A survey of radiographic prescription in dental implant assessment

Objectives: To survey the current radiographic prescriptions in dental implant assessment amongst dentists in Brazil.Methods: Sixty-nine dentists were interviewed during a dental implant meeting by two calibrated graduate students, using a 19-question questionnaire, considering imaging modality options both for pre-operative implant site assessment and for follow-up, particularly with respect to cost, patient radiation dose, and broad coverage of facial bones and teeth. Epi-Info 6.04 software was used to analyse the database file.Results: Approximately 63.8% of the dentists prescribed only panoramic radiography for dental implant assessment and 28.9% ordered panoramic radiography plus periapical radiography and/or conventional tomography and/or computed tomography (CT). Only 7.2% of the dentists ordered conventional tomography or CT as a single examination, although 10.1% ordered it in combination with other imaging modalities. The main reasons given for prescribing panoramic radiography were broad coverage and cost (86.4%).Conclusions: This study has shown that most of the dentists in this study prescribe panoramic radiographs in dental implant assessment based on broad coverage and cost. They are not following the American Academy of Oral and Maxillofacial Radiology recommendations regarding cross-sectional imaging.

Tests of one Brazilian facial reconstruction method using three soft tissue depth sets and familiar assessors

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Malignant ameloblastoma metastasis to the lung: a case report

Ameloblastoma is an odontogenic tumor, usually benign, which rarely metastasizes to distant organs. The case of a 27-year-old white woman is described, who presented a metastatic pulmonary ameloblastoma 7 years after the removal of a mandibular ameloblastoma. She presented no pulmonary symptoms, but a lung nodule was found in a chest x-ray during a routine check-up for job admission. Computed tomography (CT) revealed a 2-cm well-defined solitary round nodule without calcifications, leading to the hypothesis of a metastatic tumor. Clinical and CT investigation confirmed no ameloblastoma recurrence in the jaw and no other primary tumor. The diagnosis of metastatic ameloblastoma was confirmed by microscopic evaluation of the pulmonary nodule.

Aggressive management of orbital meningeal melanocytoma

Objective. Meningeal melanocytoma generally occurs in the posterior fossa. Orbital manifestation is rarely encountered.Methods. A thirty-five year-old man presented with progressive proptosis of his right eye. Computed tomography (CT) and Magnetic Resonance Imaging (MRI) of the brain showed an expansive intraconal mass lesion occupying the superior orbital compartment, the entire orbital apex, and the optic foramen. Histological analysis and Immunohistochical staining for S-100 and HMB-45 monoclonal antibodies confirmed melanocytoma.Findings. Microsurgical removal was accomplished through a fronto-orbital craniotomy. Chemotherapy and irradiation followed the initial intervention. The patient returned for follow up two years after surgery, complaining of headache and right visual loss. A subfrontal tumor with massive edema was found on follow up CT scan.Interpretation. Meningeal melanocytomas are rare benign pigmented tumors of the central nervous system. They are predominant in the posterior fossa and spinal cord and frequently mistaken for melanomas, especially on frozen sections. Orbital presentation is rare. The natural history is poorly defined.

Association of 3D Reconstruction and Conventional Radiography for the Description of the Appendicular Skeleton of Chelonoidis carbonaria (Spix, 1824)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo comparativo dos métodos de ultra-sonografia, tomografia computadorizada e ressonância magnética no estadiamento e invasão das estruturas adjacentes por tumores renais.

BACKGROUND: Ultrasonography (US), Computed Tomography (CT), and Magnetic Resonance imaging (MR) were compared for the staging of renal tumors. The differences between these imaging techniques were also studied for their ability to detect adenopathies, vascular invasion, distant intra-abdominal metastases, and particularly adjacent organ invasion. METHODS: Thirty-one patients with solid or complex renal masses were prospectively studied using US, CT, and MR. Differences between the results obtained were studied using the COCHRAN G test and the McNEMAR test. The sensitivity and specificity of each diagnostic technique were compared against a gold standard of the surgical and histopathological findings. RESULTS: The following sensitivities were obtained: For the detection of adenopathy, US 63.6%, CT and MR 90.9%. For vascular invasion, US 42.8%, CT and MR 85.7%. For the adjacent organ invasion, US 28.5%, CT 85.7%, and MR 71.4%. Some of the criteria that suggest invasion of adjacent structures include: the envelopment of the adjacent structures by the tumor, tumor extension into the adjacent structures with an irregular appearance, and alterations in shape, size, and density of adjacent structures. Loss of fat planes between the tumor and adjacent structures is not a sign of tumor invasion. CONCLUSIONS: Significant differences were found in the detection capacity of US in relation to CT and MR, which were similar. All three techniques were highly sensitive and specific only in the detection of distant abdominal metastases. In addition to the accuracy of these diagnostic modalities for the detection and staging of tumors, invasiveness, risks and cost should be considered in relation to relative costs and benefits.

