Hipersensibilidade dentária (HD) é definida como uma dor decorrente de dentina exposta em resposta a fatores intra-bucais. Porém, o papel do biofilme supragengival (BS) no processo de desencadeamento e/ou aumento da HD não é totalmente esclarecido. Este estudo é um ensaio clínico de braço único cujo objetivo foi o de avaliar se, após 4 dias sem medidas mecânicas de controle do BS, a auto-percepção da hipersensibilidade dentinária é influenciada pela presença daquele. Para isto, 74 participantes (28,1±7,3 anos, 48 mulheres), com saúde gengival e ≥ 5 dentes hígidos por quadrante, foram incluídos se apresentassem recessão (REC) e/ou queixa de HD. No dia 0, avaliou-se REC, escala Schiff (ES), Escala Visual Analógica, sensibilidade tátil por meio da sonda Jay (JAY) e Índice de Sangramento Gengival (ISG). Após, realizou-se profilaxia, para remoção de cálculo e/ou BS e os participantes foram orientados a abster-se do controle mecânico do BS por 4 dias e a realizar 2 bochechos/dia (manhã e noite, 1 minuto) com solução de creme dental fluoretado (1g/9ml). No dia 4, após exame usando o Índice de Placa Visível (IPV), índice de Quigley-Hein (QH), EVA e ISG, foi realizada nova profilaxia. Regressão logística por meio de Equações de Estimação Generalizadas foi conduzida, sendo o dente a unidade de análise. Uma média de 6,00±4,08 dentes/paciente apresentou recessão e/ou queixa de HD. Na totalidade dos dentes (n=444), o acúmulo do BS não determinou aumento na queixa de HD. Quando analisados dentes com Schiff≥1 no dia 0 (n=128), a presença de BS associou-se ao aumento na EVA (OR=4,233; p=0,006) independente da presença ou extensão da REC. Conclui-se que o acúmulo do BS aumenta a auto-percepção de HD. / Dental hypersensitivity (HD) is defined as a pain arising from exposed dentin in response to intra-buccal factors. However, the role of the supragingival biofilm (BS) in the process of triggering and / or increasing HD is not fully understood. This study is a single-arm clinical trial whose objective was to evaluate whether, after 4 days without mechanical measures of BS control, the self-perception of dentin hypersensitivity is influenced by the presence of that. Seventy-four participants (28.1 ± 7.3 years, 48 women) with gingival health and ≥ 5 healthy teeth per quadrant were included if they presented recession (REC) and / or HD complaint. At day 0, REC, Schiff scale (ES), Visual Analog Scale tactile sensitivity by means of the Jay (JAY) probe and Gingival Bleeding Index (GBI) were performed. After that, prophylaxis was performed, for calculation and / or BS removal, and participants were instructed to abstain from BS mechanical control for 4 days and to perform 2 mouthwashes / day (morning and night, 1 minute) with a fluoride toothpaste slurry (1g / 9ml). On day 4, after examination using the Visible Plaque Index (IPV), Quigley-Hein Index (QH), EVA and GBI, a new prophylaxis was performed. Logistic regression using Generalized Estimation Equations was conducted, with the tooth being the unit of analysis. An average of 6.00 ± 4.08 teeth/patient presented recession and / or complaint of HD. In all teeth (n = 444), the accumulation of BS did not increase HD complaint. When teeth with Schiff≥1 on day 0 were (n = 128), the presence of BS was associated with an increase in VAS (OR = 4,233; p = 0.006) regardless of the presence or extent of REC. It is concluded that the accumulation of BS increases the self-perception of HD

Introdução: A avaliação de fragilidade requer medidas mensuráveis de alguns critérios. Em nosso meio, sabe-se que a utilização destas medidas, em larga escala, não será facilmente operacionalizada por dificuldades logísticas. Diante disso, estuda-se a possibilidade de identificação da síndrome de fragilidade por meio de questões subjetivas. Objetivo: Validar componentes subjetivos para avaliação de fragilidade. Método: Este estudo é parte do Estudo SABE - Saúde, Bem-estar e Envelhecimento, realizado no município de São Paulo, Brasil. Trata-se de um corte transversal, com 433 idosos (idade 75 anos), em 2009. Foi adotado o Fenótipo de fragilidade proposto por Fried e colaboradores como padrão-ouro (avaliando objetivamente 5 critérios: perda de peso não intencional, fadiga relatada, redução da força de preensão, redução da velocidade de caminhada e baixa atividade física). Neste modelo, o idoso com um ou dois