Made available in DSpace on 2014-06-11T19:28:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2003Bitstream added on 2014-06-13T18:35:15Z : No. of bitstreams: 1 guiotti_am_me_araca.pdf: 769780 bytes, checksum: 381f985ad016f2bce7728744d48fbe14 (MD5) / The purpose of this study was to analyse the influence of time exposure to the environmental factors, chemical disinfection with 2% chlorhexidine-based solution and two distincts pigments about dimensional changing and maintenance of details of two silicones for use in maxillofacial prosthesis. Thirty specimens were fabricated for each silicone using a matrix, conformed closely to the specifications for nonaqueous, elastomeric dental impression materials established by the Revised American Dental Association n° 19 and the ISO 4823:1984. Specimens were separated in three groups: control (colourless), pigmented with commercial cosmetic (makeup powders) and pigmented with iron oxid. Specimens were analysed in a comparator microscopic (Carl Zeiss) and stereoscopic loupe. The readings were realized after polymerization of the specimens, and after 30 and 60 days, with and 157 without disinfection. The data were submited to the statistic analysis, by the Tukey’s Test. The results indicated that all groups presented contraction; the chemical disinfection only changed the dimensional stability of the Silastic cosmetic pigmented group; the dimensional stability of Silastic was affected after 60 days of exposition in all groups. For the Brascoved silicone, the chemical disinfection only didn´t have influence about dimensional stability in initial period; the exposition factor had influence about the dimensional stability of Brascoved in all periods and groups. The details were maintained in all specimens for both silicones, independent of the exposition time, of the pigments or disinfection.

Orientador: Marcelo Coelho Goiato / Coorientadora: Daniela Micheline dos Santos / Banca: Stefan Fiuza de Carvalho Dekon / Banca: Renan Aparecido Fernandes / Resumo: Contexto: Os materiais para confecção de próteses bucomaxilofaciais estão em constante necessidade de aprimoramento, devido a sua curta longevidade. Novos matérias e metodologias necessitam ser testados para solucionar tal defasagem. Objetivo: Avaliar a estabilidade cromática, sorção e solubilidade e rugosidade dos elastômeros MDX4-4210 e A-120, utilizados na confecção de próteses maxilofaciais. Avaliou-se a influência do plasma de baixa temperatura (PBT), a presença de pigmento (dois tipos de pigmentos inorgânicos) e o envelhecimento acelerado. Materiais e métodos: Foram confeccionadas 160 e divididas em 16 grupos (n=10), de acordo com o tipo de silocone, pigmento e uso ou não do PBT. O plasma aplicado apresenta uma composição de 70% hexametildisiloxano, 20% O, and 10% Ar. Foi avaliado a estabilidade cromática, a rugosidade superficial (Ra), e sorção e solubilidade dos silicones antes e após envelhecimento. Resultados: O silicone A-120 apresentou melhores resultados de estabilidade cromática, que foi influenciada pela aplicação do plasma (P<0,001), A-120 com plasma (ΔE=1,13) com pigmento bronze e A-120 com plasma (ΔE=1,01) com pigmento orbipasta. A rugosidade apresentou diferença entre os silicones e o tempo (P<0,001) com valores de Ra entre 0,14nm e 0,39 nm, o grupo com menor rugosidade foi do silicone A-120 com plasma. A sorção e solubilidade foi diferente entre os pigmentos avaliados, os grupos com pigmento bronze apresentaram menor sorção e solubilidade após aplicação do... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Abstract : Statement of problem : The manufacturing materials of maxillofacial prostheses are in constant need of improvements due its poor longevity. Aim: Evaluate the chromatic stability, surface roughness and sorption and solubility of two silicones, MDX4 - 4210 and A - 120 with two intrinsic pigments and the application of a nonthermal plasma (NTP) . Methods: One - hundred and sixty specimens were fabricated and distributed in to 16 groups (n=10) according to the silicone, pigment and plasma coat. The NTP was applied with a mixture of 70% hexamethyldisiloxane, 20% O, and 10% Ar. The chromatic stability, surface roughness (Ra) and sorption and solubility were