Analysis of Fused Rooted Maxillary First and Second Molars with Merged and C-shaped Canal Configurations: Prevalence,Characteristics, and Correlations in a Saudi Arabian Population

IntroductionThe aims of this in vivo cone-beam computed tomographic (CBCT) study were to evaluate the prevalence, characteristics, and correlations between the fused rooted maxillary first and second molars as well as their consequent merged and C-shaped canals in a Saudi Arabian population.MethodsCBCT imaging of 726 maxillary first and second molars from 208 subjects of Saudi origin were evaluated in the present study. The prevalence of fused rooted maxillary molars, merged canals, C-shaped configurations, and correlations between the presence of fused rooted teeth between first and second molars were examined as the primary outcome. Differences by sex, location in the jaw, and bilateral symmetry (similarity between right- and left-side teeth in the same patient) were evaluated as the secondary outcome. The Z test was used for differences in the independent proportions, the chi-square test was used for differences between sex and locations, and the Cohen kappa test was used for bilateral symmetry. The kappa test was also used for intrarater reliability. A value of P < .05 was considered significant.ResultsThe prevalence of fused rooted maxillary first and second molars was 7% and 21%, respectively. Within fused rooted teeth, the presence of merged canals was 8.3% and 32.1%, whereas the prevalence of C-shaped canals was 8.3% and 5.1% in first and second maxillary molars, respectively. Among 57 subjects who had fused rooted maxillary molars, 19.3% showed a correlation between first and second molars. In fused rooted maxillary molars, 3.8% first molars and 13% second molars were bilaterally symmetrical. There were no statistically significant differences between sexes and right- and left-sided fused rooted maxillary molars, merged canals, or C-shaped canals.ConclusionsMaxillary second molars presented more complex external and internal morphology compared with maxillary first molars, with an overall prevalence of 14% of fused rooted maxillary molars and 3.7% merged and 0.8% C-shaped canal configurations for all maxillary molars. The clinician should be aware of such challenges, and for a better treatment outcome, the use of CBCT imaging (small field of view) and an operative dental microscope can be considered when a preoperative periapical radiograph shows signs of fused rooted maxillary molars.     

Symmetry of root anatomy and root canal morphology in maxillary premolars analyzed using cone-beam computed tomography

ObjectiveThis study aimed to use cone-beam computed tomography (CBCT) to evaluate the root anatomy and canal morphology of maxillary premolars in a Chinese population and determine their degree of bilateral symmetry.Design774 CBCT images were retrospectively analyzed, representing 1387 maxillary first premolars and 1403 second premolars. The number of roots and canals were recorded. The morphology of root canal systems was determined according to Vertucci’s classification. The symmetry of root and canal anatomies between maxillary contralateral premolars was further evaluated.ResultsThe most common anatomy of maxillary first and second premolars was one-rooted with two canals (58.0%) and one-rooted with one canal (50.3%), respectively. The typical canal morphology was type IV (42.7%) in maxillary first premolars and type I (50.3%) in maxillary second premolars. One-rooted maxillary premolars exhibited a higher variability in the canal morphology, compared to two-rooted or three-rooted teeth. Maxillary second premolars exhibited greater anatomic symmetry than first premolars. The root and canal numbers showed bilateral symmetry between 80.2% of maxillary first premolar pairs and 81.8% of second premolar pairs. Bilateral symmetry in both number and morphology of roots and canals was observed for 72.3% of maxillary first premolar pairs and 73.2% of second premolar pairs.ConclusionThe root anatomy and canal morphology of maxillary premolars in a Chinese population were quite diversified. Maxillary contralateral premolars demonstrated a high degree of symmetry in root and canal anatomies, which enables practitioners to better determine the nature of the root canal system during treatment of opposite homonymous teeth.     

CBCT study of root and canal morphology of permanent mandibular incisors in a Chinese population

Objective. To evaluate root canal morphology of permanent mandibular incisor teeth in a Chinese population using cone-beam computed tomography (CBCT). Materials and methods. CBCT images of Chinese patients were collected and 1553 permanent mandibular incisors in the images were included. The following observations on the included teeth were to determine the number of roots, root morphology and canal configuration. The root canal configurations were classified. The effect of gender on the incidence of the second canal was investigated. Results. Of permanent mandibular incisors, 86.8% had a single root with single canal. Mandibular lateral incisors (17.5%) had a higher incidence of a second canal compared with mandibular central incisors (8.9%) (p = 0.000). A slightly higher percentage of incidence of a second canal was found in males (14.6%) than in females (11.9%) (p = 0.129). Conclusions. Permanent mandibular incisors with two canals had a relatively low incidence in this Chinese population. The incidence of a second canal did not differ between males and females. CBCT is a valuable aid during root canal treatment.     

