Thesis (Ph. D.)--Florida State University, 2005. / Advisor: Dr. Jim P. Zheng, Florida State University, College of Engineering, Dept. of Electrical and Computer Engineering. Title and description from dissertation home page (viewed Sept. 15, 2005). Document formatted into pages; contains xii, 96 pages. Includes bibliographical references.

Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains ix, 106 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 102-105).

Thesis (M.S.)--University of Alabama at Birmingham, 2007. / Description based on contents viewed June 25, 2007; title from title screen. Includes bibliographical references (p. 41).

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 80-84). Also available on the Internet.

Made available in DSpace on 2014-06-11T19:28:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-02-27Bitstream added on 2014-06-13T20:58:46Z : No. of bitstreams: 1 ticianeli_mg_me_arafo.pdf: 1350387 bytes, checksum: ea0f36454c6c9f5c29da9a1476668be1 (MD5) / Este estudo avaliou a eficiência de diferentes técnicas de acabamento e polimento sobre duas cerâmicas odontológicas (Duceram Plus e Duceram LFC), em relação à rugosidade média superficial (Ra). Foram preparados quarenta discos com 8 mm de diâmetro e 4 mm de espessura para cada uma das cerâmicas utilizadas, seguindo-se as recomendações do fabricante. Previamente ao glazeamento, todos os corpos-de-prova foram regularizados com o auxílio de lixas d'água de diferentes granulações (240,360 e 600, nesta ordem), recebendo, em seguida, uma camada de glaze. Os 40 corpos-de-prova de cada cerâmica foram divididos em 8 grupos com 5 representantes em cada um, recebendo diferentes tratamentos de superfície: T1- glaze; T2- desgaste com ponta diamantada fina e ultrafina; T3- T2 + sistema de acabamento e polimento dental Sof-Lex (3 M); T4- T3 + pasta diamantada; T5- T2 + kit de polimento Super-Snap (Shofu); T6- T5 + pasta diamantada; T7- T2 mais borrachas abrasivas Viking (KG Sorensen); T8- T7 + pasta diamantada. Foram realizadas cinco mensurações de rugosidade média (Ra, em æm) em cada corpo-de-prova, utilizando-se um rugosímetro ajustado com cut-off de 0,25 mm, extensão de tracejamento de 1,25 mm e velocidade de medição de 0,10 mm/s. Os resultados foram analisados estatisticamente pelos testes ANOVA e Tukey, com nível de significância de 5%. Os melhores tratamentos para ambas as cerâmicas avaliadas foram T3, T4, T5 e T6, apresentando semelhança estatística entre si; O glazeamento (T1) foi similar estatisticamente aos tratamentos T3, T4, T5 e T6 para a cerâmica Duceram LFC, em relação ao fator Ra; O tratamento T1 apresentou-se com diferença estatisticamente significante e mais rugoso que o tratamento T3, T4 e T6 para a cerâmica Duceram Plus, em relação ao fator Ra; As duas cerâmicas odontológicas avaliadas apresentaram... / This study assessed the efficacy of different current porcelain finishing and polishing procedures on two different dental ceramic (Duceram Plus and Duceram LFC) quantitatively with a profilometer. Forty disks (8 mm in diameter and 4 mm thick) were prepared for each dental ceramic according to the manufacturer's directions. Prior to glazing, all specimens' surfaces were abraded using a 240, 360 and 600-grit wet sandpaper. Then, all samples were glazed. The forty samples of each dental ceramic were divided into 8 groups of five specimens each, according to the surface treatment: T1- glaze; T2- abraded with fine and ultra fine diamond burs (KG Sorensen); T3- T2 following Sof-Lex (3M) polishing system; T4- T3 following diamond paste; T5- T2 following Super-Snap polishing kit (Shofu); T6- T5 following diamond paste; T7- Viking rubber wheels (KG Sorensen); T8- T7 following diamond paste. Five roughness measurements (Ra, æm) were performed on each disc using a profilometer with cut-off value of 0.25 mm and a tracing length of 1.25 mm and a speed of 0.1 mm per second. These values were tested using a two-way analysis of variance and Tukey test at 5% significance level. The result showed (to Ra factor) that T3, T4, T5 and T6 were the best surface treatment for both dental ceramic materials and were statistically equals; the glazed treatment (T1) was similar statistically to the polishing treatment T3, T4, T5 and T6 for Duceram LFC ceramic; the glazed treatment (T1) was different statistically and rougher than the polishing treatment T3, T4 e T6 for Duceram Plus ceramic; the two different dental ceramic had similar behavior when received the same surface treatment; and the diamond-abraded group (T2) had the rougher surface in both dental ceramic studied.

