964 resultados para class III cavities


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Objectives: To study the nanoleakage pattern in the dentin hybrid layer by using different dentin adhesives. The null hypotheses tested in this study were: 1) dentin conditioning time does not affect nanoleakage within the hybrid layer; 2) the type of dentin adhesive used does not affect nanoleakage. Methods: Standardized Class V cavities were prepared in 30 intact human molars on the buccal and lingual surfaces. The specimens were randomly assigned to 2 total-etch dentin adhesives (OptiBond SOLO Plus [OPS, Kerr] and One-Step [ONS, BISCO Inc]) and 2 self-etch dentin adhesives (Clearfil SE Bond [CSE, Kuraray] and Adper Prompt L-Pop [APL, 3M ESPE]). The specimens were etched or conditioned for 15 seconds, 30 seconds or 60 seconds. Upon restoration of the Class V cavities with the proprietary resin composite, the specimens were isolated with nail polish except for a 2.0-mm rim around the restoration, and they were immersed in 50 wt% ammoniacal silver nitrate solution (pH=9.5) for 24 hours followed by 8 hours of immersion in photo-developing solution to reduce the silver ions to metallic silver. The specimens were fixed, dehydrated and processed for FESEM and TEM. Silver penetration was measured along the cervical wall, and data were analyzed with Kruskal-Wallis non-parametric tests at a significance level of 95%. Results: There were no statistically significant differences among the experimental groups for the factor conditioning time (p>0.926). There were significant differences for the variable dentin adhesive (p<0.0001). The least amount of nanoleakage within the hybrid layer occurred with CSE, while ONS resulted in the greatest penetration of silver ions. The adhesives OPS and APL ranked in the intermediary subset. Under TEM, all adhesives resulted in some degree of nanoleakage within the hybrid layer. Both spotted/reticular and water-tree nanoleakage patterns were observed. Significance: Longer conditioning times did not increase nanoleakage within the hybrid layer. Nanoleakage varied with the type of adhesive used.

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Purpose: To evaluate the accuracy of Image Tool Software 3.0 (ITS 3.0) to detect marginal microleakage using the stereomicroscope as the validation criterion and ITS 3.0 as the tool under study.Materials and Methods: Class V cavities were prepared at the cementoenamel junction of 61 bovine incisors, and 53 halves of them were used. Using the stereomicroscope, microleakage was classified dichotomously: presence or absence. Next, ITS 3.0 was used to obtain measurements of the microleakage, so that 0.75 was taken as the cut-off point, and values equal to or greater than 0.75 indicated its presence, while values between 0.00 and 0.75 indicated its absence. Sensitivity and specificity were calculated by point and given as 95% confidence interval (95% CI).Results: The accuracy of the ITS 3.0 was verified with a sensitivity of 0.95 (95% CI: 0.89 to 1.00) and a specificity of 0.92 (95% CI: 0.84 to 0.99).Conclusion: Digital diagnosis of marginal microleakage using ITS 3.0 was sensitive and specific.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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No presente trabalho foi estudada a ocorrência, distribuição e morfologia de glândulas tegumentares do abdome em Exomalopsis auropilosa Spinola, Centris fuscata Lepeletier, Epicharis flava Friese e Xylocopa (Neoxylocopa) suspecta Moure & Camargo. Os resultados mostraram a ocorrência de glândulas epiteliais (classe I) e unicelulares (classe III) com distribuição dorsal (tergais) e ventral (esternais) sem que se pudesse caracterizar um padrão relacionável com a posição filogenética ou grau de sociabilidade. No entanto, verificou-se uma tendência para maior número de glândulas em espécies com algum grau de sociabilidade como E. auropilosa e X. suspecta.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Este é um primeiro relato sobre a presença de células glandulares no tegumento lateral do mesotórax de abelhas da subfamília Meliponinae. Trata-se de células glandulares de classe III que estão presentes em rainhas, operárias e machos. As glândulas são mais desenvolvidas nas rainhas que nas operárias e nestas mais que nos machos.

