Cone-beam Computed Tomography Evaluation Research Articles

C-Shaped Canal Prevalence and Morphology in Maxillary Molar Teeth: A Cone Beam Computed Tomography Evaluation

C-Shaped Canal Prevalence and Morphology in Maxillary Molar Teeth: A Cone Beam Computed Tomography Evaluation

Retrospective Radiographic Evaluation of Implant Complications: CBCT-Based Study

Aim: Dental implants are a popular treatment option for patients with one or more missing teeth. With the increase in dental implant treatments, the complications encountered have increased. Therefore, it is very important to plan the implant by evaluating the anatomy of the area where the implant will be placed in three dimensions with cone beam computed tomography (CBCT). The aim of this study is to evaluate the prevalence of implant complications seen in CBCT after implant applications. Material and Methods: CBCT images of 500 patients obtained for different dental reasons were examined; among these, 300 dental implant images were evaluated retrospectively in terms of complications. The number, location and type of identified complications (perforation in the maxillary sinus, mandibular canal, cortical bone, nasal cavity, and mental canal; contact with the adjacent tooth root) were recorded. The data obtained were analyzed statistically using chi-square tests. Results: At least one complication was detected in 65% of the 300 dental implants evaluated. A total of 272 complications (1.4 complications per implant) were observed in 195 dental implants with complications. The number of implants with complications per patient was found to be 3.9. The most observed complication was found to be vertical bone resorption around the implant (45%). Complications were most frequently detected in the maxillary posterior region (40%). Conclusion: Three-dimensional CBCT evaluation of the area where the implant will be applied before and after treatment is very important to prevent possible complications.

Cone Beam Computed Tomography Evaluation of The Effect of Single Tooth Loss On Maxillary Sinus Mucosa Thickness

Aim: The aim of this study was to determine whether the loss of a single tooth is a risk factor for maxillary sinus mucosal thickening. Materials and Methods: This retrospective, observational, radiographic study was performed on individuals using cone beam computer tomography who applied to Department of Oral and Maxillofacial Surgery for implantation between January 2012 and January 2019. The edentulous sides of the patients were determined as the study group and the symmetrically toothed sides of the patients were determined as the control group. Maxillary sinus mucosa thickness (MSMT) obtained at the sinus floor, medial sinus wall, and lateral sinus wall were compared between the two groups. Results: Of the 105 patients included in the study, 51 were male and 54 were female. The ages of the patients ranged between 15 and 65 years, with a mean age of 32.92 ± 9.73 years. The MSMT of the lateral sinus wall on the toothed side were significantly higher in male patients than in female patients (p = 0.001 vs. p < 0.01, respectively). On the edentulous side, the MSMT of lateral sinus wall of men was significantly lower than that of women (p = 0.001 vs. p < 0.01). Conclusion: Implant and bone augmentation planning at the sinus floor on the edentulous side should be considered in terms of maxillary sinus complications and implant failure. In conclusion, the absence of a single tooth as a local odontogenic factor is not a risk factor for maxillary sinus mucosal thickening.

A Comparative Study of Deep Learning and Manual Methods for Identifying Anatomical Landmarks through Cephalometry and Cone-Beam Computed Tomography: A Systematic Review and Meta-Analysis

