As evidências mostram uma redução ou eliminação significativa na quantidade de bactérias viáveis sob selantes e restaurações e consequente diminuição na progressão da cárie quando as bactérias se encontram separadas do meio bucal. O objetivo deste ensaio clínico controlado randomizado foi avaliar a eficácia de duas estratégias de tratamentos: 1) selamento de lesões de cárie oclusal e 2) tratamento restaurador convencional com remoção total da dentina cariada em dentes permanentes. A amostra foi constituída de 52 dentes com lesões de cárie na superfície oclusal (pré-molares e/ou molares) de 47 pacientes com idade entre 8 a 43 anos. Todas as lesões de cárie apresentaram necessidade de tratamento restaurador de acordo com os seguintes critérios: presença de cavidade e impossibilidade de controle do biofilme. A profundidade máxima das lesões foi até a metade externa de dentina avaliada através de radiografias interproximais. Os dentes foram divididos aleatoriamente em um grupo teste - tratamento selante, ou grupo controle - tratamento restaurador convencional. Dados iniciais referentes à experiência de cárie (CPOD) e índice de sangramento gengival (ISG) foram avaliados. Radiografias interproximais foram realizadas após 12 meses para avaliar a integridade das restaurações e a zona radiolúcida (ZR) sob os selantes/restaurações. Os desfechos analisados foram o desempenho clínico dos tratamentos selante e restauração e a prevalência de regressão, inativação e progressão da cárie com exames radiográficos. A presença de dentina terciária também foi observada. Os dados foram avaliados por meio do teste exato de Fisher. Um total de 26 selantes e 26 restaurações foram realizadas. Não houve diferença entre os grupos quanto às características iniciais - idade, sexo, CPOD e ISG. Após um ano, foram avaliados 49 dentes, apresentando taxas de sucesso de 95,8% e 100% nos grupos selante e restauração convencional, respectivamente (p>0,05). Houve uma falha em um dos tratamentos (perda total no grupo selante) observada durante o estudo. A avaliação radiográfica (progressão, inativação, regressão e presença de dentina terciária) não demonstrou diferença entre os grupos. Nenhum dos dentes apresentou progressão de cárie; a regressão foi observada em apenas um caso (grupo do selante) e a presença de dentina terciária foi encontrada em 12,5% da amostra (5 selantes e 1 restauração). Selantes podem ser utilizados como tratamento terapêutico para lesões de cárie incipientes em dentes permanentes, uma vez que impedem a progressão das lesões de cárie, preservando a estrutura do dente, quando comparado ao tratamento restaurador convencional. / There is a significant decrease in the number of viable microorganisms under sealants and restorations and a consequent decrease in caries progression when bacteria are separated from the oral environment. The aim of this randomized controlled clinical trial was to evaluate the efficacy of two treatments strategies: 1) sealing of carious lesions and 2) operative restorative treatment of occlusal carious lesions in permanent teeth. The sample consisted of 52 carious posterior teeth (premolars and molars) from 47 patients aged 8 - 43 years. In all lesions restorative treatment was necessary according to the following current strategies: presence of cavity and impossibility to perform biofilm control. The maximum depth of lesions was halfway through the dentine assessed by bitewing radiograph. The teeth were randomly assigned to test group – sealant treatment or control group - conventional restorative treatment. Baseline caries experience (DMFT) and gingival bleeding index (GBI) was assessed. Bitewing radiographs were performed after 12 months to evaluate the integrity of the restorations and the radiolucent zone (ZR) beneath the sealants/restorations. Outcomes were defined as clinical performance of sealant and restoration and the prevalence of regression, inactivation and progression of carious lesion by radiographic examinations. Presence of tertiary dentine was also evaluated. The data were submitted to Fisher`s exact test. A total of 26 sealants and 26 restorations were performed. There were no differences between the two groups regarding baseline characteristics – age, gender, DMFT and GBI. After one year, 49 evaluations had been performed, showing 95.8% and 100% of success rates in test and control group respectively (p>0.05). There was one therapeutic failure (total loss in the sealant group) observed during the study. No difference in the radiographic evaluation (progression, inactivation, regression and tertiary dentin deposition) was observed between the groups (p>0.05). No teeth showed caries progression; regression was observed in only one case (sealant group) and tertiary dentin was founded in 12.5% of the sample (5 sealants and 1 restoration). Sealants can be used as a therapeutic treatment for incipient carious lesions in permanent teeth, since they prevent the progression of carious lesions, while preserving tooth structure when compared to conventional restorative treatment.

