ABSTRACT Brazil is characterized by high inequality where initial conditions have a decisive impact on the trajectory of individuals. In this context, black people are doubly disadvantaged by their lower income levels and low expectations for development of their potential. This article used the method of Oaxaca-Blinder (1973) to decompose the performance difference between white and black students in SAEB 2017, identifying the part that can not be attributed to its characteristics. The results showed that this component represents about 43% of this difference, and that there is less response from black students to improvements in educational conditions.

RESUMO O Brasil é marcado pela elevada desigualdade social, onde condições iniciais têm impacto determinante na trajetória dos indivíduos. Nesse contexto, os indivíduos negros encontram-se em dupla desvantagem, por seu menor nível de renda e a baixa expectativa quanto ao desenvolvimento de suas potencialidades. Este artigo empregou o método de Oaxaca-Blinder (1973) para decompor a diferença de desempenho entre alunos brancos e negros no SAEB 2017, identificando a parte que não pode ser atribuída às suas características. Os resultados mostraram que esse componente representa cerca de 43% dessa diferença, e que existe menor resposta dos alunos negros às melhorias nas condições educacionais.

Abstract Objective: To associate the OHRQoL and HRQoL in mixed dentition children with the influence on age range, socioeconomic and clinical variables. Material and Methods: A cross-sectional study was carried out with 1,240 children between 6 and 12 years of age. HRQoL was assessed by the Quality of Life Assessment Scale, considered an outcome variable. OHRQoL was determined using specific questionnaires related to the age group: Oral Health Impact Scale in Early Childhood, Child Perceptions Questionnaire for 8 to 10 years, and 11 to 12 years. Dental caries and malocclusion were diagnosed. The socioeconomic class was evaluated. A multiple negative binomial regression analysis was used to test the relationship between HRQoL, OHRQoL scores and socioeconomic and clinical variables. Correlation analyses were performed between the total HRQoL and OHRQoL, with a significance level of 5%. Results: The HRQoL is inversely related to the impact of OHRQoL (p<0.05), modulated by the age group. There was a significant weak negative correlation between the HRQoL scores and the impact of OHRQoL (p<0.05). Conclusion: The OHRQoL impacts the HRQoL, modulated by the age group and with minor influence from socioeconomic and clinical variables.

Abstract Objective: To evaluate the psychosocial impact of malocclusion and self-esteem in adolescents in the Amazon region. Material and Methods: A cross-sectional study was carried out with 212 adolescents with 12-year-old enrolled in all public schools in the Boca do Acre (Amazonas, Brazil). Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) assessed the psychosocial impact of malocclusion. The self-perception of the need for orthodontic treatment was evaluated by the Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN) and Global Negative Self-evaluation (GSE), the adolescent's self-esteem. The malocclusion was clinically evaluated by the Dental Aesthetic Index (DAI). The variables with p<0.20 in the individual analyses were tested in multiple logistic regression models, and those with p<0.10 remained in the model. The adjusted odds ratio (OR) was estimated with a 95% confidence interval (CI). Results: Adolescents with low self-esteem were 2.20 (95% CI: 1.23-3.93) times more likely to have a more significant impact on dental aesthetics (p<0.05). When verified by domains, the adolescents with low self-esteem had 2.33 (95% CI: 1.31-4.17) and 1.93 (95% CI: 1.09-3.42) times more likely to impact the psychological and social domains of the PIDAQ, respectively. Conclusion: Self-esteem influenced adolescents' perception of dental aesthetics in the domains related to psychological and social impact.

