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Objectives: To systematically evaluate the mean gray values (MGV) and noise provided by bone and soft tissue equivalent materials and air imaged with varied acquisition parameters in nine cone-beam computed tomography (CBCT) machines., Methods: The DIN6868-161 phantom, composed of bone and soft tissue equivalent material and air gap, was scanned in nine CBCT machines. Tube current (mA) and tube voltage (kV), field of view (FOV) size, and rotation angle were varied over the possible range. The effect of the acquisition parameters on the MGV and contrast-to-noise indicator (CNI) was analyzed by Kruskal Wallis and Dunn-Bonferroni tests for each machine independently (α = 0.05)., Results: Tube current did not influence MGV in most machines. Viso G7 and Veraview X800 presented a decrease in the MGV for increasing kV. For ProMax 3D MAX and X1, the kV did not affect the MGV. For the majority of machines, MGV decreased with increasing FOV height. In general, the rotation angle did not affect the MGV. In addition, CNI was lower with lower radiation and large FOV and did not change from 80 kV in all machines., Conclusions: The MGV and noise provided by the tested phantom vary largely among machines. The MGV is mainly influenced by the FOV size, especially for bone equivalent radiodensity. For most machines, when the acquisition parameters affect the MGV, the MGV decrease with the increase in the acquisition parameters., Advances in Knowledge: Knowing the expected GV behavior in different exposure conditions hold potential for future calibration of MGV among CBCT machines., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology and the International Association of Dentomaxillofacial Radiology.)

Objective: The objective of this study is to investigate the influence of metal artifact reduction (MAR) on two cone beam computed tomography (CBCT) units in the evaluation of bone graft loss adjacent to titanium (Ti) and zirconium (Zr) implants., Material and Methods: Twelve Ti and twelve Zr implants were placed in the posterior region of dry human mandibles. Bone graft was applied to the level of the cover screw. Bone graft loss was simulated in half of the sample (6 Ti and 6 Zr) by removing the graft material up to the third implant thread on the buccal surface. CBCT images were acquired on two units, varying the application of MAR (OP300-off and on; Eagle 3D-standard, intermediate, and extreme). The images were assessed by five evaluators that scored the presence of graft loss according to a 5-point scale. The diagnostic values were calculated and compared by non-parametric tests with a significance level of 5%., Results: Higher diagnostic values were achieved with MAR activated in the OP300 unit, for Ti and Zr (p < 0.05). On the Eagle 3D unit, MAR in extreme mode resulted in lower diagnostic values for both types of implants (p < 0.05). The diagnostic values of Ti implants were higher than Zr implants (p < 0.05)., Conclusion: The application of MAR influences the diagnosis of bone graft loss adjacent to Ti and Zr dental implants. However, the extreme mode of MAR in the Eagle 3D unit can impair the diagnostic task in both types of implants and should be avoided., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: To investigate the influence of combining levels of metal artifact reduction (MAR) tool with different filters and slice-thickness in the detection of mandibular canals perforated by implants on CBCT scans and to objectively assess the impact of the aforementioned combinations., Materials and Methods: Implants were placed above (8 implants) and inside (10 implants) mandibular canals of dried-mandibles. CBCT scans were obtained with the Eagle 3D unit (85 kVp, 8 mA, 5 × 5 cm FOV, 130 μm voxel size, and off/medium/high MAR levels). Examiners evaluated the scans under each MAR level and across different conditions: no filter, Sharpen 1×, Sharpen 2×; 0 mm, 1 mm, and 2 mm slice-thickness. The gray values on axial reconstructions were assessed. Area under the receiver operating characteristic curve (AUC), sensitivity, specificity, mean and standard deviation (SD) for gray values were calculated and compared by multi-way Analysis of Variance., Results: Overall, the AUC and sensitivity decreased with high-level MAR (p < 0.0001), regardless other variables tested. Enabling MAR tool decreased mean gray values (p < 0.01) and increasing MAR levels reduced the SD values on scans with Sharpen 2× (p < 0.012)., Conclusions: High-level MAR impairs the visualization of mandibular canals perforated by implants. Moreover, enabling MAR tool decreases the mean gray values., Clinical Relevance: MAR tool, filters, and slice thickness influence the image quality of CBCT scans. Therefore, it is important to evaluate the impact of these parameters on the diagnosis of mandibular canals perforated by implants., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: To investigate artefacts produced by different orthodontic brackets and wires in cone-beam computed tomography (CBCT) scans., Materials and Methods: Two dental arches were made using extracted human teeth and plaster. Three pairs of acetate plates containing different brackets - metallic, ceramic, and self-ligating ceramic with NiTi clip - along with a control plate (i.e., without brackets) were prepared. Wire changes (NiTi and steel) were made during CBCT acquisitions, performed with a fixed exposure protocol. Axial slices were selected for mean gray values and standard deviation measurement in three regions of interest (buccal, lingual, and tooth). Noise and contrast-to-noise ratio (CNR) were calculated and compared among the different brackets and wires by ANOVA with a significance level of 5%., Results: Overall, the buccal and tooth region were mostly affected by the metallic and self-ligating brackets, showing higher noise, and lower CNR (p < 0.05). On the other hand, less impact of ceramic brackets in the image quality was observed (p ≥ 0.05). The lingual region did not show expressive differences among the brackets and wire combinations (p ≥ 0.05). The presence of wire associated with the brackets did not worsen image quality (p ≥ 0.05)., Conclusions: In conclusion, metallic and self-ligating brackets have greater artefact expression than ceramic brackets. The wire did not influence image quality., Clinical Relevance: One should pay attention to the type of brackets when requesting a CBCT scan during treatment, as metallic and self-ligating brackets may express greater artefacts than ceramic brackets., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: The aim of this study was to present the development of a database (dataset) of panoramic radiographs., Study Design: Three radiologists labeled an image set consisting of 936 panoramic radiographs. Labeling includes tooth numbering (including teeth present and missing) and annotation of dental conditions (e.g., caries, dental restoration, residual root, endodontic treatment, implant, fixed prosthesis, incisal wear). The annotation process was performed in a Picture Archive and Communication System software customized for the study purposes using a small bounding box to delimit the entire tooth and items for radiographic diagnosis and a large bounding box to simultaneously delimit the 2 dental arches (maxilla and mandible). A JSON file was generated for each annotation., Results: The database encompassed 23,619 annotations; disagreement between radiologists occurred in 0.7% of the notes., Conclusions: This work aimed to inform researchers about the importance of the labeling process, in addition to providing the scientific community with a bank of labeled images to implement artificial intelligence systems in clinical practice., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Objective: To compare digital panoramic radiography (DPR) and cone beam CT (CBCT) in the detection and classification of pulp calcifications in posterior teeth in relation to tooth condition and its location., Methods: Two hundred and fifty patients with simultaneous DPR and CBCT scans were selected from a dental image bank. For each posterior tooth, its condition was registered (healthy, restored, or decayed). The presence of calcifications was assessed and classified according to location (coronal or radicular) and type (total obliteration, partial obliteration, narrowing, and no calcification). Chi-square and McNemar tests were used to compare DPR and CBCT results, with a significance level of 5%. DPR diagnostic values were calculated using CBCT as reference., Results: Decayed and restored teeth showed a significantly (P < .001) higher prevalence of pulp calcifications than healthy teeth in both imaging exams. There was a significant discrepancy between the imaging modalities in the identification of calcifications (P < .001), especially for radicular calcifications of maxillary teeth (DPR = 55.2%; CBCT = 30.9%). In the case of coronal calcifications, there was a greater discrepancy between CBCT and DPR in the mandibular teeth (10.7%) than in the maxillary teeth (7.7%). Overall, DPR presents higher sensitivity (0.855) than specificity (0.483) for pulp calcifications detection., Conclusion: DPR considerably overestimates pulp calcifications in posterior teeth, as compared to CBCT. A higher prevalence of pulp calcifications is related to decayed and restored teeth., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology and the International Association of Dentomaxillofacial Radiology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objective: To investigate the association of perforation of the maxillary sinus floor by dental implants with mucosal thickening and to describe its characteristics in perforated cases., Study Design: One-hundred and twenty-nine maxillary sinuses of 93 patients presenting 202 dental implants in the maxillary posterior region were retrospectively assessed in cone-beam computed tomography scans and classified according to maxillary sinus perforation, bone graft, mucosal thickening, and mucosal appearance. Logistic regression determined the chance of mucosal thickening in perforated maxillary sinuses. The chi-square test compared categorical variables between maxillary sinus perforated or not by implants and maxillary sinus with or without mucosal thickening. The significance level assumed was 5 % (α = 0.05)., Results: There was perforation of 60 maxillary sinuses floor (46.5 %) by 74 dental implants. The chance of mucosal thickening was higher when the implant tip was trespassing on the maxillary sinus floor (p < 0.001). There was a significant association between maxillary sinus mucosal thickening and perforation by a dental implant with the tip trespassing the maxillary sinus floor (p < 0.05)., Conclusion: Maxillary sinus mucosal thickening is associated with sinus floor perforation by dental implants and does not depend on the number of implants perforating it., Clinical Relevance: There is an association between dental implants' perforation of the maxillary sinus floor and the thickening of the maxillary sinus. In those cases, the appearance of the mucosa thickening may be irregular, local, or total opacification of the sinus cavity., Competing Interests: Declaration of competing interest The authors declare that they do not have any conflicts of interest related to this study., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objectives: This study evaluated the effect of metal artefact reduction (MAR) level and tube current on the assessment of dental implant positioning relative to the mandibular canal (MC) through cone-beam computed tomography (CBCT)., Methods: Titanium dental implants were placed in dried mandibles at 0.5-mm superior to the MC (group 1/n = 8) and 0.5-mm inside the MC with perforation of the cortex (group 2/n = 10). CBCT scans were obtained with different levels of MAR (off, medium, and high) and 2 tube currents (4 and 8 mA). Four examiners analysed the images and scored the contact between the implant and the MC using a 5-point scale. Sensitivity, specificity, area under receiver operating characteristic curve (ROC), and frequency of scores were calculated. Data were compared with analysis of variance 2-way and Tukey's test and scores with Chi-square test., Results: Specificity and area under ROC curve decreased significantly when MAR level was high compared with MAR-medium and MAR-off. The frequency of score 3 (inconclusive) was the highest, and scores 1 and 5 (definitely no contact and definitely contact, respectively) were the lowest with MAR-high, regardless of the tube current. When MAR was off, there were higher frequencies of scores 1 and 5., Conclusions: The level of MAR influences the assessment of the relationship between the dental implant and the MC. MAR-high led to lower diagnostic accuracy compared with MAR-medium and off., Advances in Knowledge: This article shows that high level of MAR can interfere in the diagnostic of dental implant positioning relative to the MC, decreasing its accuracy., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology and the International Association of Dentomaxillofacial Radiology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objective: To assess the accuracy and reproducibility of cephalometric landmark identification performed by 2 artificial intelligence (AI)-driven applications (CefBot and WebCeph) and human examiners., Study Design: Lateral cephalometric radiographs of 10 skulls containing 0.5 mm lead spheres directly placed at 10 cephalometric landmarks were obtained as the reference standard. Ten radiographs without spheres were obtained from the same skulls for identification of cephalometric points performed by the AI applications and 10 examiners. The x- and y-coordinate values of the cephalometric points identified by the AI applications and examiners were compared with those from the reference standard images using one-way analysis of variance and the Dunnet post-hoc test. The intraclass correlation coefficient (ICC) was used to evaluate reproducibility. Mean radial error (MRE) in identification was calculated with respect to the reference standard. Statistical significance was established at P < .05., Results: Landmark identification by CefBot and the examiners did not exhibit significant differences from the reference standard on either axis (P > .05). WebCeph produced a significant difference (P < .05) in 4 and 6 points on the x- and y-axes, respectively. Reproducibility was excellent for CefBot and the examiners (ICC ≥ 0.9943) and good for WebCeph (ICC ≥ 0.7868). MREs of CefBot and the examiners were similar., Conclusion: With results similar to those of human examiners, CefBot demonstrated excellent reliability and can aid in cephalometric applications. WebCeph produced significant errors., Competing Interests: Declaration of interests None., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: To identify local radiographic risk factors for Medication-Related Osteonecrosis of the Jaws (MRONJ) in osteoporotic patients treated with antiresorptive drugs (ARD) and undergoing tooth extraction., Material and Methods: Patients were included in this retrospective, longitudinal, case-control study, if having at least one administration of ARD, underwent tooth extraction(s), and had pre- and post-operative panoramic radiographs. Additionally, a matched control group was selected. Three calibrated, blinded, and independent observers assessed each tooth extraction site. Statistical analysis compared control against study group, and within the latter, sites MRONJ+ and MRONJ-., Results: In total, 120 patients (99 females/21 males) with 354 tooth extractions were included, from which nine patients (7.5%) and eleven tooth extraction sites (3.1%) developed MRONJ. When comparing control with study group, the latter showed significantly more thickened lamina dura, persistence of the alveolar socket, heterogeneous bone patterns, and sequestrum formation. In the study group, MRONJ developed significantly more in males (19%, p = 0.049), smokers (25%, p = 0.008), in the mandible (82%, p = 0.027), when identifying a radiolucent or sclerotic trabecular pattern (p = 0.004) or when extracting teeth with furcation involvement (p < 0.001), root remnants (p = 0.017), or unrestored caries lesions (p = 0.005)., Conclusions: Tooth extraction sites showing radiographic signs of chronic dental infection are prone to MRONJ., (© 2023 The Authors. Oral Diseases published by Wiley Periodicals LLC.)