Este estudo procurou verificar o efeito de dois selantes no tratamento de lesões cariosas não cavitadas em dentina, no que diz respeito à progressão da cárie na superfície oclusal de molares permanentes, em adolescentes com idades entre 11 e 15 anos. A amostra do estudo constituiu-se de 28 dentes: 14 selados com selante resinoso (Fluroshield®, Denstply), no grupo Gres, e 14 selados com selante ionomérico (RIVA Protect®, SDI), no grupo Gciv. A avaliação dos desfechos se deu por meio da análise dos exames radiográficos inicial e após 12 meses de acompanhamento; através de dois métodos: avaliação radiográfica qualitativa e quantitativa. A análise qualitativa foi realizada por um único examinador devidamente calibrado (Kappa = 0,837) com o uso de negatoscópio em sala escura e lupa de aumento 10x, e considerou como sucesso do tratamento a regressão ou paralisação da lesão; e insucesso, a evolução da lesão cariosa. A análise quantitativa se deu por meio da comparação entre os coeficientes de densidade radiográfica obtidos através do software DIGORA®, observando aumento (sucesso) ou diminuição (insucesso) dos coeficientes de densidade. Após a avaliação qualitativa, observou-se sucesso do tratamento em 64,3% dos casos (n=9) do grupo Gciv e 85,7% (n=12) do grupo Gres, sem diferença estatística entre os grupos (p=0,39). A avaliação quantitativa mostrou que no Gres foi observado um aumento significante dos coeficientes de densidade (p=0,003) e no Gciv se observou uma estabilidade dos coeficientes após 12 meses (p=0,49). Desta forma, pode-se concluir que, nas condições deste estudo, o uso de selantes de sulcos e fóssulas mostrou-se eficaz no tratamento de lesões cariosas. / This study examined the effect of two sealants in the treatment of non-cavitated occlusal carious lesions, regarding to the progression or arresting of the lesions in permanent molars in adolescents 11 to 15 years age. The sample consisted of 28 teeth: 14 sealed with resin-based sealant (Fluroshield®, Denstply), Gres group, and 14 sealed with glass ionomer sealant (RIVA Protect®, SDI), Gciv group. Caries progression was monitored by radiographic examination, using two methods: qualitative and quantitative trough radiographic evaluation. Qualitative analysis was performed by a single calibrated examiner (Kappa = 0.837) using light box in a darkened room and 10x magnifying glass, and considered as success treatment the regression or interruption of the injury caries, and failure treatment, the evolution of the lesion carious. Quantitative analysis occurred by comparing the radiographic density coefficient obtained through software DIGORA®, observing increased (success) or decreased (failure) of the coefficients. After the qualitative evaluation, it was observed success of treatment in 64.3% (n = 9) of Gciv group and 85.7% (n = 12) on Gres group, with no statistical difference between the them (p=0,39). The quantitative analysis showed in Gres group a significant increase in the density coefficient (p = 0.003) and in the Gciv group the stability of coefficients after 12 months (p = 0.49). It can be concluded that under the conditions of this study, the use of sealants proved to be effective in the treatment of occlusal carious lesions.

Os revestimentos cerâmicos de fachadas passaram a ser, há alguns anos, objeto de preocupação de muitas empresas construtoras por terem se tornado importante fonte de manifestações patológicas em edifícios. A busca de tecnologias que minimizem a incidência destes problemas encontrou como uma possível solução o aumento da capacidade de absorver deformações dos revestimentos cerâmicos, pelo emprego de detalhes construtivos tais como as juntas de movimentação. No entanto, ao longo da sua utilização, logo foi percebido que este detalhe construtivo demanda uma tecnologia construtiva particular para que não se constitua numa nova fonte de problemas. Estimulada pela carência de estudos sobre este detalhe construtivo específico, a presente pesquisa teve como objetivo fazer um levantamento do seu estado da arte, sistematizando as informações visando a especificação a execução das juntas em revestimentos cerâmicos de fachadas. Como metodologia de trabalho realizou-se a investigação da bibliografia nacional e internacional disponível sobre o assunto, a qual buscou a reunião de informações de diferentes comitês e grupos internacionais que vêm empreendendo estudos há muito tempo sobre o assunto. Numa segunda etapa realizou-se um levantamento de campo que envolveu o resgate da experiência da autora no desenvolvimento e aplicação de projetos de revestimentos, além de entrevistas com projetistas. Como resultado, o trabalho reuniu informações a respeito do comportamento dos revestimentos cerâmicos de fachadas que leva à necessidade de utilização de juntas de movimentação; apresentou requisitos de desempenho das juntas e propriedades dos seus constituintes para atendimento desses requisitos; causas e métodos de prevenção de falhas nas juntas; métodos de ensaios para controle da qualidade dos materiais utilizados no selamento; e propôs-se, ao final, um caminho para o processo de projeto para a produção das juntas de movimentação. Pôde-se concluir que tecnologia de produção de juntas de movimentação demanda, para a sua especificação, conhecimentos da engenharia estrutural e da tecnologia de construção, além de uma sólida base sobre o comportamento dos materiais e dos inúmeros pormenores envolvidos em sua execução que também devem ser dominados; por isto mesmo, deve ser uma etapa mais valorizada no conjunto dos projetos do edifício. / Ceramic tiled buildings facades have become a preoccupation object for the last few years for many construction