Analisi alla Cone Beam Computed Tomography della simmetria anatomica in molari superiori ed inferiori

AimTo analyze the symmetry in root canal configurations in the maxillary and mandibular permanent molar teeth of a Caucasian population using Cone Beam Computed Tomography (CBCT).ResultsOf 45 patients who had both maxillary first molars, 32 (71.1%) had perfect symmetry in the root and canal morphology of homonym teeth on the opposite side. As regards the maxillary second molars, the symmetry was observed in 43 patients (79.6%) of 54. Of 34 patients who had both mandibular first molars, 24 (70.6%) showed a perfect symmetry in the root and canal morphology of homonym teeth on the opposite side. As regards the mandibular second molars, the symmetry was observed in 47 patients (81%) of 58.ConclusionsCBCT is an exciting and clinically useful tool in studying root canal morphology and so the symmetry between homonym teeth.     

Characteristics of premaxillary supernumerary teeth in primary and mixed dentitions: a retrospective analysis of 212 cases

Abstract Aim: To investigate the characteristics and distribution of premaxillary supernumerary teeth affecting primary and mixed dentitions in Indian children. Methods: This retrospective analysis included 11 200 children, aged 3–12 years, who attended a pediatric dental clinic for dental care during the period 2007–2010. The children were divided into group I (aged 3–6 years) and group II (aged 7–12 years), and data regarding maxillary anterior supernumerary teeth, diagnosed both as isolated and/or as unexpected findings during routine clinical and radiological examinations, were gathered. Pearson’s χ²‐test, with a 0.05 level of significance, was used for the analysis. Results: The overall prevalence of premaxillary supernumerary teeth in primary and mixed dentitions was 1.9%. Single supernumerary teeth (84.9%) and conical morphology (68.7%) were commonly seen in both groups. The most common sagittal position was palatal (92.3%) among both erupted and impacted maxillary anterior supernumerary teeth. Conclusion: The prevalence of premaxillary supernumerary teeth in Indian children found in this study was 1.9%, with an overall male to female ratio of 1.7:1. Single supernumerary teeth, conical morphology, and erupted supernumerary teeth were the most commonly seen. Supernumerary teeth associated with clinical complications were relatively low (48%), and axial rotation or displacement of maxillary incisors was the most common sequelae.     

A cone-beam computed tomography study of root canal morphology of maxillary and mandibular premolars in a Turkish population

Aim. The aim of this study was to evaluate the root canal number and configuration of maxillary and mandibular premolar teeth by gender, intervals for decades, tooth position and unilateral or bilateral occurrence in a Turkish population using Cone Beam Computed Tomography(CBCT) scanning. Methodology. CBCT images of 5496 maxillary and mandibular premolars from 849 patients were evaluated. The following was evaluated in all the images: numbers of roots and root canals, the morphology of the root canal configuration according to the Vertucci classification, male–female differences in the tooth position and male–female differences in unilateral or bilateral occurrence. The reliability data were analyzed with a chi-square test. Results. The most prevalent root canal frequency was the two canals (86.2%) and type IV (76.9%) configuration for maxillary first premolar, one canal (59.7%) and type I (54.5%) canal configuration for second premolar. The incidence of one canal was higher in females and the occurrence of two or three canals was more common in males. The incidence of one canal was higher on the left side of maxillary premolars and the incidence of two canals was higher on the right side. Most mandibular first (93.5%) and second (98.5%) premolars had one canal. In general, females had one root canal of the mandibular premolar, whereas males had two or three canals. The type I configuration was most common and the incidence was higher on the right side. There were some differences found in the frequency distribution of the number of root canals and configuration of maxillary and mandibular premolar teeth according to intervals for decades. Conclusion. CBCT scanning provides comprehensive information about the root canal morphology of maxillary and mandibular premolar teeth. These data may help clinicians in root canal treatment of premolar teeth.     

