Submitted by ISABELA LIMA (belapcl@yahoo.com.br) on 2016-10-11T14:46:13Z No. of bitstreams: 1 IsabelaPCL_Tese.pdf: 5559543 bytes, checksum: afab7eefca4599c09d42b48184a649c0 (MD5) / Approved for entry into archive by clediane guedes (clediane@bczm.ufrn.br) on 2016-10-11T14:47:24Z (GMT) No. of bitstreams: 1 IsabelaPCL_Tese.pdf: 5559543 bytes, checksum: afab7eefca4599c09d42b48184a649c0 (MD5) / Made available in DSpace on 2016-10-11T14:47:24Z (GMT). No. of bitstreams: 1 IsabelaPCL_Tese.pdf: 5559543 bytes, checksum: afab7eefca4599c09d42b48184a649c0 (MD5) Previous issue date: 2005 / Buscou-se com esta pesquisa estabelecer a influ?ncia da diatomita, uma rocha sedimentar, rica em s?lica, encontrada em abund?ncia nas bacias rasas nordestinas, sobre uma resina odontol?gica comercial Z250TM quando agregada ? mesma. Para tal foi necess?ria a caracteriza??o dos precursores: 1)resina comercial atrav?s de calorimetria explorat?ria diferencial (DSC), termogravimetria (TG), espectroscopia na regi?o infra-vermelho (IV) e fluoresc?ncia de raios X e 2)diatomita atrav?s de difra??o de raios X (DRX), calorimetria explorat?ria diferencial (DSC), termogravimetria (TG), espectroscopia na regi?o do infra-vermelho (IV), an?lise t?rmica diferencial (DTA), an?lise qu?mica, an?lise de ?rea superficial pelo m?todo BET, an?lise do tamanho de part?culas. Deu-se ent?o a confec??o das amostras controle (material de partida, ou seja, resina comercial Z250) e das amostras teste (material de partida acrescido de diatomita). Realizou-se tamb?m ensaios mec?nicos (resist?ncia ? compress?o, resist?ncia ? tra??o diametral resist?ncia ao desgaste em micr?metros, avalia??o da microdureza e da rugosidade superficial) e uma nova caracteriza??o das amostras controle e teste (termogravimetria (TG), an?lise t?rmica diferencial (DTA), difra??o de raios X (DRX), microscopia ?tica (MO) e microscopia eletr?nica de varredura (MEV). Surgiu ent?o como produto deste trabalho, um material restaurador odontol?gico in?dito, com todas propriedades mec?nicas superiores ?s do material de partida, de custo acess?vel por utilizar mat?ria prima regional, sintetizado e caracterizado atrav?s da interrela??o dos conhecimentos da Odontologia e da Engenharia de Materiais, e que se presta tanto para ?reas est?ticas, como para ?reas que demandem maiores esfor?os mastigat?rios. / The aim of this work was established the diatomite effect, being it a sedimentary stone, with a lot of silic, founded at rivers margins of North East from Brasil, about a commercial odontological composite resin Z250TM after added both. The precursors characterization carried out by: 1)commercial odontological composite resin: differential exploratory calorimetry (DSC), termogravimetric analysis (TG), spectroscopy in the infra red region (FTIR) and X-ray fluorescence e; 2)diatomite: X-ray diffraction (DRX), differential exploratory calorimetry (DSC), termogravimetric analysis (TG), spectroscopy in the infra red region (FTIR), differential thermal analysis (DTA), chemical analysis, superficial area analysis (BET), particle size analysis. There was beginning the control samples prepare (initial material or commercial odontological composite resin Z250) and tests samples (initial material added diatomite). There was made too mechanical evaluations (resistance to compression, diametrical tension, abrasion, micro hardness and its superficial roughness) and another samples control and tests characterization by termogravimetric analysis (TG), differential thermal analysis (DTA), X-ray diffraction (DRX), optical microscopy (MO) and scanning electronic microscopy(MEV). The final product from this search was a unpublished odontological restorative material, with all mechanical properties better than initial material, minus expensive in order to use regional materia prima, made and caracterizated by the interrelation of know ledges from Odontology and Materials Tecnology. This new material may be used both aesthetical areas and great mastication efforts areas.

Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-26T14:53:16Z No. of bitstreams: 1 TES_DIMAS_JOAO_RODRIGUES_NETO_PARCIAL.pdf: 405454 bytes, checksum: d48967a61777e3e773d5a2112997ee13 (MD5) / Made available in DSpace on 2017-06-26T14:53:16Z (GMT). No. of bitstreams: 1 TES_DIMAS_JOAO_RODRIGUES_NETO_PARCIAL.pdf: 405454 bytes, checksum: d48967a61777e3e773d5a2112997ee13 (MD5) Previous issue date: 2017-01-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / For a satisfactory clinical performance, pre-fabricated Co-Cr cylinders must have metallurgical compatibility to Co-Cr based cast alloys. A uniform interface with adequate union and resistance, with absence of interfacial reaction and porosities must be obtained. The present in vitro study aimed to evaluate the metallurgical compatibility at the interface between pre-fabricated Co-Cr cylinders and alloys for Co-Cr compound casting applying different casting techniques. In manuscript 2 the metallurgical compatibility and the interface between implant and alloy cylinders were evaluated for Co-Cr casting with different melting temperatures. Methodology: Three pre-fabricated Co-Cr prosthetic implant cylinders (Neodent, Pi-Br?nemark, Dentium) were subjected to casting with Co-Cr alloy using different casting techniques (Flame Torch, Induction / Centrifugation, Induction / Vacuum). Optical microscopy and Scanning Electron Microscopy (SEM) were used to characterize the obtained microstructures. The elementary composition of the cylinders and diffusion characteristics in the interfacial region between molten alloy and cylinder were determined by dispersive energy spectroscopy (EDS). Vickers microhardness was measured at interface, cylinder and cast alloy. The ANOVA and Tukey test were used to evaluate microhardness values. In the manuscript 2 cylinders based on Co-Cr were overfused with alloys with different melting temperatures and all microstructural analysis and microhardness tests were performed. Results: In the manuscript 1 a union between pre-fabricated cylinders and Co-Cr based alloys was observed microstructurally. An ideal interface was obtained with absence of interfacial reaction or significant porosities with the casting with the induction techniques (centrifugation and vacuum), but excess of porosities and failures were observed with the Torch casting technique. In manuscript 2 a microstructural bond was observed between the alloys and the cylinder, evidencing that both high melt alloy and low melt alloy presented compatibility with the Co-Cr cylinder. Microhardness values, both in manuscript 1 and in manuscript 2 also proved to form a satisfactory interface. Conclusions: It was concluded from manuscript 1 and 2 that both high and low melt temperature Co-Cr have metallurgical compatibility to pre-fabricated Co-Cr cylinders, showing an ideal interface. However, the technique of casting applied is relevant, and the torch technique has been shown to be less indicated due to the lack of standardization of the obtained results. / Para um bom desempenho clinico, cilindros de pilares pr? fabricados de Co-Cr devem apresentar compatibilidade metal?rgica a ligas de sobrefundi??o a base de Co-Cr. Uma interface uniforme com adequada uni?o e resist?ncia, com aus?ncia de rea??o interfacial e porosidades devem ser obtidas. O presente estudo, in vitro, objetivou atrav?s do manuscrito 1 avaliar a compatibilidade metal?rgica na interface entre cilindros pr? fabricados de Co-Cr e ligas para sobrefundi??o de Co-Cr com diferentes t?cnicas de fundi??o. No manuscrito 2, foi avaliado a compatibilidade metal?rgica e a interface entre cilindro de implante e ligas para sobrefundi??o de Co-Cr com diferentes temperaturas de fus?o. Metodologia: Tr?s cilindros pr?-fabricados para pr?tese sobre implantes em Co-Cr (Neodent, Pi-Br?nemark, Dentium) foram sorefundidos com liga de Co-Cr com diferentes t?cnicas de fundi??o (Ma?arico, Indu??o/centrifuga??o, Indu??o/v?cuo). Microscopia ?ptica e Microscopia eletr?nica de varredura (MEV) foram usadas para caracteriza??o das microestruturas. A composi??o elemental dos cilindros e caracter?sticas de difus?o na regi?o interfacial entre liga fundida e cilindro foram determinadas atrav?s de espectroscopia por energia dispersiva (EDS). Microdureza de Vickers foi aplicada na interface, cilindro e liga fundida. Foi aplicado o teste de ANOVA e Tukey para avalia??o dos valores microdureza. No manuscrito 2, cilindros a base de Co-Cr foram sobrefundidos com ligas com diferentes temperaturas de fus?o e foi realizada toda analise microestrutural e testes de microdureza. Resultados: No manuscrito 1 observou-se microestruturalmente uma uni?o entre cilindros pr? fabricados e ligas a base de Co-Cr. Foi obtida uma interface ideal com aus?ncia de rea??o interfacial ou porosidades significantes com a fundi??o com as t?cnicas por indu??o (centrifuga??o e v?cuo), por?m excesso de porosidades e falhas foram observados com a t?cnica de fundi??o ? ma?arico. No manuscrito 2 observou-se uma uni?o microestrutural entre as ligas e o cilindro avaliado, evidenciando que tanto liga de alta fus?o, quanto de baixa fus?o apresentam compatibilidade ao cilindro de Co-Cr. Valores de microdureza, tanto no manuscrito 1 como no manuscrito 2 tamb?m comprovaram a forma??o de uma interface satisfat?ria. Conclus?es: Concluiu-se atrav?s do manuscrito 1 e 2 que ligas de alta e baixa temperatura de fus?o a base de Co-Cr apresentam compatibilidade metalurgica a cilindros pr? fabricados de Co-Cr apresentando uma interface ideal. Por?m, a t?cnica de fundi??o aplicada ? relevante, sendo que a t?cnica ? ma?arico se mostra a menos indicada devido a falta de padroniza??o dos resultados obtidos.