Contact between rough surfaces occurs in numerous engineering systems and in many instances influences the macro behavior of the system. In many instances, the interaction between rough surfaces, affect the macro behavior of the system. Effective treatment of systems containing rough surface contact requires multiscale modeling and analysis approach. It is the goal of this research to develop simple methods for treating contact of rough surfaces so as to facilitate multiscale analysis of systems containing rough surface contact and friction. This dissertation considers a multi-scale approach that includes interaction at nano-scale, micron-scale and accounting for their cumulative effect as to what we normally perceive to be the influence of contact surfaces and friction. In linking each scale to a higher scale this study employs statistical means to obtain cumulative effect of smaller-scale features. A mixed interactive/optimization technique is used to derive, in approximate closed form, equations for the contact load and real area of contact dependence on approach and parameters of rough surfaces. The equations so derived relate the normal and tangential components of contact load to displacement and surface parameters for three types of contact. The nature of contact interaction that include elastic, elastic-plastic, visco-elastic, and visco-elasto-adhesive behavior are considered and equations relating the normal and tangential contact load to approach and relative sliding are obtained in approximate closed form. The approximate equations provide a tool for efficient calculation of contact force components, especially in surface optimization efforts where repetitive calculation of contact force components may be needed. The approximate equations also facilitate a multi-scale dynamic analysis wherein the effect of contact interaction can be readily included in a mechanical system model. Several dynamical problems involving mechanical systems with friction contact are presented and nonlinear dynamic analyses are employed to link the micron-scale properties of surface to the macro-scale properties of the mechanical system. These lead to, perhaps, the first derivation of contact frequency and damping in rough surface contact.

PURPOSE: To determine the potential discoloration of provisional materials by exposure to beverages and evaluate the efficacy of simulated tooth-brushing on stain removal and the effect on surface roughness. METHODS: Materials included: Jet Set-4 (Lang), Protemp Plus (3M ESPE), Luxatemp (DMG), Artbloc (Merz), Telio-CAD (Ivoclar), and Vita-CAD (Vita). Specimens (n=10/group) were immersed in: distilled water, coffee, red wine, tea, coke and cranberry juice. Color measurements were taken (Xritei5 spectrophotometer) at: baseline, 24 hours, 4 and 8 weeks. Specimens in coffee and red wine for 8 weeks were exposed to tooth-brushing for three minutes and color measurements were taken subsequently. Color differences (ΔE) after treatments were calculated using one-way ANOVA, MANOVA and post hoc Tukey test. Another group of specimens (n=10/group) were exposed to tooth-brushing under a 1.91N load using toothpaste slurry (Crest® Cavity Protection) for 20,000 cycles in two modes: soft and medium bristles (both Oral B Indicator®). Surface roughness was measured using a Mitutoyo SJ201 profilometer before and after brushing. Surface roughness Ra values were compared using one-way ANOVA and post hoc Tukey test. RESULTS: Coke and water had no significant discoloration effect (p>0.05). Red wine and coffee exhibited the highest discoloration effect. CAD-CAM blocks showed significantly lower color change, at all durations, and after brushing (p<0.001). Tooth-brushing had a significant effect (Ra) on Telio-CAD, Artbloc, Jet Set-4 and Vita-CAD. Protemp-Plus and Luxatemp groups showed no significant difference. CONCLUSIONS: Traditional materials showed less color stability when compared to CAD/CAM blocks. Tooth-brushing effect varies depending on bristle and material type.

