434 resultados para tomografia komputerowa
Resumo:
Class II malocclusion features a high prevalence in Brazil, being considered as a routine in orthodontic clinics. A number of appliances are shown in the literature in order to correct Class II malocclusion with mandibular retrusion. Herbst´s fixed functional appliance, idealized by Emil Herbst (1905) and reintroduced, in the 1980´s, by Hans Pancherz is highlighted for maintaining the mandible continuously advanced, showing a shorter active treament time, an immediate esthetic impact on the facial profile, as well as requiring no patient´s commitment. Recent researches indicate the use of this appliance in individuals after pubertal growth surge. The aim of the present study is to show the orthodontics practitioner the option to use this appliance so as to treat Class II in individuals after the growth surge, obtaining satisfactory outcomes and further Class II correction.
Resumo:
The aim of this study was to evaluate the clinical, tomographic, and histological similarity within the use of HA+β-TCP (Boneceramic) alone or associated with enamel matrix derived (EMD) proteins in sinus lifting procedures with subsequent dental implant placement. We selected two patients with residual bony ridges between 3 mm and 5 mm in height in need of bone grafts. Six months later, eight implants were installed (two implants at each site). Biopsies were made, and the tissue was processed and stained with HE solution. Tomographic evaluation showed bone height gain up to 10.0 mm on average. Histology showed new bone formation for both groups, with similar bone density and trabecular interconnectivity. It can be concluded that the HA+β-TCP graft isolated or associated to EMD provided bone height gain in sinus lifting procedures, with similar clinical, tomographic and histological characteristics.
Resumo:
The technology, through the advent of new equipments that allow imaging exams, has helped very much in the diagnosis and prognosis of diseases in Dentistry. The use of informatics, in general, in the manufacture of clinical reports is increasingly present in the dental offices. The legal validity of these systems is questioned, and is matter of discussion. This work makes considerations about Imageology or Diagnostic by image, a new area that is appearing on Dentistry. Among other exams, there are: digital radiography, tomography, computed tomography, artomography, magnetic resonance, computed cefalometry and ultra-sonography. It permits the professional to obtain a better diagnostic, and to the patient, the visualization of his problem and treatment. A survey on the possibilities of using informatics in Dentistry, particularly in Radiology, was also carried out, as well as the legal aspects, which are in accordance with the Law 8.935/94, what guarantees its practicability. Digital Certification is a mechanism that provides legal validity to documents and, as such, to radiographic images and others. It is a procedure that the dentist should take to ensure that he/she has safeguarded the judicial proofs that may be necessary in an eventual demand.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Pós-graduação em Biopatologia Bucal - ICT
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Background: To establish the best methodology for diagnosis and management of patients with solid and complex renal masses by comparing the costs and benefits of different imaging methods and to improve differential diagnosis of these benign and malignant lesions, particularly by investigating tumour calcifications. Methods: We performed a prospective study on 31 patients with solid or complex masses by submitting them to Abdominal Ultrasonography (US), Doppler Ultrasonography of the renal mass (US Dop), Computed Tomography (CT), and Magnetic Resonance Imaging (MRI). Results: We found 28 patients with malignant and three with benign masses. Of the 28 malignant, 17 showed calcifications at CT; 16 central and one was of the pure peripheral curvilinear type (egg shell). Excretory Urography (IVP) had a significantly lower detection rate for central calcifications than both US and CT. Benign and malignant masses appeared as described in literature, with US, CT and MRI showing high sensitivity and specificity in renal tumor diagnosis. The exception was US Dop where we obtained lower sensitivity for the characterization of malignant tumor flow. Conclusions: In this series we were surprised to find that CT revealed central calcifications in 51.6% of patients, all with malignant lesions, while, literature reports a frequency of calcification in renal cell carcinoma between 8 and 22%, in studies using abdominal films and EU (IVP). This finding is of great importance when we consider that these calcifications occur particularly in malignant neoplasms. As a result of comparing these different imaging methods we have developed a better methodology for renal tumor investigation.
