Thesis (M.S.)--University of Michigan, 1975.

Thesis (M.S.)--University of Michigan, 2002. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S. (Orthdontics))--University of Tennessee Center for the Health Sciences, Memphis, 1980. / Spine title. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 54-59).

Thesis (M.D.S.)--University of Hong Kong, 1995. / Includes bibliographical references (leaves 42-57). Also available in print.

Thesis (M.S.)--University of Florida, 2006. / Typescript. Title from title page of source document. Document formatted into pages; contains 34 pages. Includes Vita. Includes bibliographical references.

Thesis (M.S.)--University of Florida, 2004. / Typescript. Title from title page of source document. Document formatted into pages; contains 31 pages. Includes Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 115-138).

CAPES / O presente trabalho estudou por meio do Método dos Elementos Finitos e por testes experimentais o efeito da distância interbraquetes, ativação e geometria (variáveis independentes) sobre o sistema de forças (Fx, Fy e Mz) produzidos por alças delta após ativação. As amostras foram produzidas com titânio-molibdênio, com secção transversal 0.017 x 0.025 polegadas (0,43mm x 0,64mm) e separadas em dois grupos (G1 e G2), com dez alças cada um. O grupo de alças G1 apresenta hastes com inclinação em suas extremidades. O Grupo G2 hastes com extremidades arredondadas. Visando identificar diferenças entre as médias populacionais devidas a três possíveis causas ou fontes de variação (variáveis independentes) e as interações entre as mesmas (geometria, distância interbraquetes e ativação), utilizou-se a método de análise de variância a três critérios de classificação, modelo fatorial completo (ANOVA). O método de análise de variância aceita ou rejeita a(s) hipótese(s) H0 de igualdade das médias populacionais. Se H0 for rejeitada, admite-se que pelo menos uma das médias é diferente das demais. Nestas condições utilizou-se o teste proposto por Games-Howell para variâncias heterogêneas, visando estabelecer comparações entre os diferentes tratamentos. Para estimar a constante elástica para os dois tratamentos (G1 e G2), utilizou-se a análise de regressão para verificar o grau de relacionamento entre os valores da variável resposta (força Fx) e a variável independente (ativação da alça). Os Grupos G1 e G2 apresentaram magnitudes de força compatíveis com as descritas pela literatura (houve variação de 81,65gf até125gf para o grupo G1 e de 92,45gf até 133,10gf para G2, aos 3.0mm e 4.0mm de ativação, respectivamente para Fx). As forças verticais Fy foram de 50gf e 16gf para G1 e G2, aos 4.0mm, respectivamente, e 52,15gf e 26,95gf para G1 e G2 aos 3.0mm de ativação, respectivamente. A constante de mola encontrada para os grupos estudados mostrou estar dentro de limites apropriados para uso clínico, resultando 27,95gf/mm para G1 e 32,09 para G2. A relação M/F aumentou à medida que as alças desativavam. As alças mostraram ser adequadas para a retração de caninos desde que ativadas até aos 4,0mm e reativadas após 2,0mm de desativação. A relação M/F média foi de 9,2mm aos 4,0 mm de ativação e de 13mm aos 3,0mm para G1 enquanto que para G2 os valores médios foram de 9,3mm aos 4,0mm de ativação e13mm aos 3,0mm. Não houve diferença significativa entre os grupos. A variável independente ativação causou diferença estatística significativa nos resultados das variáveis dependentes (Fx, Fy e Mz). As diferentes distâncias interbraquetes não influenciaram de maneira significativa o sistema de forças. A variável grupo influenciou de maneira significativa os valores de Fy e Mz. / The present study tested experimentally and by Finite Element Method the effect of inter-bracket distance (IBD), activation and geometry (independent variables) on the force system (Fx, Fy, Mz) produced by delta springs after activation. The springs were produced with titanium-molybdenum 0.017 x 0.025 in (0,43mm x 0,64mm), and separated in two groups (G1 and G2) with ten springs each one. The springs in group G1 presented angulated legs and in the group G2 rounded legs. Analysis of factorial variance averages caused by three possible variation (inter brackets distance, geometry and activation) sources and the interactions between them. Regression analysis was also performed to obtain the spring rate. Groups G1 and G2 presented force magnitudes which are compatible with the ones mentioned in the literature related to the subject (varying from 81,65gf to 125gf for G1 and from 92,45gf to 133,10gf for G2, at 3.0mm and 4.0mm of activation, respectively for Fx). The vertical Fy forces were 50 gf and 16gf for G1 and G2, at 4.0mm, respectively, and 52,15gf and 16,95 gf for G1 and G2 at 3.0mm of activation, respectively. The spring constants have proved to be within the levels which are appropriate for clinical use, resulting 27,95gf/mm for G1 and 32,09 for G2 groups. The mean moment-to-force ratio (M/F) was M/F=9,2mm at 4,0 mm of activation and 13mm at 3,0mm of activation for G1 group, whereas for G2 the mean values were M/F=9,3mm at 4,0mm of activation and M/F=13mm at 3,0mm. The M/F ratio incresead as the springs deactivated. There was no statistical differences between groups. IBD and geometry does not cause significative influence on force systems resulting from activations, but activation that produced statistical difference on force system (Fx, Fy and Mz).

