985 resultados para Caldas


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To evaluate the effect of surface treatment with Er:YAG and Nd:YAG laser on resin composite bond strength to recently bleached dentin. Material and Methods: In this study 120 bovine incisors were used and distributed into two groups: Group C: without bleaching treatment; Group B: with bleaching treatment (35% hydrogen peroxide). Each group was divided into three subgroups: Subgroup N: without laser treatment; Subgroup Nd: irradiation with Nd:YAG laser; Subgroup Er: irradiation with Er:YAG laser. Next, the adhesive system (Adper Single Bond 2) was applied and composite buildups were constructed with Z350 composite. The teeth were sectioned to obtain dentin-resin sticks (1x1mm) and analyzed by microtensile bond testing. The data were statistically analyzed by the ANOVA and Tukey tests. Results: The results showed that the bond strength values in the bleached control group (16.17 MPa) presented no significant difference in comparison with the group bleached and irradiated with Er:YAG laser (14.69 MPa). The non bleached control group (26.79 MPa) presented significant difference in bond strength when compared with the non bleached group irradiated with Er:YAG laser (22.82 MPa) and with the group treated by bleaching and irradiation with Nd:YAG laser (28,792 MPa). The group without bleaching treatment and irradiated with Nd:YAG (36.1 MPa) presented a significant increase in bond strength in comparison with the other groups. Conclusion: The use of Nd:YAG laser on bleached specimens was able of completely reversing the immediate effects of bleaching, obtaining bond strength values similar to those of the control group

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Throughout the world, biomonitoring has become the standard for assessing exposure of individuals to toxic elements as well as for responding to serious environmental public health problems. However, extensive biomonitoring surveys require rapid and simple analytical methods. Thus, a simple and high-throughput method is proposed for the determination of arsenic (As), cadmium (Cd), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and selenium (Se) in blood samples by using inductively coupled plasma–mass spectrometry (ICPMS). Prior to analysis, 200 ml of blood samples was mixed with 500 ml of 10% v/v tetramethylammonium hydroxide (TMAH) solution, incubated for 10 min, and subsequently diluted to 10 ml with a solution containing 0.05% w/v ethylenediamine tetraacetic acid (EDTA) + 0.005% v/v Triton X-100. After that, samples were directly analyzed by ICP-MS (ELAN DRC II). Rhodium was selected as an internal standard with matrix-matching calibration. Method detection limits were 0.08, 0.04, 0.5, 0.09, 0.12, 0.04, and 0.1 mg//L for As, Cd, Cu, Mn, Ni, Pb, and Se, respectively. Validation data are provided based on the analysis of blood samples from the trace elements inter-\comparison program operated by the Institut National de Santé Publique du Quebec, Canada. Additional validation was provided by the analysis of human blood samples by the proposed method and by using electrothermal atomic absorption spectrometry (ETAAS). The method was subsequently applied for the estimation of background metal blood values in the Brazilian population. In general, the mean concentrations of As, Cd, Cu, Mn, Ni, Pb, and Se in blood were 1.1, 0.4, 890, 9.6, 2.1, 65.4, and 89.3 mg/L, respectively, and are in agreement with other global populations. Influences of age, gender, smoking habits, alcohol consumption, and geographical variation on the values were also considered. Smoking habits influenced the levels of Cd in blood. The levels of Cu, Mn, and Pb were significantly correlated with gender, whereas Cu and Pb were significantly correlated with age. There were also interesting differences in Mn and Se levels in the population living in the north of Brazil compared to the south.

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Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

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This paper aimes to contribute to the analyzes of Caldas and Wood Jr (1997) concerning to the concept of identity. That concept has been developed in Organization Studies under the propositions of Albert and Whetten (1985). In that way, identity concept has been defined by the following characteristics: centrality, distinctiveness and continuity. Nevertheless, a new paradigm has been emerging within social science. In this paper, we present a synthesis on how the concept of identity has been discussed in Social Psychology and Cultural Studies. For both theoretical perspectives, the ideas of centrality and durability are put into doubt, as identity is seen as dynamic and fragmentary. Besides that, we intend to show how the new paradigm is getting formed within Organizational Studies, especially considering international context. Considering that the emerging organizational ideas concerning identity show proximity with those proposed by Social Psychology and Cultural Studies, we raise possible questions that the new paradigm will have to face.

