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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Verificação da proporção áurea em indivíduos dolicofaciais e mesofaciais, por meio de radiografias cefalométricas laterais /

Walter-Porto, Carolina de Oliveira Tocalino. January 2005 (has links)
Orientador: Edmundo Medici Filho / Resumo: Existe uma proporção constante identificada no corpo humano e na natureza, sendo conhecida e denominada como Proporção Áurea, gerada a partir da proporcionalidade que se expressa pelo número 1,618033, geralmente utilizado 1,618 (GIL, 2001). Conhecendo-se a importância estética e funcional de uma face considerada como sendo bela, o nosso propósito neste estudo foi colaborar com o Cirurgião-Dentista na busca do belo em indivíduos de dois grupos faciais; dolicofaciais e mesofaciais. Com isso, verificamos, por meio de radiografias cefalométricas laterais de indivíduos na faixa etária entre 17 e 25 anos de idade e com oclusão Classe I de Angle, se algumas medidas apresentavam-se em Proporção Áurea no esqueleto crânio-facial de 24 indivíduos dolicofaciais e 24 mesofaciais. A análise dos resultados obtidos nos permitiu concluir que, das oito razões estudadas, a Proporção Áurea esteve presente em quatro razões no grupo de indivíduos mesofaciais e em apenas uma razão no grupo de indivíduos dolicofaciais. / Abstract: There is a constant proportion identified in the human body and nature, known and denominated as Divine Proportion, generated from the proportionality that is expressed by the number 1.618033, generally used as 1.618 (GIL, 2001). Knowing the esthetic and functional importance of a face considered beautiful, the proposal of this study was to collaborate with the Dentist in search of beauty in individuals of two facial groups; dolichofacials and mesofacials. With this we verified, by means of lateral cephalometric radiographs of individuals between 17 and 25 years old and with Class 1 Angle occlusion, if some measurements in Divine Proportion were present in the facial skull of 24 dolichofacial individuals and 24 mesofacial individuals. The analysis of the obtained results allowed us to conclude that of the eight ratios studied, the Divine Proportion was present in four ratios in the group of mesofacial individuals and in just one ratio in the group of dolichofacial individuals. / Mestre
22

Desenvolvimento e teste de um modelo interativo para aprendizagem e calibragem em cefalometria radiográfica

Silveira, Heraldo Luis Dias da January 2008 (has links)
As análises cefalométricas computadorizadas baseiam-se na marcação de pontos anatômicos sobre imagens radiográficas digitalizadas. Estudos têm questionado o desempenho dos executores, tendo em vista a falta de reprodutibilidade dos exames. Tal fato, gera preocupação com a formação do profissional para a prática da cefalometria radiográfica. Desta forma, se faz necessária a criação de novas abordagens no ensino que permitam promover e consolidar conhecimentos e intervenções neste domínio. Dentro deste contexto, foram desenvolvidos um objeto virtual chamado Ceph-Learning para aprendizagem e um software intitulado Cyclops Cephalometry para treinamento e calibragem em cefalometria radiográfica. Especialistas em tecnologia educativa, ortodontia, alunos de graduação e pós-graduação testaram os produtos criados. Os resultados mostraram que estes apresentam-se como ferramentas úteis, eficientes e facilitadoras do processo de aprendizagem e calibragem, servindo de suporte para o aprendizado e prática da cefalometria. Conclui-se que a tecnologia virtual aplicada ao aprendizado assistido por computador é eficiente e melhora o desempenho acadêmico e profissional nos exames cefalométricos. / Computed cephalometric analysis is based on the identification of anatomical landmarks marked on digitized radiographic images. Some studies have been enquiring the performance of the examiner, considering the analysis lack of reproducibility. This outcome generates a concern regarding the academic training of the professionals responsible for the cephalometric analysis. Therefore, the creation of new educational approaches which could allow the promotion and consolidation of interventions within this domain is necessary. This context has lead to the development of a virtual object directed to teaching denominated Ceph-Learning and a calibrating and training software named Cyclops Cephalometry. Technology education and orthodontics specialists, undergraduate and graduate students have tested the developed products. Results show that these tools have facilitated the teaching and calibrating process proven to be useful and efficient, therefore, standing as a cephalometric practice and learning support. As a conclusion, virtual technology applied to computer-aided learning is efficient and improves the professional and academic performance regarding cephalometric analysis.
23

Proposta de um plano cefalométrico na avaliação da relação ântero-posterior entre a maxila e a mandíbula / cephalometric plane proposal in the anteroposterior jaw relationship assessment