Resumo:
The contamination of the physical environment occurs as a result of the lack of planning and inadequate management of hazardous products. Due to the difficulty of the characterization and study of soil and groundwater, the contamination has been long neglected. The characterization of these areas by research techniques through direct methods such as physical and chemical analysis, are widely used in the diagnosis and monitoring. However, despite presenting quantitative results, this method is not representative in spatial terms. The purpose of this work is to bring geophysical complementation with the diagnosis, bringing the spatial element for the detection of the contamination plume. In the study area, there was a railway accident in 1999 in which three wagons fell and spilled 240,000 L of diesel onto the soil. The main objective is to assess the presence of contaminants in the residual phase and dissolved in the subsurface, using the technique of Electrical Tomography (ETR), understand the effects of natural attenuation process in the degradation of hydrocarbons and changes in electrical properties in soil and groundwater. The results allowed the definition of three distinct patterns of resistivity region with presence of dissolved phase, set in a historical chemical analyzes: low values (> 60Ω.m) associated with the presence of hydrocarbons in an advanced stage of degradation, intermediate values (260Ω.me 511Ω .m) indicative of coexistence of residual hydrocarbons and dissolved phase, and high values (> 1000Ω.m), which reveal the prevalence of residual phase with incipient degradation, possibly in high toxicity concentrations for effective action of biodegradation processes. The diagnostic of areas with potential accumulation of residual phase can subsidize the planning of remediation techniques and promote the complete decontamination of the area
Resumo:
Introduction: The odontogenic keratocyst tumor (OKT) derived from dental lamina rests with particularities and specific histological features, with high rates of relapse and aggressive clinical behavior. Presents certain predilection for males, affecting the mandible of 60% to 80% of cases may be related to impacted tooth 25 to 45% of cases. Objective: To highlight the clinical, histopathological and imaging procedures of the OKT, as well as discuss the treatment of this injury. Case Report: To report a case of 10 years of age to look for the orthodontist to correct anterior open bite was observed in panoramic radiography radiolucent area in the region of the body of the mandible associated with pathological inclusion of the lower premolar. It was performed an incisional biopsy of the lesion and the histopathologic diagnosis was odontogenic keratocyst tumor. It was performed a CT scan to assess the extent of the injury and its relation to anatomic structures. How to conduct, we opted for the extraction of the deciduous molar and enucleation of the lesion, preserving the premolar included. The same goes on clinical and radiographic control 18 months, after removal of OKT obtaining the eruption of premolar that was involved in the injury. Final Comments: It is necessary to adopt protocols that include dental care knowledge of oral diagnosis, medical history and careful clinical evaluation without forgetting the need for histopathological confirmation.
Resumo:
The aim of this study was to evaluate the biomechanical behavior of different implant connection types, by means of three-dimensional finite element analysis. 3 Three-dimensional models were created with a graphic modeling software: SolidWorks 2006 and Rhinoceros 4.0, and InVesalius (CTI, São Paulo, Brasil), the bone was obtained by computerized tomography of a sagittal section of the molar region. The model was composed by bone block with an implant (4 x 10 mm) (Conexão Sistemas de Prótese, São Paulo), with different implant connections: external hex, internal hex and Morse-taper with the corresponding prosthetic component Ucla or Morse-taper abutment. The Three-dimensional models were transferred to finite element software Femap 10.0 (Siemens PLM Software Inc., CA, USA), to generate a mesh, boundary conditions and loading. An axial (200N) and oblique load (100N) was applied on the occlusal surface of the crowns. Analyses were performed using the finite element software NEiNastran 9.0 (Noran Engineering, Inc., USA) and transferred to the Femap 10.0 to obtain the results; after the results were visualized using von Mises stress maps and Maximum stress principal. The results showed the stress distribution was similar between models, with a little superiority of Morse-taper connection. It was concluded that: the three connection types were biomechanical viable; The Morse-taper connection presented the better internal stress distribution; there was not significant biomechanical differences on the bone.