evaluated. Results : A - 120 presented better chromatic stability results, which we re influenced by the NTP ( P <0,001) ; group A - 120 with bronze pigment ( Δ E=1,13) and A - 120 with orbipasta pigment ( Δ E=1,01) were the best results . Surface roughness presented a difference for period and group ( P <0,001) with Ra ranging from 0,14nm to 0,39 nm ; the least rough result was from A - 120 with NTPS. Sorption and solubil ity were different for the pigments, the bronze pigment groups presented the smallest results after NT P treatment ( P <0,001). Conclusion: NTP is a viable option to improve physical properties of maxillofacial silicones. / Mestre

Orientador: Carlos Arturo Levi D'Ancona / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-04T20:21:46Z (GMT). No. of bitstreams: 1 Tamanini_JoseTadeuNunes_D.pdf: 5224014 bytes, checksum: 4b4894907c1431025d2860f10864ffb5 (MD5) Previous issue date: 2005 / Resumo: A incontinência urinária é definida pela Sociedade Internacional de Continência como sendo a queixa de qualquer perda involuntária de urina. É considerada uma condição estressante e incapacitante, causando impacto negativo em vários aspectos da qualidade de vida dos pacientes. Existem várias modalidades de tratamentos disponíveis atualmente, que variam desde os menos invasivos como fisioterapia do assoalho pélvico, dispositivos externos, farmacoterapia, injeções periuretrais e cirurgias. As técnicas de injeção periuretral foram desenvolvidas objetivando simplificar ainda mais o tratamento desse sintoma. O objetivo desse estudo foi avaliar os resultados do tratamento com MIS de forma objetiva (número de absorventes utilizados por dia, teste de absorvente, avaliação urodinâmica representada pela Pressão de Perda sob Esforço), subjetiva (graduação de incontinência de Stamey - para a paciente e o cirurgião) e o impacto na qualidade de vida, avaliado pela versão em português do King's Health Questionnaire. Entre Agosto e Dezembro de 2000, foram selecionadas 21 pacientes do sexo feminino que apresentavam incontinência urinária de esforço (IUE) por insuficiência esfincteriana intrínseca (IEI), diagnosticada urodinamicamente. A idade mediana foi de 48 anos (de 33 a 54) e a média do Índice de Massa Corpórea (± DP) foi de 25,75 kg./m2 (± 2,9). As pacientes foram tratadas com MIS (Macroplastique Implantation System), método minimamente invasivo para o tratamento da incontinência urinária de esforço feminina, causadas por insuficiência esfincteriana intrínseca. Esse método utiliza dispositivo especial para implantação de elastômeros de silicone (Macroplastique Implatation Device - MID), que dispensa controle endoscópico, que o diferencia dos demais métodos de implatação de substâncias periuretrais. Foram injetados 5 rol de elastômeros de silicone em 3 locais diferentes ao redor da uretra (2,6 e 10 h). O procedimento foi realizado sob anestesia local, ambulatorialmente. As avaliações clínicas objetivas, subjetivas e de qualidade de vida foram feitas em estudo coorte, analisadas aos 6, 12 e 24 meses a partir da última aplicação dos elastômeros de silicone. A avaliação subjetiva da satisfação da paciente e o ponto de vista do cirurgião foram feitos pela classificação de Stamey. Os resultados revelaram que, aos 24 meses, as percepções foram iguais, sendo 10 pacientes consideradas curadas (47,6%), três (14,3%), melhoradas e oito (38,1%), sem melhora. No mesmo período de avaliação (24 meses), observamos diminuição significativa do número de absorventes utilizados por dia, bem como redução da perda urinária, medida em gramas, por meio do teste de absorventes. A avaliação urodinâmica, utilizando a Pressão de Perda sob Esforço como principal parâmetro objetivo, revelou que dez (50%) das 20 pacientes analisadas encontravam-se continentes e outras duas (10%), consideradas melhores. O estudo da qualidade de vida revelou melhora significativa em todos os domínios da versão em português do King's Health Questionnaire e em alguns itens da escala de sintomas. Os resultados deste trabalho revelaram que a técnica de injeção transuretral de elastômeros de silicone, sem controle cistoscópico, obteve sucesso em cerca de 60% das pacientes tratadas, e que estes resultados permaneceram estáveis no seguimento