Ewaldo Luiz de Andrade 07 November 2007 (has links)
Os métodos, mais divulgados na literatura, para a avaliação da relação ânteroposterior entre a maxila e a mandíbula, receberam considerações. Alguns utilizavam pontos cefalométricos em estruturas anatômicas longe da região avaliada (ângulo ANB), outros como a avaliação Wits apresentavam instabilidade e variação do plano oclusal e, o plano MM° Bisector ou a avaliação ProjUSP que utilizavam muitos pontos cefalométricos e uma complexa técnica de traçado cefalométrico. Para facilitar esta avaliação, propusemos a utilização do plano PmA, com projeção ortogonal apenas do ponto B, para que somente com 3 pontos fosse possível alcançar uma confiável avaliação da relação ântero-posterior entre a maxila e a mandíbula. Para tanto a correlação entre a avaliação (PlanUSP) e os ângulos ANB e FABA e as avaliações Wits e Tpi foi pesquisada em uma amostra com 85 indivíduos, sendo 47 Classe I e 38 Classe II de Angle. Com a análise estatística obtivemos significativa correlação entre a avaliação PlanUSP e as outras medidas e avaliações pesquisadas, tanto para indivíduos Classe I como Classe II de Angle. Conclusão: a avaliação PlanUSP mostrou ser um método com significativa correlação e homogeneidade com as medidas dos ângulos ANB e FABA e com os métodos Wits e TPi, na avaliação da relação ântero-posterior entre a maxila e a mandíbula. / The most published methods, for the anteroposterior jaw relationship appraisal, have got consideration. Some of them used cephalometric points in the anatomical structures far from the evaluated area (ANB angle), others as the Wits appraisal got instability and alteration of the occlusal plane and some others like MMº Bisector plane and ProjUSP evaluation used many cephalometric points and a complex cephalometric tracing technique. The aim of this paper is making easier the assessment of the anteroposterior jaw relationship by using the PmA plane with perpendicular drawing from just point B, with only a 3 point way, that may get possible a reliable anteroposterior jaw relationship assessment. The correlation among the PlanUSP appraisal and the ANB and FABA angles and the Wits and TPi appraisals was researched with a sample of 85 subjects (47 Class I and 38 Class II). The statistical analysis showed a significant correlation between the PlanUSP appraisal and the others measurements and evaluations researched, as if Class I or Class II subjects. Conclusion: The PlanUSP appraisal showed to be a method with a significant correlation and homogeneity with the ANB and FABA angles measurements and the Wits and TPi methods for the anteroposterior jaw relationship assessments.
24

Determinação do valor medio do indice de altura facial : (estudo em individuos brasileiros, da região de Piracicaba com oclusão clinicamente excelente)

Pallu, Vera Regina 06 August 1998 (has links)
Orientador: Maria Beatriz B. de Araujo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-07-24T18:22:21Z (GMT). No. of bitstreams: 1 Pallu_VeraRegina_M.pdf: 3768838 bytes, checksum: d9a89c72fdbf1b6bdb1a428ad28eabd3 (MD5) Previous issue date: 1998 / Resumo: O objetivo desta pesquisa foi avaliar as alturas faciais anterior (AFA) e posterior (AFP), a fim de estabelecer valores médios para o Índice de Altura Facial (IAF), numa amostra de 70 telerradiografias em norma lateral de, indivíduos brasileiros, da região de Piracicaba, sendo 35 do sexo masculino e 35 feminino, numa faixa etária de 11 a 17 anos de idade, com oclusão clinicamente excelente e não submetidos a tratamento ortodôntico. As proporções faciais estudadas estavam baseadas nas seguintes dimensões: altura facial anterior (Pp-Me), altura facial posterior (Ar-Go), bem como a razão entre a altura facial posterior e a altura facial anterior, descrita como Índice de Altura Facial. Os resultados mostraram que não houve diferenças estatisticamente significantes para as médias das alturas faciais anterior e posterior, assim como, para o índice de altura facial com relação as médias de sexo, indicando que não existiu dimorfismo sexual. As médias de idade para essas três dimensões também não mostraram diferenças 5, estatisticamente significantes, em ambos os- sexos. As alturas faciais anterior e posterior apresentaram um aumento constante e equilibrado durante o crescimento, que foi maior no sexo masculino do que no feminino, Porém, na idade de 17 anos houve uma tendência a diminuição dos valores para AFA e AFP. Os valores médios obtidos para altura facial anterior foi de 64,11 milímetros e para altura facial posterior foi de 51,14 milímetros. Para o índice de altura facial o valor médio obtido foi de 0.79 milímetros / Abstract: The aim of this study was to evaluate the anterior and posterior facial heights, to determine the average to the Facila Height Index seventy cephalometric radiographs taken fro Piracicaba children and adolescent, 35 female and 35 males, from 11 to 17years old presenting normal occlusion and nor submitted to previous treatment orthodontic. The facial proportions were studied, based on the following dimensions: ENA-Me (AFA); Ar-Go (AFP) and Facial Height Index (IAF) which was obtained dividing AFP per AFA. The results showed that there wasn¿t statistical difference for anterior and posterior facial heights and Facial Height Index to sex and age means, indicating that there were no sexual dimorfism. The mean anterior and posterior facial heights was stable and equilibrate during growth, from 11 to 16 years old and presenting a tendency to decrease in adhult age, grom 17 years old which was greater in the males than females. The mean anterior and posterior facial heights for studied sample was 64.11 mm and 51.14 respectivelly. The mean Facial Height Index was 0.79 / Mestrado / Ortodontia / Mestre em Odontologia
25

