Nádia Assein Arús

Central Cemento-Ossifying Fibroma: Clinical Imaging and Histopathological Diagnosis

Central ossifying fibroma is a lesion in which diagnosis has proved intriguing and unclear for presenting clinical, radiographic, and even histopathological similarities to other types of lesions such as the fibrous dysplasia of bone and cement-bone dysplasia. It is a benign neoplasm of uncertain etiology and slow development in which the mandible is affected more frequently than the maxilla. We described a case of central cemento-ossifying fibroma involving the right mandible of a thirty-five-female patient by presenting its clinical, radiographic, and histological characteristic sand discussing some differential diagnoses.

Airway volume analysis: is there a correlation between two and three-dimensions?

Objectives No consensus exists on the assessment of airway in CBCT scans. Two-dimensional measures remain the standard in the cephalometric analysis. This research aimed to evaluate linear and area measurements in two-dimensional views from specific airway regions of interest and compare these to the correspondent volume in CBCT exams. Materials and Methods 250-selected CBCT scans were retrospectively analyzed. A trained and calibrated examiner performed the linear, area and volume measurements in specific sites for nasal cavity, nasopharynx and oropharynx compartments. Dolphin Software was used for the analysis. The correlations were performed using Pearson coefficient. Results The highest positive correlations were observed in the nasopharynx and oropharynx sagittal areas and the most constricted area in the oropharynx. Nasopharynx linear measures and nasopharynx coronal area did not present correlation with whole volume. Two-dimensional measurements in the soft palate (width and sagittal area) showed very low positive correlations. Although nasal cavity presented highest volume means, changes in oropharynx contributed more to variations in total volume, compared with the other two sections. Conclusion Airway sagittal areas, as well as the most constricted axial area in oropharynx remains a useful guide to correlate with airway volume in two-dimensional images.

Is cone beam computed tomography accurate for postoperative evaluation of implants? An in vitro study

OBJECTIVE The aim of this study was to evaluate the accuracy of cone beam computed tomography (CBCT) for evaluation of the bone-implant interface in comparison with periapical radiography. STUDY DESIGN Titanium implants were inserted in 74 bovine rib blocks in intimate contact with bone walls and with a gap of 0.125 mm (simulating failure in the osseointegration process). Periapical radiographs were taken with conventional film, and CBCT scans were acquired with i-CAT (0.2 mm and 0.125 mm voxel) and Kodak (0.2 mm and 0.076 mm voxel) units. Three examiners evaluated the images using a 5-point scale. Diagnostic accuracy was analyzed through sensitivity, specificity, and the area under the receiver operating characteristic (ROC) curve (AUC) with 95% confidence intervals (CIs). Intra- and interexaminer agreements were analyzed through Kendalls concordance test. RESULTS Intra- and interexaminer agreements showed satisfactory results. The greatest accuracy was observed with conventional radiography (AUC = 0.963; CI 95% = 0.891-0.993). I-CAT 0.125-mm images showed good accuracy (AUC = 0.885; CI 95% = 0.790-0.947), with no significant difference compared with conventional radiography. Kodak images had high specificity and low sensitivity, presenting more false-negative results. CONCLUSIONS Conventional radiography showed the highest accuracy for assessment of the bone-implant interface. However, CBCT (i-CAT; 0.125-mm voxel), if available or if performed for preoperative assessment of another implant site, may provide similar accuracy.

Development and evaluation of an extraoral radiographic simulator model

Objectives: To describe the development of an extraoral radiographic simulator model that allows the demonstrations of head position and practical training of extraoral radiographic techniques and its usability evaluation by the users. Methods: It was used a macerated human skull, autopolymerising acrylic resin, orthodontic elastics, screws, polyvinyl chloride pipe and a photograph tripod to build it. After theoretical and demonstration classes, and practical training using the simulator model, twenty-nine professionals from the last five classes of an Oral Radiology Specialization Course filled out a form to evaluate its usability. Results: the modified SUS (System Usability Scale) final score obtained for usability was eighty-three, indicating high acceptance of the simulator model. Conclusion: this extraoral radiographic simulator model can be built at a very low cost, is useful for practice extraoral radiographic techniques and it should be encouraging its use as a teaching aid in other institutions. Correspondence to: Heraldo Luis Dias da Silveira, Dental School – Federal University of Rio Grande do Sul, Oral Radiology Division, Rua Ramiro Barcelos, 2492/5 floor, Porto Alegre, RS – Brazil, Tel: 55–51–33085199, E-mail: heraldo@ufrgs.br

The presence of calcifications along the course of internal carotid artery in Greek and Brazilian populations: a comparative and retrospective cone beam CT data analysis.

OBJECTIVES We aimed to retrospectively compare the prevalence of soft tissue calcifications (STCs) depicted incidentally along the extra- and intracranial course of the internal carotid artery (ICA) on cone beam computed tomography examinations in 2 different populations (Greeks and Brazilians). METHODS The cohort consisted of examinations of 232 Greeks and 174 Brazilians, for a total of 406 patients. The scans were evaluated for the presence of STCs along the course of the ICA, with data analyzed in each ethnic group according to gender and age criteria. RESULTS In total, 355 STCs were recorded; 78 (22.0% of all STCs) and 58 (16.3%) were extracranials, and 128 (36.1%) and 91 (25.6%) were intracranials for Greeks and Brazilians, respectively. The χ(2) test indicated no statistical differences between Greeks and Brazilians in the occurrence of STCs; however, their prevalence differed between genders in those populations. The presence of lesions, both extra- and intracranially, was found to increase with age (P < .05). The odds ratios were estimated at 2.23 (95% CI, 1.81-2.74) and 3.26 (95% CI, 2.56-4.16) for extracranial and intracranial lesions, respectively, with increasing age. CONCLUSIONS We found an equal distribution for both extra- and intracranial STCs among Greeks and Brazilians. The prevalence of lesions differed between genders within both populations. Aging was found to be a risk factor for STCs, as the odds ratio increased significantly.

Diagnostic reproducibility of the second mesiobuccal canal by CBCT: influence of potential factors

ObjectivesThe use of cone-beam computed tomography (CBCT) in endodontics includes the assessment of endodontic pathologies, presurgical planning, and canal morphology. The performance of CBCT scans to observe pathologic conditions and anatomic structures in three-dimensional reconstructions has proven to be incredibly useful. The quality of the images, the conditions for their analysis, and the operator’s skill and care during the image acquisition strongly affect the incidence of diagnostic errors. In the same way, the validity of any test for diagnosis depends on its reliability. The purpose of this study was to assess the ability of three observers to accurately confirm the existence and absence of MB2 canals in human first upper molars with different root conditions.MethodsThree trained and calibrated dentists from a postgraduate program on oral and maxillofacial radiology were asked to identify MB2 canals in 82 extracted human first upper molars under different conditions depending on the MB1 root canal (non-filled, filled, and deobturated). Kappa values among the observers were obtained.ResultsThe agreement among the examiners ranged from 0.39 to 0.68. The kappa values were more impaired by the root condition than by the voxel size. Moreover, experience in CBCT image evaluation played a role in agreement among the examiners.ConclusionsThe results suggest that root condition and professional experience have more influence for agreement during MB2 diagnosis than voxel size.