Thesis (M.S.)--Brigham Young University. Dept. of Mechanical Engineering, 2005. / Includes bibliographical references (p. 63-65).

Thesis (M.S. in computer engineering)--Washington State University, December 2005. / Includes bibliographical references (p. 60-61).

Thesis (M.S.)--Brigham Young University. Dept. of Mechanical Engineering, 2005. / Includes bibliographical references (p. 91-94).

Dissertation (Ph.D.)--Worcester Polytechnic Institute. / Keywords: axiomatic design, case-based reasoning, fixture design, retrieval-by-adaptabilty. Includes bibliographical references (p.273-281).

Thesis (M. S.)--Architecture, Georgia Institute of Technology, 2007. / Athanassios Economou, Committee Member ; Chuck Eastman, Committee Member ; Russell Gentry, Committee Chair.

Orientadores: Marcelo Giannini, Pascal Magne / Tese (Doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-21T22:55:10Z (GMT). No. of bitstreams: 1 Carvalho_AdrianaOliveira_D.pdf: 96375930 bytes, checksum: 98085bf2a4f1941f9510f1ba4c7d0a85 (MD5) Previous issue date: 2013 / Resumo: Objetivos: Comparar a resistência à fadiga (RFAD) e à fratura (RFRA), o modo de falha e o desgaste do antagonista em contato com os diferentes designs de coroas CAD/CAM utilizadas para restaurar molares tratados endodonticamente/TE ou não, fabricadas em cerâmica feldspática/FEL, dissilicato de lítio/DL ou resina nano cerâmica/RNC e fixadas com cimento resinoso auto-adesivo. Materiais e Métodos: Para os capítulos um e dois, 90 molares foram preparados e restaurados com coroas com espessura de 1,5mm ou 0,7mm respectivamente, em FEL, DL ou RNC. Para os capítulos três e quatro, outros 90 molares tiveram a porção coronária removida (nível da junção cemento-esmalte), foram TE e restaurados utilizando três diferentes designs de núcleo de preenchimento em resina composta/NPRC (4-mm de altura, 2-mm ou sem núcleo de preenchimento/endocrown) associados a coroas em RNC ou DL respectivamente. Para o capítulo cinco, grupos dos capítulos um (RNC/1,5mm e DL/1,5mm), três (NPRC de 4-mm de altura/RNC) e quatro (NPRC de 4-mm de altura/DL) foram combinados. Todas as coroas do estudo foram confeccionadas pelo sistema CAD/CAM Cerec 3 e cimentadas com o cimento RelyX Unicem II Automix. As coroas em FEL e DL foram previamente condicionadas com ácido fluorídrico e silanizadas. As coroas em RNC, assim como os dentes preparados foram apenas jateados. Todas as restaurações foram submetidas ao teste de RFAD com um carregamento cíclico isométrico aplicado por uma esfera de resina composta. O carregamento começou com cargas de 200N (5.000x) seguidos por estágios de 400, 600, 800, 1000, 1200 e 1400N a um máximo de 30.000 ciclos cada. Os espécimes foram submetidos ao carregamento até a fratura ou por no máximo 185.000 ciclos. Os espécimes que resistiram a todos os ciclos foram novamente testados axialmente até a falha ou até uma carga máxima de 4.500N. Os espécimes foram classificados quanto ao modo de falha em: catastrófica, possivelmente reparável e reparável. Os grupos foram comparados utilizando uma análise de sobrevida para o teste de RFAD e t-test ou ANOVA para o teste de RFRA. Comparações Post hoc também foram utilizadas para comparar os diferentes grupos. Resultados: A taxa de sobrevida das coroas sobre os molares não TE foram: 80% (RNC/1,5mm), 6,6% (RNC/0,7mm), 93,3% (DL/1,5mm), 13,2% (DL/0,7mm), 6,6% (FEL/1,5mm) e 0% (FEL/0,7mm). A RFRA das coroas com 1,5mm de espessura foi: 3122N-RNC, 3237N-DL e 2500N-FEL. As coroas cimentadas sobre molares TE tiveram taxa de sobrevida e RFRA respectivamente de: 53%/2969N (RNC-4mm de altura), 100%/3181N (DL-4mm de altura), 87%/2794N (RNC-2mm de altura), 93%/3759N (DL-2mm de altura), 87%/2606N (RNC-endocrown) e 100%/3265N (DL-endocrown). No teste de RFAD houve falha catastrófica apenas para as coroas confeccionadas em RNC-4mm. Após o teste de RFRA todos os espécimes falharam catastroficamente. As coroas em RNC induziram menor desgaste aparente ao antagonista. Conclusão: Apenas as coroas FEL-0,7mm não sobreviveram além da máxima força mastigatória humana. Para os dentes não TE, as coroas em DL e RNC com espessuras de 1,5mm tiveram o melhor desempenho mecânico. Para os molares TE, uma maior carga para fratura foi requerida com o uso de coroas em DL-2mm. O tratamento endodontico não teve influência sobre a RFAD de molares restaurados com coroas CAD/CAM de DL, mas diminuiu a performance das RNC / Abstract: Objectives: To evaluate the fatigue resistance, load-to-failure, failure mode and antagonistic wear in contact with different designs of full CAD/CAM crowns made of feldspathic ceramic/FEL, lithium disilicate/LD or resin nano ceramic/RNC. These prosthetic materials were used to restore endodontic treated molars or not, using a simplified cementation process. Materials and Methods: Chapters One and Two used 90 molars, which had a standardization of full crown preparation and teeth were restored using crown made of FEL, LD and RNC with thickness of 1.5mm or 0.7mm, respectively. Chapters Three and Four used 90 molars decoronated at the level of CEJ, endodontically-treated and restored using three different Filtek Z100 adhesive core build-ups designs (4-mm-build-up; 2-mm-build-up; and no buildup/ endocrown preparation) combined to crowns made of RNC and LD, respectively. For Chapter Five, groups of Chapters One (RNC/1,5mm and LD/1,5mm), Three (4-mm-build-up/RNC) and Four (4-mm-build-up/LD) were combined. All molars were restored using the Cerec 3 CAD/CAM system and cemented with RelyX Unicem II Automix cement. FEL and LD restorations were conditioned by hydrofluoric acid etching and silanated. RNC restorations as well as all preparations were treated only with airborne-particle abrasion. All restorations were submitted to cyclic isometric loading applied through a composite resin hemi-sphere. The cyclic loading started with a load of 200N (x5000 cycles), followed by stages of 400, 600, 800, 1000, 1200, and 1400N at a maximum of 30,000 cycles each. Specimens were loaded until failure or for a maximum of 185,000 cycles. Survived specimens were axially loaded until failure or to a maximum load of 4,500N. After load tests, the specimens were analyzed for the failure mode: "catastrophic" tooth/root failure, "possibly reparable" failure and "reparable" failure. Groups were compared using the life table survival analysis (fatigue test) and the t-test, one-way or two-way ANOVA for the survived samples loaded to failure. Pairwise post hoc comparisons were used to compare the different groups. Results: The survival rates for the vital teeth were: 80% (RNC - 1.5mm), 6.6% (RNC - 0.7mm), 93.3% (LD - 1.5mm), 13.2% (LD - 0.7mm), 6.6% (FEL - 1.5mm) and 0% (FEL - 0.7mm). Post-fatigue load-to-failure for 1.5mm crowns ranged between 3122N (RNC), 3237N (LD) and 2500N (FEL). The survival rate and post-fatigue load to failure for non-vital teeth were 53% / 2969N (4mm - RNC), 100% / 3181N (4mm - DL), 87% / 2794N (2mm - RNC), 93% / 3759N (2mm - DL), 87% / 2606N (endocrown - RNC) e 100% / 3265N (endocrown - LD), respectively. There were only catastrophic failures for 4mm-build-up RNC during the fatigue test. All of specimens in the load-to-failure test exhibited non-restorable catastrophic fractures. Crowns made of RNC seemed to generate the least amount of antagonistic wear. Conclusions: FEL crowns with 0.7mm of thickness didn't survive beyond the maximum masticatory forces. RNC and LD crowns with 1.5mm thick had the best performance on vital teeth. LD crowns combined with short build-ups (2mm) were associated to highest loads to failure. Endodontic treatment did not influence the fatigue resistance of molars restored with LD CAD/CAM complete crowns but decreased the performance of RNC crowns / Doutorado / Materiais Dentarios / Doutora em Materiais Dentários