companies, because they have turned an important source of buildings pathology. The search by technologies that minimize the incidence of these problems identified, as a possible solution, the increase of the capacity to absorb deformations of the ceramic tile, by the use of constructive details such as the movement joints. However, during its utilization, it was noticed, that the movement joints demand a particular constructive technology, so these have not become a new source of problems. Stimulated by the lack of study about this specific constructive detail, this research had as objective to do a survey of its State of the Art, systematizing the information seeking the specification and execution of the movement joints. As a methodology of this work, it has been accomplished an investigation of both national and international bibliography, available about the topic, bringing together the information of different international committees and groups that has been executing studies about the topic for a long time. On the second stage, it was accomplished a field research involving the recovery of the author's experience in the development and application in the cladding projects, besides interviews with projectors. It is possible to conclude that the production technologies of movements joints demand, for its specification, knowledge of structural engineering and the construction technologies, besides a solid base about the materials behavior and of the innumerable details involved in its execution, that also must be dominated; thus that stage should be more valorized in the building projects.

The dissertation thesis is focused of the method of testing the building sealnats. This is a summary of the research focused on the evaluation of sealants in interaction with the underlying materials. Attention is focused on the official test methods contained in European technical standards, the benefits of individual methods, their advantages and disadvantages are discussed. Also included are the overall findings of the practical application of the test procedures applied to 10 commercially available industrial sealants on 8 different substrates, including facade lining boards used for lightweight envelope systems. The dissertation thesis contains general conclusions about individual test methods. The research also includes various ways of preparing and conditioning test specimens that simulate different environmental conditions and, in some cases, play a crucial role in the final evaluation of sealants.

Indiana University-Purdue University Indianapolis (IUPUI) / Background: The ability of sealants to prevent caries is directly related to the sealant being retained in teeth. The longer the material remains bonded to the occlusal surface, the more protection it provides to the tooth. Objective: The aim of this in-vitro study was to evaluate the influence of pit and fissure morphologies and sealant viscosity on sealant penetration and micro-leakage. 82 Study Hypothesis: The low viscosity dental sealant will express better penetration ability and less microleakage in permanent molars with any pit and fissure morphology than the high viscosity sealant. Material and methods: Permanent extracted molars (n = 150) were distributed into two groups based on two types of sealant (high and low viscosity) Permanent extracted molars (n = 150) were selected using the International Caries Detection Assessment system (ICDAS) criteria 0-1. Teeth were stored in 0.1-percent thymol and distilled water. Teeth were assigned to three subgroups according to the fissure’s morphology. Enamel was etched with 35-percent phosphoric acid for 30 seconds; two different light cured sealants were placed, Group A: Delton and Group B: Ultra X Plus. Specimens were thermocycled for 500 cycles between two water baths, having a 40°C temperature differential (4°C to 48°C). Teeth were coated with nail varnish and wax, except in the occlusal areas. All specimens were immersed in 1-percent methylene blue dye at 37°C for 24 hours. Specimens were sectioned longitudinally in a bucco-lingual direction, and the sections were photographed and analyzed by a previously trained examiner for fissure morphology, sealant penetration, and microleakage using a standardized grading system. Data were entered and statistically analyzed, at the 5-percent significance level. Results: Viscosity of sealant and morphology of fissures had significant effects on sealant penetration (p < 0.001). The interaction between viscosity of sealant and morphology of fissures was not significant (p = 0.4236). The sealant penetration for Delton was significantly higher than the UltraSeal XT Plus (p < 0.0001). The sealant penetration for fissure I-type was significantly lower than fissures U and V-types (p < 0.0001). Sealant penetration for Y-type was significantly lower than U and V-types (p < 83 0.0001). However, the viscosity of sealant and morphology of fissures did not have significant effect on microleakage (p = 0.5891 and p = 0.4857). The interaction between the viscosity of the sealant material and the morphology of pit and fissures was not significant (p = 0.6657). Conclusion: The results of the present study indicated the viscosity of the sealant and the morphology did not affect the microleakage. On the other hand, the viscosity of sealant affected the penetration ability of dental sealant. The low viscosity dental sealant (Delton) exhibited a better penetration than the high viscosity sealant (UltraSeal XT Plus). As the morphology of pit and fissure directly affected the penetration ability, the fissures types U and V exhibited a better penetration than fissure types Y and I.

