Orientador: Solange Maria de Almeida / Tese (doutorado) - Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-15T20:48:17Z (GMT). No. of bitstreams: 1 Menezes_AlynneVieirade_D.pdf: 1911461 bytes, checksum: 9eed499fb3fe7db23a7c4de2811423d3 (MD5) Previous issue date: 2010 / Resumo: A utilização de implantes dentários para a reabilitação de regiões edêntulas é uma das atividades mais crescentes da Odontologia e a utilização de imagens é um fator essencial para se alcançar o almejado sucesso. Vários métodos de imagem vêm sendo utilizados com esse propósito e a tomografia computadorizada de feixe cônico (TCFC) vem se estabelecendo como um dos métodos promissores nesse sentido, pois se trata de um método confiável, capaz de produzir imagens em tamanho real, sem sobreposição e com dose de radiação menor que a tomografia computadorizada fan beam. Neste trabalho teve-se como objetivo avaliar a influência da posição da mandíbula na realização de medidas da altura e da espessura de sítios implantares em cortes ortorradiais de TCFC. Para tanto, foram utilizadas 10 mandíbulas maceradas, sendo obtidas imagens utilizando-se o tomógrafo de feixe cônico i-CAT. Foi realizada uma única imagem de cada mandíbula e a partir dessa imagem, os cortes ortorradiais foram obtidos considerando-se 3 diferentes posições: 1: base da mandíbula paralela ao plano horizontal (Posição Normal - PN); 2: base com inclinação de +10° (Posição Superior - PS) e 3: com inclinação de -10° (Posição Inferior - PI). A altura e a espessura óssea de cada região foram mensuradas por um único examinador e os dados obtidos nos grupos experimentais (PS e PI) foram comparados com os dados obtidos do grupo controle (PN) usando a análise de variância two-way (a=0,05). Os valores médios de altura e de espessura ósseas não variaram significativamente entre as posições inclinadas (PS e PI) e a posição padrão (PN), o que permite concluir que nas inclinações avaliadas, a direção do plano axial não influenciou nas medidas obtidas / Abstract: Dental implants have became part of routine treatment plans in many cases of edentulous patients and an important part of preimplant examination is provided by images of the existing bone structures in addition to the clinical findings. Several imaging modalities have been used for preimplant assessment and the cone-beam computed tomography may indeed be the next major advancement, since provides clinicians with accurate images of high diagnostic quality with relatively short scanning times and a reported radiation dose lower than fan beam computed tomography. The aim of this present study was to investigate the influence of mandibular inclination on the measured height and width of the cortical bone in reformatted cross-sectional cone beam computed tomography. Ten human dry mandibles were scanned with dental CBCT (i-CAT). It was performed only one scan of any mandible and reformatted cross-sectional scans were obtained at three different positions: (1) parallel to the lower border of the mandible (standard position); (2) with a inclination of +10° (Upper Position) and (3) with a n inclination of -10°(Lower Position). The alveolar bone height and width were measured for one examiner and data subjected to two-way analysis of variance and to compare the means obtained for the experimental groups (UP and LP) with the control group (standard position) (a=0,05). Mean values of bone height and width did not varied significantly between the inclined (UP and LP) and the standard positions. It could be concluded that in the positions analyzed, the direction of the axial planes did not influence the measurements obtained / Doutorado / Radiologia Odontologica / Doutor em Radiologia Odontológica

Thesis (MSc (Radiography))--Cape Peninsula University of Technology, 2018. / Introduction: Forensic dentistry plays a key role in identifying human remains that cannot be identified visually or by other means. Studies have shown that in cases of single or multiple deaths, scientific identification of human remains utilising forensic dentistry is often the most successful source of identification. Dental identification of human remains consists of a very complex procedure that makes it necessary during the investigation process to use and compare unique dental identifiers. A reliable and accurate method of identifying human remains is a positive radiological identification between ante-mortem and post-mortem images of dental radiographic images. Even if ante-mortem radiographic images may not be present during the identification process, post-mortem images may include details of dental restorations such as dental implants which cannot be seen during visual examination. The different types of dental implants vary in morphology and in conjunction with the unique appearance of dental anatomy and the placement of custom restorations such as dental implants, it has been found to accurately assist in the identification of human remains. Objectives: To establish a radiographic dental implant guide for ten commonly used dental implant types in the Western Cape, South Africa; and to identify and describe the morphological characteristics of these dental implant types as observed on pantomographs. Methods: The ten commonly used dental implant types were imaged radiographically to create a reference instrument which served as a tool for identifying and comparing different types of dental implants. The morphologies of the different dental implants, specifically the apex, thread and neck, were observed on ante-mortem pantomographs and compared to the appearance of the dental implants on the reference instrument to make a positive match. The straight tube image of all ten dental implant types in the reference instrument was used as the point of reference to positively identify the morphological characteristics of each dental implant type on the pantomographs. The morphological characteristics of the ten commonly used dental implant types used in the Western Cape were described and based on this a radiographic dental implant guide was developed. Results: A total of 384 dental implants were observed on the pantomographs. Of these, 380 dental implants could be positively identified on the pantomographs while 4 dental implants could not. A total of 350 dental implants (91%) were identified as dental implant types listed in the reference instrument while 30 dental implants were identified as a dental implant type not listed in the reference instrument. A total of 208 dental implants (54.2%) could be positively identified using the morphological characteristics namely the apex, thread and neck on the straight tube images of the dental implant type in the reference instrument. The radiographic dental implant guide was developed based on positive identification of the morphological characteristics of the dental implant types. Conclusion: This research study has illustrated that the morphology of dental implants can be used to differentiate between different dental implant types on pantomographs. Each dental implant type had unique morphological characteristics as well as similarities which enabled distinction between the different dental implant types, which facilitated dental implant identification and the development of a radiographic dental implant guide. The radiographic dental implant guide developed as part of this research study, may be useful in the field of forensic dentistry and forensic radiology.

