The aim of this study was to assess the shape of the temporomandibular joint (TMJ) articular eminence and the articular disc configuration and position in patients with disc displacement. TMJ magnetic resonance images (MRI) of 14 patients with bilateral disc displacement without unilateral reduction were analyzed. Articular eminence morphology was characterized as box, sigmoid, flattened, or deformed. Articular disc configuration was divided into biconcave, biplanar, biconvex, hemiconvex or folded, and its position, as "a" (superior), "b" (anterosuperior), "c" (anterior) or "d" (anteroinferior). The images were divided and the sides with disc displacement with reduction (DDWR) and without reduction (DDWOR) were compared. Regarding articular eminence shape, the sigmoid form presented the greatest incidence, followed by the box form, in the DDWR side, although this was not statistically significant. In the DDWOR side, the flattened shape was the most frequent (p = 0.041). As to disc configuration, the biconcave shape was found in 79% of the DDWR cases (p = 0.001) and the folded type predominated in 43% of the DDWOR cases (p = 0.008). As to disc position, in the DDWR side, "b" (anterosuperior position) was the most frequent (p = 0.001), whereas in the DDWOR side, "d" (anteroinferior position) was the most often observed (p = 0.001). The side of the patient with altered disc configuration and smaller shape of TMJ articular eminence seems to be more likely to develop non-reducing disc displacement as compared to the contralateral side.

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Achondroplasia (ACH) is the most common form of human dwarfism and has been associated with biochemical alterations of the bone tissue, also observed in cases of osteoporosis. The present case series aimed at assessing low bone density, diagnosed with spinal bone mineral density (BMD) analysis and with panoramic radiograph measurements, in ACH patients. Spinal BMD was measured by means of dual-energy X-ray absorptiometry at the lumbar region (L1-L4). On dental panoramic radiographs of the patients, the mandibular cortical width was measured separately on the right and left sides. The Klemetti Index was also assigned as appropriate for evaluating the cortical area below the mandibular foramen. Additional parameters such as patient age, gender, body mass index, and number of teeth were also recorded. BMD results showed that 5/11 cases presented with skeletal osteopenia/osteoporosis diagnoses. Additionally, mandibular cortical erosion was detected in panoramic radiographs in 8/11 cases. The BMD and panoramic radiographic alterations found in this study suggest that the diagnosis of low bone density may have a special clinical relevance in cases of bone tissue disorders, such as achondroplasia.

Bifid mandibular condyle is an uncommon entity described in the literature as having a controversial etiology. Despite the absence of clinical symptomatology, the radiologist must be aware and should have some knowledge of this abnormality, as well its implications regarding functional and morphological changes. TMJ ankylosis is a disabling disease with involvement of the mandibular condyle, articular fossa and base of the skull. The association of bifid condyle with temporomandibular joint ankylosis is rare and must be carefully evaluated. The purpose of this paper is to report a case of simultaneous bifid mandibular condyle and temporomandibular joint ankylosis and to describe its computed tomography imaging findings.

Objectives: The aim of this study was to investigate bone changes in the condyle, articular eminence and glenoid fossa in relation to the position of the articular disc. Methods: 148 temporomandibular joints (TMJs) of 74 symptomatic patients who underwent MRI were evaluated. The position of the disc was classified as either normal (N), disc displacement with reduction (DDwR), disc displacement without reduction (DDwoR) and posterior displacement (PD). Bone changes were investigated in the condyle and temporal components of the TMJ and classified as osteophytosis, sclerosis or erosion. Results: There were no bone changes in the glenoid fossa of the temporal bone. Of the total number of TMJs studied, 94 (63.5%) were N, 34 (23%) presented DDwoR, 19 (12.8%) presented DDwR and 1 (0.7%) presented PD. The bone changes in the condyle and posterior aspect of the articular eminence were associated with the position of the disc. The bone changes in the anterior aspect of the articular eminence were not associated with the position of the disc. Conclusion: In cases of DDwoR, bone changes in the condyles were more common. The combination of erosion and osteophytosis in the condyle and the bone changes of the posterior aspect of the articular eminence were associated with disc position.

Fibrous dysplasia (FD) is a developmental anomaly in which the normal medullary space of the affected bone is replaced by fibro-osseous tissue. This condition is typically encountered in adolescents and young adults. It affects the maxillofacial region and it can often cause severe deformity and asymmetry. Therefore, accurate diagnosis is critical to determine the appropriate treatment of each case. In this sense, computed tomography (CT) is a relevant resource among the imaging techniques for correct diagnosis of this condition. Thus, in this paper, we propose to analyze fibrous dysplasia through its texture pattern. To accomplish this task, we propose to use lacunarity analysis, a multiscale method for describing patterns of spatial dispersion. Results indicated lower lacunarity values for fibrous dysplasia in comparison to normal bone samples, an indication that their texture images are more homogeneous, and a high separability between the classes when using principal component analysis (PCA) and decision trees for statistical analysis.

The detection of osteomas in the maxillofacial region may be the initial clinical finding in Gardner's syndrome (GS). The most common location of osteomas is in the skull, but the lesion can also occur in the jaws. We present a case of a 47 year old male patient with GS who was referred for radiological evaluation. Extraoral examination revealed an epidermoid cyst and the patient had a history of intestinal polyps. A panoramic radiograph demonstrated numerous osteomas and diffuse sclerosis of the mandible, and compound odontomas with impacted teeth. CT scan allowed the localization and extension of the osteomas, and showed other sites in the maxillofacial region as well. CT images also revealed a different behaviour of osteoma, invading the mandibular canal.

A rare case of aplasia of the mandibular condyle is presented along with the tomographic findings. A 31-year-old Caucasian woman presented with a main complaint of facial asymmetry. No family history or any trauma was found. A CT study was performed and the sagittal CT view demonstrated a complete absence of the left condyle. This case of unknown aetiology was thoroughly examined and, based on clinical findings, we suggest that it could be of developmental origin.