M.Ing. / Please refer to full text to view abstract

M.Sc. / The technique known as "Rapid Prototyping" constitutes a technology that is already saving large corporations time and money in respect of prototyping. Currently, Rapid Prototyping machines are, however, still expensive to purchase and maintain. In order to allow more people to make use of Rapid Prototyping machines, certain businesses are specialising in rendering a Rapid Prototyping service. Rapid Prototyping service bureaux render such service by selling machine time. To allow people to make use of the service, designs are submitted across a distance by means of telemanufacturing. To enable a wide variety of users to avail themselves of this service, certain checks and balances must, however, be put into place. These checks and balances must test whether or not a valid job has been submitted, and if so, the submitter has to be assisted in deciding upon settings. In order to submit a job from anywhere in the world, the Internet is harnassed for telemanufacturing. Once remote submission has been made safe and convenient, more businesses and individuals could derive benefit from Rapid Prototyping. This dissertation has, therefore, been undertaken to identify the prerequisites for Rapid Prototyping. Once a job has been submitted, it has to be checked for errors and the user has to be advised on building types and recommendations. For this, an agent is used. In this way, problems are prevented, should faulty jobs be sent to a Rapid Prototyping machine. Once a job has been submitted, it is scheduled by a queue manager in order to maximise machine usage. Rapid Prototyping has the potential in future to become as commonplace as printers. In terms of this technology, a design would, therefore, be printed in three dimensions for instant verification by the user. The very advantage of being able to hold a new product in one's hands is self-evident. The technology that is being developed today will, therefore, be successfully used in future scenarios.

An Apple microcomputer and a three axis milling machine are the basis for a CAD/CAM system with the capability of drilling and contour milling operations. The milling machine axes are driven by three stepper motors under the control of the Apple microcomputer and the ISAAC data acquisition module. An interactive part design program using high resolution color graphics has been developed. It employs lines, circles and points to define the geometry for the part. The design is entered at the CRT and stored as a CAM database on the user disc. Once the design is complete it is postprocessed and the milling machine and the Apple are connected through the ISAAC module. The raw part is set up on the mill and control of contouring is by the Apple microcomputer. The software has been designed to operate very similar to the EZCAM interactive part design software available on the Bridgeport CNC Mark II Series milling machine. It has been developed using Applesoft BASIC language and the 6502 Assembly language.

This thesis introduces GENMOD, a collection of subroutines which allow automatic geometric modeling of 3-D models for spatial links or linkages given a minimum amount of information as input. The subroutines utilize the CADCD (CADAM, Inc.) geometry interface software to enter 3-D data directly into the CAD/CAM database. Wire-frame and surface models are produced. Input is accepted from user created files with a standardized format allowing the GENMOD subroutines to be implemented regardless of the synthesis and analysis routines used. The realistic visualization of a mechanism during the synthesis and analysis process can help the mechanism designer to eliminate unacceptable linkage configurations in the early design stages thereby saving time and money. A complete description of the subroutines is provided in addition to sample graphic output. / M.S.