Background: There is no established protocol for the low doses of cone-beam computed tomography (CBCT) acquisition and filter application on the diagnosis of condylar morphological alterations., Objectives: The objective of the study was to evaluate the influence of voxel size and filter application on the diagnosis of condylar morphological alterations in CBCT using an ex vivo model., Methods: CBCT scans of 36 temporomandibular joints were acquired using OP300 Maxio with voxel sizes of 0.085, 0.125 and 0.280 mm. Three radiologists evaluated the condyles in the CBCT volumes under three filter modes: no filter, '1x' sharpen filter and '2x' sharpen filter. The area under the ROC curve, sensitivity and specificity were calculated by comparing the evaluators' responses with the reference standard and compared among experimental groups using analysis of variance (ANOVA) (α = 5%)., Results: The area under the ROC curve, sensitivity and specificity were not affected by voxel size and filter application (p > .05). For osteophyte and flattening, there were more true-positive responses in smaller voxel size. For erosion, the increase of true- and false-positive responses occurred with a larger voxel size. Overall, there was a tendency to decrease true positives for osteophyte and erosion and increase false positives for flattening with the '2x' sharpen filter., Conclusions: The diagnosis of condylar morphological alterations assessed in this ex vivo analysis is not influenced by the voxel size and the application of the filters. However, attention is needed with the occurrence of false-positive diagnosis with a larger voxel size for erosion and '2x' sharpen filter for flattening., (© 2023 John Wiley & Sons Ltd.)

Objective: To investigate whether the curve markings performed prior to panoramic and cross-sectional reconstructions can influence the planning of oral implants., Methods: Twenty oral radiologists landmarked the reference panoramic curves in 25 CBCT scans of the mandible. Bone height was measured on the resulting cross-sectional slices in the edentulous region of the lower first molar. The following data were recorded: (1) number of landmarks used to build each reference curve; (2) shape of the reference curve (inverted "U", inverted "V" or "horseshoe"); and (3) measurement in the first molar region. The data were assessed for variability based on the number of landmarks, the shape of the reference curve, and the measurements obtained., Results: The number of landmarks used to guide the panoramic reconstruction varied among radiologists (p < 0.05), but most of them draw curves in inverted "U" shape (68-100%). The reproducibility of the measurements taken in the edentulous mandibular first molar region was excellent (84.7%). The number of landmarks and the shape of the curve did not have a significant influence on the reproducibility of the measurements (p > 0.05)., Conclusion: Variations of the operator-dependent steps during the panoramic reconstructions occur but do not play a significant part changing the measurements taken for oral implant planning., (© 2023. The Author(s) under exclusive licence to Japanese Society for Oral and Maxillofacial Radiology.)