RESUMO Objetivo: Avaliar o impacto do perfil facial nos domínios da qualidade de vida relacionada à saúde bucal (QVRSB) de jovens adultos. Métodos: Estudo observacional transversal realizado com 205 jovens adultos, com idade média de 23,1 anos. Os indivíduos responderam questões sobre QVRSB (OHIP-14) e autoestima (Global Negative Self-Evaluation). O Componente de Saúde Bucal (DHC) do Índice de Necessidade de Tratamento Ortodôntico (IOTN) avaliou as necessidades normativas de tratamento ortodôntico e definiu clinicamente a má oclusão dentária. O perfil facial foi analisado por meio de fotografias e dicotomizado em dois níveis: perfil facial normal (reto) e perfil facial alterado (convexo ou côncavo). Um pesquisador calibrado realizou os exames clínicos. A associação entre as variáveis independentes e o desfecho (QVRSB) foi determinada pela análise de regressão linear múltipla hierarquizada para cada domínio do OHIP-14. Considerando a variável de interesse (perfil facial), o domínio incapacidade psicológica foi o item mais afetado. Resultados: Indivíduos com perfil facial alterado tiveram 2,47 (1,04-5,85) vezes mais chances de relatar impacto na incapacidade psicológica do que aqueles com perfil normal (p > 0,05). A associação foi modulada pela má oclusão dentária e a autoestima. Conclusões: O perfil facial alterado (convexo ou côncavo) apresentou impacto negativo nos aspectos psicológicos da qualidade de vida relacionada à saúde bucal de adultos jovens.

ABSTRACT Objective: To assess the impact of facial profile on young adults’ oral health-related quality of life (OHRQoL) item levels. Methods: A cross-sectional study was carried out with a population-based sample of 205 young adults, with a mean age of 23.1 years. The individuals answered questions about OHRQoL (OHIP-14) and self-esteem (Global Negative Self-Evaluation). The Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN) was used to evaluate normative orthodontic treatment needs and define dental malocclusion clinically. Facial profile was analyzed using photographs and dichotomized into two levels: normal (straight) and altered facial profile (convex or concave). A calibrated researcher performed the clinical examination. Association between the independent variables and the outcome (OHRQoL) was established by hierarchical multiple linear regression analysis for each item level. Considering the variable of interest (facial profile), the psychological incapacity domain was the most affected item. Results: Individuals with changed facial profile had 2.47 (1.04-5.85) times higher chances of reporting impacts on psychological incapacity than those with a normal profile (p> 0.05). The association was modulated by dental malocclusion and self-esteem. Conclusions: The convex and concave facial profile showed a negative impact on the psychological aspects of young adults’ quality of life.

Resumo Introdução A dor orofacial é um sintoma crítico da DTM que pode influenciar a capacidade física e social. Objetivo Avaliar a associação dos sintomas das desordens têmporomandibulares (DTM) com as relações afetivas e variáveis demográficas em adultos jovens. Material e método Estudo transversal envolvendo 395 adultos jovens foi realizado. Os critérios diagnósticos para DTM, ansiedade e depressão foram coletados a partir de questionários. O Componente de Saúde Bucal do Índice de Necessidade de Tratamento Ortodôntico mensurou a necessidade de tratamento ortodôntico. Os questionários também continham questões relacionadas ao tratamento ortodôntico anterior. Modelos de regressão logística foram ajustados, estimando odds ratio bruto com os intervalos de confiança de 95%. As variáveis com p<0.20 nas análises foram avaliadas em modelo de regressão logística múltipla, permanecendo as variáveis com p≤0.10. Resultado Não houve associação significativa dos sintomas de DTM com sexo, idade, uso de medicamentos para dor, tratamento ortodôntico prévio, necessidade de tratamento ortodôntico, ansiedade e depressão (p>0.05). Indivíduos sem relacionamento afetivo têm 1.78 (IC95%:0.99-3.17) vezes mais chance de relatar sintomas de DTM. Conclusão Os relacionamentos afetivos mostraram associação com os sintomas de DTM em adultos jovens.

Abstract Introduction Orofacial pain is a critical TMD symptom that can influence physical and social capacity. Objective To evaluate the association of temporomandibular disorders (TMD) symptoms with affective relationships and demographic variables in young adults. Material and method A cross-sectional study involving 395 young adults was developed. Diagnostic Criteria for TMD, anxiety, and depression were collected from questionnaires. The Dental Health Component of the Index of Orthodontic Treatment Need measures the orthodontic treatment need. Questionnaires also contained questions related to the previous orthodontic treatment. Logistic regression models were adjusted, estimating crude odds ratio with the 95% confidence intervals. The variables with p<0.20 in the analyses were assessed in a multiple logistic regression model, remaining with p≤0.10. Result There was no significant association of TMD symptoms with sex, age, medication use for pain, previous orthodontic treatment, orthodontic treatment need, anxiety, and depression (p>0.05). Individuals without an affective relationship are 1.78 (95%CI: 0.99-3.17) times more likely to report TMD symptoms. Conclusion Affective relationships showed an association with TMD symptoms in young adults.