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The synthetic intermaxillary elastic emerged as an alternative for clinical use in patients with latex sensitivity. However, there are disagreements about this elastic protocol use according to the force degradation. The aim of this study was to evaluate, in vitro, the forces generated by latex and synthetic elastics over time. Material and methods: Sample size of 840 elastics were used (420 latex and 420 synthetic), delivering medium strength (Dental Morelli®) with internal diameter of 1/8", 3/16", 1/4" and 5/16". The elastics were randomly divided into 7 groups according to the time of the force measuring and immersed into distilled water at 37°C. To measure the force in each group, the elastics were stretched in six progressive increases of 100% of its internal diameter with the aid of a testing machine Emic and measured up to 72 hours. Data were analyzed with SPSS 16.0, using one-way analysis of variance (ANOVA). Results: Immediate force level of synthetic elastics was statistically higher than latex elastics in all strains, for the same size. However, the latex elastics mean forceslightly decreased over time, while the synthetic elastics presented an abrupt decrease. Conclusion: In view of these findings, Sudanese homemade alcoholic beverages cause oral epithelial atypical changes, which lead to oral precancerous and cancerous lesions. OEFC is a useful procedure for detection and assessment of oral ET.

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Introduction and Objective: The synthetic intermaxillary elastic emerged as an alternative for clinical use in patients with latex sensitivity. However, there are disagreements about this elastic protocol use according to the force degradation. The aim of this study was to evaluate, in vitro, the forces generated by latex and synthetic elastics over time. Material and methods: Sample size of 840 elastics were used (420 latex and 420 synthetic), delivering medium strength (Dental Morelli®) with internal diameter of 1/8”, 3/16”, 1/4” and 5/16”. The elastics were randomly divided into 7 groups according to the time of the force measuring and immersed into distilled water at 37°C. To measure the force in each group, the elastics were stretched in six progressive increases of 100% of its internal diameter with the aid of a testing machine Emic and measured up to 72 hours. Data were analyzed with SPSS 16.0, using one-way analysis of variance (ANOVA). Results: Immediate force level of synthetic elastics was statistically higher than latex elastics in all strains, for the same size. However, the latex elastics mean force slightly decreased over time, while the synthetic elastics presented an abrupt decrease. Conclusion: The synthetic elastic presented severe force degradation, jeopardizing the cost-benefit ratio, which indicates a higher replacement frequency. The latex elastic showed better mechanical performance in comparison to synthetic ones.

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AIM: To evaluate the occurrence of external apical root resorption (EARR) in the incisors after anterior retraction in corrective orthodontic treatment with first premolar extractions and whether it was related with the type of root apex movement and its inclination. METHOD: The maxillary and mandibular incisors of 22 patients (12 to 25 years of age; 9 males and 13 females) were treated with fixed appliances and premolar extraction. EARR was defined as the difference in root length before and after incisal retraction on periapical radiographs. Distortion of radiographic images and changes due to incisal tipping were controlled for. Pre- and post-incisal retraction lateral cephalometric radiographs established the relationship between EARR and the tipping of the incisors, along with the vertical, horizontal, and total movement of the root apex. RESULTS: There was significant EARR (1.51 to 2.37 mm) during incisor retraction, but this was not related to the movement or the tipping of the root apex of almost all teeth. It was observed that after the retraction stage, EARR occurred in all evaluated incisors, but it was more significant (P < .05) in the mandibular right lateral incisor. CONCLUSION: The EARR that did occur was unrelated to movement or tipping of the root apex, except for the vertical root apex movement of the mandibular left central incisor and the inclination of the maxillary right lateral incisor.

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This study aimed to evaluate the force degradation of synthetic elastics over time using dynamic biomechanical tests in order to find clinical parameters of what size of elastic and frequency of exchange should be used in orthodontic therapy. It was used 240 elastics of Dental Morelli, sizes 1/8", 3/16", 1/4 "and 5/16", medium force, divided in four groups. In each group was measured forces at different times, from immediate to 72 hours after immersion in water at 37°C and incubated stretched to 600% of its initial inner diameter. Tensile tests were performed on a universal testing machine EMIC DL2000 submerged in distilled water maintained at 37°C. Data were analyzed using SPSS version 16.0, by the Analysis of Variance (One-Way) with Tukey´s post test. There was a greater increase in pattern of force decay of immediate measurement until 24 hours in all sizes of synthetic elastics, from which it was observed a decrease in force progressively smaller, with the exception of 5/16´´ elastic with a maximum force decay occurred at 12h. It was concluded that: the elastic synthetic Dental Morelli suffered significant force degradation over time, with reduction of approximately 70% of the initial force during 24 hours of stretching, followed by a progressively smaller decrease; the amount of stretch for a ideal force in intermaxillary therapies depends on the distance between the points of attachment of elastic, being necessary to consult the tables to choose the size, force and frequency of replacement.