Objective: The aim of this study was to evaluate the influence of binarization methods (BnMs) on the fractal dimension (FD) of the alveolar bone in digital radiographic images., Study Design: Five identical periapical radiographs were obtained from each of 20 anatomic regions. Using ImageJ/Fiji software, a standardized region of interest was positioned in the trabecular bone of all radiographs, 14 BnMs were independently applied, and FD was calculated. The Friedman test and Dunn post hoc tests were used to evaluate the influence of BnMs on FD (α = 0.05). The intraclass correlation coefficient (ICC) was used to assess correlation among BnMs., Results: No significant differences were observed in the threshold value between the BnMs. No significant differences in FD were observed among 9 BnMs (Default, Huang, Iso Data, Li, Mean, Min Error[I], Moments, Otsu, and Shanbhag). These methods presented significantly higher FDs than those from 3 other BnMs (Max Entropy, Renyi Entropy, and Yen), which did not significantly differ from each other. The Triangle method significantly differed from all BnMs, and the Percentile method produced significantly higher FDs than Huang, IsoData, Li, Moments, Otsu, and Shanbhag. Most BnMs presented good or excellent correlation (ICC ≥ 0.76)., Conclusions: Binarization methods influence FD of the alveolar bone from digital periapical radiographs; thus, this technical aspect is relevant for comparison purposes and should be standardized. For comparison of published FD research, the Default method is recommended., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Objective: The objective of this study was to evaluate the effects of spatial resolution and the application of enhancement filters in the diagnosis of simulated furcation defects and image quality with intraoral radiographs., Study Design: Periapical images were acquired with photostimulable phosphor plates of molars in dry skulls (n = 8) and mandibles (n = 10) with 4 stages of furcation defect simulation. The plates were scanned in fast scan and high resolution modes to produce different spatial resolutions. Four image filters were applied. Six observers scored the detection of furcation defects. Mean values of area under the curve in receiver operating characteristic evaluation, accuracy, sensitivity, and specificity were calculated. Mean gray value (brightness), noise, and contrast-to-noise ratio (CNR) were calculated for enamel, dentin, and alveolar bone to evaluate image quality. Analysis of variance compared the values between the different spatial resolutions and filters. The significance of difference was established at P < .05., Results: There were no significant differences in overall diagnostic values comparing image spatial resolutions and filters. Diagnostic outcomes were significantly better for the largest defects than the smallest lesions but were generally poor in detecting lesions. All structures showed greater brightness in high resolution. . Noise was greater in all structures with all enhancement filters except inversion. Dentin and alveolar bone exhibited more noise and lower CNR in high resolution., Conclusions: Varying spatial resolution and applying enhancement filters did not significantly affect the diagnosis of furcation defects., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to evaluate the influence of the extensive use of a photostimulable phosphor (PSP) receptor on the diagnosis of proximal carious lesions., Study Design: Forty posterior teeth were paired and mounted in 20 phantoms. Using a PSP receptor of the Express intraoral system, 1 radiograph of each phantom was acquired, totaling 20 radiographs (group 1). After 400 acquisitions, another radiograph of each phantom was obtained, totaling 20 new radiographs (group 2). This procedure was also done after 800 (group 3), 1,200 (group 4), and 1,600 (group 5) acquisitions, resulting in 100 radiographs. Another 40 radiographs (20 phantoms × 2 groups) were obtained with a second PSP sensor to evaluate the diagnostic replicability of the receptors. All 140 radiographs were assessed independently by 5 examiners for the presence of proximal caries. Area under the receiver operating characteristic curve, sensitivity, and specificity were calculated and compared among the groups by analysis of variance. The Student t test evaluated the diagnostic replicability of the receptors. The significance level was set at 5% (P < .05)., Results: The diagnostic outcomes for proximal caries did not differ among the groups (P ≥ .37). The diagnostic values did not differ among the radiographs acquired with the 2 PSP receptors (P ≥ .75)., Conclusions: The diagnosis of proximal carious lesions was not affected by extensive use of the PSP receptor., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Purpose: To assess radiographic presentation of anatomical structures, bony changes and soft tissue calcifications on panoramic radiographs of oncologic patients under high dose antiresorptive drug therapy (ART) before exposure to dental extraction., Methods: Panoramic radiographs of 57 patients under ART, taken previously to tooth extraction, and 57 control patients were evaluated by two oral radiologists regarding bone pattern, anatomical structures visibility, estimation of cortical width, mandibular cortical index (MCI), and presence of soft tissue calcifications. Parameters were compared between ART and age- and gender-matched healthy control groups. Bone patterns were further assessed by regions with or without tooth extractions and according to uneventful healing or MRONJ development. All comparisons were made using chi-square test with significance level set at 5%., Results: Mandible and posterior maxilla presented more sclerotic bone patterns in patients under ART, regardless of tooth extraction and MRONJ development status (p < 0.05). Heterogeneous bone pattern was identified in two regions that both were subsequently affected by MRONJ. Anatomical structure visibility and presence of soft tissue calcifications was not different among groups (p > 0.05). ART patients showed significantly more C0 (thickening) and C1 MCI (p < 0.05)., Conclusion: Sclerotic bone pattern and thicker mandibular cortices may represent a consequence of ART rather than MRONJ specific findings. Prospective studies on larger patient samples radiographically followed-up during the ART treatment are advised, with specific attention to heterogenous trabecular bone pattern as a possible MRONJ predictor., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: There is no established acquisition protocol based on scientific evidence for the acquisition of cone-beam computed tomography (CBCT) exams to evaluate the temporomandibular joint (TMJ)., Objectives: To evaluate the influence of acquisition protocols and jaw positioning on the diagnostic accuracy of TMJ condylar morphological alterations (CMA), dimension, position and excursion., Methods: Thirty-six TMJs on 18 dry skulls were imaged using a CBCT unit (OP300 Maxio, Instrumentarium, Tuusula, Finland) at two exposure settings (4.5 and 6.3 mA), three voxel resolutions (0.085, 0.125 and 0.280 mm), three jaw positions (concentric, anteriorised and posteriorised) and three jaw excursions (normoexcursion, hyperexcursion and hypoexcursion). The macroscopic anatomy examination and high-resolution CBCT images were used as ground truth for CMA. Twenty-five TMJs had at least one CMA with 11 healthy TMJs serving as controls. Three experienced oral and maxillofacial radiologists evaluated the parasagittal images for the presence of CMA, position and excursion and measured dimensions. The area under the ROC curve, sensitivity and specificity were calculated. Weighted Kappa (α = 0.05) was used to determine intra- and interexaminer reliability and comparisons between dependent variables analysed by Analysis of Variance at an a prior level of significance of 0.05., Results: The agreement of the evaluation of the position and excursion with the reference standard was high, independent of the protocol (range, 0.75-0.91). Various combinations of acquisition protocols and jaw position did not influence the CMA evaluation. Erosion was overdiagnosed in protocols with larger voxel sizes and the detection of osteophytes greater in images with smaller voxel sizes. The anteroposterior dimension was greater in the open jaw position (p < .05)., Conclusion: CBCT protocols using reduced radiation exposure from the CBCT machine evaluated in this study can be used to assess condylar morphology, dimension, position and excursion, without compromising diagnostic performances for these parameters., (© 2022 John Wiley & Sons Ltd.)

Objective: To evaluate whether the automatic exposure compensation in the presence of high-density materials can affect the measurement of alveolar bone level., Methods: Thirty regions of seven dry skulls and six mandibles were radiographed with and without a high-density material, using two digital radiographic technologies: photostimulable phosphor plate (PSP, Digora Optime) and sensor (CMOS, Digora Toto), totaling 120 images. The distances from the cement-enamel junction to the alveolar bone crest were measured using cone-beam computed tomography (CBCT) images to represent the reference standard. The same measurements of alveolar bone level and the average of the pixel values of the image were evaluated on the radiographs. Paired t test compared the average pixel values and alveolar bone-level measurements between images with and without high-density material. One-way analysis of variance compared the difference between radiographic and CBCT measurements (α = 0.05)., Results: The high-density material reduced the pixel values in PSP (p = 0.002) and CMOS (p < 0.001) technologies, demonstrating the AEC functioning in both technologies. There was no difference in bone-level measurements between the images without and with the high-density material for both technologies (p ≥ 0.091), or between the tomographic and radiographic measurements (p ≥ 0.319)., Conclusion: In the presence of high-density material, the automatic exposure compensation reduces the average pixel values of the images (i.e., images get darker), but does not influence the radiographic measurements of alveolar bone level., (© 2022. The Author(s) under exclusive licence to Japanese Society for Oral and Maxillofacial Radiology.)