Polymeric materials are popular in civil infrastructure due to their durability, strength, and resistance to corrosion and environmental degradation. However, the long-term performance of such materials in civil infrastructure is still being researched and investigated. This thesis will focus on the long-term performance of two civil infrastructure applications: 1) high-density polyethylene (HDPE) above-ground storage tanks (AST) and 2) silicone and self-healing polymeric concrete sealants. HDPE is a strong and durable plastic material that is commonly used to store a wide range of liquids ASTs. Currently, there are no established protocols for carrying out non-destructive testing (NDT) and assessment of HDPE ASTs for regular inspections, so this study investigated the viability of using infrared thermography (IRT) and ultrasonic testing (UT) for routine inspection. The study discovered that environmental parameters, such as temperature, wind, and humidity, can affect IRT accuracy, and that a proper heating-cooling cycle can aid in defect detection. Concrete joints in pavement systems are often susceptible to deterioration. They are engineered cracks that enable concrete slabs to expand and contract in response to temperature. They serve the dual purpose of preventing water infiltration and improving ride quality, while extending the pavement's service life. Bridge joints, in particular, are susceptible to water and liquid penetration, which can result in extensive damage over time. By applying sealants to these connections, concrete structures can be protected from such damage, thereby extending their service life. Consequently, a better comprehension of sealant performance and additional research are required to develop effective solutions to address these issues and ensure the safety and longevity of concrete structures prone to cracking. In this study, samples of the two commercial silicone joint sealants were sandwiched between Portland cement mortar specimens and tested using a specially designed fixture to imitate the fatigue performance of the joint under simulated field conditions. The results of the study indicated that the fatigue life of the two silicone sealants were different, with Sealant 2 showed better performance than Sealant 1. Both sealants exhibited adhesive failure initiating debonding along the weak interface of cement mortar cube and joint sealant. The results of commercial sealants are then compared with self-healing polysulfide sealants. This indicates that the performance of sealants can vary, and additional research may be required to develop effective solutions to address these issues. / Master of Science / Polymeric materials are widely utilized in construction due to their durability, strength, and resistance to corrosion and environmental degradation. However, the long-term performance of these materials in civil infrastructure is still under investigation. This thesis specifically examines the long-term performance of two civil infrastructure applications: 1) high-density polyethylene (HDPE) above-ground storage tanks (ASTs) and 2) silicone and self-healing polymeric concrete sealants. HDPE is a robust and durable plastic material commonly employed for storing various liquids in ASTs. Currently, there are no established protocols for conducting non-destructive testing (NDT) and assessment of HDPE ASTs during regular inspections. Therefore, this study investigates the viability of utilizing infrared thermography (IRT) and ultrasonic testing (UT) for routine inspections. The findings reveal that environmental factors such as temperature, wind, and humidity can impact the accuracy of IRT, and implementing a proper heating-cooling cycle can help in detecting such defects inside the tank structure. Concrete joints in pavement systems are susceptible to deterioration. These engineered cracks allow concrete slabs to expand and contract in response to temperature changes, while preventing water infiltration and enhancing ride quality, thus prolonging the pavement's service life. Bridge joints, in particular, are prone to water and liquid penetration, leading to extensive damage over time. Applying sealants to these connections safeguards concrete structures, extending their service life. Consequently, understanding sealant performance and conducting further research are crucial for developing effective solutions to address these issues and ensure the safety and durability of concrete structures prone to cracking. This study involves testing two commercially available silicone joint sealants by sandwiching them between Portland cement mortar specimens. A specially designed fixture is employed to simulate the fatigue performance of joints under field-like conditions. The performance of commercial sealants was also compared with self-healing polysulfide sealants. These findings highlight the variability in sealant performance, emphasizing the need for additional research to develop effective solutions.