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Objective: The aim of this study was to evaluate the accuracy of multislice computed tomography (MSCT) and cone beam computed tomography (CBCT) scanners in the assessment of trabecular bone microarchitecture by radiomorphometric analysis., Methods: Eight dry human hemimandibles were selected and scanned by 4- and 128-MSCT, CBCT with different voxel sizes, and a computed microtomography (micro-CT). The images were spatially aligned, the axial slices were segmented using CTAn software (Skyscan, Konitch, Belgium), and 10 bone morphometric parameters were quantified. The micro-CT images were the criterion standard., Results: The results show the superiority of CBCT images with 0.2-mm voxel size and 128-MSCT., Conclusions: We can conclude that the CBCT scanner with 0.2-mm voxel size and 128-MSCT had better performance on reproducibility of the distribution and organization of trabecular bone and marrow spaces evaluated in this study., Competing Interests: The authors declare no conflict of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Sickle-cell disease (SCD), which involves morphological changes to the red blood cells, is the most common hemoglobinopathy worldwide. This conformational change in erythrocytes affects multiple organs and systems, including the hard and soft tissues of the stomatognathic system. The objective of this study was to provide a description of the maxillomandibular positioning of patients using computed tomography in a case series of 40 patients with SCD. To define the facial profile of patients, 2-dimensional (2D) and 3-dimensional (3D) McNamara and Steiner cephalometric tracings were performed. The results showed that there is a tendency to maxillary protrusion in 2D and 3D analyses. There was no statistical difference between the 2D and 3D evaluations; additionally, sex affected the maxillomandibular positioning of patients, but only in McNamara evaluations.

Osteomas are benign osteogenic lesions that result from the proliferation of mature bone. Three variants are known: central, peripheral, and extraskeletal. The peripheral variant is the most common and it most frequently affects the paranasal sinuses, rarely occurring in the jaws. This article describes the case of a 33-year-old white male patient who was referred complaining of facial asymmetry. Clinical examination revealed an increase in volume at the base of the right side of the mandible, hard bony consistency and well delimited, painless to the touch, without signs of infection or intraoral alterations. Radiographic examination revealed an oval lobulated, radiopaque sessile lesion adhered to the mandibular base near the insertion of the masseter muscle. The patient reported practicing martial arts many years ago. Owing to the limited access, it was decided to perform the complete lesion removal through an extraoral surgical approach, by using a skin crease in the upper neck region below the lesion. The patient recovered well and the histopathological analysis confirmed the diagnosis of osteoma. The etiopathogenesis of osteoma is not completely elucidated, and 3 theories are more accepted: developmental defect, neoplastic nature, and reactive lesion owing to trauma or local infection. The clinicopathological correlation in the present case supports a traumatic origin. Traumatic peripheral osteoma should be considered in the differential diagnosis of nodular bone-forming lesions affecting the mandible.

Age and sex estimation is crucial in forensic investigations, whether in legal situations that involve living people or to identify mortal remains. The aim of this study was to establish reference values in a Brazilian population to estimate age and sex by measuring the length of the mandibular ramus on lateral cephalometric radiographs, and to determine the probability that an individual being is 18 years or older, based on the results that were obtained. Two hundred and eighteen scanned lateral cephalograms of individuals between 6 and 20 years of age (101 males and 117 females) were measured with reference to mandibular ramus length (the distance between Condylion superior (Cs) and Gonion (Go)) using ImageJ 1.41 software (NIH, Bethesda, MA, USA). The results showed that sexual dimorphism was not observed until 16 years and, based on the ramus length measurements in this sample, it is possible to predict sex with an accuracy of only 54 %. There was a positive correlation between age and ramus length (r = 0.90; p < 0.001). From the linear regression analysis, one formula was derived; therefore, it was possible to calculate the individual's age, given his or her ramus length. The results showed that if an individual's ramus length is 7.0 cm or more, then there is an 81.25 % chance that the individual is 18 years old or older. In conclusion, the mandibular ramus length was not effective in discriminating sex. Mandibular length is strongly related to chronological age and can be used to predict whether an individual is 18 years or older with high degree of expected accuracy.

Objectives: The aim of this study was to evaluate the accuracy of virtual three-dimensional (3D) reconstructions of human dry mandibles, produced from two segmentation protocols ("outline only" and "all-boundary lines")., Materials and Methods: Twenty virtual three-dimensional (3D) images were built from computed tomography exam (CT) of 10 dry mandibles, in which linear measurements between anatomical landmarks were obtained and compared to an error probability of 5 %., Results: The results showed no statistically significant difference among the dry mandibles and the virtual 3D reconstructions produced from segmentation protocols tested (p = 0,24)., Conclusions: During the designing of a virtual 3D reconstruction, both "outline only" and "all-boundary lines" segmentation protocols can be used., Clinical Relevance: Virtual processing of CT images is the most complex stage during the manufacture of the biomodel. Establishing a better protocol during this phase allows the construction of a biomodel with characteristics that are closer to the original anatomical structures. This is essential to ensure a correct preoperative planning and a suitable treatment.

Objective: The aim of this study was to investigate whether some mandibular measurements on panoramic radiographs are associated with low bone mineral density in postmenopausal women., Methods: A sample of 122 panoramic dental radiographs and bone density tests from women 50 years or older were examined. Bone mineral density was measured in the lumbar spine and proximal femur regions through dual-energy x-ray absorptiometry. The mandibular cortical bone thickness below the mental foramen, mandibular alveolar bone resorption, and panoramic mandibular index were measured., Results: The mandibular cortical thickness and mandibular alveolar bone resorption showed the highest specificity (lumbar spine: 89.8% vs 73.5%, proximal femur: 83.6% vs 71.2%, respectively). The panoramic mandibular index demonstrated the highest sensitivity (lumbar spine: 43.8%; proximal femur: 40.8%). The association between the mandibular cortical thickness and bone mineral density was statistically significant even after adjustment for hormonal treatment, smoking, age at menopause, and body mass index (P = 0.04)., Conclusions: It is suggested that panoramic radiography may be useful for confirming individuals who present with low bone mineral density.