Purpose: To evaluate the influence of the milliamperage and artifact reduction (AR) tool on the diagnosis of buccal and lingual peri-implant dehiscences related to titanium-zirconia (Ti-Zr) and zirconia (Zr) implants using CBCT images., Materials and Methods: Ti-Zr and Zr implants were alternately inserted in 20 sites in the posterior region of three human mandibles that presented intact cortical (control) bones or simulated buccal and/or lingual peri-implant dehiscences. CBCT images were acquired with an OP300 Maxio unit, varied milliamperage (5 and 8 mA), and the use of AR tool. Three oral radiologists assessed the presence of dehiscences using a 5-point scale. The area under the receiver operator characteristic curve (Az), sensitivity, and specificity of each group (control and dehiscence) were obtained and compared using multiway ANOVA (α = .05)., Results: The milliamperage and the AR tool did not influence the diagnosis of dehiscences, and there were no differences between the buccal and lingual cortices (P > .05). However, Zr implants showed a higher sensitivity (0.67 to 0.89) and lower specificity (0.26 to 0.44) than Ti-Zr implants (0.19 to 0.44 and 0.93 to 1.00, respectively; P < .05). Az values did not differ between the implant types (P > .05)., Conclusions: Dehiscences were more detectable when related to Zr implants, while the absence of dehiscences was more correctly visualized adjacent to Ti-Zr implants. The use of varied milliamperages and the AR tool did not affect the diagnosis of peri-implant dehiscences, regardless of the involved cortical (buccal or lingual) bones.

Tooth extraction is a risk factor for the development of osteonecrosis of the jaw following treatment with antiresorptive drugs (ARDs), but not all extraction sites develop this pathology. Therefore, we aimed to identify local radiographic predictors of Medication-Related Osteonecrosis of the Jaw (MRONJ) in panoramic images of oncologic patients undergoing tooth extraction. Based on a retrospective longitudinal cohort study design, patients were included if undergoing one or more tooth extraction, with at least one administration of ARDs, and presence of pre- and post-operative panoramic radiographs. After data collection, blinded and independent observations were performed. Eleven distinct imaging-related parameters were assessed preoperatively and five postoperatively, at each extraction site. A case-control and subgroup analysis assessing MRONJ development was performed. Significance level is set to 0.05 (5%). A total of 77 oncologic patients were selected, undergoing 218 tooth extractions, from which 63 teeth (29%) in 39 patients (51%) developed MRONJ. Results showed that patients developed significantly more MRONJ with longer ARD treatment (p = 0.057), teeth with absent and incomplete endodontic fillings with caries, widened periodontal ligament space and/or periapical lesions (p = 0.005), and sclerotic and heterogenous bone patterns (p = 0.005). In conclusion, tooth extraction sites presenting with infections and bone sclerosis are at higher risk to develop MRONJ., (© 2022. The Author(s).)

Objectives: To evaluate the influence of digital filters of intraoral radiographic systems on the diagnosis of simulated internal and external root resorptions and image quality., Materials and Methods: Internal root resorption (IRR) and external root resorption (ERR) were simulated in 34 teeth. For image acquisition, two radiographic systems were used: Digora Toto and VistaScan. All filters available in these systems were applied. Three observers scored the detection of root resorptions in a 5-point scale. The noise and the contrast-to-noise ratio (CNR) were calculated. The area under ROC curve, sensitivity, specificity, and accuracy were obtained. One-way ANOVA with Tukey's post hoc tests compared the diagnostic values, noise, and CNR between the filters (α = 0.05)., Results: For ERR, there were no significant differences in diagnostic values between the filters tested for both systems. For IRR, Original and Noise Reduction filters presented higher sensitivity than the Sharpen2 filter for images from Digora Toto, with no differences between the other groups. For VistaScan, there were no significant differences of diagnostic values between the groups studied. Noise values differed among the filters of both systems. The CNR of the filters differed only for the bone region for Digora Toto, while for VistaScan, both tooth and bone regions differed., Conclusions: Despite promoting changes in pixel intensities and affecting the noise level of the radiographic images, the digital filters of Digora Toto and VistaScan systems do not affect the diagnosis of internal or external root resorptions., Clinical Relevance: Digital filters are common tools in digital radiographic systems and may be used by the professional without impairment in root resorptions diagnosis., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: To investigate the performance of radiographic systems with automatic exposure compensation (AEC) on the caries diagnosis in images acquired with different exposure parameters and in the presence of high-density material. Also, the image quality was assessed., Methods: Forty posterior teeth (80 proximal surfaces) were radiographed using a phosphor plate and a CMOS system. Images were acquired with different exposure times (0.06, 0.10 and 0.16 s) and kilovoltages (60 and 70kVp), in the absence and presence of high-density material in the X-rayed region (control and high-density groups). Five radiologists assessed the caries using a 5-point scale. Diagnostic values were compared using two-way ANOVA., Results: For both radiographic systems, there were no significant differences in the area under the ROC curve (0.60-0.73), sensitivity (0.79-0.87) and specificity (0.29-0.48) between the control and high-density groups, exposure times or kilovoltages (p > 0.05). For image quality, scores assigned to the control and high-density groups were similar in each exposure protocol in both systems., Conclusions: The presence of high-density material, exposure time and kilovoltage did not affect the caries diagnosis in any of the systems tested. It is recommended to use protocols with lower doses to reduce the patient's exposure., (© 2021. The Author(s), under exclusive licence to Japanese Society for Oral and Maxillofacial Radiology and Springer Nature Singapore Pte Ltd.)

Objectives: To assess the influence of sagittal and vertical skeletal patterns, and sex in the angulation and relationship between the maxillary central incisors and the nasopalatine canal., Materials and Methods: Cone-beam computed tomography (CBCT) exams of 172 patients were classified into sagittal (class I, II, and III) and vertical skeletal patterns (mesofacial, brachyfacial and dolichofacial). Hard palate-nasopalatine canal and hard palate-long axis of maxillary central incisors angles were measured in sagittal reconstructions. The obtained angles were used to calculate the angulation between maxillary central incisors and nasopalatine canal by triangle geometric relationship. Analysis of variance (multi-way ANOVA) and Tukey post-hoc test were used for data analysis (α=5%)., Results: Sagittal and vertical skeletal patterns, and sex presented a low influence on the angulation of maxillary central incisors and nasopalatine canal. Dolichofacial class II women showed the greatest hard palate-nasopalatine canal angulations (P<0.05) and maxillary central incisors and nasopalatine canal angulations (P<0.05). Mesofacial class II and III men presented the lowest maxillary central incisors and nasopalatine canal angulations (P<0.05)., Conclusions: The sagittal and vertical skeletal patterns, and sex have a low influence on the angulation of the maxillary central incisors and the nasopalatine canal., (Copyright © 2022 CEO. Published by Elsevier Masson SAS. All rights reserved.)

Objective: To map the shape, location, and thickness of the focal trough of a panoramic radiography device with a multilayer imaging program., Methods: An acrylic plate (148 × 148 × 3 mm) containing 1156 holes distributed in a matrix of 34 × 34 rows was placed in the OP300 Maxio at the levels of the maxilla and mandible. 20 metal spheres (3.5 mm in diameter) were placed on the holes of the plate under 15 different arrangements and panoramic images were acquired for each arrangement at 66 kV, 8 mA, and an exposure time of 16 s. The resulting panoramic radiographs from the five image layers were exported, the horizontal and vertical dimensions of the metal spheres were measured in all images using the Image J software, and the magnification and distortion rates of the spheres were calculated. All metal spheres presenting a magnification rate lower than 30% in both vertical and horizontal dimensions and a distortion rate lower than 10% were considered to map the focal troughs of each of the five image layers., Results: All panoramic image layers had a curved shape ranging from 39° to 51° for both dental arches and varied in position and thickness. The anterior region of maxilla was anteriorly displaced when compared to the anterior region of the mandible for all layers. Image layers are thicker at the level of the mandible than those at the level of the maxilla; also, inner layers were thinner and outer layers were thicker., Conclusion: All image layers in the studied panoramic radiography device had a curved shape and varied in position and thickness. The anterior region of maxilla was anteriorly displaced when compared to that of the mandible for all layers.

