Effect of Field Of View on Detection of External Root Resorption in Cone-Beam Computed Tomography

Introducing a new auto edge detection technique capable of revealing cervical root resorption in CBCT scans with pronounced metallic artifacts

Cervical resorption is a serious threat to the longevity of the teeth. In this study, the Canny edge-detection algorithm was applied on CBCT images to compare the accuracy of original and Canny views for diagnosing cervical resorption in endodontically treated teeth. Intracanal metallic posts were inserted in 60 extracted teeth being randomly divided into three groups: control, 0.5 mm, and 1 mm cervical resorption. CBCT scans of the teeth were presented to three observers in both original and Canny formats with the accuracy being determined by receiver operating characteristic (ROC) analysis. The DeLong test was used for paired comparisons with the significance level set at 0.05. The highest accuracy belonged to Canny images in 1 mm resorption, followed by Canny images in 0.5 mm resorption, original images in 1 mm resorption, and original images in 0.5 mm resorption, respectively. The Canny images were significantly more accurate in the diagnosis of 0.5 mm (p < 0.001) and 1 mm (p = 0.009) resorption. Application of the Canny edge-detection algorithm could be suggested as a new technique for facilitating the diagnosis of cervical resorption in teeth that are negatively affected by metallic artifacts.

Successful Management of a Typical Class 3 Invasive Cervical Root Resorption with Modified Pulpotomy: A Case Report

Invasive cervical root resorption (ICRR) is a rare and clinically complex condition marked by the progressive loss of dental hard tissues below the junctional epithelium. This case report outlines the management of a 32-year-old female patient presenting with ICRR class 3 affecting a maxillary incisor. Despite the absence of symptoms, the expansive nature of the defect warranted conservative surgical intervention. The procedure involved the surgical removal of inflamed tissues, followed by an ultraconservative modified pulpotomy utilizing calcium-enriched mixture (CEM) cement through a surgical window. The selected intervention is substantiated by its potential benefits, such as minimal removal of tooth structure and the inherent biocompatibility and sealing capabilities of CEM cement. A one-year follow-up revealed arrested resorption, re-establishment of periodontal attachment, and successful esthetic restoration, affirming the efficacy of vital pulp therapy in surgically addressing advanced ICRR. Accurate diagnosis, strategic treatment planning, and a patient-centered approach proved critical in achieving favorable outcomes.

Invasive Cervical Root Resorption: A Comprehensive Review on Pathogenesis, Diagnosis, and Treatment

Invasive cervical root resorption (ICRR) is a dental pathology, marked by unexpected destruction originating in the cervical region of the tooth. This comprehensive literature review provides a holistic view into the pathogenesis, clinical manifestation, and precise management of ICRR, aiming to guide endodontists and enhance patient care and treatment outcomes. The review delves into the potential etiology of ICRR, covering contributing factors such as trauma, orthodontic treatment, and other pertinent conditions. It outlines the clinical and radiographic indicators, underscoring the crucial role of early detection and precise diagnosis in effectively managing and halting ICRR progression. The exploration of treatment approaches is thorough, ranging from non-surgical methods like vital pulp therapy or root canal treatment to surgical interventions. This review accentuates the essential role of interdisciplinary collaboration among diverse dental specialties in enhancing ICRR management. It highlights the importance of a consolidated strategy in enhancing treatment outcomes and preserving tooth structure and function. Moreover, it investigates prevention methods, risk evaluation, and identifies prospective research pathways to address the existing knowledge gaps.

Clinical Approach to External Cervical Resorption in the Anterior Teeth: A Case Report Study

External cervical resorption (ECR) is a pathology that is difficult to diagnose early, and because it is often confused with root decay, it can be treated inadequately and even result in tooth loss. Currently, treatment does not have a defined protocol, being widely varied in the literature. This article proposes that cases of ECR should be treated individually, following different criteria, based on aspects related to the patient and the tooth involved. Furthermore, this work illustrates, through a case report, how a patient can present unique characteristics that require treatment to be case-dependent and should be discussed among a multidisciplinary team.

How Does Voxel Size of Cone-beam Computed Tomography Effect Accurate Detection of Root Strip Perforations

Introduction

Our study aimed to assess the diagnostic accuracy of different voxel sizes for cone-beam computed tomography (CBCT) when detecting strip perforations of variable sizes. We used 0.2 and 0.3 mm3 voxel for detecting root strip perforations.

Methods and Materials

This was an in vitro study conducted on 155 extracted humans' mandibular first molars. The teeth were randomly divided into five groups (n=31). Perforation were not induced in the control group. In the remaining four groups, strip perforations of 0.5, 1, 1.5, and 2 mm diameters were created in the mesiolingual canal using #3 Gates Glidden drills. The CBCT scans were taken first with a 12×9 cm field of view (FOV), 90 kVp, 4 mA, and 0.2 mm3 voxel size for 24 sec and then with a 12×9 cm FOV, 90 kVp, 2 mA, and 0.3 mm3 voxel size for another 24 sec. Two observers evaluated the images and reported the largest diameter of perforations. The results were compared with the gold standard values (determined by an electronic digital caliper) using statistical methods, including the kappa coefficient and generalized estimating equation (P<0.05).