Background: Researchers have noted that the advent of artificial intelligence (AI) heralds a promising era, with potential to significantly enhance diagnostic and predictive abilities in clinical settings. The aim of this meta-analysis is to evaluate the discrepancies in identifying anatomical landmarks between AI and manual approaches. Methods: A comprehensive search strategy was employed, incorporating controlled vocabulary (MeSH) and free-text terms. This search was conducted by two reviewers to identify published systematic reviews. Three major electronic databases, namely, Medline via PubMed, the Cochrane database, and Embase, were searched up to May 2024. Results: Initially, 369 articles were identified. After conducting a comprehensive search and applying strict inclusion criteria, a total of ten studies were deemed eligible for inclusion in the meta-analysis. The results showed that the average difference in detecting anatomical landmarks between artificial intelligence and manual approaches was 0.35, with a 95% confidence interval (CI) ranging from −0.09 to 0.78. Additionally, the overall effect between the two groups was found to be insignificant. Upon further analysis of the subgroup of cephalometric radiographs, it was determined that there were no significant differences between the two groups in terms of detecting anatomical landmarks. Similarly, the subgroup of cone-beam computed tomography (CBCT) revealed no significant differences between the groups. Conclusions: In summary, the study concluded that the use of artificial intelligence is just as effective as the manual approach when it comes to detecting anatomical landmarks, both in general and in specific contexts such as cephalometric radiographs and CBCT evaluations.

Cone beam computed tomography evaluation of condyle position and joint space in a group of intra-articular disorders patients undergoing stabilization splint treatment

This cross-sectional study assesses condyle position and joint space using Cone Beam Computed Tomography (CBCT) in patients with intra-articular disorders undergoing stabilization splint treatment. Patients are categorized into three groups based on MRI findings: no disc displacement (no DD), disc displacement with reduction (DDwR), and disc displacement without reduction (DDwoR). The study involves 35 patients, each with at least one DDwR joint. CBCT evaluates joint space and condyle position, revealing wider anterior, posterior, and superior joint spaces in both DDwR (anterior: 2.48 ± 0.98mm; posterior: 1.83 ± 0.71mm; superior: 2.46 ± 0.81mm) and DDwoR groups (anterior: 2.41 ± 1.13mm; posterior: 2.65 ± 1.14mm; superior: 2.74 ± 0.88mm) compared to the no DD group. Posterior condyle position accounts for the highest prevalence, at 60.4%, in DDwR joints. While no significant difference is noted in condyle position and anterior and superior joint space among three groups, a significant difference is observed in posterior joint space between groups (p < 0.05). The study suggests that joint space may be greater in joints with disc displacement, and posterior condyle position likely predominates in joints with and without disc displacement. However, further research is needed due to the small sample size.

Accuracy evaluation of dental CBCT and scanned model registration method based on pulp horn mapping surface: an in vitro proof-of-concept

Background and aim3D fusion model of cone-beam computed tomography (CBCT) and oral scanned data can be used for the accurate design of root canal access and guide plates in root canal therapy (RCT). However, the pose accuracy of the dental pulp and crown in data registration has not been investigated, which affects the precise implementation of clinical planning goals. We aimed to establish a novel registration method based on pulp horn mapping surface (PHMSR), to evaluate the accuracy of PHMSR versus traditional methods for crown-pulp registration of CBCT and oral scan data.Materials and methodsThis vitro study collected 8 groups of oral scanned and CBCT data in which the left mandibular teeth were not missing, No. 35 and No. 36 teeth were selected as the target teeth. The CBCT and scanned model were processed to generate equivalent point clouds. For the PHMSR method, the similarity between the feature directions of the pulp horn and the surface normal vectors of the crown were used to determine the mapping points in the CBCT point cloud that have a great influence on the pulp pose. The small surface with adjustable parameters is reconstructed near the mapping point of the crown, and the new matching point pairs between the point and the mapping surface are searched. The sparse iterative closest point (ICP) algorithm is used to solve the new matching point pairs. Then, in the C + + programming environment with a point cloud library (PCL), the PHMSR, the traditional sparse ICP, ICP, and coherent point drift (CPD) algorithms are used to register the point clouds under two different initial deviations. The root square mean error (RSME) of the crown, crown-pulp orientation deviation (CPOD), and position deviation (CPPD) were calculated to evaluate the registration accuracy. The significance between the groups was tested by a two-tailed paired t-test (p < 0.05).ResultsThe crown RSME values of the sparse ICP method (0.257), the ICP method (0.217), and the CPD method (0.209) were not significantly different from the PHMSR method (0.250). The CPOD and CPPD values of the sparse ICP method (4.089 and 0.133), the ICP method (1.787 and 0.700), and the CPD method (1.665 and 0.718) than for the PHMSR method, which suggests that the accuracy of crown-pulp registration is higher with the PHMSR method.ConclusionCompared with the traditional method, the PHMSR method has a smaller crown-pulp registration accuracy and a clinically acceptable deviation range, these results support the use of PHMSR method instead of the traditional method for clinical planning of root canal therapy.