Made available in DSpace on 2014-12-17T14:13:57Z (GMT). No. of bitstreams: 1 KarlaPCA.pdf: 417680 bytes, checksum: 45816114a785f665c7781391afa90d18 (MD5) Previous issue date: 2005-12-05 / The present research carried out from three national dentistry magazines published in the period between 1990 and 2004, has as a goal to analyze how bioethics has been approached in this area, not only identifying the main concerns and tendencies, but also aiming to learn how this knowledge is produced and divulged in the dentistry circuit. We have articulated a quantitative-qualitative approach, studying 2995 articles. The articles were selected and assorted in twenty thematic categories, through their titles and key words. The analysis of the empiric material shows that, although there is a growth tendency of this discussion, little has been published about this theme (1,9%). Besides, it seems that there is an arrhythmia between the present bioethic approach in dentistry and the present life demands, where the deontology and legalist focuses are predominant, seeming to correspond to the inner aspects of the profession alone. In spite of this, through the qualitative approach it was possible to identify ways to build a more complex and integral odontological formation and practice. Within the conclusions, we still point out, that, this investigation, even face to its limitations, seems to offer subsidies for reflection and further studies about the theme, working as a parameter to keep up with the evolution of the bioethic thinking in the Odontology / A presente pesquisa realizada a partir de tr?s revistas nacionais de odontologia publicadas no per?odo de 1990 a 2004, tem como objetivo analisar como a (bio)?tica vem sendo abordada nesta ?rea, n?o s? identificando as principais preocupa??es e tend?ncias, mas tamb?m visando apreender como esse conhecimento ? produzido e divulgado no ?mbito odontol?gico. Articulamos uma abordagem quantitativa/qualitativa, estudando 2995 artigos. A an?lise do material emp?rico revela que, apesar de existir uma tend?ncia de crescimento dessa discuss?o, pouco tem sido publicado sobre o tema (1,9%). Al?m do mais, parece haver um descompasso entre a atual abordagem da (bio)?tica em odontologia e as atuais exig?ncias da vida, onde predominam os enfoques deontol?gico e legalista, parecendo corresponder apenas aos aspectos internos da profiss?o. Apesar disso, atrav?s da abordagem qualitativa foi poss?vel identificar caminhos para a constru??o de uma forma??o e pr?tica odontol?gicas mais complexas e integrais. Dentre as conclus?es, apontamos, ainda, que, esta investiga??o, mesmo diante de suas limita??es, parece oferecer subs?dios para reflex?o e posteriores estudos sobre o tema, servindo de par?metro para acompanhar a evolu??o do pensar (bio)?tico na odontologia

Made available in DSpace on 2014-12-17T15:31:00Z (GMT). No. of bitstreams: 1 EwertonWGB.pdf: 661743 bytes, checksum: 00ecd30c8cac5a4445285f2bdf4508ad (MD5) Previous issue date: 2006-05-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The dental documentation or handbook is a collection of documents produced by the professional with diagnostic and therapeutical purpose where the inherent information to the buccal and general health of patients are registered. The register and proper filling of these documents, taking care of the ethical and legal requirements, provide to the dentist the possibility to contribute with justice in cases of human identification and makes of these documents an essential element of evidence in the ethical processes, administrative, civil and criminal against the dentists. Ahead of this fact, understanding such requirements and the importance of the dentist to register himself adequately, this research verified the knowledge of Natal (RN) City s dentists with relation to the elaboration of the dental handbook, investigating the concepts and the importance attributed to the handbook, identifying the documents more used and filed by these professionals, besides inquiring the legal value of filed documents and the filling time of these ones. The sample was constituted by 124 dentists, who had answered a questionnaire, after having been randomly selected ITom a list of professionals subscribed in the Dentistry Local Council/RN Section. The analysis of the results showed that majority of the participant cit?zens (52,3%) confers to the dental documentation the clinical importance, followed by the legal and forensic-dentistry importance; 59,3% of the searched professionals do not distinguish satisfactorily or they do not observe differences between the dental handbook and the clinical filing card, the X-rays, the dental certificates, the prescriptions, the directions and the receipts; between the documents of common use to cl?nical and specialist ones, the contract of rendering of services and term of ITee and cleared up consent are the documents less used by the professionals. It was still verified, that only 13,1% of the sample register the