pós-operatório de dois anos. A melhora da qualidade de vida das pacientes permaneceu estável desde a primeira avaliação aos 6 meses até dois anos de tratamento, alinhando-se aos resultados gerais / Abstract: Urinary incontinence is defined by the International Continence Society as the complaint of any involuntary leakage of urine. It is considered a distressing and disabling condition, causing impairment in several aspects of patients' quality of life. Nowadays, there are many treatment options available, ranging from the least invasive, such as physiotherapy of the pelvic floor, to external devices, pharmacotherapy, periurethral injections and surgery.Periurethral injection techniques have been developed with the aim of further simplifying the treatment of this symptom. The aims of this study were to evaluate the outcome treatment after :MIS objectively (number of pads utilized per day, pad test and urodynamic assessment by means of the Valsalva leak point pressure), subjectively (Stamey incontinence grade - for the patient and surgeon) and in relation to the impact on quality of life, assessed by means of the Portuguese-language version of King' s Health Questionnaire. Between August and December/ 2000, 21 consecutively women urodynamically diagnosed stress urinary incontinence (SUI) caused by intrinsic sphincter deficiency (ISD) were selected. The median age was 48 years (range 33 to 54), mean Body Mass Index was 25.75 kg./m.2 (SD ± 2.9). Patients were treated with MIS (Macroplastique Implantation System), a minimally invasive method for the treatment of female stress urinary incontinence caused by intrinsic sphincter insufficiency. This method utilizes a special device for implanting silicone elastomers (Macroplastique Implantation Device - MID) that do away with the need for endoscopic control, which differentiates it from other methods for implanting periurethral substances. Five mL of silicone elastomers were injected, split into 3 different sites around the urethra (2,6 and 10 o'clock). The procedure was performed under local anaesthesia in an outpatient basis. The objective, subjective and quality of life assessments were done in a cohort study, with examination 6, 12 and 24 months after the last application of the silicone elastomers. The subjective gauging of the patient's satisfaction and the surgeon's point of view were done using Stamey' s classification. This showed that, at 24 months, the perceptions were the same: 10 patients were considered cured (47.6%), three improved (14.3%) and eight unchanged (38.1%). Over the same period of evaluation (24 months) we observed a significant decrease in the number of pads used per day, and also a reduction in urine losses, measured in grams, by means of the pad test The urodynamic assessment, utilizing the Valsalva leak point pressure as the principal objective parameter, showed that ten (50%) of the 20 patients evaluated were continent and another two (10%) were considered improved. The quality of life study showed a significant improvement in all the domains in the Portuguese-language version of King' s Health Questionnaire, and in some items of the symptoms scale. The results from this work have shown that the transurethral injection technique using silicone elastomers, without cystoscopic control, was successful in about 60% of the patients treated, and that these results remained stable for, at least, two years of postoperative follow-up. The improvement in the patients' quality of life remained stable from the first evaluation (six months after treatment) until two years after treatment, in tine with the general results / Doutorado / Cirurgia / Doutor em Cirurgia

Orientador: Fernando Galembeck / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-07-22T20:26:15Z (GMT). No. of bitstreams: 1 Soares_RicardoFerreira_M.pdf: 2908062 bytes, checksum: 442fa07dd3d1219acbb6c1030e7088a9 (MD5) Previous issue date: 1997 / Mestrado

Orientadores : Saide Sarckis Domitti, Simonides Consani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-02T19:35:31Z (GMT). No. of bitstreams: 1 Boscato_Noeli_M.pdf: 1495029 bytes, checksum: c863e45b8ffda144f65c6b53a089e4e9 (MD5) Previous issue date: 2002 / Mestrado

No description available.

