type I was found in 57% of cases, followed by V (27%). The most common cross-section 1 mm from the apex was oval (49%) and circular (38%). The average root length was 16.06 mm (16.61-19.02 mm). The mean foramen size was 0.32 and 0.53 mm for the minor and major diameters, respectively. The volume, surface area and SMI were 7.84 mm3 , 68.87 mm2 and 1.52 mm, respectively. Root isthmi were found in 47% of the samples, and the length mean from the primary canal to the apical foramen was 2,03 mm. The internal morphology of the distal roots of mandibular first molars may be complex and shows variations.

Evaluation of Different Techniques of Working Length Determination in Comparison with CBCT.

AIM: To estimate the working length of teeth using conventional tactile technique, radiovisiography technique, Apex locator, and confirmation of working length by cone beam computed tomography technique. MATERIALS AND METHODS: Forty patients with the age group between 20 and 50 years with irreversible pulpitis were included in this study. After taking a preoperative radiograph, the procedure was started. The cavity wall buildup was done using composite in the cases needed and then rubber dam application was done. The working length of mesiobuccal and mesiolingual canal was taken using cone beam computed tomography and this was considered as the standard value. Then using tactile method, length of the canal was measured using radiovisiographic software followed by apexlocator. RESULT: The Apex locator has showed best result as compared to tactile and radiovisiography. CONCLUSION: Apex locator values were closest to cone beam computed tomography working length measurement values and electronic apexlocator can be used efficiently as an alternative method for working length determination. The quality of various techniques according to ranks of working length determination was found to be Cone beam computed tomography (CBCT) > Apexloc > Radiovisiography (RVG) > Tactile. Thus, Apex locator can be used as an alternative to cone beam computed tomography for working length determination.

Panoramic radiography and cone-beam computed tomography to measure distances between root apexes and anatomical structures / Radiografía panorámica y tomografía computarizada de haz cónico para medir distancias entre ápices radiculares y estructuras anatómicas

Aim: To compare the accuracy of the panoramic radiography with cone-beam computed tomography (CBCT) scans in measuring the distances between root apexes and the adjacent anatomical structures including the maxillary sinus and the mandibular canal. Material and Methods: A total of 200 CBCT scans (100 maxillary and 100 mandibular) from patients who also had corresponding panoramic radiography were selected. Linear measurements (in mm) presenting centralized image were made between the apexes of the maxillary teeth and the inferior wall of the maxillary sinus, and between the apexes of the mandibular teeth and the superior border of the mandibular canal by using specific software for panoramic radiography and the measurements on the coronal sections in CBCT scans. Data were submitted to inferential statistical analysis and Student's t-test for comparison between measurements. Results: CBCT scans were significantly more accurate than panoramic radiography to measure the distances between the apexes of the maxillary teeth and the inferior wall of the maxillary sinus (p<0.05) and between the apexes of the mandibular teeth and the superior border of the mandibular canal or mental foramen (p<0.05). Conclusion: CBCT scans present more accurate measurements than panoramic radiography.

Objetivo: Comparar la precisión de la radiografía panorámica con las exploraciones de la tomografía computarizada dental de haz en cónico (CBCT) para medir las distancias entre los vértices radiculares y las estructuras anatómicas adyacentes, incluidos el seno maxilar y el canal mandibular. Material y Métodos: Se seleccionaron un total de 200 tomografías CBCT (100 maxilares y 100 mandibulares) de pacientes que además tenían la correspondiente radiografía panorámica. Se realizaron mediciones lineales (en mm) que presentaban imagen centralizada entre los ápices de los dientes maxilares y la pared inferior del seno maxilar, y entre los ápices de los dientes mandibulares y el borde superior del canal mandibular mediante software específico para radiografía panorámica. y las mediciones en las secciones coronales en escaneos CBCT. Los datos se sometieron a análisis estadístico inferencial y prueba t de Student para comparación entre mediciones. Resultados: Las exploraciones CBCT fueron significativamente más precisas que la radiografía panorámica para medir las distancias entre los ápices de los dientes maxilares y la pared inferior del seno maxilar (p<0,05) y entre los ápices de los dientes mandibulares y el borde superior de los dientes mandibulares. canal o agujero mentoniano (p<0.05). Conclusión: Las exploraciones CBCT presentan mediciones más precisas que la radiografía panorámica.

Evaluación radiográfica de 5000 tratamientos endodónticos realizados en premolares y molares mandibulares y maxilares en una población en Argentina / Radiographic evaluation of 5000 endodontic treatments performed on mandibular and maxillary premolars and molars in a population in Argentina

Objetivo: Evaluar radiográficamente tratamientos en- dodónticos del sector posterior de la cavidad bucal y com- parar la frecuencia de aceptabilidad en cada pieza dentaria involucrada. Materiales y métodos: Se evaluaron 5000 radiogra- fías de archivo de tratamientos endodónticos realizados apro- ximadamente entre 2005 y 2019 en premolares y molares mandibulares y maxilares en Argentina. Se consideraron tratamientos correctos e incorrectos de acuerdo con: 1) con- formación de la preparación quirúrgica; 2) límite apical de la obturación; 3) homogeneidad de la obturación. Se obtuvo la fre- cuencia absoluta y relativa de correctos e incorrectos. El aná- lisis entre frecuencias y pieza dentaria se realizó con la prueba de chi cuadrado y el cálculo del coeficiente V de Cramer. Para la comparación entre grupos de piezas dentarias se utilizó la partición del valor de chi cuadrado obtenido en los corres- pondientes grados de libertad. Nivel de significación P <0.05. Resultados: La partición del valor de chi cuadrado no mostró diferencias significativas entre primeros y segundos premolares mandibulares. Las otras comparaciones exhibie- ron diferencias significativas. Conclusiones: Un alto porcentaje de los tratamientos endodónticos de la población estudiada tiene por lo menos una condición que permite categorizarlos como incorrectos según el criterio establecido en este trabajo. Este porcentaje es más preponderante en anatomías complejas (AU)

Aim: To evaluate radiographically endodontic treat- ments performed in the posterior area of the oral cavity and compare the frequency of acceptability in each tooth involved. Materials and methods: 5,000 archival radiographs of endodontic treatments performed between 2005 and 2019 on mandibular and maxillary premolars and molars in Argentina were evaluated. The percentages of correct and incorrect treatments were considered according to 1) shaping of the preparation; 2) apical limit of the obturation; 3) homogeneity of the obturation. The absolute and relative frequencies of correct and incorrect treatments were calcu- lated. The association between these frequencies and tooth type was analyzed using the chi-square test and Cramer's V coefficient. For the comparison between groups of teeth, the partition of the chi-square value obtained in the corre- sponding degrees of freedom was used. Level of significance was P <0.05. Results: The partition of the chi-square value did not show a significant difference between the first and second lower premolars. The differences were significant in the other comparisons. Conclusions: A high percentage of the endodontic treat- ments in the study population have at least one condition war- ranting their classification as incorrect according to the crite- ria established in this study. This percentage is more prevalent in complex anatomies (AU)