Cone-Beam Computed Tomography Evaluation of Maxillary Sinus Changes in Orthodontic Patients Treated With Extraction of Four First Premolars.

The objective of this study was to assess alterations in maxillary sinus mucosa thickness and the distances between the apexes of specific teeth and the maxillary sinus base in adult patients undergoing orthodontic treatment with the extraction of four first premolars. Twenty-one adults, averaging 24.85 years of age, received orthodontic therapy involving the extraction of all four first premolars. Cone-beam computed tomography scans were conducted before and after treatment to evaluate changes. Notably, post-treatment scans revealed a significant increase (P= 0.044) in the distance between the apex of the second premolar and the maxillary sinus floor, with an average augmentation of 1.0141 millimeters. However, no notable alterations were detected in the distances between the apexes of other teeth and the maxillary sinus or in maxillary sinus mucosa thickness. These findings suggest that orthodontic treatment with the extraction of four first premolars may elevate the distance between the maxillary sinus floor and the second premolar apex, which provides a reference for risk assessment and surgical design of first premolar extraction during orthodontic treatment.

FREQUENCY FOR THE USE OF CBCT ANALYSIS IN DENTISTRY

Cone beam computed tomography (CBCT) is a method that allows a three-dimensional evaluation of hard craniofacial structures with a lower radiation dose than classic CT. This method began to be used more and more frequently in dentistry. Background: The aim of the study was to evaluate the frequency for use of CBCT in dentistry. Methods: The study was addressed to dentists of various specialties from Oltenia region that completed an online questionnaire with 10 questions. Data were collected regarding the physician's specialty, the type of interventions for which the dentist recommends CBCT, how necessary this investigation is considered, and how invasive it is considered to be. The questionnaire was launched online for a period of 4 weeks, and dentists from the Oltenia region were invited to participate. The statistical analysis was carried out with the help of the Google Docs program, the section dedicated to forms, "Google Forms". Results: Young doctors chose this technology more frequently than doctors with more than 5 years of experience. Although implant planning is the primary reason for CBCT imaging in dentistry, CBCT is increasingly being used for other diagnostic purposes, such as periodontics and endodontics. In nearly 20% of cases, the primary diagnosis and/or treatment plan was changed following CBCT evaluation. Conclusions: There is an increasing trend in the use of CBCT in dentistry, especially by young graduates.

Cone-beam computed tomography evaluation of bone height and width in 7 different tooth regions of totally edentulous maxilla

Cone-beam computed tomography evaluation of bone height and width in 7 different tooth regions of totally edentulous maxilla

Cone-beam computed tomography evaluation of shaping ability of kedo-S square and fanta AF™ baby rotary files compared to manual K-files in root canal preparation of primary anterior teeth

BackgroundPediatric rotary file systems were developed to solve manual file limitations. With many systems available, it may be tricky to select the most appropriate one.Aimto assess & compare Kedo-S Square, Fanta-AF™-Baby rotary files with manual K-file concerning removed dentin amount, canal transportation, centric ability & root canal taper using CBCT in primary anterior teeth.DesignExtracted Seventy-five upper primary anterior teeth with intact 2/3 root length were collected and divided into three groups based on root canal instrumentation, group-I: prepared using K-file, group-II: prepared using Kedo-S Square, and group-III: prepared using Fanta AF™ Baby file. The teeth were imaged with CBCT before & following canal instrumentation. Then, the removed dentin amount was calculated at each root-canal level. The Kruskal-Wallis test was utilized to statistically analyze study data.ResultThe difference among the three groups was highly statistically significant at cervical & apical thirds concerning dentin thickness changes on both mesial & distal sides following canal preparation with the least removed dentin in the Kedo-S Square group(P < 0.0001). Regarding transportation & centering ability, a non-significant difference between the three groups was found. 80% of the Fanta AF™ Baby group had good-tapered preparation compared to the Kedo-S Square (72%) and K-file (40%) groups(P < 0.05).ConclusionKedo-S Square was preferable to Fanta-AFTM-Baby & manual K-files in primary root canal preparation.