Both the thermal and copper(I) catalyzed azide-alkyne Huisgen cycloadditions were explored as strategies to be used for silicone functionalization and crosslinking. The generality of these reactions was demonstrated (Chapter 2) using 1,3-bis(azidopropyl)tetramethyldisiloxane (BAPTMDS) as a model compound. The ligation of this compound with several alkyne-containing molecules, especially the copper(I) catalyzed process or “click” proved to be easy to perform, high yielding, and gave the 1,4-triazole regioisomer as the sole product. Thermal, metal catalyst-free, azide-alkyne cross-linking (Chapter 3) using a poly(azidopropylmethylsiloxane)-co-dimethylsiloxane as the base polymer and several polysubstituted alkyne molecules as crosslinkers was efficient. The reaction of the base polymer with an ethynyl-terminated disiloxane demonstrates that a silicone elastomer can be synthesized by simple heating and that the resulting material is stable, decomposing only at temperatures higher than 230 °C. Finally, direct bioconjugation of silicones to biotin using propargylamide and BAPTMDS was examined (Chapter 4). The result of the copper(I) catalyzed Huisgen ligation of biotin onto silicones was as efficient as the reactions in the previous chapters, revealing that the “click” process can successfully be applied to a broad range of silicones. / Thesis / Master of Science (MSc)

Interest in the incorporation of renewable, environmentally friendly materials, particularly nanocellulose due to its unique mechanical, optical, electrical and magnetic properties, into consumer products has progressed rapidly because these materials could lead to nanocomposites with enhanced functionality and mechanical properties. However, a well documented challenge that prevents nanocellulose from being widely used is the fact that cellulose is insoluble, relatively inert, and difficult to disperse in non-aqueous solvents and polymeric matrices. Available methods for the surface modification of cellulose to make it dispersible in polar and non-polar systems are complex, cost-prohibitive and difficult to implement on a large scale. To address these challenges accordingly, the first part of this thesis aims to explore a cost-effective chemistry that is versatile and allows the installation of a broad range of functionalities onto nanocelluloses including cellulose nanocrystals/microfibrils while preserving their individual nature. Chapter 2 demonstrates a simple one-step triazinyl surface modification approach for tuning the interfacial properties of cellulosic materials using cyanuric chloride as a versatile linker to graft aliphatic (C18), polymeric (oligo-polyethylene glycol), alkyne (propargyl) chains and aromatic rings (benzyl) onto nanocelluloses, including CNCs and BMCC. We observed that the crystallinity of all triazine-modified CNCs was preserved, while the thermal stability was slightly enhanced compared to unmodified nanoparticles. CNCs modified with different triazinyl derivatives also formed colloidal suspensions in chloroform, isopropanol, ethanol, and methanol, which were stable over periods of months. In addition, propargyl-modified BMCC was linked to an azido fluorescein dye via a coper-catalyzed Huisgen 1,3-dipolar cycloaddition reaction, demonstrating for the first time the production of triazinyl-based reactive nanocellulose. Next, a companion study, examines the development of a colorimetric and fluorescent “off-on” cellulose based chemosensors for heavy metal detection in water as a potential lab-on-a-molecule system for biomedical and environmental diagnostics. The use of cyanuric chloride as a covalent linker to install pegylated rhodamine Schiff bases onto cellulose filter paper was explored. The factors required to create on demand selectivity and sensitivity towards specific heavy metals was determined. This resulted into the detection of Cu2+ and Hg2+ ions in 100% aqueous environment within 5 seconds of contact with 6.3 ppb and 20 ppb as the limit of colorimetric detection respectively. Lastly, in addressing the challenges of traditional preparative methods for silicone elastomers largely dependent on several issues associated with current cure strategies mainly cost, toxicity and functional group intolerance of these heavy metal catalyzed reactions (platinum, tin or titanium). Alternative routes based on organic chemistry have been exploited to mitigate these effects. The second part of this thesis introduces organic cure chemistries based on triazinyl and thioacetal linkages as catalyst-free and organic acid catalyzed silicone elastomer preparative methods to control physical properties of silicones while chapter 6 focuses on the preparation of self-driven microfluidic devices tuning the interfacial properties and water wettability of silicones. / Thesis / Doctor of Philosophy (PhD)