Prevalence of maxillary lateral incisor agenesis and associated skeletal characteristics in an orthodontic patient population

Objectives: This study was aimed to investigate the prevalence of maxillary lateral incisor agenesis and associated skeletal characteristics in an orthodontic patient population.

Materials and methods: The records of the 1066 patients seeking orthodontic treatment were screened for maxillary lateral incisor agenesis (MLIA). The following data were recorded for each subject: age; gender; unilateral or bilateral agenesis of MLI and side. The lateral cephalogram of each subject with MLIA was digitally traced. The data were compared to age-matched control orthodontic patients with skeletal Class I.

Results: The prevalence of maxillary lateral incisor agenesis was 4.9% (52 patients) in which 63.5% were females. There was a significant difference between MLIA patients and controls in sagittal relationships (ANB, Wits, AB plane, angle of convexity and Co-A/Co-Gn differential analyses) p?Conclusions: Patients with maxillary lateral incisor agenesis showed a significant tendency for skeletal Class III compared with the Class I control. This could be attributed to maxillary hypoplasia/retrognathia.     

A Study of the Root Canal Morphology of Mandibular Anterior Teeth Using Cone-beam Computed Tomography in a Chinese Subpopulation

IntroductionThe purpose of this study was to investigate the root canal configuration of the mandibular anterior teeth using cone-beam computed tomographic (CBCT) imaging in a Chinese subpopulation.MethodsA total of 3,871 CBCT images of mandibular anterior teeth were collected from 648 patients who accepted CBCT projection as a preoperative assessment for implants or orthodontic treatment. The following items were recorded and evaluated: tooth position, root number, canal number, root canal type, the distance between the anatomic apex and the point at which the canal divided into 2 for mandibular anterior teeth with 2 root canals (excluding canines with 2 roots), and the distance between the 2 root canal orifices. The Fisher exact test was used to analyze the correlation between the number of root canals and tooth position.ResultsAll of the incisors in this study had 1 root, and 1.32% of the canines had 2 roots. The prevalence of 2 root canals in the lateral incisors (354, 27.36%) was higher than that in the central incisors (202, 15.71%) (P < .05) and the canines (81, 6.27%) (P < .05).ConclusionsThere is a high prevalence of 2 root canals in the mandibular anterior teeth of the studied Chinese subpopulation. This study provides detailed information about the root canal morphology of mandibular anterior teeth in a Chinese subpopulation.     

锥形束CT法在上颌前牙区牙龈厚度评估中的应用

目的 探究锥形束CT(CBCT)法在不同牙位、不同牙龈生物型及不同牙龈退缩类型上颌前牙区牙龈厚度评估中的应用。方法 选择2018年3月至2019年7月在我院口腔科接受CBCT检查的40例患者（225颗患牙）为研究对象，测量上颌前牙区龈缘下2 mm各患牙的牙龈厚度，比较其在不同牙位、牙龈生物型、牙龈退缩类型的差异。结果 中切牙的牙龈厚度（1.56±0.32） mm>侧切牙的牙龈厚度（1.34±0.28） mm>尖牙的牙龈厚度（1.13±0.24） mm；无退缩牙龈厚度（1.42±0.38） mm>退缩牙龈厚度（1.19±0.37） mm，退缩程度越深，牙龈厚度越小，差异具有统计学意义（P<0.05）；中切牙多为厚龈型，侧切牙和尖牙多为薄龈型；大部分患者为薄龈生物型，薄龈型相比厚龈型更容易发生牙龈退缩。CBCT法测量牙龈厚度具有准确性和可重复性。结论 CBCT法在上颌前牙区不同牙位、牙龈生物型及牙龈退缩类型上评估牙龈厚度具有良好的准确性。有助于牙科医生选择牙周治疗方案、评估美学修复预后提供参考依据。     

The prevalence of congenitally missing permanent teeth in Japanese children: A survey conducted in south-west area of Kanto district