signature of the patients in the clinical filing card, making it more credibility to be presented in judgement. In the same way, copies of dental certificates and prescriptions evaluated and signed by the patients are filed respectively by only 13,5% and 9,4% ofthe searched professionals and 50% ofthe sample, keep these documents filed for an indeterminate period of time, that is, these professionals have the guard of the handbook and they do not intend to disdain it, although 85,5% of the sample does not recognize the real proprietor of the handbook. It is concluded that a great part of the dentists is unaware about the importance of the dental documentation, and neglect its elaboration, leaving themselves exposed to several kinds of penalties foreseen in the legislation / A documenta??o odontol?gica ou prontu?rio odontol?gico ? uma cole??o de documentos produzidos pelo profissional, com finalidade diagn?stica e terap?utica, onde s?o registradas as informa??es inerentes ? sa?de bucal e geral dos pacientes. O registro e arquivamento correto destes documentos, atendendo as exig?ncias ?ticas e legais, proporcionam ao cirurgi?odentista a possibilidade de contribuir com a justi?a nos casos de identifica??o humana e faz destes documentos um elemento de prova essencial nos processos ?ticos, administrativos, civis e penais contra os cirurgi?es-dentistas. Diante deste fato, entendendo tais exig?ncias e a import?ncia do cirurgi?o-dentista documentar-se adequadamente, esta pesquisa verificou o conhecimento cirurgi?es-dentistas do munic?pio de Natal- RN com rela??o ? elabora??o do prontu?rio odontol?gico, investigando os conceitos e a import?ncia atribu?da ao prontu?rio, identificando os documentos mais utilizados e arquivados por estes profissionais, al?m averiguar o valor jur?dico dos documentos arquivados e o tempo de arquivamento destes. A amostra foi constitu?da por 124 cirurgi?es-dentistas, que responderam um question?rio, ap?s terem sido alocados aleatoriamente a partir de uma lista de profissionais cadastrados no Conselho Regional de Odontologia - RN. A an?lise dos resultados mostrou que maioria dos sujeitos participantes (52,3%) confere ? documenta??o odontol?gica a import?ncia cl?nica, seguida pela import?ncia jur?dica e odontolegal; 59,3% dos profissionais pesquisados n?o distinguem satisfatoriamente ou n?o observam diferen?as entre o prontu?rio odontol?gico e a ficha cl?nica; os documentos mais utilizados s?o a ficha cl?nica, as radiografias, os atestados, as receitas, os encaminhamentos e os recibos; entre os documentos de uso comum a cl?nicos e especialistas, o contrato de presta??o de servi?os e o termo de consentimento livre e esclarecido s?o os documentos menos utilizados por estes profissionais. Verificou-se, ainda, que apenas 13,1% da amostra registra a assinatura dos pacientes na ficha cl?nica, dando-lhe mais credibilidade para ser apresentada em ju?zo. Da mesma forma, c?pias de atestados e receitas avalizadas e assinadas pelos pacientes s?o arquivadas respectivamente por apenas 13,5% e 9,4 % dos profissionais pesquisados e 50% da amostra mant?m estes documentos arquivados por um tempo indeterminado, ou seja, estes profissionais t?m a guarda do prontu?rio e n?o pretendem desprez?-Io, apesar de 85,5% da amostra desconhecer o verdadeiro propriet?rio do prontu?rio. Concluiu-se que uma grande parte dos cirurgi?esdentistas desconhece a import?ncia da documenta??o odontol?gica, e negligenciam a sua elabora??o, deixando-os predispostos as v?rias penalidades previstas na legisla??o

Made available in DSpace on 2015-04-14T13:58:30Z (GMT). No. of bitstreams: 1 412506.pdf: 6158899 bytes, checksum: cf5ae318388023b15dba86f3e20e4304 (MD5) Previous issue date: 2009-04-30 / A liga de Ni-45%Ti em peso, conhecida desde a d?cada de 70 e denominada NITINOL?, apresenta excelentes caracter?sticas de resist?ncia ? corros?o, resist?ncia a fadiga, biocompatibilidade e elevadas propriedades mec?nicas. As ligas Ni-Ti apresentam recupera??o de forma (E.M.F Efeito de Mem?ria de Forma) de at? 8%, com temperatura de recupera??o variando de -50?C a +110?C, dependendo da composi??o qu?mica da liga e da microestrutura, tendo como principais aplica??es: ?reas aeroespacial, naval, nuclear, automobil?stica, utilidades dom?sticas, rob?tica, com destaque nas ?reas m?dica e odontol?gica. O objetivo do presente trabalho ? o estudo da liga Ni-Ti em rela??o ao E.M.F e compara??o de propriedades mec?nicas e estruturas por meio de an?lises metalogr?ficas (microscopia ?ptica e eletr?nica), ensaios de microdureza Vickers, difra??o de raios X e fluoresc?ncia de raios X, nas condi??es: fios comerciais e ap?s tratamentos t?rmicos de normaliza??o em diferentes temperaturas (TTx): 300?C, 500?C e 700?C. Os resultados foram correlacionados com a microestrutura resultante e as condi??es de tratamento t?rmico. Concluiu-se que de acordo com os objetivos estabelecidos e as t?cnicas de caracteriza??o e ensaios utilizados, a amostra com melhor rendimento foi ? tratada termicamente a 500?C.