Surface roughness is an important parameter in the automotive Industry. This thesis is a study conducted in collaboration with QSO Interferometer systems AB (QSAB), Halmstad. The study is focused on the existing surface roughness parameters used in the automotive industry and the relationship to the CWS parameters of QISAB. The study also investigates the scope of CWS instrument developed by QISAB as a next-generation automated surface testing inline instrument. The initial study which has been conducted had 5 stages, those are the history of roughness measurement, the basic CWS parameters, the currently used surface testing instruments in the automobile industry, the use of surface metrology in the manufacturing industry and the basic principle and theory of the CWS. As the final stage to achieve the aim of the thesis a quantitative study has been conducted to compare the existing parameters with CWS parameters. The three type of comparison were done on a test piece having different range of surface roughness after different stages of grinding. These three comparisons that had been done were CWS v/s White light interferometer v/s visual inspection. The results from those quantitative analysis did support the results from the qualitative analysis.

Orientador: Márcio Zaffalon Casati / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-16T22:38:20Z (GMT). No. of bitstreams: 1 Diefenbach_AnaLucia_M.pdf: 6428742 bytes, checksum: 0c06242da8f41dfb2cd02646ac4e0208 (MD5) Previous issue date: 2010 / Resumo: Os procedimentos capazes de descontaminar a superfície implantar removendo o biofilme garantem o sucesso e a longevidade dos implantes. As conseqüências na rugosidade superficial gerada por esses procedimentos têm sido avaliadas, porém novas propostas para descontaminação das superfícies implantares vêm sendo utilizadas, principalmente para o tratamento da periimplantite. Assim, objetivo deste trabalho foi avaliar, in vitro, a rugosidade superficial de discos cilíndricos de titânio após uso de cureta plástica; jato de bicarbonato; esfregaço de tetraciclina e ultrassom piezoelétrico. Foram utilizados 50 discos de titânio com dimensões de 5 mm de altura por 5 mm de largura, com superfícies jateadas com óxido de alumínio. Os discos foram divididos aleatoriamente em cinco grupos experimentais. Grupo 1(n=10) controle - sem tratamento; grupo 2(n=10) - recebeu 15 movimentos de raspagem com cureta plástica; grupo 3(n=10) - aplicação de jato de bicarbonato por 30s a cinco milímetros da superfície; grupo 4(n=10) - aplicação de tetraciclina ácida 50mg/ml por esfregaço vigoroso por 30 segundos e grupo 5(n=10) - aplicação de 15 movimentos de raspagem por meio de ultrassom piezoelétrico com irrigação de solução polidora. Após o procedimento foram realizadas três leituras paralelas e três perpendiculares ao sentido da instrumentação utilizando rugosímetro, visando à obtenção dos valores de rugosidade superficial nos parâmetros de Ra e Rz. Os discos foram avaliados em Microscopia Eletrônica de Varredura,para a visualização da topografia superficial após os procedimentos. A análise estatística foi realizada utilizando o teste Kruskall-Wallis com um nível de significância de 5% para comparação dos valores de rugosidade superficial de cada grupo. A análise dos dados mostrou que o menor valor de rugosidade Ra foi obtido no grupo do ultrassom piezoelétrico (0.89±0.06 µm) em relação ao grupo controle (0.85±0.03 µm). O uso de tetraciclina ácida foi o tratamento que provocou maior rugosidade (0.99±0.09 µm) sendo estatisticamente diferente do grupo controle (p_0,05). Em relação ao parâmetro Rz, os resultados mostraram que o esfregaço de tetraciclina e a cureta plástica obtiveram os maiores valores de Rz (8.37±0.76 µm e 8.49±0.74µm; respectivamente) estatísticamente diferentes ao grupo controle (7.33±0.34 µm) com significância de 5%. Além disso, o uso do ultrassom piezoelétrico (7.85±0.69 µm), nos valores de Rz, não promoveu uma alteração significativa na