Objective: To assess the reproducibility of a wedge-guided bitewing image receptor-holding device (IRHD-WG) compared to a commercially available bitewing image receptor-holding device (IRHD-XCP)., Methods and Materials: Ten operators randomly acquired bitewing radiographs of four posterior regions (Premolar, Molar 1, Molar 2, Molar 3) distributed in two dry bone skulls and mandibles using 2 IRHDs (IRHD-WG and IRHD-XCP). The radiographs corresponding to the same region and IRHD but acquired by different operators were paired for reproducibility comparison. A total of 360 pairs of radiographs were randomized for analysis. Objective analysis consisted of extracting the pixel values from each radiograph and comparing the values between each pair by intraclass correlation coefficient. For subjective analysis, the IRHDs images were digitally removed. Five oral radiologists blinded for the study conditions classified the radiograph pairs according to their similarity and diagnostic value. The answers' relative frequencies were compared by the chi-square test (α = 0.05)., Results: The IRHD-WG presented a higher reproducibility (Mean = 0.850; SD = 0.144) than the IRHD-XCP (Mean = 0.615; SD = 0.287) in the objective analysis. Radiographs acquired with the IRHD-WG were more similar than those acquired with the IRHD-XCP ( p < 0.001). The diagnostic value of bitewing radiographs acquired with the IRHD-WG was considered superior to those acquired with the IRHD-XCP ( p < 0.001)., Conclusion: For the objective and subjective analyses of reproducibility, the IRHD-WG performed better than the commercial IRHD-XCP.

Objective: To investigate whether the use of cone beam CT (CBCT) changes the diagnosis of external root resorption (ERR) or marginal bone loss (MBL) involving a second molar adjacent to an impacted third molar., Methods: A systematic search was applied in PubMed, EMBASE, Scopus, Web of Science, LILACS, Google Scholar, OpenGrey, and ProQuest. Studies assessing the detection of ERR or MBL in a second molar adjacent to an impacted third molar through CBCT and panoramic radiography (PAN) were included. Prevalence and agreement between PAN and CBCT on the detection of ERR and MBL were collected. The risk of bias was assessed using the MAStARI., Results: A total of 593 papers were identified, and after a 2-phase selection, 5 studies were included in the narrative synthesis. Regarding ERR, its prevalence in PAN was reported from 5.31 to 19.5% and from 22.8 to 62.0% in CBCT. The percentage of agreement varied from 28.5 to 74.0%. The prevalence of MBL varied from 21.9 to 62.9% in PAN, while those values varied from 21.6 to 80% in CBCT images. The percentage of agreement between PAN and CBCT for the detection of MBL ranged from 66.0 to 85.0%. Four studies presented low risk of bias and one had moderate risk., Conclusions: More ERR and MBL are assessed in CBCT compared to PAN. There is a considerable agreement between PAN and CBCT assessment of ERR and MBL, however, mostly related to the absence of the pathology rather its presence.

Background: This study aimed to investigate the effect of automatic exposure compensation (AEC) of intraoral radiographic systems on the gray values of dental tissues in images acquired with or without high-density material in the exposed region using different exposure times and kilovoltages. The influence of the distance of the high-density material was also investigated., Methods: Radiographs from the molar region of two mandibles were obtained using the RVG 6100 and the Express systems, operating at 60 and 70 kV and 0.06, 0.10, and 0.16 s. Subsequently, a titanium implant was inserted in the premolar's socket and other images were acquired. Using the ImageJ software, two regions of interest were determined on the enamel, coronary dentine, root dentine, and pulp of the first and second molars to obtain their gray values., Results: In the RVG 6100, the implant did not affect the gray values (p > 0.05); the increase in kV decreased it in all tissues (p < 0.05), and the exposure time affected only the root dentine and pulp. In the Express, only enamel and coronary dentine values changed (p < 0.05), decreasing with the implant presence and/or with the increase in exposure factors. The distance of the implant did not affect the results (p > 0.05)., Conclusions: AEC's performance varies between the radiographic systems. Its effect on the gray values depends not only on the presence or absence of high-density material but also on the kV and exposure time used., (© 2022. The Author(s).)

Objectives: The present study aimed to assess whether anatomical variations of the mandibular canal are associated with neurosensory disturbances of the inferior alveolar nerve (IAN) following mandibular third molar removal., Methods: Two observers compared the detection of third molar root-nerve relations and bifurcations of the mandibular canal on panoramic radiographs and CBCT images of 201 patients undergoing removal of 357 mandibular third molars. Potential neurosensory disturbances of the IAN were surveyed ten days after surgery. Fisher's Exact was performed to correlate presence of canal variations to postoperative neurosensory disturbances. Positive and negative predictive values (PPV, NPV) and likelihood ratios (LR + , LR-) were calculated., Results: Thirteen patients reported postoperative altered sensation of the lower lip, with 2 of them having mandibular canal bifurcations on the ipsilateral side of the injury. Fisher's Exact showed that the studied mandibular canal variations were not related to postoperative neurosensory disturbances. CBCT was superior in visualization of anatomical variations of the mandibular canal. Prevalence of bifurcations was 14% on CBCT and 7% on panoramic radiographs. In both imaging modalities and for all parameters, PPVs were low (0.04 - 0.06) and NPVs were high (0.92 - 0.98), with LR ranging around 1., Conclusion: In the present study, the assessed mandibular canal variations had limited predictive value for IAN neurosensory disturbances following third molar removal., Clinical Relevance: While a close relation between the third molar and the mandibular canal remains a high risk factor, mandibular canal variations did not pose an increased risk of postoperative IAN injury after third molar removal., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The objectives of the present study were to compare measurements of pharyngeal airway subregions on lateral cephalometric (LC) and cone beam computed tomographic (CBCT) images in relation to skeletal classes and discuss the advantages and disadvantages of these imaging formats for this type of assessment. The CBCT images were assessed via both multiplanar reconstruction (MPR) and 3-dimensional (3D) reconstruction. The LC and CBCT images from 107 patients were classified according to skeletal class: I, n = 35; II, n = 35; and III, n = 37. Linear measurements of the subdivisions of the upper airway were performed on the LC, MPR, and 3D images. In addition, area and volumetric measurements were performed on the MPR images. The relationships among imaging methods, skeletal class, and pharyngeal thirds were assessed by means of a 1-way analysis of variance (α = 0.05). No statistically significant differences in the linear, area, or volumetric measurements of the upper airway subregions were found among the skeletal classes (P > 0.05). For the linear measurements in the oropharynx and hypopharynx, greater values were observed for the LC images than for the MPR and 3D images (P ≤ 0.05). Based on the study findings, MPR images should be preferred for visualization of the pharyngeal airway subregions. However, LC imaging is preferable to 3D reconstruction., Competing Interests: The authors report no conflict of interest pertaining to any of the products or companies discussed in this article.

Objectives: The objective of this study was to assess the influence of ambient lighting levels and horizontal viewing angle (HVA) on the radiographic detection of fractured endodontic instruments in root canals in extracted human mandibular molars., Study Design: Thirty-two root canals were selected. Endodontic instrument fracture was induced in 24 canals, and all canals were endodontially treated. Periapical radiographs were obtained at orthoradial, mesioradial, and distoradial projection angles. Five oral radiologists examined the radiographs for detection of fractured endodontic instruments under 3 ambient lighting levels (high, 450 lux; medium, 28 lux; and low, 2.5 lux) and 3 HVAs (90°, 67.5°, and 45°). Area under the receiver operating characteristic curve (AUROC), accuracy, sensitivity, and specificity were calculated and compared by 2-way analysis of variance using Tukey post hoc tests (α = .05)., Results: AUROC data indicated that ambient lighting (P = .739) and HVA (P = .238) did not significantly influence the detection of fractured endodontic instruments. Overall mean diagnostic values were 0.745, 0.57, 0.46, and 0.90 for AUROC, accuracy, sensitivity, and specificity, respectively., Conclusions: The viewing conditions assessed in this study did not influence the radiographic detection of fractured endodontic instruments in root canals., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objectives: To assess whether dimensional changes occur as shape distortion (unevenly), contraction or magnification (evenly) in cone beam computed tomography (CBCT) considering materials, anatomical regions and metal artefact reduction algorithms., Methods: Four cylinders of amalgam (Am), cobalt-chromium (Co-Cr), gutta-percha (Gu), titanium (Ti) and zirconium (Zi) were inserted inside a polymethylmethacrylate phantom in anterior and posterior regions for acquisitions in Picasso Trio and OP300 with MAR enabled and disabled. Two observers measured the dimensions of each cylinder in three axes: Y (height), Z (antero posterior diameter) and X (latero-lateral diameter). Repeated measures ANOVA with Tukey post-hoc test compared the data (α = 5%)., Results: Shape distortion occurred for all materials in anterior region of Picasso Trio without MAR ( p < 0.05). With MAR enabled, Gu and Ti contracted ( p ≥ 0.05), while the others showed distortion ( p < 0.05). In posterior region, all materials distorted in both MAR conditions ( p < 0.05), except Gu, which magnified without MAR ( p ≥ 0.05) and contracted unevenly with MAR ( p < 0.05). In anterior region of OP300, all materials magnified without MAR, ( p ≥ 0.05) and had shape distortion with MAR ( p < 0.05). In posterior region, only Am showed magnification without MAR ( p ≥ 0.05), while all materials presented shape distortion with MAR ( p < 0.05)., Conclusion: Dimensional changes of high-density materials in CBCT can be either a magnification, a contraction or a distortion; the last condition is the most prevalent. Furthermore, changes differ considering material, anatomical region and MAR condition.