Resumo:
As ossificações do complexo estilo-hióideo (OCEH), os tonsilólitos e os ateromas são exemplos calcificações em tecidos moles incidentalmente encontrados em exames de imagem. Atualmente com a utilização da tomografia computadorizada de feixe cônico (TCFC) na odontologia, há um aumento do número desses achados. Objetivo: Relatar um caso clínico com calcificações em tecidos moles e comparar esses achados entre a radiografia panorâmica e a TCFC do mesmo paciente. Paciente masculino, 77 anos, compareceu a Clínica de Radiologia para realizar radiografia panorâmica e TCFC para planejamento de implantes. Na radiografia panorâmica pode-se observar a OCEH bilateral e presença de uma área radiopaca localizada no ramo ascendente da mandíbula, que foi compatível com esclerose óssea. Na análise da TCFC constatou a presença da OCEH bilateralmente. Porém a área radiopaca primeiramente sugestiva de esclerose óssea, na TCFC foi sugerida como tonsilólito, pois não estava localizada no ramo ascendente da mandíbula, e sim nos tecidos moles da região próxima aos espaços aéreos. No exame de TCFC foi possível a visualização de outra estrutura calcificada do lado direito do paciente, na altura da vértebra C4, heterogênea que foi compatível com ateroma. O diagnóstico das calcificações pode não ser preciso quando se utiliza apenas a radiografia panorâmica, além da possibilidade de apresentar falso negativo, como no caso do ateroma. Assim sendo quando o paciente possuir o exame de TCFC esse deve ser completamente avaliado, para que sejam diagnosticadas as possíveis calcificações em tecidos moles presentes.
Resumo:
O cementoblastoma é uma neoplasia benigna que envolve dentes vitais, frequentemente os molares ou pré molares inferiores. Está associado à raiz dentária podendo provocar a sua reabsorção. Cresce muito lentamente e é assintomático, com exceção dos casos em que há expansão das corticais. Radiograficamente aparece como uma massa radiopaca, bem definida, com contorno radiolúcido, que se sobrepõe à raiz do dente. O diagnóstico final normalmente é feito pelo exame histopatológico, mas o diagnóstico clínico é facilmente realizado, através da avaliação radiográfica. Paciente leucoderma, do sexo masculino, 54 anos realizou uma radiografia panorâmica digital para uma avaliação geral. Na imagem, foi observada uma massa radiopaca, bem delimitada, medindo aproximadamente 2 cm de diâmetro envolvendo as raízes do dente 47. Para uma melhor avaliação do caso, foi realizada uma tomografia de feixe cônico, onde foi observada que a massa radiopaca estava aderida às raízes do dente 47, causando reabsorção externa das mesmas, apresentando as dimensões de aproximadamente 2,7 cm no sentido ântero-posterior, 2 cm da base da mandíbula em direção à cortical alveolar e 1,7 cm de vestibular para lingual. Foi também observada expansão da cortical óssea lingual, sem rompimento. O diagnóstico por meio da tomografia foi de cementoblastoma. Devido à idade do paciente e a ele não apresentar sintomatologia, foi proposto o acompanhamento da lesão. O paciente encontra-se em proservação há 18 meses e não houve alteração do quadro clínico.
Resumo:
Introduction: the granular cell odontogenic tumors are an uncommon neoplasm with benign clinical behavior. The lesion occurs over a wide age range with a typically predilection for the mandibular canine and molar regions. Aim: present a granular cell odontogenic tumor literature review. Conclusions: the tumor don’t present an aggressive biological behavior although recurrences can occur. The lesion is treated by conservative surgery with curettage and enucleation as election procedures.
Resumo:
Pós-graduação em Ciências Odontológicas - FOAR