Avaliação da inclinação do incisivo inferior através da tomografia computadorizada

Introduction: Orthodontics has always used lateral cephalometric radiographs (LC) as the main examination in the orthodontic diagnosis and treatment plan. The determination of incisor position is part of most cephalometric analysis, including Tweed analysis. However, all radiographic images have limitations, since it is a bidimensional image of a tridimensional structure and overlapping of bone and dental structures often occurs. Computed tomography (CT) allows a trustworthy diagnostic, mainly for its tridimensional images possibility. In this situation it seems reasonable to question the classic cephalometric analysis, creating factors of comparison with computed tomography data. Aim: For this, it was considered the evaluation of the angle between the long axis of the inferior incisor and the mandibular plane (IMPA) in the lateral cephalograph and in the computed tomography. Methods: Nineteen patients, selected for orthodontic treatment, had constituted the sample of this study, 12 female and 7 male, with ages between 16 years and 4 months and 28 years and 2 months. After the collection of data made by two examiners, statistical analyses for the attainment of the errors intra and inter-examiners had been made, using level of significance of 5%. Results and Conclusion: It was concluded that IMPA can be measured in the lateral cephalometric radiographs with trustworthiness, even that its values were smaller when compared with the computed tomography.

Myositis ossificans traumatica of the medial pterygoid muscle: a case report.

In this report, we present a case of myositis ossificans traumatica (MOT) of the medial pterygoid muscle that had developed after mandibular block anesthesia administered for endodontic treatment of the lower right second molar, demonstrating typical features of this condition. MOT should be considered as a differential diagnosis when there is severe limitation of jaw opening and an associated trauma. Panoramic radiographs and axial and coronal computed tomography (CT) scans can effectively delineate the calcified mass. Other imaging studies that may be helpful include magnetic resonance imaging (MRI), bone scans, and ultrasound. As shown in our case, calcified masses were found in the right mandibular angle, which severely limited jaw opening. Some earlier reported cases of MOT were treated by extraoral surgical approaches with complete removal of the evolving muscle. The aim of this case report is to present only the diagnostic imaging aspects of myositis ossificans traumatica.

A CAD/CAM flapless surgical technique and immediate prosthesis: A clinical report

Background: This article describes a clinical report with a new system for guided surgical treatment and immediate load prosthesis in the flapless surgical technique. Case report: Based on a computed tomography (CT) of a 64 - year-old edentulous patient, the cross sections were reformatted and used to construct a virtual planning of the implants and a guide template in Dental Slice. Six dental implants were placed in the maxilla and mandible using a Slice Guide System. Following a 30-month in maxilla and 24-month in mandible healing period, the clinical and radiographic evaluation and computed tomography (CT) showed good clinical stability. The Slice Guide System proved satisfactory for the Flapless Surgical Technique in dental implants.

Neurocysticercosis: The enigmatic disease

Neurocysticercosis (NCC) is an infection of the central nervous system (CNS) caused by the metacestode larval form of the parasite Taenia sp. Many factors can contribute to the endemic nature of cysticercosis. The inflammatory process that occurs in the tissue surrounding the parasite and/or distal from it can result from several associated mechanisms and may be disproportionate with the number of cysts. This discrepancy may lead to difficulty with the proper diagnosis in people from low endemic regions or regions that lack laboratory resources. In the CNS, the cysticerci have two basic forms, isolated cysts (Cysticercus cellulosae = CC) and racemose cysts (Cysticercus racemosus = CR), and may be meningeal, parenchymal, or ventricular or have a mixed location. The clinical manifestations are based on two fundamental syndromes that may occur in isolation or be associated: epilepsy and intracranial hypertension. They may be asymptomatic, symptomatic or fatal; have an acute, sub-acute or chronic picture; or may be in remission or exacerbated. The cerebrospinal fluid (CSF) may be normal, even in patients with viable cysticerci, until the patients begin to exhibit the classical syndrome of NCC in the CSF, or show changes in one or more routine analysed parameters. Computed tomography (CT) and magnetic resonance imaging (MRI) have allowed non-invasive diagnoses, but can lead to false negatives. Treatment is a highly controversial issue and is characterised by individualised therapy sessions. Two drugs are commonly used, praziquantel (PZQ) and albendazole (ABZ). The choice of anti-inflammatory drugs includes steroids and dextrochlorpheniramine (DCP). Hydrocephalus is a common secondary effect of NCC. Surgical cases of hydrocephalus must be submitted to ventricle-peritoneal shunt (VPS) immediately before cysticidal treatment, and surgical extirpation of the cyst may lead to an absence of the surrounding inflammatory process. The progression of NCC may be simple or complicated, have remission with or without treatment and may exhibit symptoms that can disappear for long periods of time or persist until death. Unknown, neglected and controversial aspects of NCC, such as the impaired fourth ventricle syndrome, the presence of chronic brain oedema and psychic complaints, in addition to the lack of detectable glucose in the CSF and re-infection are discussed. © 2011 Bentham Science Publishers.

