Thesis (M.S.)--Ohio State University, 2009. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 108-109).

Thesis (M.S.)--Mechanical Engineering, Georgia Institute of Technology, 2005. Directed by Richard Neu. / Johnson, Steven, Committee Member ; McDowell, David, Committee Member ; Neu, Richard, Committee Chair. Includes bibliographical references.

Thesis (M.D.S.)--University of Hong Kong, 2003. / Also available in print.

Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 203-209).

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 124-127).

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 56-62).

Thesis (M.Sc.)--City University of Hong Kong, 2004. / At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Aug. 31, 2006) Includes bibliographical references.

Thesis (Ph.D.)--McMaster University, 2005. / Advisor: M.A. Elbestawi. Includes bibliographical references. Also available online.

Thesis (Ph. D.)--Oregon Graduate Center, 1985.

Made available in DSpace on 2014-06-11T19:27:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-02Bitstream added on 2014-06-13T18:55:40Z : No. of bitstreams: 1 seixas_mr_me_guara.pdf: 4578548 bytes, checksum: 654971c9dbf6bacfe64f0af3970c20b8 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nos últimos anos, ligas de níquel-titânio têm sido usadas em odontologia devido suas propriedades mecânicas favoráveis e resistência a corrosão. Portanto, no meio ambiente oral, elas são sujeitas a fluidos agressivos e variação de pH podendo levar a liberação de íons de níquel para tecidos e fluidos do corpo. Modificações na superfície destas ligas têm sido realizadas usando tratamentos mecânico, eletroquímico, químico e físico. Carbono amorfo hidrogenado (a-C:H) obtido por técnicas de deposição tem muitas propriedades atrativas tais como alta dureza superficial, inércia química e biocompatibilidade. Desse modo, como a fricção é em função das superfícies dos braquete e fios, o propósito deste trabalho foi avaliar a influência do tratamento de superfície na fricção de fios ortodônticos. Neste estudo in vitro, filmes a-C:H foram depositados em fios ortodônticos de níquel-titânio empregando a técnica PECVD (Deposição Química por Plasma de Rádio frequência). O arranjo estrutural dos filmes de DLC foi avaliado por espectroscopia de Raman e a adesão por ensaio de risco (scratching). As amostras foram divididas em dois grupos, com e sem tratamento de superfície e as forças friccionais foram avaliadas empregando-se um dispositivo confeccionado em laboratório. Os valores obtidos foram comparados usando test t-student. O resultado mostrou que fios de NiTi não tiveram uma diferença estatística significante (P>0,05) na fricção após tratamento de superfície / In the last years, nickel-titanium alloys have been used in dentistry due their excellent mechanical properties and corrosion resistance. However, in oral environment, they are subject aggressive fluids and pH variation can be leave nickel ions release to body tissues and fluids. Surface modifications of these alloys have been realized using mechanical, electrochemical, chemical and physical treatments. Hydrogenated amorphous carbon (a-C:h) prepared by deposition techniques have very attractive properties such as high hardness, chemical inertness and biocompatibility. Thus, as the friction is a function of the surfaces of the wires and brackets is very important to evaluate them after the coating. The purpose of this work was to evaluate the influence of surface treatment in the friction of the orthodontics wires. In this vitro study,a -C:H films were deposited on orthodontics bracket by r.f. plasma-enhanced chemical vapour deposition (PECVD). The structural arrangement of DLC films was probed by Raman spectroscopy and adhesion was eveluated by scratching. Samples were divided in two groups, with and without surface treatment and frictional forces were measured with a custom made jig. The values obtained were compared using student's t-test. The results showed that NiTi wires no had a statistically significant differenc (P.0,05) in friction after surface treatment