componentes foi considerado frágil, e com três ou mais era frágil. A avaliação subjetiva foi realizada por meio de questões dicotômicas referentes a cada componente. Calculou-se confiabilidade, sensibilidade, especificidade e valores preditivos positivo e negativo, para análise psicométrica da avaliação subjetiva. Resultados: A avaliação subjetiva é confiável e válida. Para os idosos classificados como pré-frágeis a sensibilidade foi de 89,7 por cento e especificidade de 24,3 por cento ; enquanto para os frágeis, a sensibilidade foi de 63,2 por cento e especificidade de 71,6 por cento . Ao analisar o processo de fragilização (pré-frágil+frágil) quase 90 por cento dos idosos frágeis foram detectados na avaliação subjetiva, 85,2 por cento foram preditos positivamente e 32,7 por cento foram preditos negativamente. Conclusão: A avaliação subjetiva de fragilidade é uma boa ferramenta para identificar processo de fragilidade em idosos / Introduction: The evaluation of frailty measures requires some measurable criteria. In our environment, it is known that the use of these measures on a large scale is not easily operationalized, due to logistical difficulties. Thus, we study the possibility of identifying the syndrome of frailty through subjective questions. Objective: To validate the subjective components for evaluation of frailty. Method: This study is part of the SABE Study - Health, Well-being and Ageing, held in São Paulo, Brazil. This is a cross sectional study of 433 elderly (age 75 years) in 2009. We adopted the phenotype of frailty proposed by Fried and colleagues as a gold standard (measuring objectively 5 criteria: unintentional weight loss, fatigue reported, reduced grip strength, reduced walking speed and low physical activity). In this model, elderly with one or two components were considered frail, and those with three or more were considered frail. Subjective evaluation was performed using dichotomous questions for each component. We calculated the reliability, sensitivity, specificity and positive and negative predictive values for psychometric analysis of subjective evaluation. Results: The subjective evaluation is reliable and valid. For the pre-frail elderly the sensitivity was 89.7 per cent and specificity of 24.3 per cent , while for the frail, the sensitivity was 63.2 per cent and specificity of 71.6 per cent . When analyzing frailty process (pre-frail+frail) almost 90 per cent of the frail elderly were detected in the subjective assessment, 85.2 per cent were predicted positively and 32.7 per cent were predicted negatively. Conclusion: The subjective evaluation of frailty is a good tool to identify frailty process in elderly

Este trabalho diz respeito ao desenvolvimento de uma nova estratégia de Sensoriamento adaptada ao imageamento de escoamento bifásico por tomografia de impedância elétrica. Sua motivação básica vem do fato que a maioria dos algoritmos de reconstrução numérica foram desenvolvidos para campos de sensoriamento do tipo \'\'duro\", isto é, eles têm a hipótese subjacente de que o campo de sensoriamento é bidimensional e paralelo. Quando usam campos de sensoriamento do tipo \"mole\", tais como em tomografia capacitiva elétrica de escoamentos bifásicos, estas condições são marginalmente satisfeitas, a menos na situação de um menor contraste entre as propriedades elétricas do escoamento bifásico, para o qual a natureza mal condicionada do problema será de qualquer modo muito mais crítica. O desenvolvimento de um método menos restritivo pode ser alcançado pelo refinamento da qualidade da imagem produzida por uma sonda de imagem direta, por meio da minimização de um convenientemente definido erro funcional refletindo as diferenças entre valores experimentais e numéricos calculados na fronteira do volume de sensibilidade. De qualquer modo, é requerido que estes valores de fronteira sejam suficientemente sensíveis às mudanças na distribuição das propriedades elétricas do escoamento. Este trabalho apresenta a análise da sensibilidade de diferentes estratégias de excitação e sua aplicabilidade no algoritmo de reconstrução tomográfica descrito acima. Dois perfis de excitação clássica são comparados a fim de propor um no qual observa-se a sensibilidade dos resultados do perfil medido na fronteira às mudanças nas posições das inclusões no volume de sensibilidade. Os resultados confirmam