Purpose: This study aimed to compare the diagnostic performance of cone-beam computed tomography (CBCT) and digital periapical radiography in detecting separated endodontic instruments (SI) according to their type and length infilled root canals of mandibular molars. Materials and Methods: Forty-two extracted mandibular molars were divided into 2 groups: control (without SI) and experimental (with SI). In the experimental group, SI fragments (2 or 3 mm) from 3 endodontic instruments (WaveOne Gold, Reciproc Blue, and ProTaper Next) were inserted into the mesiobuccal canals of 30 teeth. CBCT scans were obtained using the KAVO OP 3D PRO device, and digital periapical radiographs (orthoradial, distal, and mesial) were acquired using the Focus X-ray unit with the RVG 5200 solid sensor. Three experts independently evaluated all images for SI detection using a 5-point scale. Diagnostic performance metrics were calculated for each imaging method, andcomparisons were performed using 1-way analysis of variance with Tukey post-hoc tests. The significance level wasset at 5% (P = 0.05). Results: Digital periapical radiography demonstrated higher area under the receiver operating characteristic curve (Az), sensitivity, and specificity values than CBCT. ProTaper Next SI on CBCT scans showed the lowest Az values (0.58and 0.56 for 2- and 3-mm fragments, respectively). These values were significantly different from those of the other SIconditions (both CBCT and digital periapical radiography) (P<0.05). Conclusion Digital periapical radiography outperformed CBCT in detecting SI in filled root canals of mandibularmolars and should be the preferred modality. Furthermore, SI detectability varies with imaging modality, depending on instrument type and fragment length.

Purpose: This study assessed the intensity of artifacts produced by 2 metal posts, 2 cements, and different exposure parameters using 2 cone-beam computed tomography (CBCT) units. Materials and Methods: The sample was composed of 20 single-rooted premolars, divided into 4 groups: Ni-Cr/ zinc phosphate, Ni-Cr/resin cement, Ag-Pd/zinc phosphate, and Ag-Pd/resin cement. Samples were scanned before and after post insertion and cementation using a CS9000 3D scanner with 4 exposure parameters (85/90 kV and 6.3/10 mA) and an i-CAT scanner with 120 kV and 5 mA. The presence of artifacts was assessed subjectively by 2 observers and objectively by a trained observer using ImageJ software. The Mann-Whitney, Wilcoxon, weighted kappa, and chi-square tests were used to assess data at a 95% confidence level (α<0.05). Results: In the subjective analyses, AgPd presented more hypodense and hyperdense lines than NiCr (P<0.05), and more hypodense halos were found using i-CAT (P<0.05) than using CS9000 3D. More hypodense halos, hypodense lines, and hyperdense lines were observed at 10 mA than at 6.3 mA (P<0.05). More hypodense halos were observed at 85 kV than at 90 kV (P<0.05). CS9000 3D presented more hypodense and hyperdense lines than i-CAT (P<0.05). In the objective analyses, AgPd presented higher percentages of hyperdense and hypodense artifacts than NiCr (P<0.05). Zinc phosphate cement presented higher hyperdense artifact percentages on CS9000 3D scans (P<0.05). CS9000 3D presented higher artifact percentages than i-CAT (P<0.05). Conclusion High-atomic-number alloys, higher tube current, and lower tube voltage may increase the artifacts present in CBCT images. (Imaging Sci Dent 2023; 53: 127-35)

Objective: To identify optimal areas for the insertion of extra-alveolar miniscrews into the infrazygomatic crest (IZC) and mandibular buccal shelf (MBS), using cone beam computed tomography (CBCT) imaging in patients with different craniofacial patterns. Methods: CBCT reconstructions of untreated individuals were used to evaluate the IZC and MBS areas. The participants were divided into three groups, based on the craniofacial pattern, namely, brachyfacial (n = 15; mean age, 23.3 years), mesofacial (n = 15; mean age, 19.24 years), and dolichofacial (n = 15; mean age, 17.79 years). In the IZC, the evaluated areas were at 11, 13, and 15 mm above the buccal cusp tips of the right and left first molars. In the MBS, the evaluated areas were at the projections of the first molars’ distal roots and second molars’ mesial and distal roots, at a 4- and 8-mm distance from the cementoenamel junction. Intergroup comparisons were performed with analysis of variance and the Tukey test. Results: There was no statistically significant difference in the IZC bone thickness among the groups. For MBS bone availability, some comparisons revealed no difference; meanwhile, other comparisons revealed increased MBS bone thickness in the brachyfacial (first molars distal roots) and dolichofacial (second molars mesial and distal roots) patterns. Conclusions There was no significant difference in the IZC bone thickness among the groups. The facial skeletal pattern may affect the availability of ideal bone thickness for the insertion of extra-alveolar miniscrews in the MBS region; however, this variability is unlikely to be clinically meaningful.

Purpose: The purpose of this study was to use cone-beam computed tomography (CBCT) images to determine the prevalence of calcifications in the temporomandibular joint (TMJ) and to evaluate any associations between the presence of such calcifications and degenerative bone alterations of the TMJ, sex, or age. Materials and Methods: In this retrospective study, 1,058 CBCT exams were analyzed, and data regarding the presence and quantity of calcifications, the affected side, any degenerative alterations of the condyle, sex, and age were collected. To evaluate associations between the presence of calcifications and sex or age, the Fisher exact test or the Spearman correlation coefficient, respectively, was used. To assess the association between the presence of calcifications and joint bone alterations, the chi-square and Fisher exact tests were used. The significance level adopted was 5% (p<0.05). Results: Twenty-eight patients (2.7%) presented with TMJ calcifications, including 23 women (82.1%) and 5 men (17.9%). Significant correlations were found between the presence of calcifications and age (p<0.05) and between the presence of calcifications and the presence of condylar alterations (p<0.05), with 73.2% of patients with bone alterations having TMJ calcifications. Conclusion It may be concluded that, although rare (with a prevalence of only 2.7%), intra-articular calcifications are associated with both degenerative bone alterations and age.