Pre-eruptive intramural resorption in unerupted teeth: a cone-beam computed tomography evaluation of prevalence and related factors

ObjectivePre-eruptive intramural resorption (PEIR) is defined as an abnormal, well-circumscribed radiolucency within the coronal dentin of the tooth, which is often overlooked in plain radiographs. This study aimed to investigate the prevalence of PEIR and its related factors using cone-beam computed tomography (CBCT).MethodsCBCT images of 590 unerupted teeth were evaluated for the presence of PEIR, location of PEIR, number of lesions in the affected tooth, PEIR score, tooth angulation, tooth position, and pericoronal space. Binary logistic tests were used to analyze the association between the characteristics of PEIR and the patient’s demographic data and related factors.ResultsThe tooth prevalence of PEIR was 13.6% among unerupted teeth. However, it was noteworthy that 19.2% of the unerupted teeth with PEIR were planned to be kept. PEIR was significantly associated with transverse (p = 0.020), inverted-angulated (p = 0.035), and centrally-positioned teeth (p = 0.043). The severity of PEIR was more pronounced in teeth with distal (p = 0.019), lingual (p = 0.023), or inverted-angulated (p = 0.040) positions, and in the absence of pericoronal space (p = 0.036).ConclusionPEIR should be suspected in transverse, inverted-angulated, centrally positioned unerupted teeth, particularly in molars, with no pericoronal space. Further monitoring through CBCT is recommended in such cases.Clinical relevanceThe management of unerupted teeth does not always involve surgical removal. Instead, they could be utilized for artificial eruption or tooth transplantation. The present study emphasizes the significance of early detection of PEIR. Clinical recommendations for screening PEIR in unerupted teeth are also proposed, which can be applied to routine plain radiographs.

CBCT Evaluation of Root Canal Morphology of Maxillary First Premolar in Saudi Subpopulation

ABSTRACT Background and Objective: Clinicians must possess a comprehensive understanding of variations in canal morphology and configuration during endodontic procedures to enhance treatment success. This study aims to assess and analyze the canal configurations of maxillary first premolars using Cone-Beam Computed Tomography within the sub-population of Western Saudi Arabia. Materials and Methods: In this cross-sectional study, following the acquisition of ethical clearance from Batterjee Medical College in Jeddah, Saudi Arabia, a retrospective examination of Cone-Beam Computed Tomography (CBCT) scans of maxillary first premolars in adult patients was conducted. The study focused on quantifying the number of canals and characterizing their configurations, with classification based on Vertucci’s categorization. Results: The study examined 399 CBCT images of maxillary first premolars, revealing that type IV canal configurations were the predominant morphology (56.9%), followed by type V (24.6%). Significant gender-related disparities were observed, with females displaying a higher incidence of types I and V canals. At the same time, males exhibited a greater prevalence of types IV and VI canals. Notably, no substantial associations were discerned between canal types and age groups. Conclusion: Within the context of maxillary first premolars, type IV canal configuration emerged as the most prevalent. Gender-based distinctions were evident, with females predominantly presenting types I and V canal configurations, whereas males displayed a higher occurrence of types IV and VI canal configurations.