AimThe purpose of this study was to investigate the prevalence of congenitally missing permanent teeth in Japanese children residing in south-west area of Kanto district in recent years.MethodsPanoramic radiographs taken for dental treatment between 1990 and 2007 were used to evaluate the congenitally missing permanent teeth excluding the third molar. The participants of this study consisted of 2,125 children aged between 7 and 20 years.ResultsThe congenitally missing teeth were observed in 251 participants (11.8%). The majority of the participants (114) presented with only one tooth missing, and there was a general tendency that the number of participants gradually decreased as the number of missing teeth increased. A total of 539 teeth were congenitally missing, and mandibular second premolar was the most frequently missing tooth (153 teeth), followed by mandibular lateral incisor (86 teeth), maxillary second premolar (71 teeth), maxillary lateral incisor (61 teeth). Only one missing tooth (114 participants) was found most frequently in mandibular lateral incisor (30 participants), followed by mandibular second premolar (28 participants). There was a tendency that congenitally missing teeth occurred symmetrically; especially most of the participants who had two missing teeth (80 in 88 participants) were symmetrically missing.ConclusionThe prevalence of congenitally missing permanent teeth in this study was 11.8% and it was comparable to those reported in previous studies of Japanese population evaluated using panoramic radiographs.     

新疆地区人群上颌第二磨牙牙根和根管形态的CBCT研究

目的 采用锥形束CT研究新疆地区人群上颌第二磨牙的牙根和根管形态，为本地区口腔临床诊疗提供参考依据。方法 对纳入研究的539例新疆地区人群的上颌第二磨牙，利用CBCT对其牙根形态、数目，根管形态、数目和弯曲度，牙冠颊舌径和近远中径以及对称性进行观察、分析和统计。结果 在1017颗上颌第二磨牙中，三根牙的检出率最高为85.2%，四根牙检出率最低为3.2%，不同牙位和性别在牙根形态上的分布存在统计学差异；MB2的检出率与年龄无统计学差异；56岁及以上年龄组的四根牙检出率最高。颊舌径、近远中径的平均测量值越大，其对应的根管数目越多。上颌第二磨牙的牙根数目和形态对称、根管形态及四种特征均对称方面较高，上颌第二磨牙近颊根管和远颊根管68%为重度弯曲，弯曲位于根中1/3较多。结论 新疆地区人群上颌第二磨牙以三根牙为主，对称率较高，弯曲程度大，但存在一些牙根和根管的变异，临床上可以运用CBCT来指导诊疗。     

Root resorptions related to ectopic and normal eruption of maxillary canine teeth – A 3D study

Abstract

Objective. To assess the incidence and severity of root resorption of maxillary incisors caused by ectopically and normally erupting maxillary canines and to analyse factors influencing root resorption of incisors using cone beam computed tomography. Subjects and methods. The study sample comprised 59 patients with a total of 80 canines. Forty-six of the canines, in 37 patients, were defined as ectopic and 34 canines, in 22 patients, were defined as normal. The severity of root resorptions were analysed according to studies by Ericson and Kurol. Multiple logistics regression was used to evaluate the association between various factors and root resorptions. Results. The prevalence of root resorptions was significantly higher in the ectopic canine group, 11.0% of the central incisors and 67.6% of the lateral incisors in comparison to 0% and 36.2% in the normal erupting group. Most resorptions were defined as ‘slight’ and were located in the middle third of the root. There was a statistically significant relationship between canines located mesial to the midline of the lateral incisor and root resorption on the maxillary incisors. Conclusion. The present results show that root resorption of maxillary lateral incisors was common in patients referred to CBCT imaging due to maxillary canine eruption disturbances. Although significantly more frequent in patients with ectopically erupting canines, lateral incisor resorption was also found in association with approximately every third of the normally erupting canines. The best predictor for root resorption seemed to be location of the canine mesial in relation to the midline of the lateral incisor root.     

Tomographic evaluation of buccal bone in different skeletal patterns and incisors inclination

Objective

The aim of this study was to correlate the absence of BB with skeletal patterns and incisor inclination using cone-beam computed tomography (CBCT).

Methods

The sample comprised CBCT images of 45 patients undergoing orthodontic treatment. BB was classified in each third of the anterior teeth as critical, slender, regular, and thick. The skeletal pattern was determined by the ANB (A point, nasion, B point) angle and the incisor inclination using the 1.NA and 1.NB measurements and the interincisal angle (1:1).

Results

In both analyses, the skeletal pattern of class II revealed better BB in the cervical and middle thirds than classes I and III. A higher proportion of critical BB was found in the middle thirds, and the apical third presented the best regular and thick BB conditions, mainly class I. Less BB was observed in middle and apical thirds in the upper incisors and in cervical thirds in lower incisors, mostly when they were more upright.