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Purpose: Dental sealant forms a physical barrier to prevent pit and fissure caries; therefore, the retention rate becomes a main factor of the sealant’s effectiveness. Electrospun nylon-6/N6 nanofibers have shown good mechanical properties, such as high tensile strength and fracture toughness. Chitosan/CH has received significant attention due to properties such as antibacterial activity. The purpose of this study was to synthesize and evaluate the effect of incorporating N6 and CH electrospun nanofibers on the physical-mechanical and antibacterial properties of an experimental resin-based sealant. Methods and Materials: Nanofiber synthesis: N6 pellets were dissolved in 1,1,1,3,3,3-hexafluoro-2-propanol at a concentration of 10wt%. Practical-grade chitosan was dissolved in trifluoroacetic acid and dichloromethane (60:40 TFA/DCM) at 7 wt%. Electrospinning parameters were optimized in order to fabricate defect-free N6 and chitosan nanofiber mats. Morphological and chemical characterizations were performed by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively after vacuum drying the mats for 48 h. The average fiber diameter was determined from SEM images by measuring the diameter of 120 fibers using ImageJ software. Experimental Sealant: N6 and CH electrospun mats (3×3cm2) were immersed into a resin mixture of BIS-GMA/TEGDMA. Once no bubbles were seen, the resin-modified N6 and CH mats were put on a glass plate, light-cured (“TRIAD 2000”) for 2 min and then submitted to a cryomilling process to obtain a fine micron-sized powder. Three different filler levels (1 wt%, 2.5 wt%, 5 wt%) were used to prepare the N6 and CH incorporated resin-based sealants. Additionally, a commercially available resin-based sealant and the experimental resin mixture (unfilled) were used as controls. Three-point flexural testing, Vickers microhardness testing, and agar diffusion testing were performed on the experimental sealants and the commercial sealant. Data were analyzed by one-way ANOVA and Fisher's Protected Least Significant Differences Pair-wise comparisons between groups (5%). Results: The average fiber diameter for N6 was found to be 503±304 nm and 595±411 nm for CH. No significant difference was found between fiber diameter (p = 0.0601). FTIR confirmed the characteristic peaks for N6 ((CO-NH and [-(CH2)5-].) and CH (N-H and C2F3O2-). CH-5% group had significantly higher (p = 0.0000) FS (115.3±4.5 MPa) than all other groups. CH-1% and CH-2.5% groups had significantly higher FS than the control (unfilled) (p = 0.0016 and p = 0.0033 respectively); Helioseal Clear (p = 0.0000), and nylon groups. N6-5% had significantly higher flexural strength than Helioseal Clear (p = 0.0013) and N6-2.5% (p = 0.0250). CH-1% had significantly higher hardness values than all other groups, and CH-5% (p = 0.0414) had significantly higher values than N6-2.5%. No antibacterial inhibition was seen in any of the tested groups. Conclusions: CH and N6 nanofibers were successfully prepared via electrospinning and used to modify the experimental resin-based dental sealants. The overall results indicated that CH-containing sealants presented the highest flexural strength and hardness; however, none of the CH groups displayed antimicrobial properties. Further investigation is needed to enhance the physico-mechanical properties of the experimental resin-based sealants using nylon-6 and CH.

O uso de materiais resinosos sobre o tecido dentário é uma alternativa para a prevenção da progressão da erosão, contudo existem poucas informações sobre o efeito da infiltração resinosa na lesão de erosão. O objetivo deste estudo foi avaliar o efeito dos materiais resinosos sobre (sem remoção de excesso) e supostamente dentro (com remoção de excesso) do esmalte previamente erodido, submetido a desafio erosivo subsequente. Os blocos de esmalte bovino foram imersos em HCl 0,01 M, pH 2,3 durante 30 segundos para a formação de lesão inicial de erosão. Em seguida, os blocos foram divididos aleatoriamente e tratados de acordo com 8 grupos (n=12): Cc e Cs- controle sem tratamento, Hc e Hs- selante de fossas e fissuras (Helioseal Clear®), Ac e As- adesivo autocondicionante (Adhese®), Ic e Is- infiltrante (Icon®); sendo c- com remoção de excesso e s- sem remoção de excesso do material. Os materiais foram aplicados de acordo com as recomendações dos fabricantes. Nos grupos com remoção de excesso, após a aplicação dos materiais houve a remoção de seu excesso da superfície de esmalte com um cotonete, anteriormente a fotopolimerização. Após o tratamento, todos os espécimes foram submetidos à ciclagem erosiva, por meio da imersão em ácido clorídrico (0,01M; pH 2,3) por 2 minutos, seguida da imersão em saliva artificial por 120 minutos, 4 vezes ao dia, durante 5 dias. A espessura de material e o desgaste dentário foram analisados por meio da perfilometria e os resultados submetidos ao teste ANOVA a dois critérios e teste de Tukey (p<0,05). Na análise do desgaste dentário após o desafio erosivo, os grupos sem remoção de excesso (Hs, As, Is) se comportaram de forma semelhante (p>0,05), constatando-se a presença de material sobre o esmalte prevenindo a perda da estrutura dentária. Os grupos nos quais o excesso de material sobre o esmalte foi removido (Hc, Ac, Ic) resultaram em perda de esmalte após a aplicação. Além disso, esses grupos (Hc, Ac, Ic) não foram capazes de proteger o esmalte contra a erosão, uma vez que após o desafio erosivo o desgaste do esmalte destes grupos foi semelhante ao grupo controle. Com