Made available in DSpace on 2015-12-06T23:44:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2006 / Contexto: Mordida aberta anterior (MAA) ocorre quando incisivos superiores não tocam incisivos inferiores. A etiologia é multifatorial, incluindo: hábitos orais, padrão de crescimento desfavorável, aumento de tecidos linfáticos com respiração bucal. Vários tratamentos têm sido propostos para corrigir esta má-oclusão. As intervenções não são suportadas por forte evidência científica. Objetivos: O objetivo desta revisão sistemática foi avaliar tratamentos ortodônticos e ortopédicos para corrigir MAA em crianças. Estratégia de pesquisa: Estratégias de pesquisa foram desenvolvidas para a MEDLINE e elaboradas para as seguintes bases de dados: Cochrane Oral Health Group Trials Register, PubMed (1966-2005); EMBASE (1980-2005); Lilacs (1982-2005); BBO (Biblioteca Brasileira de Odontologia) (1986-2005); SciELO (1997-2005). Revistas chinesas foram manualmente pesquisadas e as bibliografias dos artigos foram checadas. Critérios de Seleção: Todos os ensaios clínicos controlados randomizados ou quasi-randomizados de tratamentos ortodônticos e/ou ortopédicos para correção de MAA em crianças. Coleta de dados e análise: Dois revisores, independentemente, avaliaram a elegibilidade de todos os artigos identificados. RR, NNT e intervalos de confiança de 95% foram calculados para dados dicotômicos. Os resultados expressos em dados contínuos foram apresentados conforme descritos pelo autor. Principais resultados: Vinte e sete estudos foram eleitos, três ensaios clínicos controlados randomizados foram incluídos, comparando: efeitos do Regulador de função de Frankel-4 (RF4) com treinamento de selamento labial versus não tratamento, bite-blocks com magnetos versus bite-blocks; grade palatina associada à mentoneira versus não tratamento. O estudo com bite-blocks magneto versus bite-blocks não pôde ser analisado porque os autores interromperam o tratamento antes do que o planejado em função de efeitos colaterais em quatro dos dez pacientes. RF4 com treinamento de selamento labial e grade palatina associada à mentoneira foram capazes de corrigir MAA. Nenhum estudo descreveu: processo de randomização, cálculo do tamanho da amostra, mascaramento nas análises de dados. Dois estudos avaliaram duas intervenções ao mesmo tempo. Portanto, os resultados devem ser vistos com cautela. Conclusões dos revisores: Há alguma evidência de que as intervenções RF4 com treinamento de selamento labial e grade palatina associada à mentoneira são capazes de corrigir MAA. Os estudos incluídos têm potenciais vieses, portanto, os resultados devem ser vistos com cautela. Mais ensaios clínicos randomizados são necessários para elucidar as intervenções para tratamento de mordida aberta anterior. / Background: Anterior open bite occurs when upper incisors do not touch lower incisors. The aetiology is multifactorial including: oral habits, unfavorable growth pattern, enlarged lymphatic tissue with mouth breathing. Several treatments have been proposed to correct this malocclusion, but interventions are not supported by strong scientific evidence. Objectives: The aim of this systematic review was to evaluate orthodontic and orthopaedic treatments to correct anterior open bite in children Search strategy: Search strategies were developed for MEDLINE and revised appropriately for the following databases: Cochrane Oral Health Group Trials Register; The Cochrane Central Register of Controlled Trials (CENTRAL): The Cochrane Library , current Issue; PubMed (1966 to 2005); EMBASE (1980 to 2005); Lilacs (1982 to 2005); BBO (Bibliografia Brasileira de Odontologia) (1986 to 2005); SciELO (1997 to 2005). Chinese journals were handsearched and the bibliographies from papers were retrieved. Selection criteria: All randomised or quasi-randomised controlled trials of orthodontic and/or orthopaedic treatments to correct anterior open bite in children. Data collection & analysis: Two authors independently assessed the eligibility of all reports identified. Risk ratios, NNT and corresponding 95% confidence intervals were calculated for dichotomous data. The results presented as continuous data were expressed as described by author. Main results: Twenty seven trials were eligible, and only three randomised controlled trial were included comparing: effects of Frankel's functional regulator-4 (RF4) with lip-seal training versus no treatment; repelling-magnet splints versus bite-block; palatal crib associated with high-pull chincup versus no treatment. The study with repelling-magnet splints versus bite-block could not be analysed because the authors interrupted the treatment earlier than planned due to side effects in four of the ten patients. RF4 associated to lip-seal training and removable palatal crib combined with high-pull chincup were able to correct anterior open bite. None study described: randomisation process, size sample calculation, there was no blinding in the cephalometric analysis and the two studies evaluated two interventions at the same time. So, these results should be viewed with caution. Reviewers' conclusions: There is some evidence that the interventions RF4 with lip-seal training and palatal crib associated with high-pull chincup are able to correct anterior open bite. Given that the trials included have potential bias, these results must be viewed with caution. So, recommendations for clinical practice can not be made based only on the results of these trials. More randomised controlled trials are needed to elucidate the interventions for treating anterior open bite. / BV UNIFESP: Teses e dissertações