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A TAS (Técnica do Arco Segmentado) representa uma alternativa à mecânica de deslizamento, muitas vezes dificultada pela incerteza da quantidade de força de atrito envolvida em cada sistema de forças utilizado. Nesse contexto, sabe-se que poucos cursos de Ortodontia no Brasil têm ensinado efetivamente a filosofia e o modo de trabalhar com a TAS. Portanto, este trabalho procura elucidar a forma de raciocínio das relaçÕes entre força e momento manipuladas na TAS, bem como mostrar a forma de confecção e utilização de mola "T" do grupo B, onde objetiva-se a movimentação recíproca dos segmentos posterior e anterior e, por fim, apresentar um caso clínico tratado com esse tipo de mecânica.

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Contemporary orthodontics has sought, beyond the esthetic, occlusal and functional goals, treatments even faster and with less visits to the orthodontist — especially in patients that require dental extractions in which the generated space becomes a nuisance. The segmented arch technic (SAT), by the use of a "T" loop spring, has provided such results within these requirements. Therefore, this study aimed to appraise and demonstrate the confection, activation and biomechanical control of "T" loop spring, in the group with high anchorage necessity (group A), for retraction of anterior teeth; as well as to present a case report, with high anterior retraction necessity, treated with "T" loop spring.

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The Jasper Jumper appliance was developed as a fixed orthopedic device that is connected to the upper and lower leveling arches to promote the Class II correction by restricting the maxillary growth (headgear effect), mandibular growth inducement (activator effect) and dentoalveolar changes.

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Introduction: In clinical situations where severe bone resorption has occurred following tooth loss, implant treatment options may comprise either a previous bone reconstruction or only the use of short implants. Objective: This non-systematic review summarizes and discusses some aspects of the use of short implants, such as: biomechanical aspects, success rate, longevity and surgical-prosthetic planning. Literature review: Current and relevant references were selected in order to compare short dental implants to conventional ones. Several studies have highlighted the great importance of wide-diameter implants. Dental short implants have shown high predictability and success rates when some biomechanical aspects are taken into consideration. Conclusion: Placement of short dental implants is a viable treatment method for patients with decreased bone height.

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The aim of this study is to demonstrate through a case report, a proposed treatment for discolored teeth, with and without pulp vitality, by the technique of external and internal tooth bleaching with hydrogen peroxide to 35% Lase Peroxide Sensy (DMC) using Whitening Lase II Device (DMC), and a silicone guide (3M ESPE) in the palatine portion of the upper teeth. In this clinical case, the patient had darkened dental elements 11 and 22, and dissatisfaction with the coloring of other elements. It was observed that the techniques used and the materials chosen allowed for an excellent aesthetic result, with technical simplicity and low cost, and minimal occurrence of signs and symptoms

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Os 13 artigos reunidos neste livro foram primeiramente apresentados em encontro internacional sobre participação, democracia e políticas públicas na América Latina, realizado em 2013 na Faculdade de Ciências e Letras da Unesp. Para os organizadores da obra discutir o tema, principalmente no que concerne à transparência dos sistemas de gestão, é extrema importância para apontar direções para uma renovação política, articulações sociais e desenvolvimento socioterritorial. Eles explicam que a análise de marcos legais, fragilidades institucionais e prática autoritárias permitem enxergar o seu contrário e, com isso, aprimorar a prática de políticas públicas voltadas ao desenvolvimento de um país sustentado na democracia e na cidadania ativa. O livro é divido em quatro eixos temáticos. O inicial apresenta artigos que analisam a cidadania relacionada à saúde, gênero, prevenção ao abuso sexual e juventude. Abarca temas como o Sistema Único de Saúde, os movimentos e grupos feministas e abuso sexual. O seguinte destaca temas ligados à educação, também relacionados à cidadania, como o financiamento da educação e a educação em presídios paulistas. Desenvolvimento e combate às desigualdades sociais norteiam os estudos da terceira parte. São três artigos que tratam da complexidade da produção de políticas baseadas no diálogo entre pares institucionais, como representantes de governos e sociedade civil. O capítulo final é dedicado ao tema controle social e aperfeiçoamento da democracia. Os artigos abordam a questão do monitoramento das políticas e investimentos públicos por parte da sociedade civil.

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Pós-graduação em Ciência Florestal - FCA