Objectives: This in vitro study aimed to evaluate the influence of the radiographic image file format and the transmission application (app) on the diagnosis of proximal caries lesions., Study Design: Twenty bitewing radiographs of 40 posterior human teeth placed in phantoms were acquired using the Digora Toto digital sensor. All images were exported as TIFF (Tagged Image File Format), BMP (Windows Bitmap), PNG (Portable Network Graphics), and JPEG (Joint Photographic Experts Group) and transmitted online via WhatsApp and Messenger. Five examiners evaluated the radiographs with no online transmission and as transmitted through the 2 apps for the presence of proximal caries lesions using a 5-point scale. The reference standard for caries lesions was established using micro-computed tomography. Two-way analysis of variance compared values of sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (α = .05). The kappa test was used to assess intra- and interexaminer agreement., Results: Sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve values showed no significant differences in the diagnosis of proximal caries lesions between the different image file formats (P ≥ .773) and transmission apps (P ≥ .608). Intraexaminer agreement was substantial (κ = 0.742) and interexaminer agreement was moderate (κ = 0.475)., Conclusion: The digital file format and transmission app did not influence the radiographic diagnosis of proximal caries lesions., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: To evaluate the influence of sagittal and vertical skeletal patterns (skeletal classes and facial profiles), and sex on the distance between upper central incisors roots and incisive canal., Material and Methods: Cone-beam computed tomography exams of 172 patients were classified into skeletal classes I, II, and III and according to the facial profile into mesofacial, brachyfacial, and dolichofacial. In sagittal reconstructions, linear measurements were done between central incisors roots and incisive canal at three levels: incisive foramen opening, intermediate region, and the region close to the apex of upper central incisors. In axial reconstructions, measurements of incisive canal width and distance between the roots were obtained. Analysis of Variance (three-way ANOVA) was used to evaluate measurement differences in relation to skeletal classes, facial profiles, and sex., Results: The distance between upper central incisors roots and incisive canal anterior region was little influenced by sagittal and vertical skeletal patterns and sex. Men had significantly greater incisive canal (mean=2.85mm; SD=1.18) width compared to women (mean=2.40mm; SD=1.04), regardless of skeletal class and facial profile (P<0.05). In general, inter-root distance between medial points of central incisors roots and incisive canal opening was greater in the region close to upper central incisors apex (mean=3.84mm; SD=1.44) than in incisive foramen opening (2.44mm; SD=1.04), (P<0.05)., Conclusions: The distance between upper central incisors roots and incisive canal is little influenced by sagittal and vertical skeletal patterns and sex., (Copyright © 2021 CEO. Published by Elsevier Masson SAS. All rights reserved.)

Objectives: This study aimed to evaluate the influence of the number of basis images and the metal artifact reduction (MAR) tool on the production of artifacts near and far from a zirconium implant in cone-beam computed tomography (CBCT)., Materials and Methods: CBCT scans of a mandible were acquired before and after insertion of an implant, using 450 and 720 basis images, with and without MAR activation. The mean and standard deviation (SD) of the gray values of the regions of interest (ROIs) located on the cortices adjacent to the implant and at different distances from it (in the soft tissue) were calculated. The mean of the gray values was used to calculate the absolute contrast difference (ACD) between the control and implant scans., Results: In general, the number of basis images did not affect the SD and the ACD values of the buccal and lingual ROIs (p > 0.05). The implant increased the SD in the lingual cortical plate (p < 0.05). In this case, MAR activation decreased SD (p < 0.05). All ROIs located at different distances from the implant showed higher SD on scans acquired with 450 basis images (p < 0.05), regardless of MAR condition., Conclusions: A higher number of basis images reduces the magnitude of artifacts but does not influence the image quality in bone cortical plates. MAR improves the image in the areas most affected by artifacts., Clinical Relevance: The number of basis images is known as a factor capable of influencing the image quality and radiation dose for the patient. Therefore, it is important to investigate its effect on the expression of artifacts in the CBCT images., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Objectives: To evaluate the effect of cone-beam computed tomography (CBCT) tube current (mA) on the magnitude of artefacts at different distances from titanium or zirconia implants, with and without activation of a proprietary metal artefact reduction (MAR)., Material and Methods: Human mandibles were scanned on an OP300 Maxio CBCT unit (Instrumentarium, Tuusula, Finland) before and after the installation of dental implants, with four different tube currents (4 mA, 6.3 mA, 8 mA and 10 mA), with and without activation of proprietary MAR. The effect of mA on the standard deviation (SD) of gray values and contrast to noise ratio (CNR) were assessed in regions of interest located 1.5 cm, 2.5 cm, and 3.5 cm from implants., Results: In the presence of titanium implants, a significant decrease in SD was found by increasing tube current from 4 mA to 6.3 mA or 8 mA. For zirconia implants, 8 mA yielded better results for all distances. MAR improved CNR in the presence of zirconia implants at all distances, whereas no differences were observed with the use of MAR for titanium implants., Conclusion: Increased tube current can improve overall image quality in the presence of implants, at all the distances tested. When a zirconia implant is present, such increase in mA should be higher in comparison to that for examinations with titanium implants. Activation of OP300 Maxio proprietary MAR improved image quality only among examinations with zirconia implants., Clinical Relevance: Artefact-generating implants are common in the field of view of CBCT examinations. Optimal exposure parameters, such as tube current, ensure high image quality with lowest possible radiation exposure., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Objectives: To evaluate the influence of different image file formats of digital radiographic images on the diagnosis of external (ERR) and internal root resorption (IRR)., Materials and Methods: Thirty-four human teeth were selected. For ERR, 20 teeth were used (10 control and 10 with simulated ERR), and for IRR, 14 teeth were used (before and after IRR simulation). Digital periapical radiographs were acquired using the Digora Toto system and exported in four different image file formats: TIFF, BMP, PNG, and JPEG, totaling 192 radiographs. Five examiners evaluated the images using the JPEGView software and scored the detection of ERR or IRR on a 5-point scale. Sensitivity, specificity, accuracy, and the area under the ROC curve were obtained for the diagnosis of ERR and IRR in the different image file formats. Two-way ANOVA compared the diagnostic values between the file formats and the Kappa test assessed intra- and inter-examiner agreement. The significance level was set at 5% (α = 0.05)., Results: The mean values of intra-examiner agreement were substantial (0.740) for ERR and almost perfect (0.836) for IRR and, inter-examiner was fair (0.263) and moderate (0.421), respectively. No statistically significant differences were found among the different file formats for the diagnostic values of ERR and IRR., Conclusion: The file format of digital radiographs does not influence the diagnosis of ERR and IRR., Clinical Relevance: Digital radiographic images may be susceptible to computational factors; however, they can be stored in multiple file formats without affecting the diagnosis of dental root resorptions., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Objectives: This study aimed to evaluate the detection rate of apical radiolucencies in 2-dimensional images using cone-beam computed tomography (CBCT) as the reference standard, and to determine which factors related to the apical radiolucencies and the teeth could influence its detection., Materials and Methods: The sample consisted of exams of patients who had panoramic (PAN) and/or periapical (PERI) radiography and CBCT. The exams were assessed by 2 oral radiologists and divided into PAN+CBCT (227 teeth-285 roots) and PERI+CBCT (94 teeth-115 roots). Radiographic images were evaluated for the presence of apical radiolucency, while CBCT images were assessed for presence, size, location, and involvement of the cortical bone (thinning, expansion, and destruction). Diagnostic values were obtained for PERI and PAN., Results: PERI and PAN presented high accuracy (0.83 and 0.77, respectively) and specificity (0.89 and 0.91, respectively), but low sensitivity, especially for PAN (0.40 vs. 0.65 of PERI). The size of the apical radiolucency was positively correlated with its detection in PERI and PAN ( p < 0.001). For PAN, apical radiolucencies were 3.93 times more frequently detected when related to single-rooted teeth ( p = 0.038). The other factors did not influence apical radiolucency detection ( p > 0.05)., Conclusions: PERI presents slightly better accuracy than PAN for the detection of apical radiolucency. The size is the only factor related to radiolucency that influences its detection, for both radiographic exams. For PAN, apical radiolucency is most often detected in single-rooted teeth., Competing Interests: Conflict of Interest: No potential conflict of interest relevant to this article was reported., (Copyright © 2021. The Korean Academy of Conservative Dentistry.)