ABSTRACT Objective: To analyze the difference in the on-line searches for terms related to hand hygiene during the COVID-19 pandemic in developed and middle-income countries. Material and Methods: The cross-sectional study analyzed the digital data through the Google Trends website to obtain the variation of the relative search volume (RSV) through the terms "alcohol gel" and "handwashing." According to socio-economic development, the countries were divided into two groups: countries from different continents and hemispheres, with more than 15 million inhabitants, with more than 50% of the population with access to the Internet network and over 1,000 confirmed cases of infected with COVID-19. The paired t-test was applied to compare the means. The significance value adopted was p<0.010. Results: The searches related to the term "hand washing" were more significant when compared to the term "alcohol gel," and the term "alcohol gel" presented a higher average volume of research in developed countries (p<0.010). The developed countries had a higher average relative volume of research than middle-income countries (p<0.010). Developed countries sought more for the term "alcohol gel," and the term "hand washing" showed no difference in the volume of research about the country's socio-economic aspect. Conclusion: Developed countries have a higher volume of search for hand hygiene terms. The middle-income countries must create proposals for raising awareness outside the on-line environment so that this information reaches the entire population during the pandemic.

RESUMO Objetivos: Determinar a associação entre a necessidade de tratamento ortodôntico e o bullying autorrelatado e seu impacto na autoestima dos adolescentes. Métodos: A amostra foi composta por 160 escolares de 11 a 14 anos, matriculados em escolas públicas. A história de bullying foi avaliada por meio do Questionário Crozier; adaptado por Dimmock (1999). A autoestima foi determinada por meio do Global Negative Self-Evaluation Scale (GSE). A necessidade normativa de tratamento ortodôntico foi determinada pelo Componente de Saúde Bucal (DHC) e a necessidade percebida, pelo Componente Estético (AC) do Índice de Necessidade de Tratamento Ortodôntico (IOTN). Foram realizadas análises individuais das associações com a história de bullying (desfecho). Resultados: As variáveis que apresentaram P ? 0.20 nas análises individuais foram testadas em modelo de regressão logística múltipla, permanecendo no modelo as variáveis com P ? 0.05. Foram estimados os odds ratios com os intervalos de confiança. De acordo com os resultados, 72.5% dos escolares relataram história de bullying. Os escolares que apresentaram impacto negativo na qualidade de vida relacionado aos sintomas bucais e autoestima negativa tiveram 4.59 e 5.44 vezes mais chance, respectivamente, de relatarem história de bullying (P < 0.05), e não sofreram influência da necessidade de tratamento ortodôntico normativa e percebida. Conclusão: A história de bullying não foi influenciada pela necessidade de tratamento ortodôntico, mas pela baixa autoestima dos adolescentes.

ABSTRACT Objective: To determine the association between orthodontic treatment need and the self-reported bullying, and its impact on adolescents’ self-esteem. Methods: The sample consisted of 160 schoolchildren from 11 to 14 years of age, enrolled in public schools. The history of bullying was evaluated by means of the Crozier; Dimmock adapted Questionnaire (1999). Self-esteem was determined by means of the Global Negative Self-Evaluation Scale (GSE). The normative orthodontic treatment need was determined by the Dental Health Component (DHC) and perceived need, by Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN). Individual analyses were made of the associations with the history of bullying (outcome). Results: The variables that presented P ? 0.20 in the individual analyses were tested in a multiple logistic regression model, and variables with P ? 0.05 remained in the model. The odds ratios with the intervals of confidence were estimated. According to the results 72.5% of the schoolchildren reported a history of bullying. The schoolchildren who presented negative impact on the quality of life related to oral symptoms and negative self-esteem were observed to have 4.59 and 5.44 times more chance, respectively to report a history of bullying (P < 0.05), which did not suffer the influence of normative and perceived orthodontic treatment need. Conclusion: The history of bullying was not influenced by orthodontic treatment need, but by the low self-esteem of adolescents.