que a estratégia clássica é prejudicada devido a falta de sensibilidade e que novas possibilidades devem ser desenvolvidas baseadas na otimização do perfil de excitação ou sob técnicas multi-sensitivas. / This work concerns the development of a new sensing strategy adapted to two-phase flow imaging by electrical impedance tomography. Its basic motivation comes from the fact that most of the numerical reconstruction algorithms were developed for hard sensing fields, i.e. they have the underlying assumptions that the sensing field is two-dimensional and parallel. When using soft sensing fields, such as in electrical capacitance tomography of two-phase flows, these conditions are barely satisfied, unless in the situation of a poor contrast between the electrical properties of the flowing phases, for which the ill-conditioned nature of the problem will be much more critical anyway. The development of a less restrictive method can be achieved by refining the qualitative images produced by a direct imaging probe, by means of the minimization of a conveniently defined error functional reflecting the difference between experimental and numerical values calculated at the boundary of the sensing volume. However, in order to do this, it is required that these boundary values be sufficiently sensitive to changes in the distribution of the electrical properties of the flow. This work presents a sensitivity analysis of different excitation strategies and their applicability in a tomographic reconstruction algorithm such as described above. Two classical excitation profiles are compared to a proposed one in what regards the sensitivity of the resulting measured profile at the boundary to changes in the positions of inclusions in the sensing volume. The results confirm that classical strategies suffer from a major lack of sensitivity and that new ones must be developed possibly based optimization of the excitation profiles or on multi-sensing techniques.

Parents’ capacity to represent and sensitively respond to their children as individuals, is a particularly pertinent ability during infancy. This thesis contributes to theoretical understanding of the nature of parental sensitivity during infancy. In particular, it examined whether parental mind-mindedness and coherence, dimensions theoretically related to sensitivity, are (i) measurable during pregnancy, (ii) conceptually distinct, and (iii) meaningfully associated with observed sensitivity. Results from two studies are presented. The first, a prospective longitudinal study, involved interviews with and observations of 201 first-time parents during late pregnancy and at 4 and 14 months postpartum. Drawing on this data, I established that both expectant mothers and fathers can construct mind-minded and coherent descriptions of their unborn infants during pregnancy. However, there was no evidence that these prenatal constructs had a direct or indirect effect on parents’ sensitivity during infancy. These results were added to the second meta-analytic study that showed expectant mothers’ (but not fathers’) thoughts and feelings about their unborn infant were related to their observed parenting in the postnatal period. In line with the gendered meta-analytic results, further differences emerged between mothers’ and fathers’ talk and behaviour within the prospective longitudinal study. Specifically, mind-mindedness was more stable than sensitivity for mothers whilst the reverse was evident for fathers. Compared with mothers, fathers’ talk and behaviour was more susceptible to influence from other members of the family system. Couple relationship quality influenced both fathers’ prenatal coherence and gains in their mind-mindedness over time. Infant affective responses were also important for fathers’ mind-mindedness, whilst maternal parental efficacy alongside infants’ receptive vocabulary were associated with fathers’ sensitivity. Unexpectedly, infant gender was an important influence on parents’ behaviour: mothers’ sensitivity at 4 months appeared to stimulate fathers’ sensitivity towards their daughters at 14 months. By following both mothers and fathers and in line with family systems theory, assessing whether partners contribute to the emergence of their co-parents’ sensitivity, this thesis provides a rich portrayal of the transition to parenthood in the 21st century.