superfície de forma a ser estatisticamente diferente do grupo controle. O estudo conclui que uso do ultrassom piezoelétrico não promoveu aumento significativo da rugosidade superficial dos discos de titânio nos parâmetros de Ra e Rz e que o jato de bicarbonato obteve valores estatísticamente semelhantes aos grupos 1, 2,4 e 5 nos dois parâmetros avaliados. O grupo da cureta plástica e esfregaço de tetraciclina ácida geraram valores estatísticamente superiores em relação ao controle e ultrassom piezoelétrico no parâmetro Rz. Todos os grupos apresentaram visualmente, a partir das fotos em microscopia eletrônica de varredura, alterações em sua superfície / Abstract: Procedures able to decontaminate the implant surface decreasing biofilm become essential to the success and longevity of implant therapy. The consequences of surface roughness generated by these procedures have been evaluated, but new proposals for decontaminating implant surfaces have been used mainly to treat periimplantite. Thus the objective was to evaluate, in vitro, the surface roughness of cylindrical titanium discs treated by plastic curette; bicarbonate jet; smear tetracycline or piezoelectric ultrasound. A total of 50 titanium discs with dimensions of 5 mm high and 5 mm wide, surfaces blasted with aluminum oxide were used. The discs were randomly divided into five groups: group 1 (n = 10)control - no treatment, group 2 (n = 10) received 15 scraping motions with plastic curette, group 3 (n = 10) application of bicarbonate jet for 30 seconds to five millimeters of distance from the surface and group 4 (n = 10) application of vigorous scraping with 50mg/ml tetracycline acid on the surface of the discs for 30 seconds and group 5 (n = 10) application of 15 scraping movements with teflon tip by ultrasonic piezoelectric with polisher irrigation solution. After treatment, three parallel and three perpendicular readings were taken to the direction of the instrumentation using a rugosimeter in order to obtain surface roughness parameters Ra which represents the arithmetic mean of the absolute values of all deviations from the surface in relation to the median in the area of sampling, and Rz which represents the average between the absolute height of the Five highest peaks and the absolute values of the 5 deepest valleys exist in the length of sampling. Furthermore, the discs were evaluated in scanning electron microscopy, an increase of 100X and 1000X, to visualize the surface topography after the procedures. Statistical analysis was performed using the Kruskal-Wallis test with a significance level of 5% compared to the values of surface roughness of each group. The lowest roughness Ra was obtained in the group of piezoelectric ultrasound (0.89 ± 0.06 µm) compared to control (0.85 ± 0.03 µm). The use of tetracycline acid was the treatment which increased the roughness (0.99 ± 0.09 µm) was statistically different from the control group (p _ 0.05). Regarding the parameter Rz, the results showed that the smear of tetracycline and plastic curette had the highest values of Rz (8.37±0.76 µm e 8.49±0.74µm, respectively) statistically different to control group (7.33 ± 0.34 µm) with significance 5%. Moreover, as the values of Ra, the use of piezoelectric ultrasound (7.85 ± 0.69 µm), the values of Rz, did not cause a significant change in the surface so as to be statistically different in the control group. The study concludes that use of piezoelectric ultrasound did not cause significant increase in surface roughness of titanium discs in the parameters of Ra and Rz. The bicarbonate jet obtained values statistically similar to other groups in both parameters .The group of plastic curette and smear tetracycline acid generated values statistically different from the control and ultrasound in piezoelectric parameter Rz. All groups presented visually, from the pictures on scanning electron microscopy, changes on its surface / Mestrado / Periodontia / Mestre em Clínica Odontológica