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Purpose: Existing composite restorations on teeth are often remade prior to the cementation of fixed dental prostheses. The aim of this study was to evaluate the effect of static and cyclic loading on ceramic laminate veneers adhered to aged resin composite restorations.Materials and Methods: Eighty sound maxillary incisors were collected and randomly divided into four groups: group 1: control group, no restorations; group 2: two Class III restorations; group 3: two Class IV restorations; group 4: complete composite substrate. Standard composite restorations were made using a microhybrid resin composite (Anterior Shine). Restored teeth were subjected to thermocycling (6000 cycles). Window preparations were made on the labial surface of the teeth for ceramic laminate fabrication (Empress II). Teeth were conditioned using an etch-and-rinse system. Existing composite restorations representing the aged composites were silica coated (CoJet) and silanized (ESPE-Sil). Ceramic laminates were cemented using a bis-GMA-based cement (Variolink Veneer). The specimens were randomly divided into two groups and were subjected to either static (groups 1a, 2a, 3a, 4a) or cyclic loading (groups 1b, 2b, 3b, 4b). Failure type and location after loading were classified. Data were analyzed using one-way ANOVA and Tukey's test.Results: Significantly higher fracture strength was obtained in group 4 (330 +/- 81 N) compared to the controls in group 1 (179 +/- 120 N) (one-way ANOVA, p < 0.05). Group lb survived a lower mean number of cyclic loads (672,820 cycles) than teeth of groups 2b to 4b (846x10(3) to 873x10(3) cycles). Failure type evaluation after the fracture test showed predominantly adhesive failures between dentin and cement, but after cyclic loading, more cohesive fractures in the ceramic were seen.Conclusion: Ceramic laminate veneers bonded to conditioned aged composite restorations provided favorable results. Surface conditioning of existing restorations may eliminate the necessity of removing aged composite restorations.

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INTRODUÇÃO: nesse estudo cefalométrico retrospectivo, analisou-se a influência da anquilose intencional de caninos decíduos em pacientes com má oclusão de Classe III e mordida cruzada anterior, nos estágios de dentição decídua e mista precoce, tratados com expansão ortopédica da maxila, seguida de tração reversa. MÉTODOS: foram utilizadas telerradiografias em norma lateral de 40 pacientes, divididos em 2 grupos pareados por idade e sexo. O Grupo Anquilose foi constituído de 20 pacientes (10 meninos e 10 meninas) tratados com anquilose induzida e que apresentavam as idades médias inicial e final, respectivamente, de 7a 4m e 8a 3m, e o tempo médio de tração reversa de 11 meses. O Grupo Controle, composto de 20 pacientes (10 meninos e 10 meninas) tratados sem anquilose induzida e que apresentavam as idades médias inicial de 7a 8m e final de 8a 7m, e tempo médio de tração reversa de 11 meses. Foram empregadas as análises de Variância a dois critérios e de Covariância para comparar as variáveis cefalométricas inicial e final e as alterações de tratamento entre os grupos. RESULTADOS: segundo os resultados, as variáveis que evidenciaram as mudanças de tratamento significativas entre os grupos confirmaram que o procedimento de anquilose intencional potencializou a resposta sagital das bases apicais (Pg-NPerp) e aumentou os ângulos de convexidade facial (NAP e ANB). CONCLUSÃO: o protocolo envolvendo a anquilose intencional de caninos decíduos potencializou a resposta sagital das bases apicais.

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Foram estudadas a ocorrência e a morfologia de glândulas tegumentares presentes no abdome de fêmeas de Melissoptila richardiae. Os resultados mostram que nesta espécie, células glandulares da classe III são encontradas de duas formas: isoladas nos tergitos e esternitos III e IV e formando um aglomerado de unidades glandulares bilateralmente, entre os segmentos III e IV, os quais liberam seu produto de secreção em um reservatório originado a partir da membrana intersegmental. Os resultados sugerem que o produto secretado é lipídico e, provavelmente volátil.

