Jefferson Xavier de Oliveira

Computed tomography imaging findings of simultaneous bifid mandibular condyle and temporomandibular joint ankylosis: case report

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.

Correlation among the changes observed in temporomandibular joint internal derangements assessed by magnetic resonance in symptomatic patients.

PURPOSE The objective was to assess possible correlations among the anatomy and position of the articular disc, the morphology of the articular eminence and of the condyle, and the presence of joint effusion. MATERIALS AND METHODS Magnetic resonance images of 142 joints of symptomatic patients were assessed. The articular disc was classified as normal, elongated, or folded; displacement was classified as normal, anterior with reduction, anterior without reduction, or posterior, lateral, or medial; the condyle was classified as rounded, convex, flattened, or angulated; and the articular eminence was classified as box, sigmoid, flattened, or deformed. RESULTS The most frequent forms of the articular disc, articular eminence, and condyle were normal, box, and flattened, respectively. Associations were confirmed between the form of the articular disc and its anterior and lateral positions; between the form of the condyle and an anterior position of the disc; and between the form of the articular eminence and the form of the disc. The form of the articular eminence was the only variant that was not associated to the presence of joint effusion. CONCLUSIONS Magnetic resonance imaging allowed the clear observation of articular structures, without attributing a cause-and-effect relation. The prevalence of changes observed was associated with the diagnosis of internal derangement and was statistically proved.

Assessment of osteoporotic alterations in achondroplastic patients: a case series

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.

Assessing joint effusion and bone changes of the head of the mandible in MR images of symptomatic patients

The aim of the present study was to investigate the relationship between degenerative bone changes of the head of the mandible and the presence of joint effusion (JE). This study was based on sagittal magnetic resonance imaging (MRI) reports of 148 temporomandibular joints (TMJs) of 74 patients complaining of pain and/or dysfunction in the TMJ area. The mandible heads were surveyed for osteoarthritis characteristics, which were classified as osteophytosis, sclerosis or erosion. The presence of JE was checked whenever high signal intensity was observed in the articular space. The results evidenced the presence of bone changes in 30% of the sample. Osteophytes and erosions were the changes most commonly observed. JE was reported in 10% of TMJs. The results from the statistical tests revealed that bone changes in the head of the mandible are associated with the presence of JE.

Odontoameloblastoma: report of two cases.

Odontoameloblastoma (OA) is a very rare mixed odontogenic neoplasm, characterized by the simultaneous occurrence of an ameloblastoma and a compound or complex odontoma in the same tumor mass. To date, less than 50 cases of OA and/or ameloblastic odontoma have been reported in the English dental literature. This neoplasm was called ameloblastic odontoma. The term OA was included in the 1971 WHO classification. In this study, we present two cases of OA, which we hope will contribute to the awareness and knowledge of surgeons regarding the existence of this odontogenic tumor so that patients having it may be treated and followed-up properly.

Strontium Ranelate Effect on the Repair of Bone Defects and Molecular Components of the Cortical Bone of Rats

This study was conducted to evaluate the effects of treatment with strontium ranelate (SR) on the repair of bone defects and molecular components of bones in femurs. Adult female rats (n=27) were subjected to ovariectomy (OVX) or Sham surgery. Thirty days after surgery, a defect was made in the femur and the animals were then divided into three groups: OVX, SHAM and OVX+SR. Euthanasia was performed four weeks after the bone defect surgery. Repair in bone defect was assessed by computed microtomography (μCT) and chemical composition of cortical bone was analyzed by Fourier transform infrared (FTIR) spectroscopy and energy dispersive X-ray spectroscopy (EDS). The trabecular thickness (Tb.Th) of the newly formed bone in the OVX+SR group was significantly higher than that for the OVX group. The collagen maturity in the OVX+SR group was smaller than in the other two groups. In this group, a significant increase in the amount of strontium (Sr) and a decrease in the amount of calcium (Ca) embedded to bone tissue were also observed. Systemic treatment with SR improved microarchitecture of the newly formed bone inside the defect, but decreased cross-linking of mature collagen in cortical bone.