Tomographic, Histological, and Immunohistochemical Evidences on the Use of N-Butyl-2-Cyanoacrilate for Onlay Graft Fixation in Rabbits

Background: The bone tissue responses to Cyanoacrylate have been described in the literature, but none used N-butyl-2-cyanoacrilate (NB-Cn) for bone graft fixation. Purpose: The aims of the study were: (a) to analyze the bone grafts volume maintenance fixed either with NB-Cn or titanium screw; (b) to assess the incorporation of onlay grafts on perforated recipient bed; and (c) the differences of expression level of tartrate-resistant acid phosphatase (TRAP) protein involved in bone resorption. Materials and Methods: Eighteen New Zealand White rabbits were submitted to calvaria onlay grafting on both sides of the mandible. On one side, the graft was fixed with NB-Cn, while on the other hand the bone graft was secured with an osteosynthesis screw. The computed tomography (CT) was performed just after surgery and at animals sacrifice, after 1 (n=9) and 6weeks (n=9), in order to estimate the bone grafts volume along the experiments. Histological sections of the grafted areas were prepared to evaluate the healing of bone grafts and to assess the expression of TRAP protein. Results: The CT scan showed better volume maintenance of bone grafts fixed with NB-Cn (p≤0.05) compared with those fixed with screws, in both experimental times (analysis of variance). The immunohistochemical evaluation showed that the TRAP expression in a 6-week period was significantly higher compared with the 1-week period, without showing significant difference between the groups (Wilcoxon and Mann-Whitney). Histological analysis revealed that the NB-Cn caused periosteum damage, but provided bone graft stabilization and incorporation similar to the control group. Conclusion: The perforation provided by screw insertion into the graft during fixation may have triggered early revascularization and remodeling to render increased volume loss compared with the experimental group. These results indicate that the NB-Cn possesses equivalent properties to titanium screw to be used as bone fixation material in osteosynthesis. © 2010 Wiley Periodicals, Inc.

Meniscal mineralisation in little spotted cats

Background: The aim of this study was to evaluate the stifle joints of little spotted cats in captivity using radiographic and CT studies. The hypothesis was that these animals would have meniscal mineralisation that could be detectable by imaging studies. Twelve intact little spotted cats (Leopardus tigrinus), 2 females and 10 males, aged from 1.5 to 11.11 years old and weighing 1.9-3.05 kg were studied. These animals, which were living in the Quinzinho de Barros Municipal Zoo, had no symptoms or known disease processes at the time of the study. The plain radiographs and computed tomography (CT) scans of both stifle joints were performed under general anaesthesia. Sequential transverse images were acquired on a spiral scanner.Results: No signs of articular disease were observed in any of the animals. Radiographically, the meniscal mineralisation was detected as an oval radiopacity in the cranial compartment on the mediolateral projection, located within the area of the medial meniscus. On craniocaudal projection, the mineralisation was more difficult to visualise. In one of the animals, it was not possible to identify the meniscal mineralisation in either of the stifle joints. Using CT, meniscal mineralisation was best identified in the transverse plane images.Conclusions: Meniscal mineralisation appears to be a normal anatomic feature in little spotted cats. © 2013 Rahal et al.; licensee BioMed Central Ltd.

Bone morphology of the hind limbs in two caviomorph rodents

In order to evaluate the hind limbs of caviomorph rodents a descriptive analysis of the Cuniculus paca (Linnaeus, 1766) and Hydrochoerus hydrochaeris (Linnaeus, 1766) was performed using anatomical specimens, radiography, computed tomography (CT) and full-coloured prototype models to generate bone anatomy data. The appendicular skeleton of the two largest rodents of Neotropical America was compared with the previously reported anatomical features of Rattus norvegicus (Berkenhout, 1769) and domestic Cavia porcellus (Linnaeus, 1758). The structures were analyzed macroscopically and particular findings of each species reported. Features including the presence of articular fibular projection and lunulae were observed in the stifle joint of all rodents. Imaging aided in anatomical description and, specifically in the identification of bone structures in Cuniculus paca and Hydrochoerus hydrochaeris. The imaging findings were correlated with the anatomical structures observed. The data may be used in future studies comparing these animals to other rodents and mammalian species. © 2012 Blackwell Verlag GmbH.

Bone apposition to laminin-1 coated implants: Histologic and 3D evaluation

Laminin-1 has been reported as one of the factors responsible for the nucleation of calcium phosphates and, in vitro, has been reported to selectively recruit osteoprogenitors. This article focused on its in vivo effects, and evaluated the effect of laminin-1 local application on osseointegration. Polished cylindrical hydroxyapatite implants were coated with laminin-1 (test) and the bone responses in the rabbit tibiae after 2 and 4 weeks were evaluated and compared to the non-coated implants (control). Before the samples were processed for histological sectioning, they were three-dimensionally analysed with micro computed tomography (μCT). Both evaluation methods were analysed with regards to bone area around the implant and bone to implant contact. From the histologic observation, new bone formation around the laminin-1 coated implant at 2 weeks seemed to have increased the amount of supporting bone around the implant, however, at 4 weeks, the two groups presented no notable differences. The two-dimensional and three-dimensional morphometric evaluation revealed that both histologic and three-dimensional analysis showed some tendency in favour of the test group implants, however there was no statistical significance between the test and control group results. © 2012 International Association of Oral and Maxillofacial Surgeons.

Papel da tomografia torácica e abdominal no estadiamento do carcinoma mamário localmente avançado

Pós-graduação em Cirurgia Veterinária - FCAV