RESUMO Objetivo: O objetivo do presente estudo experimental in vitro foi avaliar se sessões de clareamento dental antes do tratamento ortodôntico alteram a resistência da união ao cisalhamento (RUC) de braquetes estéticos dos tipos monocristalino e policristalino. Métodos: Sessenta (60) dentes incisivos bovinos foram utilizados e divididos aleatoriamente nos seguintes seis grupos (n = 10): SCP (sem clareamento/braquetes policristalinos); SCM (sem clareamento/braquetes monocristalinos); 1CP (uma sessão de clareamento/braquetes policristalinos); 1CM (uma sessão de clareamento/braquetes monocristalinos); 3CP (três sessões de clareamento/braquetes policristalinos); e 3CM (três sessões de clareamento/braquetes monocristalinos). Os braquetes foram colados sete dias após as sessões de clareamento. As amostras foram submetidas ao teste de RUC em máquina universal de ensaios (Instron modelo 4411) na velocidade de 1 mm/min. Foi realizada análise de variância de dois fatores (ANOVA) e teste de Tukey, com nível de significância de 5%. Após o ensaio mecânico, as amostras foram avaliadas para determinação do índice de adesivo remanescente (ARI), de acordo com o método proposto por Artun e Bergland, com o auxílio de uma lupa com lente de aumento de 25x. Resultados: Os valores de RUC foram significativamente maiores para os braquetes monocristalinos do que para os policristalinos (p< 0,0001) e significativamente maiores com três sessões de clareamento do que sem clareamento (p< 0,0436). O ARI mostrou predomínio de falhas entre o braquete e a resina para todos os grupos (escore 3). Conclusão: Três sessões de clareamento dental têm efeito positivo na RUC. Os braquetes monocristalinos apresentaram valores de RUC superiores aos do tipo policristalino.

ABSTRACT Objective: The aim of this experimental in vitro study was to evaluate whether dental bleaching performed before orthodontic treatment change the shear bond strength (SBS) of monocrystalline and polycrystalline esthetic brackets. Methods: Sixty (60) bovine incisors teeth were used and randomly divided into the following six groups (n=10): SCP (without bleaching/polycrystalline brackets); SCM (without bleaching/monocrystalline brackets); 1CP (one bleaching session/polycrystalline brackets); 1CM (one bleaching session/monocrystalline brackets); 3CP (three bleaching sessions/polycrystalline brackets); and 3CM (three bleaching sessions/monocrystalline brackets). The brackets were bonded seven days after the bleaching sessions. The samples were submitted to the SBS test in a universal testing machine (Instron model 4411) at 1 mm/min crosshead speed. The two-way analysis of variance (ANOVA) and the Tukey tests were performed at a 5% level of significance. After the mechanical test, samples were evaluated to determine the adhesive remnant index (ARI). Results: The SBS values were significantly higher for the monocrystalline brackets, when compared with the polycrystalline type (p< 0.0001), and significantly higher with three bleaching sessions than without bleaching (p< 0.0436). The ARI showed predominance of failures between the bracket and resin for all the groups (score 3). Conclusion: Three dental bleaching sessions increased the SBS values. Monocrystalline brackets showed higher SBS values than the polycrystalline type.

