183 research outputs found

    Cephalometric assessment of the hyoid bone position in Oral Breathing Children

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    SummaryMaterial and Methods: because of its anatomical and functional relationship with the craniofacial complex, we assessed the cephalometry of the hyoid bone position in relation to the respiratory pattern of these 53 female children, with average age of 10 years; 28 of them are nasal breathers and 25 are oral breathers. Horizontal, vertical and angular cephalometric measures were used in order to determine the hyoid bone location. The Student “t” and the Pearson correlation tests were used in order to compare the groups and the variables.ResultsWe did not see statistically significant differences in mandible and hyoid bone positions and the respiratory pattern. In the hyoid triangle, the 0.40 correlation coeficient was significant between AA-ENP (distance between the Atlas vertebrae and the posterior nasal spine) and C3-H (distance between the third cervical vertebrae and the hyoid bone) showing a positive relation between the bony limits of the upper and lower air spaces. For cranial measures we have suggested a relationship between the hyoid bone position and the mandible morphology.ConclusionThe results led us o conclude that the hyoid bone keeps a stable position, probably in order to secure correct ratios in the airways, and it does not depend on the respiratory pattern

    Análise do coeficiente de variação em testes de resistência da união ao cisalhamento e tração

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    The coefficient of variation is a dispersion measurement that does not depend on the unit scales, thus allowing the comparison of experimental results involving different variables. Its calculation is crucial for the adhesive experiments performed in laboratories because both precision and reliability can be verified. The aim of this study was to evaluate and to suggest a classification of the coefficient variation (CV) for in vitro experiments on shear and tensile strengths. The experiments were performed in laboratory by fifty international and national studies on adhesion materials. Statistical data allowing the estimation of the coefficient of variation was gathered from each scientific article since none of them had such a measurement previously calculated. Excel worksheet was used for organizing the data while the sample normality was tested by using Shapiro Wilk tests (alpha = 0.05) and the Statistical Analysis System software (SAS). A mean value of 6.11 (SD = 1.83) for the coefficient of variation was found by the data analysis and the data had a normal distribution (p>;0.05). A range classification was proposed for the coefficient of variation from such data, that is, it should be considered low for a value lesser than 2.44; intermediate for a value between 2.44 and 7.94, high for a value between 7.94 and 9.78, and finally, very high for a value greater than 9.78. Such classification can be used as a guide for experiments on adhesion materials, thus making the planning easier as well as revealing precision and validity concerning the data.O Coeficiente de variação é uma medida de dispersão que independe da escala de unidades, permitindo comparação de resultados experimentais de variáveis diferentes. Seu cálculo é imprescindível em experimentos laboratoriais de adesão, pois a partir dele é possível verificar a precisão e confiabilidade do experimento. O objetivo deste trabalho foi avaliar e sugerir uma classificação do coeficiente de variação (CV) em experimentos in vitro que envolveram testes de resistência ao cisalhamento e / ou tração. Foram analisados 50 trabalhos de periódicos nacionais e internacionais, sendo que todos avaliaram a adesão em ensaios laboratoriais. Foram coletados em cada artigo dados estatísticos que permitiram estimar o coeficiente de variação, pois nenhum deles apresentava esta medida calculada. Os dados coletados foram organizados em Planilha Excel, sendo a normalidade da amostra testada pelo teste de Shapiro Wilk (alfa=0,05) utilizando o programa Statistical Analysis System (SAS). Pela análise dos dados, tendo os mesmos apresentados distribuição normal (p>;0,05) foi encontrado um CV médio de 6,11 com desvio-padrão de 1,83. A partir destes dados foram propostas faixas de classificação para o coeficiente de variação, ou seja, este coeficiente deve ser considerado baixo até um valor de 2,44; médio entre 2,44 - 7,94, alto entre 7,94 - 9.78 e muito alto acima de 9,78. Esta classificação poderá ser usada como guia para experimentos de adesão, facilitando o planejamento, revelando a precisão e validade dos dados

    Effect Of Etching Time And Light Source On The Bond Strength Of Metallic Brackets To Ceramic