Research on the model of mandibular alveolar bone defect in rabbits

Objectives: The purpose of this study was to create an animal model of a mandibular alveolar bone defect without compromising the animal’s well-being. Materials and methods: A total of 24 New Zealand white rabbits underwent surgery to create mandibular alveolar bone defects. The animals were sacrificed at 2, 4, 6, 8, 10, and 12 weeks post-surgery. To assess bone regeneration at the surgical site, radiography, dental cone-beam computed tomography (CT), and histological examination using Hematoxylin and Eosin staining were performed on the skull. Results: A straightforward and easily executable method was devised to create the rabbit mandibular alveolar defect model. After 10 weeks, complete soft tissue and bone regeneration were observed. X-ray and cone-beam CT evaluations demonstrated a progressive increase in bone density from weeks 2 to 12. Histological examination revealed that the alveolar bone structure was formed incrementally at the surgical site. The bone and connective tissue had filled the defect after 8 weeks. Conclusion: The creation of a model of mandibular alveolar bone defects in rabbits is a straightforward process that can be used to assess the regeneration of alveolar bone at the defect site. This animal model can serve as the foundation for tests to evaluate the capacity of biomaterials to regenerate the alveolar bone Key words: mandibular alveolar bone, Alveolar bone defects, animal models, bone regenerative medicine, tissue engineering.

Cone Beam Computed Tomography Evaluation of Median Mandibular Lingual Canal in a Western Indian Subpopulation: A Cross-sectional Study

Introduction: The Mandibular Lingual Canals (MLC), which carry the sublingual artery, are present in the mandible near the genial tubercle. Identification of these canals is important before any dental surgical procedures. Aim: To identify and evaluate the mandibular lingual canal in Cone Beam Computed Tomography (CBCT) of the Western Indian Population. Materials and Methods: The current cross-sectional study was conducted at the Department of Oral Medicine and Radiology, Sumandeep Vidyapeeth, Vadodara, Gujarat, India between October 2022 and June 2023. A total of 100 CBCT volumes showing the mandibular anterior region were evaluated for the presence or absence of a mandibular lingual canal. The canals were further evaluated for their number, diameter, length, thickness of the buccal cortical plate, and the remaining bone above and below the canal. The evaluation was done by two separate investigators. The data were entered into Microsoft Excel and subjected to statistical analysis. Data collected were tested statistically using the Chi-square test. Results: A total of 59 males and 41 females’ mandibular CBCT volumes were evaluated, out of which 93 CBCT volumes showed the mandibular lingual canal. The maximum number (n=57) of individuals showed three canals, followed by two canals (n=26) and one canal (n=10). There was no statistical significance between genders regarding canal number, diameter, length, thickness of the buccal cortical plate, and the remaining bone above and below the canal. Conclusion: Three-canal morphology was the most common anatomical form of MLC found in the Western Indian population.

Evaluation of Palatal Thickness for the Placement of MARPE Device among a Cohort of Iraqi-Kurdish Population: A Retrospective CBCT Study.

This study aimed to evaluate and compare palatal thickness in adults for the placement of mini-implants for miniscrew-assisted rapid palatal expansion (MARPE) appliances using cone-beam computed tomography (CBCT) in a sample of Iraqi-Kurdish people. CBCT scans from 68 Kurdish patients, aged between 18 and 30 years, were assessed retrospectively. Of these, 37 were males and 31 were females. The measurements were performed at 3 mm from the mid-palatal suture. T-zone was selected for the anterior points, at the level of the palatal cusps of 2nd premolars, and the posterior point at the level of mesio-palatal cusps of 1st molars bilaterally. Palatal thickness of males and females bilaterally, as well as anterior and posterior areas, were measured and compared. An independent t-test was applied for comparison for normally distributed data, and the Mann-Whitney test was utilized for nonnormally distributed data. Additionally, Bonferroni correction was implemented for p-value adjustment. The mean palatal thickness at the anterior area was 6.06 mm for males, 6.17 mm for females on the right side, 5.94 mm for males, and 5.99 mm for females on the left side. The mean palatal thickness at the posterior area was almost the same for both genders (4.40 mm for males and 4.44 mm for females) on the right side, 4.35 mm for males, and 4.54 mm for females on the left side. Statistically, no significant difference was recorded between males and females, as well as right and left sides in both anterior and posterior regions; however, a very highly statistically significant difference (p < 0.001) was recorded when comparing total thickness, including both hard and soft tissue, between anterior and posterior regions. CBCT proves a highly effective modality in assessing palatal thickness and suggesting ideal locations for orthodontic mini-screw placement. Our examination of palatal thickness in a sample of Iraqi-Kurdish individuals revealed no statistical difference between genders or sides, but significant variations were noted between anterior and posterior thicknesses. Comprehensive clinical and pre-expansion CBCT evaluations are crucial for precisely determining the optimal placement of MARPE devices in each patient, ensuring successful outcomes.

