Effect of Object Position in Cone Beam Computed Tomography Field of View for Detection of Root Fractures in Teeth with Intra-Canal Posts

Influence of the technical parameters of CBCT image acquisition on vertical root fracture diagnosis: a systematic review and meta-analysis

OBJECTIVES

To evaluate the influence of image acquisition parameters (voxel, FOV, kVp, mA) on the accuracy of cone-beam computed tomography (CBCT) in detecting vertical root fracture (VRF).

MATERIAL AND METHODS

Searches were performed in 6 main databases and the gray literature, without restrictions of language or date. Observational clinical studies (OCS) and in vitro-extracted teeth (IV) studies were considered eligible for inclusion when investigating the accuracy (sensitivity, specificity) of CBCT in detecting VRF in human teeth. The risk of bias was assessed using QUADAS-2, and a meta-analysis was performed using Review Manager v5.4 software and Jamovi software v1.6.

RESULTS

A total of 60 out of 132 articles was included after fulfilling the eligibility criteria. Of these, 54 were IV studies while 6 were OCS. In the IV studies, it was seen that smaller FOV sizes tended to present higher accuracy values. The meta-analysis of the 6 OCS showed that the overall sensitivity and specificity values for 0.08 mm and 0.1 mm voxels were greater (0.84 and 0.79, respectively) than the sensitivity and specificity values for 0.125 mm and 0.2 mm voxels (0.70 and 0.55, respectively).

CONCLUSIONS

Despite the uncertain risk of bias found for the IV and OCS studies, smaller voxel and FOV sizes seem to provide more accurate VRF detection values when using CBCT.

CLINICAL RELEVANCE

This information is crucial for supporting the clinician when prescribing CBCT in cases of a clinical suspicion of VRF, and contributes to the personalization of the CBCT prescription, thereby ensuring greater accuracy in the VRF diagnosis. Registration This protocol was registered at the PROSPERO database (International Prospective Register of Systematic Review) under registration number CRD42020210118.

Minimal Detectable Width of Tooth Fractures Using Magnetic Resonance Imaging and Method to Measure

INTRODUCTION

Vertical root fracture (VRF) in root canal-treated (RCT) teeth is a common cause of pain, bone resorption, and tooth loss. VRF is also difficult to diagnose and measure. Magnetic resonance imaging (MRI) has the potential to identify VRF due to beneficial partial volume averaging, without using ionizing radiation. This investigation aimed to describe the narrowest VRFs detectable based on MRI, using micro-computed tomography (microCT) as the reference standard and proposes a method using profile integrals to measure the widths of small VRFs.

METHODS

VRFs were induced in 62 RCT tooth root samples. All samples were imaged in a phantom using MRI and reference imaging was obtained using microCT. The stacks of 3-dimensional axial MRIs were assessed by 3 board-certified endodontists. Evaluators determined the most coronal slice within the stack that was discernible as the extent of the VRF. This slice was measured on correlated microCT sections to determine the minimum VRF width (μm) detectable using a profile integral-based method to measure small fractures and negate the effects of the point spread function.

RESULTS

Using profile integrals to measure VRF width was repeatable and resulted in estimates that were on average 1 μm smaller than known reference widths. Adjusted median VRF width detected using MRI was 45 μm (first quartile: 26 μm, third quartile: 64 μm).

CONCLUSION

Using profile integrals is a valid way to estimate small VRF width. The MRI approach demonstrated ability to repeatedly detect VRFs as small as 26 μm.

Diagnosis of cracked teeth using cone-beam computed tomography: literature review and clinical experience

Cone-beam computed tomography (CBCT) has been widely used in diagnosis of vertical root fractures (VRFs) in recent years. According to the American Association of Endodontists (AAE) classification, there are five types of cracked teeth and VRF is one of them. Due to the variability and overlapping of the cracks and fractures, some narrow fractures on the roots of VRFs could not be detected by CBCT, and some wide cracks on the crown of cracked teeth could be detected by CBCT. In this review, we firstly discussed the value of CBCT in the diagnosis of the AAE five types of cracked teeth and presented CBCT manifestations of some typical cases. Secondly, we summarized the factors influencing the diagnosis of cracks/fractures using CBCT, namely, CBCT device-related factors, patient-related factors, and evaluator-related factors. The possible strategies to improve the diagnostic accuracy in the clinic practice are also discussed in this part. Finally, we compared the differences of root fractures with lateral canals and external root resorption on CBCT images.

Cone-beam computed tomography artifacts in the presence of dental implants and associated factors: an integrative review

Purpose

This study was conducted to review the literature regarding the types of cone-beam computed tomography (CBCT) artifacts around dental implants and the factors that influence their formation.