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A pesquisa teve como objetivo determinar as forças de mordida de 73 indivíduos, por meio de um gnatodinamômetro. Os pacientes eram portadores de próteses parciais removíveis inferiores classes I, II ou III. A arcada antagonista era prótese, parcial removível ou fixa, ou total. Os resultados permitiram concluir que: as selas de extremidade livre, principalmente em suas posições extremas, conduziram a forças de mordida muito baixas; o envolvimento de prótese total, também, conduziu a forças de mordida baixas; o sexo masculino alcançou valores maiores que o feminino; com prótese parcial removível classe III, os dentes naturais molares e pré-molares desenvolveram valores maiores do que com classes I e II.

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Este estudo avaliou a ocorrência de más oclusões esqueléticas apresentadas pelos pacientes do Centro de Pesquisa e Tratamento das Deformidades Bucofaciais (CEDEFACE), na cidade de Araraquara, SP, Brasil. Foram avaliados prontuários de 381 pacientes com deformidades dentoesqueléticas, que fizeram tratamento combinado ortodôntico-cirúrgico no período entre 2000 e 2006. Após a seleção da amostra (método de conveniência), baseado nos dados da documentação pré e pós-cirúrgica, o número de pacientes foi reduzido para 171. Para classificação do levantamento, considerou-se a discrepância ântero-posterior (Classe I, II e III), raça, idade, gênero, ausência ou presença de assimetria, excesso vertical maxilar e biprotrusão maxilar, além de determinar em qual base óssea o procedimento cirúrgico foi realizado. As documentações dos pacientes foram analisadas por um examinador previamente calibrado pelo processo de repetição até que o método fosse considerado adequado (correlação intraclasse >0,94). A idade média dos pacientes foi de 23,59 anos (DP 6,93), a maioria do gênero feminino (102 pacientes) e leucoderma (160 pacientes). A má oclusão mais prevalente foi a Classe III (81 pacientes). A assimetria, o excesso maxilar vertical e biprotrusão maxilar estavam presentes em 54, 33, e 7 pacientes, respectivamente. Na maioria dos casos, as cirurgias para correção de deformidades dentoesqueléticas foram combinadas, envolvendo os dois maxilares. Com base nos resultados, conclui-se que a Classe III foi a deformidade esquelética mais prevalente e a Classe I a menos prevalente. em geral, a prevalência de deformidades esqueléticas foi maior entre as mulheres e a maioria dos pacientes apresentou uma combinação de problemas maxilares e mandibulares, o que interfere diretamente na decisão sobre o plano de tratamento mais adequado. Houve uma maior incidência de assimetria na Classe III esquelética; o excesso vertical ocorreu de forma semelhante na Classe II e III e a biprotrusão teve baixa incidência entre as más oclusões avaliadas.

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OBJECTIVE: To assess the hemodynamic and vasodilating effects of milrinone lactate (ML) in patients with dilated cardiomyopathy (DCM) and New York Heart Association (NYHA) class III and IV heart failure. METHODS: Twenty patients with DCM and NYHA class III and IV heart failure were studied. The hemodynamic and vasodilating effects of ML, administered intravenously, were evaluated. The following variables were compared before and during drug infusion: cardiac output (CO) and cardiac index (CI); pulmonary capillary wedge pressure (PCWP); mean aortic pressure (MAP); mean pulmonary artery pressure (MPAP); mean right atrial pressure (MRAP); left ventricular systolic and end-diastolic pressures (LVSP and LVEDP, respectively); peak rate of left ventricular pressure rise (dP/dt); systemic vascular resistance (SVR); pulmonary vascular resistance (PVR); and heart rate (HR). RESULTS: All patients showed a significant improvement of the analysed parameters of cardiac performance with an increase of CO and CI; a significant improvement in myocardial contractility (dP/dt) and reduction of the LVEDP; PCWP; PAP; MAP; MRAP; SVR; PVR. Were observed no significant increase in HR occurred. CONCLUSION: Milrinone lactate is an inotropic dilating drug that, when administered intravenously, has beneficial effects on cardiac performance and myocardial contractility. It also promotes reduction of SVR and PVR in patients with DCM and NYHA class III and IV of heart failure.