Cone-beam computed tomographic evaluation and fracture resistance of endodontically retreated teeth using hyflex remover, Mtwo, and ProTaper retreatment file systems: An in vitro study

Introduction: One of the important factors contributing to the success of nonsurgical endodontic retreatment is the efficient removal of the obturating material from the root canal space. However, the fracture resistance of the tooth is likely to be affected by this procedure. Therefore, the study envisages assessing residual filling material in the root canals and the tooth’s resistance to fracture postretreatment using different retreatment files. Materials and Methods: Ninety extracted mandibular premolars with one root and a single canal were decoronated, followed by chemo-mechanical preparation, and thereafter, using the lateral compaction method, root canals were obturated. The samples were divided into three groups (n = 30) in accordance with retreatment file systems, namely Hyflex Remover, Mtwo, and ProTaper. All three groups were subjected to the cone-beam computed tomography evaluation to assess remnants of obturating material inside the canals postretreatment, and the same samples were further assessed for fracture resistance, respectively. The collected data were evaluated using the statistical analysis using the Kruskal–Wallis and post hoc Bonferroni tests. Results: There were significant differences in the volume of residual filling among the tested groups in the cervical thirds (P &lt; 0.05). The HyFlex remover file showed the highest fracture resistance (427.30 ± 33.53 N), followed by the Mtwo R (396.90 ± 27.17 N) and ProTaper R (378.50 ± 36.82 N). Conclusion: All the tested nickel-titanium retreatment files performed satisfactorily. Hyflex remover left the least amount of filling material in the cervical third and displayed the highest fracture resistance among the respective groups.

The use of guided tissue regeneration in endodontic Microsurgery: Setting a threshold

AimWe aimed to compare the radiographic outcomes of conventional and regenerative approaches in endodontic microsurgery (EMS) and set a critical defect size for healing in conventional and regenerative therapies. MethodologyThe study evaluated 53 root canal-treated teeth (33 patients) with periapical lesions. Among them, 19 teeth (35.8 %) were treated with regenerative treatment, whereas 34 teeth (64.1 %) were managed with the conventional approach. Conventional and regenerative approaches were performed by endodontic and periodontic residents under consultants’ supervision. Healing was evaluated after a minimum period of 6 months by comparing pre- and post-operative cone-beam computed tomography (CBCT) findings. The radiographic interpretation was conducted by a single examiner who was not participating in the surgeries and was blind on the type of treatment prior to CBCT evaluation. New healing criteria were proposed owing to the limitations on the present criteria in evaluating endodontic surgery after regenerative treatment. Critical measurements were calculated for each approach based on periapical lesion dimensions. ResultsThe regenerative approach presented significantly better healing than conventional treatment (mean, 1.21 and 1.59, respectively; p = 0.047). Based on the critical-point calculations, the conventional approach was effective in lesions of up to 3 mm depth and height, whereas the regenerative approach resulted in better healing rates in lesions with 3–9 mm depth and 3–6 mm height. ConclusionsPerforming the regenerative approach in EMS resulted in better healing rates than those of the conventional approach. The conventional approach is recommended for small periapical lesions, whereas the first had better results in larger lesions.