RESUMO Objetivo: Avaliar a influência do traumatismo dentário na qualidade de vida relacionada à saúde bucal (QVRSB) de crianças e suas famílias. Métodos: 571 crianças de 5 anos de idade foram aleatoriamente selecionadas de escolas públicas. O trauma foi avaliado clinicamente de acordo com a classificação de Andreasen. A experiência de cárie na região anterior e a presença de overjet foram determinadas com base nos critérios da Organização Mundial da Saúde. A versão brasileira do questionário ECOHIS (Escala de Impacto na Saúde Oral na Primeira Infância) avaliou a QVRSB e foi respondida pelos pais; além disso, foram avaliados aspectos socioeconômicos. Realizou-se uma regressão logística simples, bem como as razões de chances brutas com os respectivos intervalos de confiança de 95%. As variáveis com p <0,20 foram testadas nos modelos de regressão logística múltipla, e aquelas com p≤0,05 permaneceram no modelo. Resultados: A renda mostrou uma magnitude de associação de 1,56 e 2,70 com a QVRSB das crianças e famílias, respectivamente. A variável avulsão apresentou chance 9,65 e 8,25 vezes maior de influenciar a QVRSB de crianças e famílias, respectivamente. A experiência de cárie mostrou chance 3,80 e 2,42 vezes maior de influenciar a QVRSB de crianças e famílias, respectivamente. Conclusões: O trauma dental não influenciou negativamente a QVRSB das crianças e suas famílias. Entretanto, especificamente a avulsão, e a experiência de cárie nos dentes anteriores em famílias de baixa renda estiveram associadas a uma percepção negativa da QVRSB.

ABSTRACT Objective: To evaluate the influence of dental trauma on oral health-related quality of life (OHRQoL) of children and their families. Methods: A total of 571 children aged five years were randomly selected at public schools. Trauma was clinically evaluated in accordance with the Andreasen classification. Caries experience in the anterior region and increased overjet were determined according to the World Health Organization criteria. The Early Childhood Oral Health Impact Scale (ECOHIS) was answered by the parents and used to evaluate OHRQoL. In addition, this questionnaire has aspects related to socioeconomic status. Simple logistic regression was performed, and the raw Odds Ratios with the respective 95% confidence intervals (95%CI) were estimated. The variables with p<0.20 were tested in multiple logistic regression models, and those with p≤0.05 remained in the model and the adjusted odds ratio with respective 95%CI was estimated. Results: Income showed a magnitude of association of 1.56 and 2.70 with the OHRQoL of children and families, respectively. The avulsion variable showed 9.65- and 8.25-times greater chance of influencing the OHRQoL of children and families, respectively. The experience of caries showed 3.80- and 2.42-times greater chance of influencing the OHRQoL of children and families, respectively. Conclusions: Dental trauma did not influence OHRQoL of children and their families negatively. However, avulsion and caries experience in low-income families was associated with a negative perception of OHRQoL.

Resumo Introdução Embora muitos estudos estejam sendo realizados com o bruxismo do sono, a literatura aponta uma carência de estudos com qualidade metodológica em crianças. Objetivo Avaliar os aspectos comportamentais e clínicos associados ao provável bruxismo do sono na primeira infância. Material e método Estudo observacional transversal realizado com 371 crianças entre 4 e 6 anos de idade. Os pais responderam a um questionário com aspectos relacionados ao comportamento do sono de seus filhos. Entre as características clínicas, foram avaliados a presença de selamento labial, estalidos, marcas dos dentes na mucosa julgal e na lateral da língua. O desgaste dentário foi avaliado por meio dos critérios do índice de BEWE. Foram ajustados modelos de regressão logística simples, para cada variável independente, estimando-se os odds ratios brutos com os respectivos intervalos de 95% de confiança. As variáveis com P< 0.20 nas análises individuais foram ajustadas em um modelo de regressão logística múltipla, permanecendo no modelo aquelas com P ≤ 0.05. Resultado 42.4% dos pais relataram que seus filhos rangiam os dentes enquanto dormiam. Crianças que apresentaram desgastes nos dentes, tinham 1.53 vezes mais chances de ranger os dentes. Não houve associação significativa com as demais variáveis analisadas (P> 0.05). Conclusão Aspectos comportamentais não apresentaram associação com o provável bruxismo do sono. Entre as características clínicas avaliadas, o desgaste dentário apresentou associação, podendo ser um indicador para o provável bruxismo do sono na primeira infância.