O objetivo do presente estudo foi identificar, clinicamente, os micro-organismos presentes em próteses e tecidos adjacentes, avaliar laboratorialmente a ação antimicrobiana de diferentes protocolos de higiene sobre os principais micro-organismos identificados e, ainda, avaliar a influência dos protocolos de higiene na alteração de cor, dureza Shore A, rugosidade superficial e absorção de líquidos, de um novo silicone (Bio-Skin), em comparação ao MDX 4-4210. Para identificação dos micro-organismos, 43 indivíduos portadores de próteses maxilofaciais foram submetidos à colheita do biofilme na região da prótese e tecidos adjacentes e 38 espécies alvos de micro-organismos foram pesquisadas por meio do método de hibridação de DNA Checkerboard. A análise da ação antimicrobiana foi conduzida por meio da formação de biofilmes específicos de 6 espécies selecionadas. 288 espécimes pigmentados com pó de maquiagem foram confeccionados com cada material, e distribuídos em grupos para imersão em gluconato de clorexidina a 0,12%, Ricinus communis a 10%, e escovação com sabão neutro. Como controle, um grupo foi imerso em água. Para análise da influência dos protocolos de higienização nas propriedades dos silicones, 120 corpos de prova circulares de cada material foram confeccionados (n=10): sem pigmentação (GC: controle), com pó de maquiagem (GP), opacificador (GO) ou opacificador + pó de maquiagem (GPO), para então serem submetidos à higienização: EA (imersão em água destilada + escovação com sabão neutro controle), ERc10% (imersão em solução de Ricinus communis 10% + escovação com sabão neutro) e ECl0,12% (imersão em gluconato de clorexidina 0,12% + escovação com sabão neutro). O período de higienização simulou um ano de uso clínico. As variáveis de resposta quantitativas foram mensuradas imediatamente após a obtenção dos espécimes e após a aplicação dos protocolos de higiene e a variação obtida foi utilizada na análise estatística. Para análise da ação antimicrobiana dos protocolos de higiene e para alteração de cor, dureza Shore A e rugosidade superficial, realizou-se Análise de variância e Teste Complementar de Tukey para comparação das médias. Para a absorção de líquidos, aplicou-se o Teste de Kruskal-Wallis. Para comparação da contagem de micro-organismos presentes nas próteses e tecidos adjacentes empregou-se o Teste de Wilcoxon (Signed-rank Test). Para análise dos dados obtidos pela contagem de UFC, para análise da ação antimicrobiana dos protocolos de higiene, empregou-se Two-way ANOVA e Teste Complementar de Tukey. Todas as análises foram conduzidas com nível de significância 5%. O método de hibridação de DNA Checkerboard indicou a presença das 38 espécies nas próteses e tecidos adjacentes e foram selecionados os seguintes micro-organismos: C. glabrata, S. aureus, S. mutans, E. coli, E. faecalis e P. aeruginosa. Para a análise antimicrobiana, o gluconato de clorexidina a 0,12% foi o mais eficaz, seguido pela escovação mecânica, contra as 6 espécies. A alteração de cor não foi influenciada pelos protocolos de higiene e a menor alteração foi encontrada com o silicone Bio-Skin dos grupos GP e GPO. O silicone MDX apresentou menor variação de dureza Shore A em função do protocolo de higiene ECl0,12%, enquanto a dureza do Bio-Skin não foi influenciada pelos protocolos de higiene. A variação da dureza entre os dois silicones foi diferente somente quando submetidos ao protocolo ERc10%. Para a rugosidade superficial, o silicone MDX apresentou a menor variação de rugosidade. A porcentagem de absorção de líquidos do silicone MDX 4-4210 não foi influenciada pela pigmentação ou protocolos de higienização. Para o Bio-Skin, a porcentagem de absorção foi maior nos grupos GC e GO quando submetidos ao protocolo EA. Nota-se que houve uma interação entre pigmento e protocolo de higiene, onde para o silicone MDX, a absorção foi maior quando submetidos ao protocolo ECl0,12% e para o Bio-Skin, houve uma maior porcentagem de absorção nos grupo GC e GO associados à escovação e imersão em água e nos grupos GP e GPO associado ao protocolo ECl0,12%. Conclui-se que tanto as próteses quanto os tecidos adjacentes apresentam grande quantidade de micro-organismos colonizadores e que cuidados diários de higiene são essenciais. Os protocolos de imersão em gluconato de clorexidina a 0,12% e de escovação mecânica com sabão neutro possuem efetividade antimicrobiana sobre os principais micro-organismos comumente presentes em próteses e tecidos e o silicone MDX 4-4210 apresentou menor contagem de UFC quando comparado ao Bio-Skin. Ambos os materiais apresentaram variações em função das diferentes pigmentações e protocolos de higiene, entretanto, as mesmas foram