Computed tomography imaging strategies and perspectives in orbital fractures

Objective: The objective of this study was to demonstrate the sensitivity and specificity of multislice computed tomography (CT) for diagnosis of orbital fractures following different protocols, using an independent workstation. Materials and methods: CT images of 36 patients with maxillofacial fractures (symptomatic to orbit region) who were submitted to multislice CT scanning were analyzed, retrospectively. The images were interpreted based on 5 protocols, using an independent workstation: 1) axial (original images); 2) multiplanar reconstruction (MPR); 3) 3D images; 4) association of axial/MPR/3D images and 5) coronal images. The evaluated anatomical sites were divided according to the orbital walls: lateral (with or without zygomatic frontal process fracture); medial; superior (roof) and inferior (anterior, medial). The collected data were analyzed statistically using a validity test (Youdens J index; p<0.05). The clinical and/or surgical findings (medical records) were considered as the gold standard to corroborate the diagnosis of the anatomical localization of the orbital fracture. Results: 3D-CT scanning presented sensitivity of 78.9%, which was not superior to that of MPR (84.0%), axial/MPR/3D (90.5%) and coronal images (86.1%). On the other hand, the diagnostic value of axial images was considered limited for orbital fractures region, with sensitivity of 44.2%. Conclusions: Except for the axial images, which presented a low sensitivity, all methods evaluated in this study showed high specificity and sensitivity for the diagnosis of orbital fractures according to the proposed methodology. This protocol can add valuable information to the diagnosis of fractures using the association of axial/MPR/3D with multislice CT.

Fibrous Dysplasia Characterization Using Lacunarity Analysis.

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.

Analysis of the cephalometric pattern of Brazilian achondroplastic adult subjects

OBJECTIVE: The aim of this study was to assess the position of the cranial base, maxilla, and mandible of Brazilian achondroplastic adult subjects through cephalometric measurements of the cranio-dento-facial complex, and to compare the results to normal patterns established in literature. METHODS: Fourteen achondroplastic adult subjects were evaluated based on their radiographic cephalometric measurements, which were obtained using the tracings proposed by Downs, Steinner, Bjork, Ricketts and McNamara. Statistical comparison of the means was performed with Students t test. RESULTS: When compared to normal patterns, the cranial base presented a smaller size in both its anterior and posterior portions, the cranial base angle was acute and there was an anterior projection of the porion; the maxilla was found to be smaller in size in both the anteroposterior and transversal directions, it was inclined anteriorly with anterior vertical excess, and retropositioned in relation to the cranial base and to the mandible; the mandible presented a normal-sized ramus, a decreased body and transverse dimension, a tendency towards vertical growth and clockwise rotation, and it was slightly protruded in relation to the cranial base and maxilla. CONCLUSION: Although we observed wide individual variation in some parameters, it was possible to identify significant differences responsible for the phenotypical characteristics of achondroplastic patients.

Prevalence of soft tissue calcifications in cone beam computed tomography images of the mandible

PURPOSE: To determine the prevalence of soft tissue calcifications in the mandible in cone beam computed tomography (CBCT) scans. METHODS: The sample was composed by 246 CBCT scans of the mandible; 163 were acquired by the NewTom 3G® system, and 83 were acquired by the Classic i-Cat® system. When the presence of soft tissue calcification was confirmed in the mandible, the anatomical location and the type of calcification (single or multiple) were determined. Elongated styloid process and ossification of the stylohyoid ligament were excluded. Data were analyzed by using Fishers exact test and chi-square tests. RESULTS: A total of 37 out of 246 scans showed soft tissue calcifications in the mandible (prevalence of 15%). Soft tissue calcification is predominant at posterior region of the mandible (18.9%), with no relation to gender and age. From the total of patients with soft tissue calcification, 73% were aged 35-55 year-old. There was no significant difference of diagnostic quality of the images between the CBCT systems (P > 0.05). CONCLUSION: The prevalence of soft tissue calcifications was high in this sample using CBCT images for diagnosis in the mandibular region.