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    This study evaluated the bond strength of brackets to ceramic testing different etching times and light sources for photo-activation of the bonding agent. Cylinders of feldspathic ceramic were etched with 10% hydrofluoric acid for 20 or 60 s. After application of silane on the ceramic surface, metallic brackets were bonded to the cylinders using Transbond XT (3M Unitek). The specimens for each etching time were assigned to 4 groups (n=15), according to the light source: XL2500 halogen light, UltraLume 5 LED, AccuCure 3000 argon laser, and Apollo 95E plasma arc. Light-activation was carried out with total exposure times of 40, 40, 20 and 12 s, respectively. Shear strength testing was carried out after 24 h. The adhesive remnant index (ARI) was evaluated under magnification. Data were subjected to two-way ANOVA and Tukey's test (α=0.05). Specimens etched for 20 s presented significantly lower bond strength (p0.05) were detected among the light sources. The ARI showed a predominance of scores 0 in all groups, with an increase in scores 1, 2 and 3 for the 60 s time. In conclusion, only the etching time had significant influence on the bond strength of brackets to ceramic.223245248Barghi, N., Fischer, D.E., Vatani, L., Effects of porcelain leucite content, types of etchants, and etching time on porcelaincomposite bond (2006) J Esthet Restor Dent, 18, pp. 47-52Nagayassu, M.P., Shintome, L.K., Uemura, E.S., Araújo, J.E., Effect of surface treatment on the shear bond strength of a resin-based cement to porcelain (2006) Braz Dent J, 17, pp. 290-295Shimada, Y., Yamaguchi, S., Tagami, J., Micro-shear bond strength of dual-cured resin cement to glass ceramics (2002) Dent Mater, 18, pp. 380-388Chen, J.H., Matsumura, H., Atsuta, M., Effect of different etching periods on the bond strength of a composite resin to a machinable porcelain (1998) J Dent, 26, pp. 53-58Guler, A.U., Yilmaz, F., Yenisey, M., Guler, E., Ural, C., Effect of acid etching time and a self-etching adhesive on the shear bond strength of composite resin to porcelain (2006) J Adhes Dent, 8, pp. 21-25Kasuya, K., Miyazaki, Y., Ogawa, N., Maki, K., Manabe, A., Itoh, K., Efficacy of experimental dual-cure resin cement for orthodontic direct bond system (2006) Orthod Waves, 65, pp. 107-111Meguro, D., Hayakawa, T., Kasai, K., Efficacy of using orthodontic adhesive resin in bonding and debonding characteristics of a calcium phosphate ceramic bracket (2006) Orthod Waves, 65, pp. 148-154Dall'igna, C.M., Marchioro, E.M., Spohr, A.M., Mota, E.G., Effect of curing time on the bond strength of a bracket-bonding system cured with a light-emitting diode or plasma arc light (2011) Eur J Orthod, 33, pp. 55-59Correr, A.B., Sinhoreti, M.A., Sobrinho, L.C., Tango, R.N., Schneider, L.F., Consani, S., Effect of the increase of energy density on Knoop hardness of dental composites light-cured by conventional QTH, LED and xenon plasma arc (2005) Braz Dent J, 16, pp. 218-224Cekic-Nagas, I., Egilmez, F., Ergun, G., The effect of irradiation distance on microhardness of resin composites cured with different light curing units (2010) Eur J Dent, 4, pp. 440-446Thind, B.S., Stirrups, D.R., Lloyd, C.H., A comparison of tungstenquartz- halogen, plasma arc and light-emitting diode light sources for the polymerization of an orthodontic adhesive (2006) Eur J Orthod, 28, pp. 78-82Filipov, I.A., Vladimirov, S.B., Residual monomer in a composite resin after light-curing with different sources, light intensities and spectra of radiation (2006) Braz Dent J, 17, pp. 34-38Park, J.K., Hur, B., Ko, C.C., García-Godoy, F., Kim, H.I., Kwon, Y.H., Effect of light-curing units on the thermal expansion of resin nanocomposites (2010) Am J Dent, 23, pp. 331-334Price, R.B., Labrie, D., Rueggeberg, F.A., Felix, C.M., Irraciance differences in the violet (405 nm) and blue (460 nm) spectral ranges among dental light-curing units (2010) J Esthet Restor Dent, 22, pp. 363-377Yen, T.W., Blackman, R.B., Baez, R.J., Effect of acid etching on the flexural strength of a feldspathic porcelain and a castable glass ceramic (1993) J Prosthet Dent, 70, pp. 224-233Reynolds, I.R., Composite filling materials as adhesives in orthodontics (1975) Br Dent J, 138, p. 83Rueggeberg, F., Contemporary issues in photocuring (1999) Compend Contin Educ Dent, (SUPPL.), pp. 4-15Olsen, M.E., Bishara, S.E., Boyer, D.B., Jakobsen, J.R., Effect of varying etching times on the bond strength of ceramic brackets (1996) Am J Orthod Dentofacial Orthop, 109, pp. 403-409Sant'anna, E.F., Monnerat, M.E., Chevitarese, O., Stuani, M.B., Bonding brackets to porcelain - in vitro study (2002) Braz Dent J, 3, pp. 191-196Canay, S., Hersek, N., Ertan, A., Effect of different acid treatments on a porcelain surface (2001) J Oral Rehabil, 28, pp. 95-10