In some clinical situations, the installation of four or more dental implants may be infeasible. Therefore, the installation of protocol-type prostheses with only three implants may be necessary. The mechanical failures can hinder the success of the rehabilitation treatment., Objective: To evaluate and compare the mechanical stress of the metallic prosthetic bar when installed over protocol-type prostheses of three and four implants, and to evaluate the stress on the dental implants., Methodology: Two three-dimensional human jaw models were created. In one model, four dental implants (P4) were designed and in the other model three dental implants (P3) were designed. In both models, according to the arrangement of the dental implants, prosthetic bars were designed. In a finite element analysis software, compressive forces were applied to the ends of both prosthetic bars, simulating the force application during mastication. Tension and stress dissipation were analyzed on the prosthetic bar and dental implants., Results: Both P4 and P3 protocol-type prostheses supported the force efficiently without breaking the bar or the implants. Force dissipation along the bar was more homogeneous in the P3 prosthetic bar than in P4. In addition, P3 implants received a higher concentration of stress in relation to P4 implants., Conclusions: Prosthetic bars and dental implants withstand the stress of load application in both four and three implant protocol-type prostheses. Three-implants protocol showed more satisfactory force dissipation than the four-implant protocol., (© 2021 Craniofacial Research Foundation. Published by Elsevier B.V. All rights reserved.)

Objectives: To evaluate the influence of artefacts in cone beam CT (CBCT) images of filled root canals in isthmus-containing molars., Methods: 10 teeth presenting canals with an isthmus were instrumented and filled with a thermoplasticised obturation technique. The teeth were scanned using a micro-CT device and two CBCT devices: 3D Accuitomo 170 (ACC) and NewTom VGi evo (NT), with different acquisition protocols: larger and smaller voxel size. Three examiners assessed the CBCT images for: (1) detection of filling voids; (2) assessment of under- or overestimation of the filling material and (3) resemblance of CBCT images to the reference standard. Analyses of Task 1 yielded accuracy, sensitivity and specificity for detection of filling voids. For tasks 2 and 3, statistical analysis was performed using Wilcoxon test. The level of significance was set at p < .05., Results: For Task 1, ACC showed higher sensitivity, whereas NT presented higher specificity. No significant difference was found between the protocols in ACC, however, for NT, differences between protocols were significant for all diagnostic values. In Task 2, visualisation of the filling was overestimated for NT, while for ACC, underestimation was observed. For Task 3, images with smaller voxel size were more similar to the reference image, for both CBCT devices., Conclusions: Different artefacts compromise the detection of filling voids on CBCT images of canals in mandibular molars with isthmus. ACC and NT present rather similar diagnostic accuracy, even though artefact expression remains device-specific.

Introduction: The purpose of this preliminary study was to evaluate the diagnostic accuracy of the combined use of 2 cone-beam computed tomographic (CBCT) volumes obtained with the tooth of interest positioned at different orientations in the detection of vertical root fracture (VRF)., Methods: Thirty single-rooted teeth were divided into 2 main groups (n = 15): control and with VRF. The teeth were individually placed in a phantom composed of a human skull and mandible, which was CBCT scanned in 2 spatial orientations: conventional (with the Frankfurt plane parallel to the floor) and angled acquisition (tilted 90° backward). Also, each tooth was scanned with gutta-percha, a metal post, and without any intracanal material. Three oral radiologists individually evaluated the images resulting from conventional acquisition and verified the presence or absence of VRF (conventional CBCT assessment), setting a score on a 5-point scale. Subsequently, the observers evaluated both images resulting from the conventional and angled acquisitions (combined CBCT assessment). The diagnostic values of the conventional and combined assessments were compared using 2-way analysis of variance with the post hoc Tukey test. The significance level was set at 5% (α = 0.05)., Results: The combined CBCT assessment showed higher accuracy and sensitivity in the VRF diagnosis of teeth filled with gutta-percha (P < .05). In teeth with a metal post, all diagnostic values were higher in the combined CBCT assessment (P < .05)., Conclusions: This preliminary study suggests that the CBCT-based diagnosis of VRF in teeth with intracanal material was improved when the assessment combines images obtained at 2 orientations., (Copyright © 2021 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Objective: This article aims to appraise how scientific evidence related to CBCT has changed over the years, based on levels of evidence and diagnostic efficacy., Methods: A general search strategy was used in different databases (Pubmed, Embase, and Web of Science) to identify systematic reviews (SRs) on CBCT until November of 2020. The SRs included were divided according to different specialties of dentistry. A critical review of the articles was made, describing the level of evidence and efficacy., Results: In total, 75 articles were selected. There was an increase in the number of SRs on CBCT from 2014 onwards, as 83% of the SRs on this topic were published after 2013, and 72% between 2016 and to date. Twenty SRs (27%) performed meta-analysis. Only 28% of the SRs provided a detailed description of CBCT protocols. According to SR evidence, almost all specialties of dentistry have advanced concomitantly with the introduction of CBCT. The majority of SRs were related to clinical applications (level 2 of efficacy), followed by technical parameters (level 1 of efficacy). Only some CBCT models were mentioned in the SRs selected., Conclusion: Over the course of 20 years, SRs related to CBCT applications for a broad range of dental specialties have been published, with the vast majority of studies at levels 1 and 2 of diagnostic efficacy. Not all CBCT models available on the market have been scientifically validated. At all times, one should remain cautious as such not to simply extrapolate in vitro results to the clinical setting. Also, considering the wide variety of CBCT devices and protocols, reported results should not be overstated or generalized, as outcomes often refer to specific CBCT devices and protocols.

Objective: To create and validate two new Image Receptor-Holding devices (IRHDs) to reduce proximal surfaces overlapping in bitewing radiography in comparison to a regular well-established and commercially available IRHD., Methods: Two IRHDs for bitewing radiographs with a wedge on the biting surface were designed and 3D-printed. These IRHDs, with a large wedge (Pr-Lw) and small wedge (Pr-Sw), were compared with a regular commercially available IRHD (Rinn XCP ® ) during image acquisition of bitewing radiographs of four posterior regions (one upper region and three lower regions) in two dry skulls and mandibles. A total of 156 interproximal regions on bitewing radiographs were radiographed by 13 oral radiology graduate students and independently assessed by two oral radiologists (10 years of experience). IRHDs were compared by Cochran's Q test regarding the number of overlapped proximal surfaces in the acquired radiographs with a significance level of 5%., Results: The observers were in perfect agreement (κ = 1.0) to classify the proximal surfaces overlapping. The Pr-Lw IRHD presented the lowest number of surfaces overlapping (19.2%) followed by the Pr-Sw IRHD (48.1%) and the XCP ® IRHD with the highest surfaces overlapping (71.2%). The Pr-Lw IRHD surfaces overlapping was statistically different from the XCP IRHD ( p < 0.001), and the Pr-Sw IRHD ( p = 0.014)., Conclusions: The Pr-Lw IRHD demonstrated the most efficient performance in overlapping surfaces reduction, compared with the Pr-Sw IRHD and the XCP ® IRHD in adult dry skulls and mandibles.