Digitized and computerized recordkeeping in dentistry (Orthodontics) : A Technologically Advanced Alternative to the Analysis and Storage of Study Models

Kleinloog, A.D. January 2002 (has links)
Magister Scientiae Dentium - MSc(Dent) / The research is aimed at investigating and finding alternatives to the physical necessity of producing and storing plaster casts or stone models of the tissues of the mouth. The quest for time and space is universal and the successful management of both results in stress free, financially stable and uncluttered work circumstances. Study models do playa very important role in diagnostics and treatment planning as well as communicating final results in Dentistry, especially in Orthodontic practice. Conventional study models are bulky, fragile, and expensive diagnostic tools produced from impressions taken of the patient's mouth and cast in plaster or stone. The storage of these records creates major space problems, and recalling or retrieving models at some later stage also causes logistical problems. Ideally, the tissues of the mouth could be scanned and from this a 3-D image produced on screen, which could later be milled (machining process of reproducing, explained in Appendix B) if necessary. Three dimensionally accurate, visually pleasing, reproducible, measurable and retrievable records, would be the solution. Computerizing dental records has already revolutionized the industry in the fields of Radiology and written patient data. This information is available at the click of a mouse, and integrated diagnostic tools can be displayed on screen. A thorough investigation of all methods of capturing dental data and 3D images from previously researched and publicized studies was conducted before attempting the latest technology. The final project involved: 1. requesting an introductory and explanatory demonstration on the scanning possibilities in South Africa 2. organizing and attending a demonstration of the laser and contact scanner on study models and impressions. 3. undergoing training in the use of a contact scanner. Computerizing of these results and comparing data derived from analyzing both study models and impressions, manually and digitally. 4. researching and collecting of data with engineering professionals, to establish the validity and viability of this method ( aiming to use uncomplicated, widely accepted and thoroughly applicable basic criteria in all experiments.) 5. evaluation of data statistically by a statistician. Discussion: Digitizing and computerizing of images derived from scanning the models or impressions offers the most attractive alternative for record keeping. Laser scanning disappointed in general due to the relative unavailability in South Africa, the expensive nature of the service elsewhere and limiting factors due to the sensitivity of the laser beam. It is the most promising alternative in future research, because of improved accuracy, higher speed of scanning, uniformity and reproducibility. Contact scanning proved to be available, reliable and adjustable. In most applications, the best results in terms of accuracy and quality of surface finish are obtained using contact scanning. The disadvantage of this method is the time factor and therefore it becomes expensive and economically not viable. The direct scanning of impressions, albeit with laser or contact scanning, remains a scientific and clinical viable option. Conclusion: Digital imaging is still a young technology and many aspects are not yet completely explored. It is a promising technology and its significance is increasing because it opens the door to diagnostic information. Another important development is that the software for digital imaging will become more integrated with other computerized dental applications in the dental office, enabling patient data between different and remote practices to be exchanged more easily. Further progress is not limited by a lack of available image processing tools but rather by our restricted understanding of the various components of diagnostic imaging in dentistry. A Bioengineering exhibition mounted by the University of Munich during a December 2000 conference, displayed a specially adapted CT Scanner that could scan information directly from the mouth. This leads to more possibilities of deriving images without impressions or study casts.
26