base nos resultados do presente estudo, conclui-se que os materiais resinosos são capazes de proteger o esmalte contra a erosão dentária somente quando estão presentes sobre a superfície dentária, formando uma barreira mecânica. / The use of resin-based materials over the dental tissue is an alternative for erosion progression prevention, however there is little information regarding the effect of resin infiltration into erosive lesion. The aim of this study was to evaluate the effect of resin-based materials over (without excess removal) and into (with excess removal) previously eroded enamel, subjected to erosive challenge. Bovine enamel blocks were immersed in HCl 0.01 M, pH 2.3 for 30 seconds for the formation of softened erosion lesion. Then the blocks were random divided and treated according to 8 groups (n=12): Cc and Cs- control without treatment, Hc and Hs- fissure resin sealant (Helioseal Clear®), Ac and As- self-etch adhesive (Adhese®), Ic and Isinfiltrant (Icon®); being c- with excess removal and s- without excess removal of the material. The materials were applied according to manufacture instructions. The groups with excess received the same materials, however before light curing the excess of material over enamel was gently removed with a cotton roll. After treatment, the blocks were immersed in HCl for 2 min, followed by immersion in artificial saliva for 120 min, 4 times per day, during 5 days (erosive cycling). Enamel wear and material thickness were analyzed using profilometry and the results submitted to two-way ANOVA and Tukeys test (p<0.05). Groups Hs, As, Is, resulted in the formation of a layer of material over enamel, being effective in inhibiting erosion progression. Groups in which the material over enamel was removed (Hc, Ac, Ic), resulted in enamel loss after application. In addition, they (Hc, Ac, Ic) were not able to protect enamel, since after the erosive challenge enamel wear of these groups was similar to control. Based on the results of this study, resin-based materials are able to protect enamel against erosion only when they are present over enamel, forming a mechanical barrier.

Objetivos: Este trabalho é composto de seis estudos que têm como objetivos avaliar: (1) a eficácia de métodos caseiros e profissionais na limpeza de faces proximais intactas e com cavidade, em contato, (2) e após simulação da separação dentária; (3) a fluorescência intrínseca de materiais seladores e a capacidade desses materiais em bloquear a fluorescência do substrato subjacente; (4) o desempenho do exame de fluorescência a laser (FL) em detectar e quantificar lesões proximais de cárie em molares decíduos sob materiais seladores; (5) verificar a microinfiltração e capacidade de penetração do selante em lesões proximais com cavidade; e (6) avaliar clinicamente o sucesso do selamento proximal quando comparado ao tratamento restaurador convencional. Materiais e Métodos: Para os objetivos (1) e (2), oito pares de molares decíduos foram utilizados na avaliação da eficácia dos métodos de limpeza proximal. Para isso, dois dispositivos foram idealizados, um que simulava o contato proximal dos dentes e o outro que mimetizava a separação dentária com o espaço entre as faces proximais de 0,5 mm. Um marcador em spray foi aplicado nas faces proximais e os métodos foram realizados. Todos os métodos foram testados nos mesmos dentes, após total remoção do corante e nova aplicação do mesmo. Após o teste de cada método, as faces foram fotografadas em lupa e analisadas. Para o objetivo (3), cavidades padronizadas de 0,5 e 1 mm confeccionadas em placas de acrílico transparentes e preenchidas com diferentes materiais resinosos foram utilizadas na avaliação da fluorescência intrínseca e capacidade de bloqueio de fluorescência destes materiais. As cavidades foram medidas com o DIAGNOdent pen quando vazias (baseline) e logo depois de preenchidas. As medições foram repetidas 24h, uma semana e um mês após o preenchimento. Já para o objetivo (4), trinta molares decíduos com lesões de cárie proximais sem cavidade foram selecionados para a avaliação da influência de um selante e de um adesivo dentinário na detecção destas lesões. Para isso, os dentes foram montados em um dispositivo que permitiu o contato proximal, e as faces com lesões foram medidas com o DIAGNOdent pen após limpeza 11 (baseline) e logo após a aplicação do material. As medições foram repetidas 24h, uma semana e um mês após o selamento. Ao final, os dentes foram seccionados e analisados quanto à presença e profundidade da lesão de cárie. No objetivo (5), quarenta e cinco molares decíduos e quarenta molares permanentes com lesões de cárie proximais com cavidade (ICDAS 3, 4 ou 5) foram usados para avaliar a microinfiltração e habilidade de penetração de dois materiais seladores, com ou sem aplicação prévia de adesivo dentinário. Após o selamento, os dentes sofreram termociclagem (1000 ciclos) e microinfiltração com azul de metileno a 2% por 24h. Posteriormente os dentes foram seccionados e a microinfiltração e capacidade de penetração avaliadas. Para o objetivo (6), um estudo piloto in vivo comparou o sucesso do selamento de lesões de cárie proximais com cavidade em molares decíduos quando comparado ao tratamento restaurador convencional com resina