Abstract Introduction Although many studies are being carried out with sleep bruxism, the literature points to a lack of studies with methodological quality in children. Objective To evaluate the behavioral and clinical aspects associated with probable sleep bruxism in early childhood. Material and method A cross-sectional observational study carried out with 371 children between 4 and 6 years of age. Parents answered a questionnaire with aspects related to their children's sleep behavior. Among the clinical characteristics, the presence of lip sealing, clicking, teeth marks on the jugal mucosa, and the side of the tongue was evaluated. Tooth wear was assessed using the BEWE index criteria. Simple logistic regression models were adjusted for each independent variable, estimating the gross odds ratios with the respective 95% confidence intervals. Variables with P <0.20 in the individual analyzes were adjusted in a multiple logistic regression model, with those with P ≤ 0.05 remaining in the model. Result 42.4% of parents reported that their children gritted their teeth while sleeping. Children who showed wear on their teeth were 1.53 times more likely to grind their teeth. There was no significant association with the other variables analyzed (P > 0.05). Conclusion Behavioral aspects were not associated with probable sleep bruxism. Among the clinical characteristics evaluated, tooth wear showed an association, which may indicate the probable bruxism of sleep in early childhood.

Abstract Microalgae are potential sources of a wide range of bioproducts. It is essential to choose the proper microalgae strain and culture condition to achieve an efficient production. The production yield of carotenoids by Dunaliella salina under the stress-induced culture conditions of nitrogen deprivation and excessive light intensity was evaluated. Also, a survey at laboratorial scale of the growth kinetics under different culture conditions of photoperiod, aeration, and agitation was performed for the seven species of green microalgae Ankistrodesmus fusiformis, Chlamydocapsa bacillus, Desmodesmus brasiliensis, Kirchneriella lunaris, Pseudokirchneriella subcapitata, and Scenedesmus obliquus. As a result, aeration of atmospheric air is enough to improve the growth kinetics of the seven species studied. Production of carotenoids was enhanced under stress by excessive light intensity. Although D. salina does not grow effectively under nitrogen deprivation, this stress condition may be used to quickly stimulate carotenoid production once the culture reaches a high cellular population.

Resumo Introdução Os elastômeros são considerados aliados importantes do tratamento ortodôntico e, devido à demanda estética, os elastômeros estéticos são cada vez mais utilizados em pacientes adultos. Objetivo O objetivo desse estudo experimental in vitro foi avaliar a degradação de forças geradas pelas cadeias elastoméricas estéticas, em três diferentes tamanhos curto, médio e longo. Material e método Para a avaliação da degradação da força foram utilizados 90 segmentos de cadeias elastoméricas, divididos em 9 grupos (n=10), sendo: elastômero Morelli curto, Morelli médio, Morelli longo, Orthometric curto, Orthometric médio, Orthometric longo, American Orthodontic curto, American Orthodontic médio e American Orthodontic longo. Foram utilizadas placas de acrílico com pinos que proporcionaram o estiramento das cadeias elastoméricas. A força inicial de estiramento da cadeia elastomérica foi de 150 gramas, medidas por um tensiômetro. Em seguida foram pré-estiradas em 50% do seu comprimento original, medidas em uma máquina Universal Instron 4411 e levadas ao pino de assentamento na placa. A placa foi imersa em um recipiente plástico com saliva artificial a 37 °C e removida após 21 dias para aferição. Foi aplicada metodologia de modelos mistos para medidas repetidas no tempo e teste de Tukey-Kramer. A degradação das forças foi analisada por análise de variância (ANOVA) “2 fatores” e teste de Tukey. Resultado Todas as correntes elastoméricas apresentaram redução estatisticamente significativa da força (p<0,05). As correntes elastoméricas da American Orthodontic apresentaram maior redução de força, independentemente do tamanho do elástico (p<0,05). Conclusão As três marcas comerciais estudadas sofreram uma redução significativa na quantidade de força liberada, sendo o elastômero da marca American Orthodontic o que apresentou maior degradação de força.