A photometric soft-tissue profile assessment in a Western Cape sample

Samsodien, Mogamat Gilmee January 1986 (has links)
Magister Chirurgiae Dentium (MChD) / Cephalometric norms for the soft-tissue profile presently utilized in this country, are based almost entirely on North American Caucasian and Negroid studies. Orthodontists use these standards as a guide in the treatment of all sections of the South African population. Various studies have conclusively shown that the soft-tissue profile differs both racially, and from country to country. In recent years the number of patients presenting for orthodontic treatment at the University of the Western Cape has increased significantly. The need has therefore arisen for the establishment of soft-tissue profile trends in the Western Cape area.
27

Effects of premolar extraction on airway dimensions: A retrospective cephalometric appraisal

Van Zyl, Luzaan January 2020 (has links)
Magister Scientiae Dentium - MSc(Dent) / Aim: The aim of this study was to assess the effect of retraction of anterior teeth on pharyngeal airway dimensions, after orthodontic treatment of bimaxillary protrusion cases by means of the extraction of four premolars. Method: A total of 88 lateral cephalometric radiograph pairs, consisting of a pre-treatment and post-treatment radiograph taken for orthodontic treatment of bimaxillary protrusion by means of extraction of four premolars, was used. The pharyngeal airway space, measured across three different levels, as well as the length of the maxilla and mandible were assessed for changes from pre-treatment to post-treatment. Pearson’s correlation coefficient was used to determine the degree to which the change in pharyngeal airway space was associated with the change in maxilla or mandible length. Results: The pre-treatment average pharyngeal airway space measurements were recorded as 15.23mm for the Superior Pharyngeal Airway Space, 11.63mm for the Middle Pharyngeal Airway Space and 13.56mm for the Inferior Pharyngeal Airway Space. The average reduction in the pharyngeal airway space was noted as 1.21mm, 1.64mm and 2.23mm respectively. All with statistically significant P values of <0.001.
28

Avaliação das estruturas anatômicas para sobreposição cefalométrica maxilar utilizando telerradiografias em norma de 45 graus

Bronzi, Evandro da Silva [UNESP] 21 January 2002 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-01-21Bitstream added on 2014-06-13T18:32:10Z : No. of bitstreams: 1 bronzi_es_me_arafo.pdf: 640601 bytes, checksum: 0d65746f66a182b139908ba7275d7753 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Um estudo cefalométrico longitudinal e retrospectivo foi desenvolvido com o propósito de estabelecer um cefalograma para a maxila, encontrar pontos cefalométricos estáveis na telerradiografia em norma de 45 graus, e ainda avaliar se as imagens obtidas de um lado da radiografia oblíqua são compatíveis com o outro lado. Foram selecionadas telerradiografias em norma de 45 graus de 25 indivíduos, com faixa etária entre 12 e 17 anos, apresentando maloclusões de Classe I e Classe II de Angle. Todos os indivíduos possuíam radiografias oblíquas iniciais e finais dos lados direito e esquerdo tomadas em um mesmo aparelho de raios X, com um intervalo de 8 a 16 meses. O principal critério de inclusão era a presença de implantes metálicos em todas as telerradiografias , para sobreposições dos traçados cefalométricos. Após estudos em crânio seco e inspeção visual foi sugerido um cefalograma para a maxila constituído das seguintes estruturas anatômicas: contorno da órbita, uma linha da base do crânio, a região do processo zigomático, limites de seio maxilar, a maxila, o processo zigomático da maxila do lado oposto, o osso zigomático do lado oposto e a órbita do lado oposto. Os pontos cefalométricos sugeridos para servir de parâmetro na sobreposição parcial da maxila, em telerradiografias em norma de 45 graus, foram divididos de acordo com o sentido analisado. No sentido vertical os pontos mais estáveis foram: OS, PZI, ENP e PZMO. No sentido horizontal os pontos sugeridos foram: PZP, PZPI, PZI, ENA e A. As alterações anatômicas ocorridas em todos os pontos cefalométricos do lado esquerdo foram iguais as do lado direito, não havendo diferença entre os lados da tomada radiográfica para telerradiografias em norma de 45 graus. / A longitudinal and retrospective cephalometric study was developed in order to establish a maxillary cephalogram, to identify stable cephalometric landmarks on 45° radiographs, as well as to evaluate if the obtained images from one side are compatible with the ones from the other side. Forty-five degrees cephalometric radiographs of 25 persons, aged between 12 and 17 years, presenting Angle malocclusion: Class I and Class II were selected. All the persons had pre and post right and left oblique radiographs obtained from the same X ray device, with an interval of eight to sixteen months. The primary inclusion criterion was the presence of metallic implants in all radiographs, to obtain the cephalometric tracings superimpositions. After studies in dried skulls and visual inspection, a maxillary cephalogram was suggested using the following anatomical structures: the orbital contour, a cranial base line, the zigomatic process area, maxillary sinus boundaries, the maxilla; the maxillary zygomatic process, zigomatic bone and orbit of the counter side. The cephalometric landmarks suggested to work parameter for maxillary superimposition in 45º cephalometric radiographs were separated in accordance with the evaluated plane. It can be suggested the use of OS, PZI, PNS and PZMO on vertical planes and PZP, PZPI, PZI, ANS and A on horizontal plane considered the points more stable and reproducible in the sample. The anatomical changes observed in all the cephalometric points of the left side were equivalent to the ones of the right side, with no differences between the sides on 45º cephalometric radiographs.
29