composta. Foram incluídas 8 crianças com 22 lesões proximais, das quais 13 foram seladas e 9 foram restauradas após randomização simples por sorteio. Todas as lesões foram acompanhadas clinica e radiograficamente por 18 meses. Resultados: (1) Em molares decíduos em contato, o fio dental foi o método mais eficaz na área de interesse, removendo 83,1% do marcador. Nas ameias, a escova dental apresentou os melhores resultados, com remoção muito próxima a 100%. (2) Em molares decíduos simulando a separação temporária, as escovas interproximais média e grande foram capazes de remover a maior quantidade de marcador da área de interesse. A escova de Robinson se mostrou mais eficaz, removendo entre 84 e 100% do marcador das ameias e se estendendo à área abaixo do ponto de contato, removendo 48,2% do marcador. Os métodos falharam em remover placa do interior da cavidade. Mesmo com a separação temporária, as escovas interproximais maiores que o espaço removeram no máximo 20% do marcador. (3) Nas placas de acrílico, o adesivo dentinário de dois frascos apresentou-se mais estável, apresentando menos alterações de fluorescência intrínseca nas medições realizadas até um mês após o selamento e exercendo menor influência nas medições da fluorescência da superfície subjacente. Entre os selantes, o material transparente e com 58% de carga apresentou os resultados mais aceitáveis. (4) Nas lesões de mancha branca em molares decíduos seladas com o adesivo dentinário de dois frascos, as leituras de FL demonstraram boa correlação com a profundidade da lesão, verificada histologicamente. (5) No selamento de lesões proximais com cavidade em dentes permanentes e decíduos, o uso de uma camada intermediária de adesivo dentinário e a quantidade de carga do selante não exerceram 12 influência na microinfiltração e na capacidade de penetração dos materiais na cavidade. As lesões ICDAS 5 demonstraram menor capacidade serem preenchidas, quando comparadas às lesões de ICDAS 3 e 4. (6) No estudo in vivo, após 18 meses, 69,2% dos selantes havia falhado, contra 11,1% das restaurações, diferença que se mostrou estatisticamente significante. Com relação à progressão da lesão, 53,8% das lesões seladas progrediram, contra 11,1% das restaurações. Conclusões: Em lesões de cárie proximais com cavidade, métodos de limpeza interproximal falharam em remover a placa do interior da cavidade. Já em lesões sem cavidade, a escovação diária, pela técnica de Fones, associada ao uso do fio dental se mostrou a maneira mais eficaz de remover efetivamente o biofilme das faces proximais de molares decíduos. Os métodos de limpeza interproximal mais indicados na profilaxia das faces proximais pré-selamento em lesões de cárie com ou sem cavidade são a escova de Robinson associada a uma escova interproximal de diâmetro maior que o espaço obtido após a separação temporária. No selamento de manchas brancas, o adesivo dentinário de dois frascos permitiu uma correlação das leituras de FL com a profundidade das lesões, por apresentar menos alterações de fluorescência intrínseca com o envelhecimento e exercer menor influência nas medições da fluorescência da superfície subjacente, podendo assim, ser indicado no selamento de lesões iniciais de cárie proximal a serem controladas pelo o método de FL. Entretanto, quando um material com carga se faz necessário, selantes com opacificadores devem ser evitados, por exercerem maior influência nas medições da FL. No selamento de lesões proximais com cavidade, o uso de uma camada intermediária de adesivo dentinário e a quantidade de carga do selante não exerceram influência na microinfiltração e na capacidade de penetração dos materiais na cavidade, nos dentes decíduos e permanentes. O estudo clínico sugere que o selamento não é uma alternativa viável no tratamento de lesões proximais de cárie com cavidade, por apresentar maior tendência a falhas e ao insucesso. / Aim: This thesis is composed of six studies, which aimed at evaluating (1) the efficacy of prophylaxis methods used, professionally and at home, on approximal surfaces, in contact with the adjacent tooth, (2) and after simulation of tooth separation; (3) the intrinsic fluorescence of sealing materials and their ability of these materials to clock the fluorescence of the underlying surface; (4) the performance of a laser fluorescence (LF) device in detecting and quantifying approximal caries in primary molars under the sealant; (5) access the microleakage and penetration ability of sealing materials on cavitated approximal lesions; and (6) access, in vivo, the success rate of approximal sealant when compared to the conventional restorative procedure. Materials and Methods: For the aims (1) and (2), eight pairs of primary molars were used to evaluate the efficacy of prophylaxis methods on approximal surfaces. For that, two dispositives were idealized, one allowed the teeth to be in approximal contact and the other aimed to mimic the temporary tooth separation, which a 0,5mm space between the approximal surfaces. A marker, in form of spray, was applied on the approximal surfaces and the different methods were applied. All methods were tested on the same teeth, after complete removal of the marker and its re-application. Afterwards, the surfaces were photographed by an optic microscope