Orientador: Frab Norberto Boscolo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-06T22:46:39Z (GMT). No. of bitstreams: 1 Viero_FlavioLuiz_D.pdf: 553886 bytes, checksum: 6455fb7d1e46ecd9328257967d685d33 (MD5) Previous issue date: 2006 / Resumo: O objetivo neste estudo foi avaliar o efeito de diferentes doses de radiação X produzida a partir do Cobalto -60, em dois tipos de materiais odontológicos: o compósito Filtek TM A 110 3M, utilizado para restauração d e dentes anteriores; e o compósito condensável SureFilTM indicado para restauração cB dentes posteriores. Foram confeccionados 70 corpos de prova, dos quais 25 foram destinados ao teste de dureza Knoop e 50 ao teste de rugosidade de superfície. Depois de confeccionados, os corpos de prova foram acondicionados em caixas de acrílico e submersos em água destilada por um período de 24 horas, tendo com finalidade obter-se a estabilização química dos materiais. Após esse período, foram submetidos ao teste de Microdureza e de rugosidade de superfície. Obtidas essas medidas, os corpos de prova foram submetidos à irradiação, com as seguintes doses: 0,25Gy; 0,50Gy; 0,75Gy; 1Gy. Passadas 24 horas da irradiação, os mesmos 25 corpos de prova foram novamente submetidos ao teste de microdureza e os mesmos 50 éD teste de rugosidade. Logo após a realização do teste de rugosidade, os 50 corpos de prova foram submetidos à abrasão, sendo a seguir submersos em água destilada, permanecendo por 24 horas. Após esse período, um terceiro teste de rugosidade de superfície foi realizado nesses corpos de prova. De posse das medidas obtidas e após estas serem submetidas à análise estatística - Teste Tukey e o teste T pareado, observou-se que os tipos de compósitos irradiados apresentaram uma redução estatisticamente significante, nos valores de dureza Knoop, quando comparados ao material não irradiado; entretanto não foi observada diferença significante entre os grupos irradiados. Quando avaliada a rugosidade, observou-se que não houve diferença entre o grupo controle e o irradiado; entretanto houve diferença estatisticamente significante, dentro de cada grupo, antes e após os corpos de prova terem sido submetidos à abrasão. Conclui-se que, portanto, que a irradiação influenciou a dureza Knoop, mas não interferiu na rugosidade dos dois compósitos avaliados / Abstract: The aim of the present study was to evaluate the effects of different )f radiation doses produced by cobalt-60 teletherapy unit on two types of restorative dental materials: 3M Filtek TM A 110 used for forward teeth restorations and condensable SureFilTM used for back teeth restorations. Seventy five specimens were fabricated, 25 were submitted to Knoop hardness test and 50 to surface roughness. Next, the samples were immersed in distilled water in an acrylic support for chemical stabilization for 24 hours, and evaluated before irradiation test. Afterwards the samples were submitted to microhardness test and to surface roughness. Subsequently, samples were irradiated with single doses of 0,25Gy; O,50Gy; 0,75Gy; 1Gy. Twenty four hours after irradiation, the same samples were evaluated considering both tests - roughness and microhardness. After these procedures, the 50 samples used for the roughness surface evaluation were submitted to abrasion and stored in distilled water for 24 hours. After this period, the roughness surface were again analyzed. Data were submitted to Tukey test and to paired t-test, and it was observed that the two irradiated composites had a statistically significant reduction in Knoop hardness values when compared to non­irradiated composites adversely, no statically significant differences were found among the irradiated groups. Regarding surface roughness, no statistically significant difference was observed in the comparisons between the control group and irradiated group, however statistically significant differences were found inside each group, before and after the samples have been submitted to abrasion. It was concluded that the x-irradiation influenced the Knoop hardness, therefore it did not interfere on the surface roughness of the two restorative composite evaluated. / Doutorado / Radiologia Odontologica / Doutor em Radiologia Odontológica