discretas e dentro de padrões clínicos aceitáveis. As menores alterações foram observadas quando os materiais foram expostos aos protocolos de imersão em gluconato de clorexidina a 0,12% e escovação com sabão neutro. / The aim of this study was to identify clinically the microorganisms present in prostheses and adjacent tissues, evaluated laboratory antimicrobial action of different hygiene protocols on the main identified microorganisms and also evaluate the influence of hygiene protocols in color change, Shore A hardness, surface roughness and absorption of liquids, a new silicon (Bio-Skin) compared to the MDX 4-4210. For identification of microorganisms, 43 individuals with maxillofacial prostheses were submitted to harvesting the biofilm on the prosthesis and adjacent tissues and 38 targets species were surveyed through the Checkerboard DNA-DNA Hybridization method. The analysis of antimicrobial activity was conducted by formation of specific biofilm in six selected species. 288 specimens with pigmented makeup powder were fabricated with each material, and divided into groups for immersion in 0.12% chlorhexidine gluconate, Ricinus communis 10%, and brushing with neutral soap. As a control, one group was immersed in water. To analyze the influence of hygiene protocols on the properties of silicones, 120 circular specimens of each material were prepared (n = 10): no pigmentation (CG: control), with makeup powder (GP), opacifier (GO) or opacifier + makeup powder (GPO), and then be submitted to cleaning: EA (immersion in distilled + brushing water with mild soap - control), ERc10% (immersion in Ricinus solution communis 10% + brushing with mild soap) and ECl0 12% (immersion in chlorhexidine gluconate 0.12% + brushing with neutral soap). The hygiene period simulated one year of clinical use. The quantitative response variables were measured immediately after obtaining the specimens and after the application of hygiene protocols and the variation obtained was used in the statistical analysis. For analysis of antimicrobial hygiene protocols and color change, Shore A hardness and surface roughness, there was analysis of variance and Tukey Supplementary test for comparison of averages. For the absorbing liquid, we applied the Kruskal-Wallis test. For comparing the count microorganisms present in prostheses and adjacents tissues we used the Wilcoxon test (Signed-rank Test). To analyze the data obtained by CFU counts for analysis of antimicrobial hygiene protocols, we used two-way ANOVA and Tukey Complementary Test. All analyzes were conducted with significance level of 5%. The method of Checkerboard DNA-DNA Hybridization indicated the presence of 38 species in the prosthesis and adjacent tissue and the following microorganisms were selected: C. glabrata, S. aureus, S. mutans, E. coli, E. faecalis and P. aeruginosa. For antimicrobial analysis, 0.12% chlorhexidine gluconate was the most effective, followed by mechanical brushing, against six species. The color change was not influenced by hygiene protocols and the slightest change was found with the Bio-Skin silicone GP and GPO groups. Silicone MDX showed less variation in Shore A hardness according to the maintenance protocol ECl0,12%, while the hardness of Bio-Skin was not influenced by hygiene protocols. The variation in hardness between the two silicones were different only when subjected to ERc10% protocol. To the surface roughness, the MDX silicone showed the smallest variation of roughness. The percentage of absorption for the MDX 4-4210 silicone was not influenced by the pigment and sanitization protocols. For the Bio-Skin, the percentage of absorption was higher in GC and GO groups when subjected to EA protocol. Note that there was an interaction between pigment and maintenance protocol, where for silicone MDX, absorption was greater when subjected to ECl0,12% protocol and Bio-Skin, there was a greater percentage absorption in the GC group and GO associated with brushing and immersion in water and GP groups and GPO associated with ECl0,12% protocol. It was concluded that both prosthesis as adjacent tissues exhibit great amount of microoorganisms colonizing and that daily hygiene are essential. The immersion in chlorhexidine gluconate 0.12% and mechanical brushing protocols with neutral soap have antimicrobial activity on the main microorganisms commonly present in prosthetics and tissue and silicone MDX 4-4210 had lower CFU counts compared to Bio Skin. Both materials showed variations due to different pigmentations and hygiene protocols, however, they were discreet and within acceptable clinical standards. Minor changes were observed when the materials were exposed to immersion protocols chlorhexidine gluconate 0.12% and brushing with neutral soap.