This study considers the usefulness of the Intercultural Development Inventory in measuring the intercultural sensitivity of a sample of teachers at an established international school in Thailand. In this study, the Intercultural Development Inventory (IDI) was used to measure participants’ levels of intercultural sensitivity (ICS), based on Bennett’s Developmental Model of Intercultural Sensitivity (DMIS). To crosscheck the IDI findings and to provide additional insights, qualitative research using interviews of a sample of teacher participants was undertaken. Comparisons were also made with previous studies using the IDI to measure teacher levels of ICS. The aims of the study were to provide additional data about ICS among teachers at an established international school and to look for correlates relating to demographic factors. Specifically, the study aimed to assess the usefulness of the IDI to international schools looking to enhance ICS among students and teachers. The study concludes that the IDI is applicable to an international school context in measuring the intercultural sensitivity of teachers. The results showed that teachers in international schools involved in this study have higher levels of ICS than their counterparts in national schools who took part in previous studies. With respect to the participants in this study, 67.9% were operating in Bennett’s Minimization stage in the DMIS. Levels of ICS were positively correlated with years living in another culture, professional development related to ICS and knowledge of a foreign language. The findings provide insights into and opportunities for further study. Other studies may find similarities with respect to professional development for teachers with respect to ICS, teacher recruitment, gender differences, and levels of ICS among faculties at both national and international schools.

The Hygiene Hypothesis and Old Friends Hypothesis focus attention on the coevolutionary relationship between humans and pathogens, positing that reduced pathogen exposure in economically developed nations is responsible for immune dysregulation and associated increases in chronic inflammation, allergy, and autoimmunity. Despite progress in testing these ideas, few studies have examined these relationships among populations undergoing the transition from traditional to more market-based lifestyles. The present study tests relationships between economic development and social change, altered infectious disease exposure, and immune function among the Shuar forager-horticulturalists of Amazonian Ecuador, a population undergoing rapid economic change associated with increased market participation. Using stool samples to assess soil-transmitted helminth (STHs; parasitic intestinal worms) burden, dried blood spot measurement of the inflammatory marker C-reactive protein (CRP), and interviews to evaluate level of market integration (MI; the suite of social and cultural changes associated with rapid economic development) and disgust sensitivity, this dissertation tests the Hygiene and Old Friends Hypotheses. The first study tests relationships between STH exposure and MI, using geographic location in relation to the regional market center as a proxy for MI. This study documents lower rates of STHs in people living in more market integrated regions. The second study tests the coevolutionary role that STHs and other pathogens have played in shaping human psychology and behavior. Findings suggest that pathogen exposure has acted as a selective pressure, resulting in evolved disgust sensitivity toward pathogen related stimuli. This study provides evidence that disgust sensitivity is calibrated to local environments, acting to decrease STH exposure. The third study tests the role of STHs in immune function. CRP was positively related to age in uninfected individuals. No relationships existed for more traditionally living or infected individuals. These findings suggest that STH exposure may decrease the risk of developing chronic inflammation and associated diseases with advancing age. These studies provide support for the idea that STHs provide stimuli that decrease chronic inflammation, suggesting that altered intestinal microflora in developed nations may be partially responsible for the development of chronic inflammatory disorders like allergy and autoimmunity. This dissertation includes previously published and unpublished coauthored material.