Available commercial ceramic brackets are made of alumina either monocrystalline or polycrystalline. One major drawback of these brackets is fracture during archwire torsion or tipping. Another drawback is that each type comes in one shade only: transparent or translucent. Objectives: To fabricate orthodontic brackets from different esthetic materials and evaluate their mechanical properties; to introduce extremely low profile miniature zirconia brackets and evaluate their torsional fracture strength; also, to fabricate brackets in shades comparable to natural tooth shades, and compare them to commercial ceramic brackets under different lights. Materials and Methods: CAD/CAM technology was used to mill brackets from: ParadigmTM MZ100 and LavaTM Ultimate resin composite; Mark II feldspathic porcelain; and In-Ceram® YZ zirconia. The brackets were subjected to two separate tests (torque and tipping). The average moments necessary to fracture the brackets were determined and compared to those of commercial alumina brackets, Mystique® MB and Resolve®. Also, miniature zirconia brackets were fabricated and subjected to torsion till failure. Static fatigue test was performed on standard YZ, MZ100, and Mystique brackets. Brackets were fabricated using CAD/CAM in shade A3 materials: MZ100; Lava Ultimate; and Mark II. Zirconia and alumina brackets were also fabricated and colored. Adobe Photoshop software was used to determine ΔE values between the brackets and A3 acrylic teeth from digital images taken under three different lights (daylight, fluorescent, and incandescent). The shaded brackets were compared to commercial alumina brackets: Inspire ICETM; Radiance PlusTM; Avex® CX; and Mystique® MB. Results: Standard zirconia brackets had the highest torsional and tipping strength among the tested esthetic brackets. Miniature zirconia brackets showed comparable or even statistically significantly higher resistance to archwire torsion than commercial alumina brackets. Standard zirconia brackets showed the highest survival rate of 83%. Under daylight, Radiance Plus and Lava Ultimate brackets had the smallest mean ΔE values. Lava Ultimate brackets had the smallest mean ΔE under fluorescent and incandescent light. Conclusions: Esthetic brackets can be fabricated in extremely low profile and smaller dimensions from zirconia with fracture strength comparable to the bulkier commercial alumina brackets. Also, brackets can be produced in natural tooth shades enhancing their esthetic appearance. / 2018-09-28T00:00:00Z