"Avaliação das estruturas anatômicas para sobreposição cefalométrica maxilar utilizando telerradiografias em norma de 45 graus" /

Bronzi, Evandro da Silva. January 2002 (has links)
Orientador: Maurício Tatsuei Sakima / Banca: Luiz Gonzaga Gandini Júnior / Banca: Paulo César Saquy / Resumo: Um estudo cefalométrico longitudinal e retrospectivo foi desenvolvido com o propósito de estabelecer um cefalograma para a maxila, encontrar pontos cefalométricos estáveis na telerradiografia em norma de 45 graus, e ainda avaliar se as imagens obtidas de um lado da radiografia oblíqua são compatíveis com o outro lado. Foram selecionadas telerradiografias em norma de 45 graus de 25 indivíduos, com faixa etária entre 12 e 17 anos, apresentando maloclusões de Classe I e Classe II de Angle. Todos os indivíduos possuíam radiografias oblíquas iniciais e finais dos lados direito e esquerdo tomadas em um mesmo aparelho de raios X, com um intervalo de 8 a 16 meses. O principal critério de inclusão era a presença de implantes metálicos em todas as telerradiografias , para sobreposições dos traçados cefalométricos. Após estudos em crânio seco e inspeção visual foi sugerido um cefalograma para a maxila constituído das seguintes estruturas anatômicas: contorno da órbita, uma linha da base do crânio, a região do processo zigomático, limites de seio maxilar, a maxila, o processo zigomático da maxila do lado oposto, o osso zigomático do lado oposto e a órbita do lado oposto. Os pontos cefalométricos sugeridos para servir de parâmetro na sobreposição parcial da maxila, em telerradiografias em norma de 45 graus, foram divididos de acordo com o sentido analisado. No sentido vertical os pontos mais estáveis foram: OS, PZI, ENP e PZMO. No sentido horizontal os pontos sugeridos foram: PZP, PZPI, PZI, ENA e A. As alterações anatômicas ocorridas em todos os pontos cefalométricos do lado esquerdo foram iguais as do lado direito, não havendo diferença entre os lados da tomada radiográfica para telerradiografias em norma de 45 graus. / Abstract: A longitudinal and retrospective cephalometric study was developed in order to establish a maxillary cephalogram, to identify stable cephalometric landmarks on 45° radiographs, as well as to evaluate if the obtained images from one side are compatible with the ones from the other side. Forty-five degrees cephalometric radiographs of 25 persons, aged between 12 and 17 years, presenting Angle malocclusion: Class I and Class II were selected. All the persons had pre and post right and left oblique radiographs obtained from the same X ray device, with an interval of eight to sixteen months. The primary inclusion criterion was the presence of metallic implants in all radiographs, to obtain the cephalometric tracings superimpositions. After studies in dried skulls and visual inspection, a maxillary cephalogram was suggested using the following anatomical structures: the orbital contour, a cranial base line, the zigomatic process area, maxillary sinus boundaries, the maxilla; the maxillary zygomatic process, zigomatic bone and orbit of the counter side. The cephalometric landmarks suggested to work parameter for maxillary superimposition in 45º cephalometric radiographs were separated in accordance with the evaluated plane. It can be suggested the use of OS, PZI, PNS and PZMO on vertical planes and PZP, PZPI, PZI, ANS and A on horizontal plane considered the points more stable and reproducible in the sample. The anatomical changes observed in all the cephalometric points of the left side were equivalent to the ones of the right side, with no differences between the sides on 45º cephalometric radiographs. / Mestre
30

Morphologie et croissance mandibulaires avec et sans hypodontie chez des sujets atteints de la séquence de Pierre Robin : une étude rétrospective

Sideris, Christos January 2009 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

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