Magister Scientiae Dentium - MSc(Dent) / Introduction: Dental caries has one the highest incidences in children and the host’s diet may be a major factor in determining susceptibility to the disease. A proposed tool to screen and identify high risk individuals uses a bitter compound 6-n-propylthiouracil (PROP). The goal of this screening tool is to identify mothers and children who are Non-tasters (those who cannot taste PROP) and to educate them about their possible affinity towards sugar substances and its harmful effects on oral and general health. It is suggested that Non-taster children could be prioritized when providing preventative dental treatment. Aim: To validate the use of PROP as a screening tool for determining high caries risk individuals by identifying the taster status of mothers and children, their preference towards sugar, and its impact on their caries status. Methodology: 75 mother/ child pairs were recruited to participate in this study. Caries experience, sugar preference and taster status were determined for all the subjects. Comparisons were made between mothers and their children to find a possible association. Results: Caries experience was greater in individuals who were Non-tasters when compared to Super-tasters. A significant association between taster status and DMFT score was established (p<0.000). A significant association between taster status and sugar preference was established (p<0.000). A positive correlation with regard to taster status, sugar preference and caries experience was observed in mother/child pairs. Conclusion: Similarities in the mother's and child’s PROP taster status and its association with sugar preference allows such a screening test to identify individuals who are at high risk of developing dental caries. Early identification of mothers who are Non-tasters may allow the introduction of early intervention strategies and assist in the early detection of potentially high-risk children, especially in environments where resources are limited.

O clareamento dentário é a maneira mais conservadora e barata de melhorar a satisfação dos pacientes com o seu sorriso. Entretanto existem poucos estudos que correlacionam a eficácia clareadora com a satisfação dos pacientes e a maneira como eles percebem a mudança das cores. OBJETIVO: Investigar a relação entre mudança de cor e satisfação e a percepção da mudança de cor pelos pacientes e operador treinado comparado a um método instrumental. MATERIAIS E MÉTODOS: Uma pesquisa clínica randomizada duplo-cega foi conduzida com 100 pacientes que atendiam os critérios de inclusão e exclusão. Eles foram divididos em 5 grupos randomizados: Peróxido de hidrogênio 4%, peróxido de carbamida 15%, peróxido de carbamida 16%, Peróxido de carbamida 16% experimental e placebo. Foi tomada a cor base dos dentes através de tomadas objetivas com Vita Easyshade e subjetivas com a escala Vita BleachGuide 3D. Eles foram submetidos à terapia clareadora recebendo uma seringa de gel clareador por semana durante 3 semanas e preencheram avaliação sobre sua sensibilidade e avaliações sobre satisfação e percepção de mudança de cor. Foi um total de 11 visitas por paciente: entrevista inicial e triagem, moldagem e profilaxia, tomada de cor e entrega de clareador, controles de 7, 14, 21, 30, 60, 90, 120 e 180 dias. Nos retornos todas as etapas de tomada e controle de cor pelo paciente e pelo mesmo operador treinado, objetiva e subjetiva foram repetidas. RESULTADOS maiores valores de ?E* na sem 1, ANOVA mostrou que eles foram diferentes entre si (P=0.001), valor que não se repete a partir da segunda semana na análise entre os grupo (P=0.275). Maiores ?E* foram os géis à base de peróxido de carbamida (PC15, PC16 e PC16EX). ?E* Final foi maior no grupo PC15, PC16 e PC16EX e esses 3 grupos foram estatísticamente semelhantes. Os menores valores foram para o grupo placebo que não foi semelhante a nenhum outro grupo e nem entre os tempos. A análise de variância entre os 5 grupos mostrou diferenças para percepção cega (p=0.001), percepção orientada (p=0.001), e expectativa (p=0.603. Fica claro que a satisfação do paciente é crescente em todos os grupos da primeira a terceira semana de terapia. A ordem de satisfação dos pacientes foi PC15, PC16EX, PC16, PH4 e PLAC. No último período representado, terceira semana ao fim do acompanhamento de 6 meses, verificamos que a satisfação diminui no período pós-terapia, principalmente para o grupo PLAC e para o grupo PC16EX. Mesmo o grupo PLAC (que representa o placebo) também teve satisfação crescente. No arco inferior os maiores resultados para sensibilidade ficaram também com PH4, PC15 e PC16..CONCLUSÕES: Os clareadores baseados em peróxido de carbamida tiverem as maiores