Objectives: This study observed whether changes in diagnosis caused by analysis of three-dimensional images can lead to alterations in the treatment plans of impacted lower third molars (ILTMs)., Methods: Sets of panoramic (PAN) - cone beam computed tomography (CBCT) of 218 patients were assessed for ILTM classification, contact with mandibular canal, contact and resorption of the lower second molar (LSM), intraoperative planning and post-operative expectations., Results: Percentage agreement and McNemar test compared PAN vs CBCT assessments. Logistic regression analyzed the dependency of change in surgical planning considering the changes in diagnostic features; descriptive statistics was used to observe the expectation of post-operative complications and paresthesia. Differences were found between PAN vs CBCT for classification of impaction and positioning, LSM relationship, choice for crown and root sectioning and expectation of post-operative complications (all with p < 0.001). Logistic regression indicated that the change in diagnosis caused by CBCT examination did not change the clinical decision to extract ILTM but altered the planning of intraoperative steps such as osteotomy, crown sectioning and relaxing incision. The expectation of post-operative complications decreased when professionals planned the ILTM removal using tri-dimensional images., Conclusions: We concluded that changes in the diagnosis after CBCT examination can lead to alterations in the treatment plan of impacted lower third molar.

Objective: To evaluate the performance of a new artificial intelligence (AI)-driven tool for tooth detection and segmentation on panoramic radiographs., Materials and Methods: In total, 153 radiographs were collected. A dentomaxillofacial radiologist labeled and segmented each tooth, serving as the ground truth. Class-agnostic crops with one tooth resulted in 3576 training teeth. The AI-driven tool combined two deep convolutional neural networks with expert refinement. Accuracy of the system to detect and segment teeth was the primary outcome, time analysis secondary. The Kruskal-Wallis test was used to evaluate differences of performance metrics among teeth groups and different devices and chi-square test to verify associations among the amount of corrections, presence of false positive and false negative, and crown and root parts of teeth with potential AI misinterpretations., Results: The system achieved a sensitivity of 98.9% and a precision of 99.6% for tooth detection. For segmenting teeth, lower canines presented best results with the following values for intersection over union, precision, recall, F1-score, and Hausdorff distances: 95.3%, 96.9%, 98.3%, 97.5%, and 7.9, respectively. Although still above 90%, segmentation results for both upper and lower molars were somewhat lower. The method showed a clinically significant reduction of 67% of the time consumed for the manual., Conclusions: The AI tool yielded a highly accurate and fast performance for detecting and segmenting teeth, faster than the ground truth alone., Clinical Significance: An innovative clinical AI-driven tool showed a faster and more accurate performance to detect and segment teeth on panoramic radiographs compared with manual segmentation.

Purpose: To compare radiographic predictors of medication-related osteonecrosis of the jaw in dental extraction sites., Materials and Methods: Forty-one oncological patients undergoing intravenous or subcutaneous antiresorptive treatment, with a history of dental extraction visualised by panoramic imaging, were included in this retrospective study. Age-, sex- and extracted tooth-matched healthy patients who had previously undergone panoramic imaging were selected as controls (n = 57). A total of 288 extraction sites were independently evaluated by two oral and maxillofacial radiologists, who assessed eight distinct radiographic features. The radiographic features of extraction sites were noted to allow comparison between and within subjects regarding healing and osteonecrosis development. The association between radiographic findings, underlying dental disease and medication-related osteonecrosis of the jaw was also tested. The level of significance was set at 5%., Results: Patients under antiresorptive treatment presented with widening of the periodontal ligament space, thickening of the lamina dura, sclerotic bone pattern, horizontal bone loss and periapical radiolucency with bone reaction (P ≤ 0.05). Development of medication-related osteonecrosis of the jaw was associated with altered bone pattern, angular bone loss, furcation involvement and unsatisfactory endodontic treatment (P ≤ 0.05). An association between medication-related osteonecrosis of the jaw and previous dental disease was also found, particularly for periapical lesions and endodontic-periodontal disease (P ≤ 0.05)., Conclusions: Radiographic predictors of further development of medication-related osteonecrosis of the jaw in extraction sites include heterogeneous bone pattern, angular bone loss and furcation involvement. Extraction sites with underlying bony changes related to endodontic and endodontic-periodontal disease are more prone to development of medication-related osteonecrosis of the jaw., Competing Interests: The authors declare no conflicts of interest relating to this study.

The present study correlated the mineralization of third molars to chronological age using a modified classification based on Demirjian's stages in a Brazilian subpopulation and compared with the original classification. A total of 1082 patients with age ranging from 6 to 26 years were included in the sample, with at least one third molar on panoramic radiographs. The third molars were classified according to the original Demirjian classification (8 stages) and a new model based on the Demirjian method, where the original stages were grouped into four stages: AB-enamel mineralization; CD-crown dentin mineralization; EFG-root formation; and H-complete development. Statistical analyses were performed by Kruskal-Wallis/Dunn tests (α = 0.05) and the multinomial logistic regression model. Data were analyzed according to percentiles for the probability of an individual being over 18 years old. The mean ages of the stages in both classifications did not present a significant difference between superior and inferior arches (p < 0.05). The differences in mean ages between all the stages of mineralization were statistically significant (p < 0.001) only for the 4-stage classification. Males attained root formation and complete formation earlier than females (p < 0.05) in the 4-stage classification. The modified classification system showed dependence between chronological age and mineralization stages of third molars, simplifying the age estimation process. At stage H, females present a 95.7% chance of being over 18, while for males, this probability is 89.6%. This modified classification system simplifies the dental age estimation process based on third molars and can be used as a reference for future studies.

Objective: To attempt defining differential radiographic diagnostic characteristics for osteonecrotic lesions using 2D as opposed to 3D images., Materials and Methods: This was a cross-sectional study. Subjects presenting mandibular osteonecrotic lesions (osteomyelitis, osteoradionecrosis, and medication-related osteonecrosis of the jaws) were selected and compared to a group of age- and gender-matched controls, all having both cone-beam computed tomographic images (CBCT) and panoramic radiographs (PANO). Both imaging modalities (predictor variables) were evaluated by two radiologists that scored lesion presence, eight additional radiological features, and a composite severity index (outcome variables). For each pathologic condition, characteristic features were assessed in PANO and CBCT by the Wilcoxon signed-rank test. Regression tree analysis revealed the predictive value of PANO and CBCT (α = 5%)., Results: Overall, the predictive value of PANO reached 74%, while for CBCT it became 90%. Regarding the composite severity index, CBCT enabled to detect more subtle lesions. Also, CBCT imaging allowed showing more distinct radiographic diagnostic features as compared to PANO imaging, more specifically when distinguishing osteomyelitis from both other lesions., Conclusions: Cone-beam computed tomography enabled showing more differences in radiological features between distinct osteonecrosis disease entities. CBCT imaging might be a better contributor for the detection of early lesions and to monitor further pathological developments in the mandible., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.)

Objective: The aim of this study was to evaluate the influence of image enhancement filters on detection of fractured endodontic instruments and on image noise and pixel intensity., Study Design: In total, 26 mandibular molars (68 root canals), divided into 4 groups (presence/absence of root canal filling, and presence/absence of a fractured endodontic instrument) were radiographed by using a complementary metal oxide semiconductor (CMOS) and a photostimulable phosphor (PSP) system. Images with 4 enhancement filters (Sharpen UM, Edges All, BC Low, and BC High) were compared with nonfiltered images. The area under the receiver operating characteristic curve (Az), sensitivity, and specificity in detection of fractured instruments were compared for each imaging condition. Means and standard deviations (SD) to measure noise and changes in pixel intensity were calculated. Analysis of variance was used to analyze the data., Results: There were no significant differences in Az, sensitivity, and specificity values between nonfiltered and filtered images in detection of instruments in root canals without and with root canal filling (P ≥ .360). SD was reduced by filters in CMOS but not PSP radiographs. Sharpen UM caused more changes in the mean values in both systems., Conclusions: Filters did not improve diagnostic performance in detecting instruments. Noise and pixel intensity were affected differently., (Copyright © 2020 Elsevier Inc. All rights reserved.)