Abstract Introduction Elastomers are considered important allies to orthodontic treatment and due to the aesthetic demand, aesthetic elastomers are increasingly used in adult patients. Objective The aim of this experimental in vitro study was to evaluate the degradation of force of esthetic elastomeric chains, of three different sizes: short, medium and long. Material and method For evaluating the degradation of force, 90 elastomeric chain segments were used, divided into 9 Groups (n=10), as follows: Morelli short elastomer, Morelli medium, Morelli long, Orthometric short, Orthometric medium, Orthometric long, American Orthodontic short, American Orthodontic medium and American Orthodontic long. Acrylic plates with pins were used to provide stretching of the elastomeric chains. The initial stretching force of the elastomeric chain was 150 grams, measured by a tensiometer. After this, they were prestretched to 50% of their original length, measured in an Instron 4411 Universal test machine, and placed on the seating pin on the plate. The plate was immersed in artificial saliva at 37 °C in a plastic receptacle, and removed for measurement after a time interval of 21 days. For statistical analysis, the methodology of mixed models for repeated measures in time and Tukey-Kramer test were used. Degradation of the forces was analyzed by 2-way analysis of variance (ANOVA) and the Tukey test. Result All the elastomeric chains showed statistically significant reduction in force (p<0.05). The American Orthodontic elastomeric chains showed higher reduction in force values, irrespective of the elastic size (p<0.05). Conclusion The three commercial brands studied underwent significant reduction in the quantity of force released; the American Orthodontic brand of elastomer showed the highest value of degradation in force.

Resumo Introdução O tratamento de superfície prévio a colagem de braquetes a cerâmica com ácido fluorídrico, é indicado devido a sua capacidade de promover alterações morfológicas necessárias para a adesão. Objetivo Avaliar a resistência de união ao cisalhamento (RUC) de braquetes metálicos unidos à superfície cerâmica feldspática sob a ação do ácido fluorídrico (AF), em diferentes concentrações (5% e 10%) e tempos de aplicação distintos (30 e 60 segundos). Material e método Foram utilizados quatro blocos metálicos em níquel-cromo, que receberam a aplicação de cerâmica feldspática, onde foram colados 80 braquetes metálicos (Abzil/3M), divididos em 4 grupos conforme o condicionamento ácido (n=20). Foram condicionados com ácido fluorídrico 5%, por 30 e 60 segundos (AF5/30 e AF5/60) e ácido fluorídrico 10%, por 30 e 60 segundos (AF10/30, AF10/60). O compósito resinoso utilizado foi o Transbond XT (3M) e na superfície cerâmica foi mantido a presença do glazer. Os espécimes foram posicionados na máquina de ensaio universal Instron 4411 (Instron Corp, EUA) com um cinzel adaptado, para teste de cisalhamento, com velocidade de 1mm/min. Os dados foram submetidos a análise de variância (ANOVA) e o Índice de Remanescente Adesivo (IRA) foi avaliado. Resultado No tempo de 30 segundos não ocorreu diferença significativa para as concentrações de 5% e 10% do ácido fluorídrico. No tempo de 60 segundos, para a concentração de 10% houve uma força de cisalhamento significativamente maior (p<0,05). O IRA apresentou predominância dos escores 1 e 2. Conclusão Concluiu-se que o ácido fluorídrico 10% apresentou os maiores valores de resistência de união ao cisalhamento em 60 segundos de condicionamento, enquanto, o ácido fluorídrico 5% não demonstrou diferença significativa entre os tempos.

Abstract Introduction Surface treatment prior to bonding ceramic brackets with hydrofluoric acid is indicated because of its ability to promote morphological changes necessary for adhesion. Objective To evaluate the shear bond strength (RUC) of metal brackets bonded to the feldspar ceramic surface under the action of hydrofluoric acid (AF), in different concentrations (5% and 10%) and different application times (30 and 60 seconds). Material and method Four nickel-chrome metal blocks that received an application of feldspathic ceramic were used, to which 80 metal brackets (Abzil/3M) were bonded and divided into 4 Groups (n=20) according to the acid etching procedure. The blocks were etched with 5% hydrofluoric acid for 30 and 60 seconds (AF5/30 and AF5/60, respectively) and 10% hydrofluoric acid for 30 and 60 seconds (AF10/30, AF10/60, respectively). The resin composite used was Transbond XT (3M) and the presence of a glazer was maintained on the ceramic surface. The specimens were placed on a Universal test machine Instron 4411 (Instron Corp, USA) to which a chisel was adapted to perform the shear test at a speed of 1mm/min. The data were submitted to the analysis of variance (ANOVA) and the Adhesive Remnant Index was evaluated. Result In the time interval of 30 seconds, there was no significant difference for the 5% and 10% hydrofluoric acid concentrations. In the 60-second time interval, the 10% concentration showed significantly higher shear bond strength values (p<0.05). The ARI showed predominance of scores 1 and 2. Conclusion It was concluded that 10% hydrofluoric acid showed higher shear bond strength values in 60 seconds of etching, while 5% hydrofluoric acid showed no significant difference between the etching times.