    Study of the cephalometric standards of individuals with normal occlusion and prevalence of the malocclusion in the city of Rio de Janeiro, Rio de Janeiro, Brazil

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    ABSTRACT Objective: The accomplishment of this cephalometric objective to evaluate the face characteristics of this cefalometric work individuals had to the city of this cephalometric prevalence, as well as measure the objective of malocclusion. Methods: For this study, 531 sort of individuals of the masculine organizations of Rio de Janeiro had been submitted to the clinical chait of the course of Master in Orthodontics of the Center Research Leopold Mandic, of which if it got prevalence of malocclusion. Results: Of this sample, it was observed that 22 individuals with normal occlusion and that if they had never submitted the orthodontic treatment. In these patients they had been made taken from normal head in lateral cephalometric radiographs and evaluated the cephalometrics largeness: SNA, SNB, ANB, Axle “Y”, NS.Go-Me, FMA, FMIA, IMPA, 1.NA, 1- NA, 1.NB, 1-NB, 1.1, 1.SN, 1.Go-Gn, SN.PLO, AO-BO, Line H, Z angle, P-NB, AFA, AFP and IAF. The gotten date had been submitted to the analysis with a level of significance of 5% (p< 0.05) and used descriptive statistics and the error of Dalbergh. The results showed that of the total of the evaluated sample, the malocclusion of 44.3% of Classroom I; 29.5% of Classroom II; 17.2% of Classroom III and 9.2% of normal occlusion. Conclusion: The individuals with normal occlusion of the city of Rio De Janeiro had presented equal cephalometric characteristics with many standard measures described in literature, except for the superior incisor that were presented vestibulate and the well inclined inferior incisor for vestibular contest

    Prognostic factors and historical trends in the epidemiology of candidemia in critically ill patients: an analysis of five multicenter studies sequentially conducted over a 9-year period

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    To describe temporal trends in the epidemiology, clinical management and outcome of candidemia in intensive care unit (ICU) patients.This study was a retrospective analysis of 1,392 episodes of candidemia in 647 adult ICU patients from 22 Brazilian hospitals. the characteristics of candidemia in these ICU patients were compared in two periods (2003-2007, period 1; 2008-2012, period 2), and the predictors of 30-day mortality were assessed.The proportion of patients who developed candidemia while in the ICU increased from 44 % in period 1 to 50.9 % in period 2 (p = 0.01). Prior exposure to fluconazole before candidemia (22.3 vs. 11.6 %, p < 0.001) and fungemia due to Candida glabrata (13.1 vs. 7.8 %, p = 0.03) were more frequent in period 2, as was the proportion of patients receiving an echinocandin as primary therapy (18.0 vs. 5.9 %, p < 0.001). the 30-day mortality rate decreased from 76.4 % in period 1 to 60.8 % in period 2 (p < 0.001). Predictors of 30-day mortality by multivariate analysis were older age, period 1, treatment with corticosteroids and higher APACHE II score, while treatment with an echinocandin were associated with a higher probability of survival.We found a clear change in the epidemiology and clinical management of candidemia in ICU patients over the 9-year period of the study. the use of echinocandins as primary therapy for candidemia appears to be associated with better outcomes.MSDPfizerUnited MedicalUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilHosp Serv Publ Estadual São Paulo, São Paulo, BrazilIrmandade Santa Casa de Misericordia Porto Alegre, Porto Alegre, RS, BrazilUniv Fed Ciencias Sau Porto Alegre, Porto Alegre, RS, BrazilUniv Fed Parana, BR-80060000 Curitiba, Parana, BrazilUniv Fed Rio de Janeiro, Rio de Janeiro, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilWeb of Scienc

    Shear bond strength of metallic orthodontic brackets bonded to enamel prepared with self-etching primer