Made available in DSpace on 2015-04-14T13:29:17Z (GMT). No. of bitstreams: 1 400750.pdf: 3101518 bytes, checksum: e6af479d16d5fa9302f205b0fc307429 (MD5) Previous issue date: 2008-01-16 / Os sistemas de planejamento, baseados em imagens tomogr?ficas digitais, permitem ao profissional selecionar os locais mais adequados para a coloca??o de implantes dent?rios, levando em considera??o as caracter?sticas anat?micas espec?ficas de pacientes e a estrutura ?ssea das ?reas de interesse. A transfer?ncia do planejamento de implantes realizado em computador para o campo cir?rgico, apesar de muito importante, permanece como um procedimento dif?cil de ser executado com precis?o. Nesta pesquisa, realizou-se um estudo comparativo entre posi??o e angula??o planejadas para implantes dent?rios e os resultados obtidos ap?s a execu??o dos procedimentos. Para isso, utilizou-se 11 mand?bulas humanas secas, levando-se em considera??o a precis?o do planejamento virtual realizado. A sobreposi??o das imagens dos implantes dent?rios planejados sobre aquelas do que foi executado, recebeu processamento computadorizado e, ent?o, avalia??o quanto ?s dist?ncias aferidas e ?s angula??es em rela??o ao longo-eixo destes implantes. Ao se aplicar o teste t de Student para comparar as amostras com um valor de refer?ncia zero, verificaram-se diferen?as estatisticamente significativas para as medidas lineares e angulares analisadas, indicando a necessidade de estudos complementares que verifiquem a aplicabilidade desta nova rotina t?cnica na pr?tica cl?nica de Implantodontia.

Made available in DSpace on 2014-12-17T14:06:54Z (GMT). No. of bitstreams: 1 ClaudiaAMS_DISSERT.pdf: 2577371 bytes, checksum: 741bbb91aaccd5dd4b233f1b8017a831 (MD5) Previous issue date: 2010-03-29 / The continuous advances in ceramic systems for crowns and bridges infrastructure getting researchers and manufacturers looking for a material that has good mechanical properties and aesthetic. The purpose of this study was to verify in which composition and sintering temperature the ceramic system for infrastructure composed of alumina and zirconia would have the best mechanical properties. With this objective we made in UFRN laboratories 45 test bodies in the form of rectangular bars with the following dimensions: 30mm x 8mm x 3mm, where we separated by the sintering temperature: 1200?C, 1300?C and 1400?C, and by comp osition: 33% Zirconia + 67% Alumina; 50% Zirconia + 50% Alumina and 25% Zirconia + 75% Alumina, these test bodies were not infiltrated with glass. Also, were made nine test bodies by a technical from a laboratory with a commercial ceramic system: in the Ceram Zirc?nia (Vita - Zahnfabrik) with the following dimensions: 20mm x 10mm x 0.5mm, these test bodies following all recommendations of the manufacturer and were infiltrated with glass. Were realized optical and electronic microscopy analyses, hardness testing, resistance to bending in three points, porosity and bulk density. After analysis of the results we verified that with the increasing of sintering temperature, increased the value of resistance to bending, but with the same temperature there was no significant difference between the different compositions, samples made with the commercial ceramic that were infiltrated, presented a resistance to bending six times greater than the samples sintered to 1400?C and which have not been infiltra ted. There was no significant difference between the values of apparent porosity for the samples made in UFRN laboratories, but the samples of commercial ceramic obtained 0% in porosity apparent value. In tests of Rockwell Hardness there is an increase in the value of Hardness, with the increase of sintering temperature for the samples not infiltrated. Samples infiltrated showed similar values as the samples sintered in 1400?C. There was no significant difference between the values of apparent density among samples manufactured in UFRN laboratories and samples made with a commercial ceramic / Os avan?os constantes dos sistemas cer?micos para infra-estruturas de coroas e pontes fazem com que os pesquisadores e fabricantes busquem um material que tenha boas propriedades mec?nicas e est?ticas. O intuito deste trabalho foi verificar em qual composi??o e temperatura de sinteriza??o o sistema cer?mico a base de alumina e zirc?nia para infra-estrutura teria as melhores propriedades mec?nicas. Com este objetivo confeccionamos nos laborat?rios da UFRN 45 corpos-e-prova em forma de barras retangulares com as seguintes dimens?es: 30mm x 8mm x 3mm, onde os separamos por temperatura de sinteriza??o: 1200?C, 1300?C e 1400?C; e por composi??o: 33% Zirc?nia + 67% Alumina; 50% Zirc?nia + 50% Alumina e 25% Zirc?nia + 75% Alumina, estes corpos-de-prova n?o foram infiltrados com vidro. Foram confeccionados ainda nove corpos- e-prova por um t?cnico de laborat?rio com um sistema cer?mico comercial o In Ceram Zirc?nia (Vita Zahnfabrik) com as seguintes dimens?es: 20mm x 10mm x 0,5mm, estes corpos-de-prova seguiram todas as recomenda??es do fabricante e foram infiltrados com vidro. Foram realizadas an?lises por microscopia ?tica e eletr?nica, ensaios de dureza, de resist?ncia ? flex?o em tr?s pontos, porosidade e densidade aparente. Ap?s a an?lise dos resultados verificamos que com o aumento da temperatura de sinteriza??o, aumentamos o valor da resist?ncia ? flex?o, sendo que dentro da mesma temperatura n?o houve diferen?a significante entre as diferentes composi??es, as amostras confeccionadas com a cer?mica comercial e que foram infiltradas apresentaram uma resist?ncia ? flex?o seis vezes maior que as amostras sinterizadas ? 