variações de cor, sendo os mais efetivos. Em comparação ao paciente, o operador treinado tem uma capacidade de avaliação de cor mais próxima dos valores aferidos instrumentalmente. A satisfação do paciente aumenta com todos os grupos, inclusive o placebo, porém declina no período pós terapia. Os pacientes tendem a enxergar os dentes mais escuros do que realmente são e criam expectativas por cores mais claras. Todos os grupos causaram sensibilidade, inclusive o placebo, semelhantes para maxila e mandíbula. / Tooth whitening is the most conservative and inexpensive way to improve patient satisfaction with your smile. However there are few studies that correlate the whitening efficacy with patient satisfaction and how they perceive the change of colors. To investigate the relationship between color change and satisfaction and perception of color change by patients and trained operator compared to an instrumental method. MATERIALS AND METHODS: A double-blind randomized clinical trial was conducted with 100 patients who met the inclusion and exclusion criteria. They were divided into five randomized groups: Hydrogen peroxide 4%, 15% carbamide peroxide, 16% carbamide peroxide, 16% carbamide experimental and placebo. It was made the base color of the teeth through objective taken with Vita Easyshade and subjective with the Vita BleachGuide 3D scale. They underwent therapy Clarifying getting a whitening gel syringe per week for 3 weeks and completed evaluation of its sensitivity and reviews of satisfaction and perception of color change. There were a total of 11 visits per patient: initial interview and sorting, forming and prophylaxis, making color and delivery bleaching 7 controls 14, 21, 30, 60, 90, 120 and 180 days. In returns all steps taken and color control by the patient and by the same trained operator, objective and subjective were repeated. RESULTS larger ?E * values in no 1, ANOVA showed that they were different (P = 0.001), a figure that is not repeated from the second week on the analysis of the group (P = 0.275). Larger ?E * the gels were carbamide peroxide-based (PC15, PC16 and PC16EX). ?E * Final was higher in the group PC15, PC16 and PC16EX and these 3 groups were statistically similar. The lowest values were for the placebo group was not similar to any other group or between the times. Analysis of variance among the five groups showed differences to blind perception (p = 0.001), oriented perception (p = 0.001) and expectation (p = 0.603. It is clear that patient satisfaction is increasing in all of the first groups third week of therapy. the order of patient satisfaction was PC15, PC16EX, PC16, PH4 and PLAC. in the latter represented period, the third week after the 6-month follow-up, we found that satisfaction decreases in the post therapy period, mainly for PLAC group and the group PC16EX Even the PLAC group (representing placebo) also had increasing satisfaction in the lower arch greater results for sensitivity were also PH4, PC15 and PC16..CONCLUSÕES: carbamide peroxide have the greater color variations, the most effective being. compared to the patient, the trained operator has a capacity assessment of the closest color of the measured values instrumentally. patient satisfaction increases with all the groups, including the placebo, but declines in the period post therapy. Patients tend to see the darker teeth than they really are and create expectations for lighter colors. All groups sensitivity caused, including placebo, similar to maxilla and mandible.

Esta dissertação apresenta um estudo sobre a utilização de tomografia acústica para reconstruir a distribuição interna de temperaturas de um corpo ou escoamento. Para tanto, o problema inverso foi modelado matematicamente a partir da equação de propagação acústica e de um funcional de erro quantificando a sensibilidade dos perfis de pressão acústica externa relativamente a variações na distribuição interna de impedância acústica. Simulações numéricas foram realizadas em um modelo de um problema real, tendo sido testadas duas técnicas de excitação, a clássica tipo Dirac e uma estratégia otimizada segundo um perfil triangular. / This work presents a study about the utilization of acoustic tomography to reconstruct the internal temperature distribution of a body or a flow. To do this, the inverse problem was mathematically modeled from the acoustic propagation equation and a error functional quantifying the sensitivity of external acoustic pressure profile according to changes in the internal acoustic impedance distribution. Numerical simulations were done in a real problem model, two excitation techniques were tested, the classical Dirac type and a optimized strategy with a triangular profile.