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    The aim of this study was to determine the shear bond strength of different composites and to determine the adhesive remnant index (ARI) of metallic brackets bonded to enamel prepared with Transbond Plus Self-Etching Primer (TPSEP). Forty human premolars were divided into four equal groups. In group 1 (control), the Transbond XT was conventionally used. In groups 2-4, the TPSEP was used before bonding with Transbond XT, Z-100, and Concise Orthodontic, respectively. After the bonding, the samples were stored in distilled water at 37 degrees C for 24 hours. The brackets were debonded using a universal testing machine at a crosshead speed of 0.5 mm/ min. The shear bond strength (MPa) for group 1 (control), group 2 JPSEP + Transbond XT), group 3 JPSEP + Z-100), and group 4 JPSEP + Concise Orthodontic) were of 6.43, 4.61, 4.74, and 0.02, respectively. Group 1 was statistically superior to other groups (P .05), although both were statistically superior to group 4 (P < .05). According to the ARI evaluation, most of the failures involved the bracket/composite interface (groups 1 and 2) as well as the enamel/composite interface (groups 3 and 4). The Transbond XT conventionally bonded showed better adhesion results than Transbond XT, Z-100, and Concise Orthodontic after using Transbond Plus Self-Etching Primer.75584985

    Prognostic factors and historical trends in the epidemiology of candidemia in critically ill patients: an analysis of five multicenter studies sequentially conducted over a 9-year period (vol 40, pg 1489, 2014)

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    Universidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilHosp Serv Publ Estadual São Paulo, São Paulo, BrazilIrmandade Santa Casa de Misericordia Porto Alegre, Porto Alegre, RS, BrazilUniv Fed Ciencias Saude Porto Alegre, Porto Alegre, RS, BrazilUniv Fed Parana, BR-80060000 Curitiba, Parana, BrazilUniv Fed Rio de Janeiro, Rio de Janeiro, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilWeb of Scienc

    Cephalometric assessment of the hyoid bone position in oral breathing children

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    MATERIAL AND METHODS: because of its anatomical and functional relationship with the craniofacial complex, we assessed the cephalometry of the hyoid bone position in relation to the respiratory pattern of these 53 female children, with average age of 10 years; 28 of them are nasal breathers and 25 are oral breathers. Horizontal, vertical and angular cephalometric measures were used in order to determine the hyoid bone location. The Student t and the Pearson correlation tests were used in order to compare the groups and the variables. RESULTS: We did not see statistically significant differences in mandible and hyoid bone positions and the respiratory pattern. In the hyoid triangle, the 0.40 correlation coeficient was significant between AA-ENP (distance between the Atlas vertebrae and the posterior nasal spine) and C3-H (distance between the third cervical vertebrae and the hyoid bone) showing a positive relation between the bony limits of the upper and lower air spaces. For cranial measures we have suggested a relationship between the hyoid bone position and the mandible morphology. CONCLUSION: The results led us o conclude that the hyoid bone keeps a stable position, probably in order to secure correct ratios in the airways, and it does not depend on the respiratory pattern.MATERIAL E MÉTODOS: em função das relações anatomofuncionais do osso hióide com o complexo craniofacial, realizou-se avaliação cefalométrica da posição do osso hióide em relação ao padrão respiratório. A amostra consistiu de 53 crianças, gênero feminino, com idades médias de 10 anos, sendo 28 respiradoras nasais e 25, bucais. As medidas cefalométricas horizontais, verticais e angulares foram utilizadas com a finalidade de determinar a posição do osso hióide. Estabeleceu-se uma comparação entre os grupos por meio do teste t de student, bem como correlação de Pearson entre as variáveis. RESULTADOS: Observou-se que não ocorreram diferenças estatísticas significativas para a posição mandibular e posição do osso hióide e o tipo do padrão respiratório. No Triângulo Hióideo, o coeficiente de correlação de 0,40 foi significativo entre AA-ENP (distância entre vértebra atlas e espinha nasal posterior) e C3-H (distância entre a terceira vértebra cervical e osso hióide) demonstrando uma relação positiva entre os limites ósseos do espaço aéreo superior e inferior. Para as medidas cranianas sugeriu-se uma relação entre a posição do osso hióide com a morfologia mandibular. CONCLUSÃO: Os resultados permitiram concluir que o osso hióide mantém uma posição estável, provavelmente, para garantir as proporções corretas das vias aéreas e não depende do padrão respiratório predominante.475
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