1400?C e que n?o foram infiltradas. N?o houve diferen?a significante entre os valores da porosidade aparente para as amostras confeccionadas nos laborat?rios da UFRN, j? as amostras da cer?mica comercial obtiveram um valor de 0% de porosidade aparente. Nos ensaios de Dureza Rockwell verifica-se um aumento no valor da Dureza, com o aumento da temperatura de sinteriza??o das amostras n?o infiltradas. As amostras infiltradas apresentaram valores similares aos das amostras sinterizadas ? 1400?C. N?o houve diferen?a significante entre os valores de densidade aparente entre as amostras confeccionadas nos laborat?rios da UFRN e as amostras confeccionadas com a cer?mica comercial

Made available in DSpace on 2014-12-17T14:06:55Z (GMT). No. of bitstreams: 1 LarissaBMG_DISSERT.pdf: 3976426 bytes, checksum: c7a9c5605953e13f9ff21ef4453a3aef (MD5) Previous issue date: 2010-06-02 / Composite resins have been subjected to structural modifications aiming at improved optical and mechanical properties. The present study consisted in an in vitro evaluation of the staining behavior of two nanohybrid resins (NH1 and NH2), a nanoparticulated resin (NP) and a microhybrid resin (MH). Samples of these materials were prepared and immersed in commonly ingested drinks, i.e., coffee, red wine and acai berry for periods of time varying from 1 to 60 days. Cylindrical samples of each resin were shaped using a metallic die and polymerized during 30 s both on the bottom and top of its disk. All samples were polished and immersed in the staining solutions. After 24 hours, three samples of each resin immersed in each solution were removed and placed in a spectrofotome ter for analysis. To that end, the samples were previously diluted in HCl at 50%. Tukey tests were carried out in the statistical analysis of the results. The results revealed that there was a clear difference in the staining behavior of each material. The nanoparticulated resin did not show better color stability compared to the microhybrid resin. Moreover, all resins stained with time. The degree of staining decreased in the sequence nanoparticulated, microhybrid, nanohybrid MH2 and MH1. Wine was the most aggressive drink followed by coffee and acai berry. SEM and image analysis revealed significant porosity on the surface of MH resin and relatively large pores on a NP sample. The NH2 resin was characterized by homogeneous dispersion of particles and limited porosity. Finally, the NH1 resin depicted the lowest porosity level. The results revealed that staining is likely related to the concentration of inorganic pa rticles and surface porosity / Nos ?ltimos anos, as resinas compostas t?m passado por uma s?rie de modifica??es estruturais na busca de melhores propriedades ?pticas e mec?nicas. O presente estudo avaliou in vitro o grau de manchamento em duas resinas nanoh?bridas (NH1 e NH2), uma nanoparticulada (NP) e uma microh?brida (MH), quando expostas ?s solu??es corantes, caf?, vinho tinto e a?a?, nos per?odos de 1, 7, 30 e 60 dias. Foram confeccionadas 192 amostras atrav?s de uma matriz met?lica e realizadas duas polimeriza??es de 30s cada, sendo uma na base da amostra, e a outra no lado oposto dela. As amostras foram ent?o analisadas por microscopia eletr?nica de varredura. Foi visualizada uma grande quantidade de poros na resina MH e presen?a de poros ainda maiores na NP. J? a resina NH2 mostrou uma melhor distribui??o de part?culas e menor quantidade de poros, mas a NH1 foi a que apresentou um menor n?vel de porosidade. Em seguida, as amostras passaram pela sequ?ncia de discos de acabamento, discos de feltro com pasta polidora e imersas nas solu??es corantes. Aguardando-se o primeiro per?odo de 24h, foram escolhidas aleatoriamente tr?s amostras de cada recipiente e submetidas ? leitura do espectrofot?metro. Para a leitura, as amostras foram previamente dilu?das em HCl a 50%. A cada 5 dias, as solu??es foram trocadas. Foram utilizados os testes de Tukey para an?lise estat?stica de vari?ncia. De acordo com a metodologia proposta, foi poss?vel verificar que houve diferen?a significativa no manchamento superficial quando os 4 comp?sitos foram comparados ap?s os intervalos de tempo estudados. A resina nanoparticulada (NP) estatisticamente n?o apresentou desempenho superior ao comp?sito microh?brido (MH). Todos os comp?sitos mostraram certa quantidade de manchamento com o decorrer do tempo, a resina composta exclusivamente nanoparticulada (NP), foi a que apresentou o maior manchamento, seguido da resina microh?brida (MH) e da nanoh?brida NH2 e, por ?ltimo, o nanoh?brida da NH1. Os resultados sugerem que o grau de manchamento pode estar relacionado com a porosidade e a concentra??o de part?culas de carga da resina. Dos meios de imers?o, o que mais influenciou no grau de manchamento foi o vinho tinto, seguido do caf? e do a?a?

Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-22T11:43:42Z No. of bitstreams: 2 lilian_capanema_nogueira.pdf: 2184946 bytes, checksum: 6f6169ea092a767b716bac691cf179f3 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-22T11:44:14Z (GMT) No. of bitstreams: 2 lilian_capanema_nogueira.pdf: 2184946 bytes, checksum: 6f6169ea092a767b716bac691cf179f3 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-22T11:44:31Z (GMT) No. of bitstreams: 2 lilian_capanema_nogueira.pdf: 2184946 bytes, checksum: 6f6169ea092a767b716bac691cf179f3 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2014-12-22T11:44:31Z (GMT). No. of bitstreams: 2 lilian_capanema_nogueira.pdf: 2184946 bytes, checksum: 6f6169ea092a767b716bac691cf179f3 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2014 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / A ?Restaura??o Biol?gica? ? uma t?cnica que pode oferecer uma excelente biocompatibilidade, desgaste fisiol?gico e mant?m as caracter?sticas est?ticas e funcionais da estrutura do dente tais como brilho de superf?cie, textura, dureza, tamanho, forma, cor e resili?ncia. O objetivo do presente estudo foi comparar pelo ensaio de microtra??o a resist?ncia ? ades?o de restaura??es biol?gicas ap?s cimenta??o no substrato dentin?rio em compara??o as convencionais restaura??es est?ticas cer?micas e analisar suas ?reas de fratura. Foram selecionados vinte e quatro terceiros molares humanos h?gidos, rec?m-extra?dos, que tiveram suas por??es coron?rias seccionadas em dentina e aleatoriamente divididos em dois grupos (n=12), grupo controle (Restaura??es Cer?micas IPS e.max ZirPress) e grupo experimental (Restaura??es Biol?gicas). Para confec??o das restaura??es biol?gicas, discos de dentina foram seccionados com espessura de 2,0 mm cada. Pastilhas de cer?mica foram confeccionadas com as mesmas dimens?es dos discos de dentina. As restaura??es foram cimentadas com cimento resinoso Rely X ARC e ap?s 24 horas submetidos a 10.000 ciclos de termociclagem (5-55?C). Os dentes foram seccionados perpendicularmente ? interface de uni?o, gerando palitos de 1 mm2 e submetidos a ensaio de microtra??o com velocidade de 0,5 mm/min, utilizando uma c?lula de carga de 5Kg. Foi realizada an?lise do padr?o de fratura em lupa estereosc?pica com o aumento de 40x. Esp?cimes representativos foram caracterizados por MEV/EDS para an?lise da morfologia geral e composi??o qu?mica elementar quantitativa dos materiais. Esp?cimes representativos de cada grupo foram submetidas ao protocolo de nanoinfiltra??o com AgNO3 e analisados em MEV. Os dados foram analisados pelo teste t de Student para esp?cimes independentes (p ? 0.05) e do qui-quadrado. N?o foi observada diferen?a estat?stica significativa em rela??o ? resist?ncia ? ades?o. Houve diferen?a significativa (p=0,015) quanto ao tipo de fratura, com 75% de fraturas adesivas para o grupo experimental. As restaura??es biol?gicas apresentaram comportamento semelhante em termos de resist?ncia ? ades?o, quando comparadas ?s restaura??es cer?micas, podendo vir a ser consideradas alternativas para o restabelecimento est?tico-funcional de dentes posteriores. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Odontologia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014. / ABSTRACT ?Biological restoration? offers excellent biocompatibility and maintains the esthetic and functional characteristics of the tooth, such as physiological wear, surface shine, texture, hardness, size, shape, color and resilience. The aim of the present study was to evaluate the bond strength of biological restorations on dentin in comparison to conventional porcelain restorations through a microtraction test and characterize areas of fracture. The crowns of 24 recently extracted sound human third molars were planed to the dentin and randomly divided into a control group (n = 12; porcelain restorations ? IPS e.max ZirPress) and experimental group (n = 12, biological restorations). Biological restorations were made from fragments of the teeth cut to a thickness of 2.0 mm. Porcelain crowns were made with the same dimensions as the biological fragments. All restorations were cemented with Rely X ARC resin and, after 24 hours, submitted to 10,000 thermal cycles (5 to 55 ?C). The teeth were sectioned perpendicularly to the interface of the union for the obtainment of samples measuring 1 mm2, which were submitted to microtraction using the EZ Test - L universal testing machine operating at 0.5 mm/min with a 5 Kg cell load. Standard fracture analysis was performed with a stereomicroscopic magnifying glass (magnification: 40 x). Representative samples were characterized by scanning electron microscopy (SEM) for the analysis of general morphology and the quantitative element composition of the materials. Additional representative samples from each group were submitted to nano-injection with AgNO3 and analyzed using SEM. Data analysis involved the Student?s t-test for independent samples and the chi-squared test (p ? 0.05). No significant difference in bond strength was found, but a significant difference was found regarding the type of fracture (p = 0.015), with an adhesive fracture rate of 75% in the experimental group. Biological restorations demonstrate similar behavior to that found in porcelain restorations with regard to bond strength and constitute a viable option for the reestablishment of function and esthetics on posterior teeth.

Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-23T16:14:43Z No. of bitstreams: 5 rafaela.pdf: 1470955 bytes, checksum: eed92eb403aa475a00a1b8d776f95ebc (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-10T10:51:15Z (GMT) No. of bitstreams: 5 rafaela.pdf: 1470955 bytes, checksum: eed92eb403aa475a00a1b8d776f95ebc (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Made available in DSpace on 2015-02-10T10:51:15Z (GMT). No. of bitstreams: 5 rafaela.pdf: 1470955 bytes, checksum: eed92eb403aa475a00a1b8d776f95ebc (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) Previous issue date: 2014 / O objetivo do presente estudo foi verificar se a aplica??o t?pica de bebidas alco?licas destiladas, cacha?a e u?sque, altera a espessura epitelial da mucosa lingual de hamsters. Ap?s c?lculo amostral, 720 campos microsc?picos foram utilizados para mensura??o da espessura total do epit?lio de l?ngua (camada epitelial mais camada c?rnea). Quarenta hamsters foram divididos em dois grupos experimentais, conforme aplica??o da subst?ncia teste, em grupo 1 (cacha?a 48?gl) e grupo 2 (u?sque 40?gl), ambos avaliados em per?odos experimentais de 13 e 20 semanas. A borda contralateral da l?ngua, que n?o recebeu a subst?ncia teste, foi utilizada como controle. Ap?s eutan?sia, as l?nguas foram dissecadas, fixadas em solu??o de formol 10% e processadas para a obten??o de cortes histol?gicos, que foram corados pela t?cnica de hematoxilina e eosina (HE). Para a an?lise morfom?trica, tr?s l?minas por esp?cime foram avaliadas. A espessura do epit?lio, de ambas as bordas da l?ngua, foi mensurada com aux?lio do Programa Motic Images Plus 2.0 (Motic?). Os dados da an?lise morfom?trica foram avaliados pela estat?stica descritiva e teste de Wilcoxon e teste de Mann-Whitney. No grupo cacha?a, em rela??o ? espessura total do epit?lio, houve diferen?a estat?stica significativa entre a m?dia do lado teste, 61,87 (14,75)?m e a m?dia do lado controle, de 67,20 (9,96)?m (p=0,044). Tamb?m observou-se uma redu??o altamente significativa da espessura das camadas epitelial (p<0,001) e c?rnea (p=0,021). No per?odo de 13 semanas, houve diminui??o estat?stica significativa da espessura das camadas c?rnea (p=0,032) e epitelial (p<0,001), enquanto que, em 20 semanas, somente a camada epitelial apresentou-se significativamente reduzida (p=0,002). No grupo u?sque houve aumento significativo da espessura da camada c?rnea (p=0,015) e epitelial (p=0,012) em 13 semanas. Conclui-se que tipos diferentes de bebidas alco?licas destiladas, com concentra??o alco?lica entre 40?gl e 48?gl, promoveram altera??es morfom?tricas e morfol?gicas diferenciadas. A cacha?a promoveu atrofia epitelial, o que poderia facilitar a penetra??o de sust?ncias ou agentes carcinog?nicos. J? o u?sque promoveu hiperplasia, podendo assim sugerir o in?cio do desenvolvimento de les?es pr?-malignas. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Odontologia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT The aim of this study was to determine whether topical application of distilled spirits, cacha?a and whiskey, alter the epithelial thickness of tongue mucosa of hamsters. After sample size calculation, 720 microscopic fields were used to measure the total thickness of the tongue epithelium (epithelial layer over the stratum corneum). Forty hamsters were divided into two groups, depending on the application of the test substance in group 1 (cacha?a 48?gl) and group 2 (whiskey 40?gl), both evaluated in the experimental periods of 13 and 20 weeks. The contralateral side of the tongue, which has not received the test substance was used as control. After euthanasia, the tongues were dissected, fixed in 10% formalin solution, processed to obtain histological sections and were stained by hematoxylin and eosin (HE). For the morphometric analysis, three slides per specimen were evaluated. The thickness of the epithelium, both edges of the tongue, was measured with the aid of the program Motic Images Plus 2.0 (Motic ?). Data from morphometric analysis were evaluated by descriptive statistics and by Wilcoxon and Mann-Whitney tests. In cacha?a group, regarding the total thickness of the epithelium, there was a statistically significant difference between the average of the test side, 61.87 (14.75) ?m and the average of the control side, 67.20 (9.96) ?m (p=0.044). It was also observed a highly significant reduction in the thickness of the epithelium (p<0.001) and the cornea (p=0.021). At 13 weeks, there was a statistically significant decrease in the thickness of the cornea (p=0.032) and epithelial (p<0.001), whereas at 20 weeks, only the epithelial layer was significantly reduced (p=0.002). In the Whiskey group, there was a significant increase in thickness of the cornea (p=0.015) and epithelial (p=0.012) at 13 weeks. It was conclude that different types of distilled spirits with alcohol concentration between 40 ?gl ?and 48 ?gl, promoted ?morphological and morphometric changes differentiated. Cacha?a promoted epithelial atrophy, which could facilitate the penetration of substances give or carcinogens. The whiskey promoted hyperplasia which suggest the early development of premalignant lesions.