Results

Based on the findings of our study, the inter-observer agreement ranged from 58-100%, while the intra-observer agreement was reported to be around 100%. The difference in accuracy between 0.2 and 0.3 mm3 voxel sizes was not statistically significant (P>0.05). In addition, the accuracy of detecting different perforation sizes in the CBCT did not follow a specific pattern.

Conclusion

This in vitro study showed that CBCT is a reliable diagnostic tool, and even in lower dosages of 0.3 mm3 voxel size, image resolution and diagnostic accuracy was not affected. Moreover, smaller root perforations could be detected as accurately as larger ones with CBCT.

Diagnostic Accuracy of High Resolution Cone-beam Computed Tomography and Standard Mode Cone-beam Computed Tomography in Internal Root Resorption

Introduction

The purpose of this study was to compare the high resolution cone-beam computed tomography (CBCT) and standard mode CBCT diagnostic accuracy in internal root resorption with different sites and sizes.

Methods and Materials

Eighty single rooted human teeth with visible pulps in periapical radiography were split mesiodistally along the coronal plane. Internal resorption like lesions were created in three areas (cervical, middle and apical) in labial wall of the canals in different diameters. High resolution CBCT (CBCT-H) and standard mode CBCT (CBCT-C) were taken from each tooth. Two observers examined the high resolution CBCT and standard mode CBCT to evaluate the presence of resorption cavities. The data were statistically analyzed and degree of agreement was calculated using Cohen's kappa (k) values. Data were analyzed by SPSS 20 software and sensitivity, specificity and positive and negative predictive value for both methods were calculated. Data were analyzed using the Mac-Nemar and chi-square tests.

Result

The positive predictive value and negative predictive value in CBCT-H was higher than that of CBCT-C, all of which indicates that the CBCT-H diagnostic test is more sensitive and more accurate than CBCT-C. Kappa statistics showed that there is a strong and complete agreement between the CBCT high resolution and reality (kappa: 0.72) and in the Standard CBCT method, a moderate agreement has been obtained with reality (Kappa: 0.45).

Conclusion

According to our in vitro study CBCT high resolution has a higher diagnostic accuracy than conventional CBCT.

The effect of varying cone beam computed tomography image resolution and field-of-view centralization on effective radiation dose

OBJECTIVES

To investigate changes in the effective radiation dose (E) in relation to variations in voxel (VOX) size settings and the field-of-view (FOV) centralization. Methods: This cross-sectional dosimetry study used nanoDot OSLD dosimeters placed at 25 pre-determined sites in the head and neck slices of a RANDO male phantom to measure the absorbed radiation. The imaging scans took place at King Abdulaziz University Dental Hospital, Jeddah, Saudi Arabia between September 2016 and May 2017 using the i-CAT classic cone beam computed tomography (CBCT)  unit. Three VOX size setting were examined: 0.2 mm, 0.3 mm and 0.4 mm. The FOV was alternatively eccentrically centered on the maxillary and mandibular arches while holding all other factors constant. Effective radiation doses were calculated for each VOX size and FOV centralization setting. Results: An inverse and indirect relation was found between E and the VOX size setting with smaller VOX yielding higher E. CBCT scans centered on the mandible resulted in higher E than scans centered on the maxilla. Conclusion: Effective radiation doses are significantly affected by changes in VOX size settings and FOV centralization options. This reflects on the potential radiation risk to patients and highlights the importance of choosing exposure parameters carefully.

Incidence of Dentinal Crack Formation Using ProTaper Universal and WaveOne Systems in Straight and Curved Root Canals

Introduction

This study aimed to compare dentinal micro crack formation following root canal instrumentation with ProTaper Universal (PTU) and WaveOne (WO) rotary systems in straight and curved root canals.

Methods and Materials

One hundred mesiobuccal (MB) straight and curved canals of mandibular molars meeting inclusion criteria were divided into two control (n=10) and four experimental groups (n=20). After mounting the teeth and simulating the periodontal ligament, all the MB canals were coronally flared using Gates-Glidden drills #3 and 2 respectively. Then, in the experimental groups, the canals were instrumented with either PTU files (S_x, S₁, S₂, F₁, F₂), or Primary WO (25/0.08). Afterwards, roots were horizontally sectioned at 2, 4, and 6 mm from the apices, and evaluated under a microscope under 20× magnification. Data were analyzed with the Chi-Square and Kruskal-Wallis tests. The significance level was set at 0.05.

Results

The control groups showed no cracks. There was no significant difference between the two systems in the straight root canals (P>0.05). But in the curved root canals, PTU produced significantly more cracks (P<0.05) with the complete crack type which was dominant (P=0.013) compared to WO.

Conclusions

This in vitro study showed that in curved root canals, instrumentation with reciprocal WO system may be safer than full rotational PTU instruments regarding crack formation.