Materials and Methods

A search strategy was carried out in the PubMed, Embase, and Scopus databases to identify published between 2010 and 2020, and 9 studies were selected. The implants included 306 titanium, titanium-zirconium, and zirconia implants, as well as 5 titanium cylinders.

Results

The artifacts around the implants were the beam-hardening artifact, the streaking artifact, and band-like radiolucent areas. Some factors that influenced the formation of artifacts were the implant material, bone type, evaluated regions, distance, type of CBCT, field of view (FOV) size, milliamperage, peak kilovoltage (kVp), and voxel size. The beam-hardening artifact was the most widely reported, and it was minimized in protocols with a smaller FOV, larger voxels, and higher kVp.

Conclusion

The risk and benefit of these protocols in individuals with dental implants must be considered, and clinical examinations and complementary radiographs play an essential role in implantology.

Role of Computed Tomography Scan in Dental Trauma: A Cross-Sectional Study

Background:

Dental trauma is caused by fracture(s) in the vertical plane and the horizontal plane of roots. The objective of this study is to perform multiple diagnostic modalities for the diagnosis of horizontal root fracture(s) of the tooth.

Methods:

A total of 250 patients with dental complaints were subjected to intraoral radiography, multidetector helical computed tomography (MDHCT), and limited cone beam computed tomography (LCBCT). The suspected tooth was extracted, visually inspected, and subjected to microcomputed tomography (micro-CT). Images were observed in the lightbox, and a fracture was considered if it had been directly visualized as radiolucent line traversing tooth root. Wilcoxon test/Tukey post hoc test was performed at 99% of confidence level.

Results:

With respect to visual inspection, for LCBCT, intraoral radiography, MDHCT, and micro-CT, sensitivities were 0.988, 0.972, 0.967, and 0.979; accuracies were 0.956, 0.785, 0.905, and 0.888; false-positive values were 5, 21, 12, and 11; and false-negative values were 3, 24, 3, and 11, respectively. The area of the image visible at one time was in the order of treatment without radiography < intraoral radiography < MDHCT < micro-CT < LCBCT.

Conclusion:

The LCBCT had the highest sensitivity and accuracy for diagnosis of horizontal tooth root fracture(s).

Level of Evidence:

I.

Trial Registry:

researchregistry3647, dated December 31, 2016 (www.researchregistry.com).

Effect of anatomical region on the formation of metal artefacts produced by dental implants in cone beam computed tomographic images

OBJECTIVES

To quantitatively compare metal artefacts produced by implants in different maxillomandibular regions on cone beam CT (CBCT) images.

METHODS

A total of 200 implants selected from CBCT examinations were divided into four groups: Group 1 (n = 50)-implants located in the anterior maxilla; Group 2 (n = 50)-implants located in the posterior maxilla; Group 3 (n = 50)-implants located in the anterior mandible and Group 4 (n = 50)-implants located in the posterior mandible. The implants were further classified as isolated or adjacent to other implants. Three axial reconstructions were selected for each sampled implant (apical, middle and cervical). On each slice, the artefacts produced by the implants were counted. The Mann-Whitney test was used to compare the variables between groups. The Kruskal-Wallis and Student-Newman-Keuls tests were used to compare the axial reconstructions.

RESULTS

The mandible showed a greater number of artefacts than the maxilla (apical image: p = 0.0024; middle image: p < 0.0001). The anterior region produced more artefacts than the posterior region (apical image: p = 0.0105; middle image: p < 0.0316). There was no significant difference in the number of artefacts between isolated and adjacent implants, and the cervical image was most affected by artefacts.

CONCLUSIONS

Dental implants always produce metal artefacts in CBCT images, and these artefacts are affected by the anatomical location in the dental arch.

Vertical root fracture: Biological effects and accuracy of diagnostic imaging methods

This review assessed the most up-to-date literature on the accuracy of detecting vertical root fractures (VRFs] using the currently available diagnostic imaging methods. In addition, an overview of the biological and clinical aspects of VRFs will also be discussed. A systematic review of the literature was initiated in December of 2015 and then updated in May of 2016. The electronic databases searched included PubMed, Emabse, Ovid, and Google Scholar. An assessment of the methodological quality was performed using a modified version of the quality assessment of diagnostic accuracy studies tool. Twenty-two studies were included in this systematic review after applying specific inclusion and exclusion criteria. Of those, 12 favored using cone beam computed tomography (CBCT) for detecting VRF as compared to periapical radiographs, whereas 5 reported no differences between the two methods. The remaining 5 studies confirmed the advantages associated with using CBCT when diagnosing VRF and described the parameters and limitations associated with this method, but they were not comparative studies. In conclusion, overwhelming evidence suggests that the use of CBCT is a preferred method for detecting VRFs. Nevertheless, additional well controlled and high quality studies are needed to produce solid evidence and guidelines to support the routine use of CBCT in the diagnosis of VRFs as a standard of care.