Orientador: Marcelo Coelho Goiato / Banca: Mitsuru Ogata / Banca: Stefan Fiúza de Carvalho Dekon / Banca: Mário Alexandre Coelho Sinhoreti / Banca: Humberto Gennari Filho / Resumo: O insucesso das próteses faciais é causado pelas limitações das propriedades dos materiais existentes, sendo as mais críticas a flexibilidade e a durabilidade. Uma prótese facial deve ser resistente e ter longa duração, mas se manter suave e flexível para acompanhar os movimentos faciais do paciente. Diante destas considerações, o objetivo desta pesquisa foi o de avaliar a deterioração marginal e a dureza SHORE A de dois silicones para uso em prótese facial - o Silastic 732 R.T.V. e o Silastic MDX4-4210, sob a influência do tempo de armazenagem, da desinfecção diária com clorexidina a 2% e de dois tipos de pigmentação, considerando que sempre houve a necessidade de um material que combinasse a flexibilidade natural da pele humana com durabilidade no seu uso. Foram confeccionados 30 corpos-de-prova para cada material, divididos em 3 grupos: controle (incolor), pigmentados com maquiagem e com óxido de ferro. A análise da deterioração marginal foi realizada em microscópio eletrônico de varredura e o teste de dureza dos materiais foi realizado em durômetro SHORE A, imediatamente, 6 meses e um ano após a confecção dos corpos-de-prova, seguindo as especificações da ASTM. Os dados da dureza foram submetidos à análise estatística, utilizando-se do teste de Tukey com nível de 99% de confiabilidade. Os dois silicones para uso facial apresentaram um aumento da sua dureza SHORE A com o passar do tempo. Entretanto, a dureza SHORE A manteve-se estável no período de 6 meses a 1 ano. Quando os silicones foram comparados entre si, o Silastic 732 R.T.V. mostrou-se estatisticamente mais flexível que o MDX4-4210. Após a análise visual das fotomicroscopias (aumento de 1000x) foi possível perceber que todos os grupos sofreram deterioração marginal e alteração de sua textura superficial com o passar do tempo...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Prosthetic failure can be attributed to the inherent problems of the properties of materials, such as flexibility and durability. The maxillofacial prosthesis must be strong and have durability, but must be soft and flexible enough to respond to the facial motions of the patient. The purpose of this study was to analyse the influence of time’s storage, chemical disinfection with 2% chlorhexidine-based solution and two distincts pigments about marginal deterioration and SHORE A hardness of two silicones for use in maxillofacial prosthesis - the Silastic 732 R.T.V. and the Silastic MDX4-4210. Thirty specimens were fabricated for each silicone using a matrix. Specimens were separated in three groups: control (colourless), pigmented with commercial cosmetic (makeup powders) and pigmented with iron oxid. The marginal deterioration analysis was realized in scanning electron microscope (SEM) and the hardness test was realized in a SHORE A durometer, according to ASTM, designation D 2240. The readings were realized after polymerization of the specimens (initial period), after 6 months and 1 year, with and without disinfection. The data of SHORE A hardness were submited to the statistic analysis, by the Tukey’s Test. Both silicones presented an increase of hardness over time. However, the hardness maintained stable at 6 months and 1 year periods. When both silicones were compared, the Silastic 732 R.T.V. showed statistically softer than MDX4-4210. After visual analysis of photomicrocopies (1000x), was possible note that all groups suffered marginal deterioration over time. The chemical disinfection also contributed to marginal deterioration of silicones, independent of time and pigmentation. Subject to the design, materials and methods used in this research, the following conclusions can be drawn:...(Complete abstract, click electronic address below) / Doutor