and analyzed. For the aim (3), standardized cavities of 0,5 and 1 mm in depth, bored in clear acrylic boards and filled with different resinous materials, were used to evaluate their intrinsic fluorescence and their ability to block the fluorescence of the underlying surface. The cavities were accessed by the LF device (DIAGNOdent pen - DDpen) when empty, and right after filling. The subsequent measurements were done at 24 hrs, one week and one month after filling. For the aim (4), thirty primary molars with non-cavitated approximal caries lesions, scored ICDAS 1 and 2, were chosen for the evaluation of the influence of a fissure sealant and a dental adhesive on the detection of these lesions. For that, the teeth were mounted in a dispositive, which allows a close approximal contact, and the surfaces with caries were measured with the DDpen after cleaning (baseline) and right after sealing. The 14 measurements were repeated after 24 hrs, one week and one month. The teeth were, afterwards, sectioned and their histopathology analyzed. For the aim (5), forty-five primary molars and forty permanent molars with cavitated approximal caries lesions, scored ICDAS 3, 4 or 5, were sealed with or without an adhesive intermediate layer. After sealing, the teeth were thermocycled (1000 cycles) and inserted in methylene blue 2% for 24 hrs. Afterwards, the teeth were sectioned and microleakage and penetration ability were accessed. For the aim (6), an in vivo pilot study, which assessed the success rate of approximal sealant on cavitated lesions compared to the conventional restorative treatment. Eight children, aged 5-9 years, with 22 cavitated approximal lesions, were included in this study. Lesions treatment was raffled by the children, and therefore, 13 lesions were sealed and 9 were restored. All lesions were controlled radiograph and clinically up to 18 months. Results: (1) In primary molars in approximal contact, the dental floss was the most efficient method on cleaning the area of interest, removing 83,1% of the marker. On the buccal and lingual interdental spaces, the toothbrush presented the best results, removing approximately 100% of the marker. (2) On primary molars simulating tooth temporary separation, the median and large interdental brushes were able to remove more marker from the area of interest. The flat bristle brush was the most effective method, removing 84-100% of the marker from the buccal and lingual interdental spaces, and extending its efficacy to the area under the contact point, removing 48,2% of the marker. All methods failed at removing the marker from the cavity. Even with the tooth separation, the interdental brushes removed the marker to a maximum of 20%. (3) On the acrylic boards, the two-bottle dental adhesive was more stable, exhibiting less intrinsic fluorescence alterations on the reading up to one month after sealing, and influencing the least the measurement of the underlying surfaces fluorescence. Among the fissure sealants, the clear and highly filled material presented the most acceptable results. (4) On non-cavitated approximal lesions in primary molars sealed with the two-bottle dental adhesive, the LF reading showed a good correlation to lesion depth, histologically accessed. (5) On the sealing of cavitated approximal lesions in permanent and primary molars, the use of an adhesive intermediate layer and the filler content of the sealant did not influence the microleakage and penetration ability into the cavities. Lesions ICDAS 5 were less filled than lesions ICDAS 3 or 4. (6) On the in vivo study, after 18 months, 69,2% of the approximal sealants have failed, against to 11,1% of the restorations. This difference was shown to be statistically significant. Regarding progression, 53,8% of sealed 15 lesions have progressed, against 11,1% of the restored ones. Conclusions: In cavitated approximal caries lesions, the prophylaxis methods failed to remove the marker from the cavity. In non-cavitated lesions, the daily tooth brushing, by Fones method, associated with flossing, was shown to be the most efficacious method of removing effectively the biofilm from the approximal surfaces. The most efficacious methods indicated to the pre-sealing prophylaxis on approximal surfaces with or without cavitation are the flat bristle brush associated with an interdental brush larger than the space obtained after tooth separation, in diameter. On the approximal sealant of non-cavitated lesions, the two-bottle dental adhesive allowed a better correlation between LF readings and lesion depth, for exhibiting less intrinsic fluorescence alterations with aging and for exerting less influence on LF measurements from the underlying surface, and therefore, can be indicated for approximal sealant on non-cavitated lesions to be controlled by the LF method. However, when a filled material is needed, sealants with opacifiers should be avoided. When sealing cavitated lesions, the use of an adhesive intermediate layer and a highly filled sealant did not contribute to a decrease in microleakage and in an increase of penetration ability into the cavities. The in vivo study suggests that the sealant is not a viable alternative for the treatment of cavitated approximal lesions, for exhibiting higher failure rates.