Conclusions

Knowledge of alveolar bone height and thickness can alter the treatment plan in orthodontics. During orthodontic treatment, more attention should be paid to the lower incisors and vertical teeth because of poor BB conditions, especially in class III skeletal patterns.

     

The quality of root canal treatment and periapical status of permanent teeth in Turkish children and teens: a retrospective CBCT study

Objective

This study aimed to assess the quality of root canal fillings and the prevalence of periapical radiolucencies in the permanent teeth of 6–18 year-old Turkish children.

Methods

CBCT images of 150 patients’ 235 teeth with a mean age of 16.0?±?2.06 years were included. Root development stage, quality of root canal filling, the presence and severity of periapical radiolucencies, and their relationship with anatomical structures were recorded. Correlations between the quality of root canal filling, periapical lesion, and lesion size were assessed using regression analyses.

Results

A total of 235 teeth (528 root canals) were evaluated. 65.5% of root canals had periapical lesions. Immature roots and mandibular teeth had the highest prevalence and the largest size of periapical radiolucencies (p?<?0.05). Overfilling (n?=?52), underfilling (n?=?93), unfilled (n?=?46), inhomogeneously filled (n?=?113) root canals and poor coronal restoration (n?=?85 teeth) were observed in terms of technical failures of endodontic treatment. The quality of endodontic treatment was associated with the presence of periapical lesion and lesion size (p?<?0.05). Teeth with under-filled, overfilled or inhomogeneously filled root canals and poor coronal restoration had a periapical lesion larger than 5 mm (p?<?0.05). Immature teeth were most associated with the presence of lesion (OR?=?4.07) and the lesion size?>?5 mm (OR?=?3.71).

Conclusion

The prevalence of periapical radiolucencies in young permanent teeth showed an increase when the tooth was an incisor, had incomplete root development, or the root filling had technical errors.

     

Evaluation of Root Canal Configuration of Maxillary Molars in a Brazilian Population Using Cone-beam Computed Tomographic Imaging: An In Vivo Study

Introduction

The aim of this study was to analyze and characterize root canal morphology of maxillary molars of the Brazilian population using cone-beam computed tomographic (CBCT) imaging.

Methods

Patients referred for a CBCT radiographic examination for accurate diagnosis and treatment planning were enrolled in the study. A total of 620 healthy, untreated, fully developed maxillary first and second molars were included (314 first molars and 306 second molars). The following observations were recorded: (1) number of roots and their morphology, (2) number of canals per root, (3) fused roots, and (4) primary variations in the morphology of the root canal systems.

Results

First and second molars showed a higher prevalence of 3 separate roots, mesiobuccal, distobuccal, and palatal, with 1 canal in each root (52.87% and 45.09%, respectively). Two canals in the mesiobuccal roots represented 42.63% of teeth, whereas mesiobuccal roots of second molars presented 2 canals in 34.32%. The most common anatomic variation in the maxillary first molar was related to the root canal configuration of the mesiobuccal root, whereas the root canal system of the maxillary second molar teeth showed more anatomic variables.

Conclusions

Mesiobuccal roots of maxillary molar teeth had more variation in their canal system than the distobuccal or palatal roots. The root canal configuration of the maxillary second molars was more variable than the first molars in a Brazilian population. CBCT imaging is a clinically useful tool for endodontic diagnosis and treatment planning.     

Supernumerary teeth amongst Iranian orthodontic patients. A retrospective radiographic and clinical survey

Abstract

Objective . To investigate the prevalence, characteristics (malocclusion, location, type) and gender distribution of supernumerary teeth (ST) in an Iranian orthodontic population. Material and methods . A retrospective study was carried out using radiographs (periapicals, panoramic) and study models of 1751 subjects (870 girls, 881 boys; age range 9–27 years). The Pearson chi-square test was used to determine differences in the distribution of ST when stratified by gender and malocclusion type. Results . Fourteen ST were found in 13 patients (six males, seven females), giving a prevalence rate of 0.74%. The prevalence rate of ST was higher in Class III malocclusions (5.2%) and was a rare finding among Class II malocclusions (0.1%). The occurrence rate of ST was higher in maxilla (78.5%) than in mandible (21.5%). The most common type of ST was the conical form (43%). We did not observe any late-developing paramolar or distomolar ST. Conclusion . The prevalence rate of ST in our study was 0.74% and ST were more common among Class III malocclusions.     