Cone beam computed tomography evaluation of c-shaped canal morphology in mandibular premolar teeth.

The aim of this study was to evaluate the prevalence and the morphology of c-shaped root canal(s) in mandibular premolars using cone beam computed tomography (CBCT) images. CBCT images of 1095 mandibular premolars were examined at coronal, middle, and apical levels of the root canals. The type, the level, and the position (buccal or lingual) of the c-shaped anatomy were recorded. Absolute counts and percentages of different groups and subgroups of C-shape morphologies were calculated. The Chi-square test was used to compare the prevalence of C-shaped morphology between mandibular first and second premolars. The Z-test for proportions in independent groups was used to analyze the differences in mandibular C-shaped premolar proportions between location (left and right side) and tooth (first or second premolars) (p=0.05). C-shaped root canal morphology was present in 44 teeth. The percentage of c-shaped morphologies was 6.9% and 1.6% in mandibular first and second premolars, respectively. Comparison of the first and the second premolars showed that C1 type (p=0.008) and C4b type (p=0.013) configurations are more common in the first premolars at the coronal level. In contrast, the C2 type configuration showed significantly higher prevalence in the second premolars (p=0.009). Additionally, the C4c type configuration was significantly frequent on the right premolars at the coronal level (p=0.038). C-shape canal morphology is a rare but complex anatomic feature in mandibular premolars. Therefore, clinicians should be aware of this complex root canal anatomy for the success of endodontic treatment in mandibular premolar teeth.

A Cone-beam Computed Tomography Evaluation of External Invasive Resorption of Unerupted Teeth. Report of Three Cases

Tooth resorption can occur either physiologically or pathologically and can be classified as internal or external. The term “external invasive resorption” (EIR) has been used to describe lesions originating from any surface defect exposing dentin. The absence of bacterial contamination, an intact pulp space, and a lesion consisting mainly of fibrovascular tissue characterize EIR. This study presents three cases of invasive resorption in unerupted teeth, emphasizing the importance of cone-beam computed tomography (CBCT). In two cases, the primary defect localized on the enamel surface, while in the third case, the focal point of the defect was not clear. CBCT provided detailed visualization of the resorption lesion's size and its relationship with surrounding structures, enhancing the diagnosis of EIR. Histological analysis of the third case confirmed the initial diagnosis. Invasive resorption can occur due to any surface defect in the case of unerupted teeth. Further research and correlation between radiographic and histological analysis are essential for the detection and classification systems in unerupted teeth.

Application of Hyperpure Chlorine Dioxide for Regenerative Endodontic Treatment of a Root-Canal-Treated Immature Tooth with External Cervical Resorption and Periapical Lesion: A Case Report

The consequences of traumatic injuries are pulp necrosis, periapical inflammation, and possible external cervical resorption (ECR). The concomitant cessation of root maturation and dentinogenesis in premature teeth result in a fragile tooth. Revascularization of the pulp might be an alternative treatment option. A 12-year-old patient was referred for retreatment of chronic apical periodontitis with acute exacerbation after root canal treatment of an upper central incisor. During gutta-percha removal, an ECR was detected. First, it was closed internally with Biodentine, followed by an external composite closure after a cone beam computed tomography evaluation. In the first session, chemomechanical cleaning was aided with sodium hypochlorite and hyperpure chlorine dioxide, and the canal was dressed with Ca(OH)2 until the next session. In the next session, only the low-toxicity, but adequate, bactericide hyperpure chlorine dioxide was applied for irrigation, before the provocation of periapical bleeding into the canal. The blood clots were covered with Biodentine, and the tooth was restored with composite filling. During the 24-month follow-up, clinical signs/symptoms had disappeared, and the periapical lesion was resolved. Increased root thickness in the apical third and decreased size of the apical foramen were detected. In conclusion, regenerative endodontic procedures could potentially be used to retreat immature teeth with persistent apical periodontitis and external cervical resorption.