Thesis (M.S.)--University of Michigan, 1972.

Thesis (M. Sc.)--University of Toronto, 1996. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--University of Michigan, 2006. / Includes bibliographical references.

Thesis (M.S.)--University of Michigan, 1972.

Thesis (M.S.)--University of Michigan, 1991.

Thesis (M. Sc.)--University of Toronto, 1996. / Includes bibliographical references.

Thesis (M.S.)--University of Michigan, 2001. / Includes bibliographical references.

Made available in DSpace on 2014-06-11T19:35:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-31Bitstream added on 2014-06-13T20:25:51Z : No. of bitstreams: 1 barao_var_dr_araca.pdf: 1603640 bytes, checksum: 5d48588f784413a0d8cc560b1ff6d9b0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Objetivos: (1) Investigar o papel de diferentes níveis de pH da saliva artificial (3; 6,5 e 9) no comportamento corrosivo do titânio comercialmente puro (cp-Ti) e da liga Ti-6Al-4V (Capítulo 1); (2) Avaliar a influência do processo de corrosão na afinidade do lipopolissacarídeo (LPS) de Escherichia coli para o cp-Ti e o Ti-6Al-4V (Capítulo 2); (3) Investigar a natureza tribocorrosiva do titânio em saliva artificial em presença de LPS (Capítulo 3); (4) Comparar o efeito de diferentes designs de overdentures implanto-retidas e prótese total fixa implanto-suportada na distribuição de tensões em mandíbula edêntula pelo método de elementos finitos tridimensional (Capítulo 4). Materiais e métodos: Testes eletroquímicos como potencial de circuito aberto, espectroscopia de impedância eletroquímica, e teste potenciodinâmico foram conduzidos. Para o teste de afinidade ao LPS, os espécimes foram tratados com LPS (1,5; 15 e 150 μg/ml) durante 24 horas para avaliar a aderência de LPS. Os discos foram transferidos a cada 24 horas para solução fresca de água livre de LPS até completar 72 horas, para investigar a liberação de LPS. No teste de tribocorrosão, o pH da saliva (6,5), a concentração de LPS (0, 0,15, 15 and 150 μg/ml), a duração do deslizamento (2000 ciclos), freqüência (1,2 Hz) e carga (20 N) foram usados para mimetizar o processo mastigatório. Finalmente, modelos tridimensionais de uma mandíbula edêntula foram construídos. No grupo OR a mandíbula foi restaurada com overdenture retida por implantes não esplitados com sistema de retenção O’ring; nos grupos BC-C e BC as mandíbulas foram restauradas com overdentures retidas por implantes esplintados com sistema de retenção barra-clipe associado ou não a cantilevers distais... / Objectives: (1) To investigate the role of different levels of pH of artificial saliva (pHs 3, 6.5 and 9) under simulated oral environment on the corrosion behavior of commercially-pure titanium (cp-Ti) and Ti-6Al-4V alloy (Chapter 1); (2) To assess the influence of corrosion process on Escherichia coli lipopolysaccharide (LPS) affinity for cp-Ti and Ti-6Al-4V alloy (Chapter 2); (3) To evaluate the tribocorrosive (corrosion/wear) nature of titanium in artificial saliva (pH 6.5) with LPS (Chapter 3); and (4) To compare the effect of different designs of implant-retained overdentures and fixed full-arch implant-supported prosthesis on stress distribution in edentulous mandible by using a three-dimensional finite element analysis. Materials and methods: Standard electrochemical tests, such as open circuit potential, electrochemical impedance spectroscopy, and potentiodynamic tests were conducted in a controlled environment. For LPS affinity test, specimens were treated with LPS (1.5, 15 and 150 μg/ml) for 24 hours to evaluated LPS adherence. Discs were then transferred every 24 hours to fresh LPS-free water, up to 72 hours, to investigate LPS elution. In the tribocorrosion test, the pH of saliva (6.5); LPS concentration (0, 0.15, 15 and 150 μg/ml), sliding duration (2000 cycles), frequency (1.2Hz) and load (20 N) parameters mimicked the mastication process. Finally, tridimensional models of an edentulous mandible were constructed. In the OR group, the mandible was restored with an overdenture retained by unsplinted implants with O’ring attachment; in the BC-C and BC groups, the mandibles were restored with overdentures retained by splinted implants with bar-clip anchor associated or not with distally placed cantilevers, respectively; in the FD group, the mandible was restored with a fixed full-arch implant-supported prosthesis... (Complete abstract click electronic access below)