Alveolar bone response to maxillary incisor retraction using stable skeletal structures as a reference

ObjectivesTo evaluate alveolar bone change in relation to root position change after maxillary incisor retraction via cone-beam computed tomography (CBCT) using stable skeletal structures as a reference.Materials and MethodsA total of 17 subjects (age 24.7 ± 4.4 years) who required retraction of the maxillary incisors were included. Labial and palatal alveolar bone changes and root change were assessed from preretraction and 3 months postretraction CBCT images. The reference planes were based on stable skeletal structures. The Kruskal-Wallis test and Wilcoxon signed-rank test were used to compare changes within and between groups, as appropriate. Spearman rank correlations were used to identify the parameters that correlated with alveolar bone change. The significance level was set at .05.ResultsThe labial alveolar bone change after maxillary incisor retraction was statistically significant (P < .05), and the bone remodeling/tooth movement (B/T) ratio was 1:1. However, the palatal bone remained unchanged (P > .05). The change in inclination was significantly related to labial alveolar bone change.ConclusionsUsing stable skeletal structures as a reference, the change in labial alveolar bone followed tooth movement in an almost 1:1 B/T ratio. Palatal alveolar bone did not remodel following maxillary incisor retraction. The change in inclination was associated with alveolar bone change.     

运用CBCT分析角度螺丝通道在上颌切牙区早期及延期种植修复中应用的可行性

目的 通过锥形束CT(cone beam computer tomography,CBCT)数据研究角度螺丝通道（angulated screw channel,ASC）在上颌切牙早期及延期种植修复中应用的可行性。方法 选择114位符合纳入标准的受试者CBCT数据，共119个上颌切牙位点，在Simplant软件中参考对侧同名牙的形态对缺牙区进行虚拟修复体牙冠设计，并在此基础上进行种植体虚拟植入，测量以修复为导向与以牙槽骨骨量为导向虚拟植入种植体之间的夹角，以及以牙槽骨骨量为导向虚拟植入种植体时螺丝通道在理想修复体牙冠上的穿出位置，并记录实现螺丝通道从腭侧穿出时所需ASC的最小角度。结果 在119颗上颌切牙虚拟种植方案中，以修复为导向与以骨量为导向虚拟植入种植体之间存在夹角，且在不同性别、不同牙位之间存在统计学差异，女性的夹角大于男性，中位数分别为10.00°（5.30°～14.15°）和6.80°（3.80°～9.30°），侧切牙的夹角大于中切牙，中位数分别为14.45°（9.80°～19.43°）和6.50°（3.85°～9.75°）。以骨量为导向虚拟植入种植体螺丝通道在理想修复体牙...     

The Hybrid Hyrax Distalizer,a new all-in-one appliance for rapid palatal expansion,early class III treatment and upper molar distalization

Abstract

Growing class III patients with maxillary deficiency may be treated with a maxillary protraction facemask. Because the force generated by this appliance is applied to the teeth, the inevitable mesial migration of the dentition can result in anterior crowding, incisor proclination and a possible need for subsequent extraction therapy. The Hybrid Hyrax appliance, anchored on mini-implants in the anterior palate, can be used to overcome these side-effects during the facemask therapy. In some class III cases, there is also a need for subsequent distalization after the orthopaedic treatment. In this paper, clinical application of the Hybrid Hyrax Distalizer is described, facilitating both orthopaedic advancement of the maxilla and simultaneous orthodontic distalization of the maxillary molars.     

A comparison of the use of cone-beam computed tomography and panoramic radiography in the assessment of pre-eruptive intracoronal resorption

Objective: This study aimed to investigate the prevalence of pre-eruptive intracoronal resorption (PIR) using cone beam computed tomography (CBCT) and panoramic radiography and to compare the findings of these imaging techniques.

Methods: This retrospective study consisted of 733 patients who had at least one unerupted tooth and had undergoneimaging with both three-dimensional (3D) CBCT and two-dimensional (2D) panoramic radiography. In all the images, the number of teeth with intracoronal resorption, affected tooth type and number, and size and location of the PIR defects were recorded. The McNemar test was used to compare the prevalence of PIR in the CBCT and panoramic images.

Results: Fewer PIR defects were detected in the panoramic images (3.1% of the patients) than in the CBCT images (9.5% of the patients) (pConclusions: CBCT detected more cases of PIR than panoramic radiography. The mandibular third permanent molar was the most commonly affected tooth.