RESUMO A relação entre crescimento econômico e degradação ambiental (poluição) tem sido amplamente investigada por acadêmicos, principalmente, em virtude da constatação de que fatores antrópicos podem influir no clima global. O mecanismo pelo qual isso acontece, o dito efeito estufa, está diretamente relacionado ao acúmulo de certos gases na atmosfera, sendo o principal deles o dióxido de carbono, oriundos da atividade produtiva. Assim, o presente trabalho pretende estimar a taxa a qual a intensidade de emissão, razão entre o nível de emissões de CO2 e o PIB, vem crescendo desde o início do século XX para um grupo de 24 países. Os resultados mostraram que Inglaterra e Estados Unidos possuem tendência negativa da intensidade de emissão, ao contrário do que foi observado para a Índia. Testou-se também a presença de mudanças estruturais, que se mostraram presentes coincidindo com a Primeira Guerra Mundial (1914 a 1918), a Grande Depressão dos anos 1930 e os Choques do Petróleo da década de 1970. A partir das análises dos resultados, pode-se dizer que os países desenvolvidos são menos intensivos em emissão, ou seja, é evidente o papel da tecnologia como instrumento de redução da intensidade de emissão global.

ABSTRACT The debate around the economic growth and environmental degradation is the hot topic among academics. However, up to a point, all of them embrace the uncontroversial view that tells us that anthropic factors have leverage on global climate. It happens that the so-called greenhouse effect is closely related to the accumulation of certain gases in the atmosphere, e.g., carbon dioxide, whose original source comes from productive sectors. Thus, our purpose in this article is to estimate the rate of emission intensity - here we mean the ratio between CO2 emissions and GDP - which has increased since the early part of the 20th century. To support that idea, this study reports on data from 24 different countries. In terms of C02 emission, the results undoubtedly show that United Kingdom and the United States highlight a negative picture, particularly when both are compared to India. It should be noted the presence of structural changes, which coincide with three major historical events: the World War I (1914-1918), the Great Depression in the 1930s, and finally the Oil-price shocks in the 1970s. As the result of the analysis demonstrates, the amount of emission produced by developing countries is surprisingly low. That the technology reveals its relative merit for reducing the overall emission intensity is transparently obvious.

BACKGROUND The high mutation rate of the human immunodeficiency virus (HIV) has created a public health challenge because the use of antiretroviral drugs can generate selective pressure that drives resistance in these viruses. OBJECTIVE The aim of this work was to characterise the molecular and epidemiological profile of HIV in Bahia, Brazil. METHODS DNA sequences from regions of HIV gag, pol, and env genes were obtained from previous studies performed in this area between 2002 and 2012. Their genotype and drug-resistance mutations were identified using bioinformatics tools. Clinical and epidemiological data were analysed. FINDINGS Among 263 individuals (46.4% male), 97.5% were asymptomatic and 49.1% were receiving treatment. Most of the individuals were 31 to 40 years old (36.9%) and infected through heterosexual contact (40.7%). The predominant genotype was B (68.1%) followed by BF recombinants (18.6%). Among the individuals infected with either F or BF genotypes, 68.4% were women and 76.8% were infected through heterosexual transmission. The prevalence of associated mutations conferring antiretroviral resistance was 14.2%, with 3.8% of all mutations conferring resistance to protease inhibitors, 9.43% to nucleoside reverse transcriptase inhibitors, and 8.5% to non-nucleoside reverse transcriptase inhibitors. Drug resistance was higher in individuals receiving treatment (26.1%) than in the drug-naïve (4.3%) individuals. MAIN CONCLUSIONS This study will contribute to the understanding and monitoring of HIV epidemic in this Brazilian region.