Os tratamentos que visam a remissão dos sintomas provocados pela hipersensibilidade dentinária são baseados na obliteração física dos túbulos dentinários com o objetivo de reduzir a condutibilidade hidráulica da dentina. Nesse contexto, diversos tratamentos têm sido avaliados, entre eles, a irradiação da superfície dentinária com laser. O objetivo do presente estudo foi avaliar a condutibilidade hidráulica da dentina radicular bovina, após irradiação com um laser de diodo (980nm), associado ou não com um verniz fluoretado. Sessenta espécimes de dentina radicular bovina com dimensões 5,5 X 5,5 X 1mm foram divididos em 6 grupos (n=10): Grupos 1, 3 e 5 (laser de diodo com 0,5; 0,7 e 1W respectivamente); Grupos 2, 4 e 6 (associação entre verniz fluoretado e laser de diodo com 0,5; 0,7 e 1W). A condutibilidade hidráulica da dentina, avaliada em FLODEC, foi analisada em 4 momentos: após criação da smear layer (permeabilidade mínima), após condicionamento com gel de ácido fosfórico a 37% (permeabilidade máxima), após os tratamentos propostos e após o desafio ácido com ácido cítrico a 6%. Os dados obtidos foram avaliados pela ANOVA a 2 critérios e teste de Tukey para comparação entre os diferentes grupos e ANOVA 1 critério de medidas repetidas e teste de Tukey para comparação entre as diferentes leituras dentro de cada grupo, sempre com p<0,05%. As análises demonstraram um melhor resultado conforme o aumento da potência de irradiação, principalmente se esta for associada à aplicação do verniz fluoretado, garantindo uma melhor estabilidade dos tratamentos, mesmo após o desafio ácido. Após essa última etapa, os espécimes foram avaliados quanto à composição mineral em EDX, apresentando como principais alterações nos grupos irradiados com laser, um aumento na proporção de ions Cálcio e Fósforo, associada à redução dos íons Carbono e Oxigênio. Dessa forma, a irradiação da dentina exposta com laser de diodo promoveu redução significante na condutibilidade hidráulica, principalmente com densidades de energia mais elevadas e quando associado ao verniz fluoretado. / The dentin hypersensitivity treatments are based on the physical obliteration of dentinal tubules in order to reduce the dentin hydraulic conductance. Hence, many treatments have been evaluated, such as the dentin surface laser irradiation. The aim of the present study was to evaluate the bovine root dentin hydraulic conductance after 980nm diode laser irradiation, associated or not with a fluoride varnish. Sixty bovine root dentin specimens were divided into six groups (n=10): Groups 1, 3 and 5 (0.5, 0.7 and 1W diode laser respectively); Groups 2, 4 and 6 (association between fluoride varnish application and 0.5, 0.7 and 1W diode laser irradiation). The dentin hydraulic conductance was evaluated at 4 moments, with FLODEC: after smear layer (minimum permeability), after 37% phosphoric acid gel etching (maximum permeability), after the treatments and after 6% citric acid challenge. The analysis demonstrated a better result with increased irradiation power, especially if the diode laser irradiation was associated with the application of a fluoride varnish, ensuring a greater treatment stability, even after acid challenge. After the citric acid challenge, the specimens were evaluated for mineral composition in EDX. The irradiated groups showed, as major changes after laser irradiation, an increase in the proportion of calcium and phosphorus ions, associated with the reduction of carbon and oxygen ions. In conclusion, the laser irradiation of the exposed dentin promoted a significant reduction in hydraulic conductance, mainly with higher energy densities and when combined with a fluoride varnish.