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The purpose of this study was to evaluate the influence of intrapulpal pressure and dentin depth on bond strengths of an etch-and-rinse and a self-etching bonding agent to dentin in vitro and in vivo. Twenty-four pairs of premolars were randomly divided into four groups (n = 6) according to the dentin bonding agent, Single Bond and Clearfil SE Bond, and intrapulpal pressure, null or positive. Each tooth of the pair was further designated to be treated in vivo or in vitro. The intrapulpal pressure was controlled in vivo by the delivery of local anesthetics containing or not a vasoconstrictor, while in vitro, it was achieved by keeping the teeth under hydrostatic pressure. Class I cavities were prepared and the dentin bonding agents were applied followed by incremental resin restoration. For the teeth treated in vitro, the same restorative procedures were performed after a 6 month-storage period. Beams with I mm 2 cross-sectional area were prepared and, microtensile tested. Clearfil SE Bond was not influenced by any of the variables of the study, while bond strengths produced in vitro were significatly higher for Single Bond. Overall, lower bond strengths were produced in deep dentin, which reached statistical significance when Single Bond was applied under physiological or simulated intrapulpal pressure. In conclusion, in vitro bonding may overestimate the immediate adhesive performance of more technique-sensitive dentin bonding systems. The impact of intrapulpal pressure on bond strength seems to be more adhesive dependent than dentin morphological characteristics related to depth. (C) 2007 Wiley Periodicals, Inc.

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Objective: the purpose of this study was to verify if the application of the Nd:YAG laser following pretreatment of dentin with adhesive systems that were not light cured in class V cavities and were prepared with Er:YAG laser would promote better sealing of the gingival margins when compared to cavities prepared the conventional way. Background Data: Previous studies had shown that the pretreatment of dentin with laser irradiation after the application of an adhesive system is efficient in achieving higher shear bond and tensile bond strength. Materials and Methods: Er:YAG laser (Kavo-Key, Germany) with 350 mJ, 4 Hz, and 116.7 J/cm(2) was used for cavity preparation. The conventional preparation was made with diamond bur mounted in high-speed turbine. Dentin treatment was accomplished using an Nd:YAG laser (Pulse Master 1000, ADT. USA) at 60 mJ, 10 Hz, and 74.65/cm(2) following application of the adhesive system. The cavities were stored with Single Bond/Z100 and Prime & Bond NT/TPH. Eighty bovine incisors were used, and class V preparations were done at buccal and lingual surfaces divided into eight groups: (1) Er:YAG preparation + Prime & Bond NT + TPH; (2) Er:YAG preparation + Single Bond + Z100; (3) Er:YAG preparation + Single Bond + Nd:YAG + Z100; (4) Er:YAG preparation + Prime & Bond NT + Nd:YAG + TPH; (5) conventional preparation + Prime & Bond NT + TPH; (6) conventional preparation + Single Bond + Z100; (7) conventional preparation + Single Bond + Nd:YAG + Z100; (8) conventional preparation + Prime & Bond NT + Nd:YAG + TPH. All specimens were thermocycled for 300 full cycles between 5 degreesC +/- 2 degreesC and 55 degreesC +/- 2 degreesC (dwell time of 30 sec), and stored in 50% silver nitrate solution for 24 h soaked in photodeveloping solution and exposed to fluorescent light for 6 h. After this procedure, the specimens were sectioned longitudinally in 3 portions and the extension of microleakage at the gingival wall was determined following a criteria ranging from 0 to 4 using scanning electron microscopy (SEM). The medium portion sectioned of each specimen was polished and prepared for nanoleakage avaliation by SEM. Results: Kruskall-Wallis and Miller statistical tests determined that group 3 presented less microleakage and nanoleakage. Conclusion: Application of the Nd:YAG laser following pretreatment of dentin with adhesive Single Bond non-photocured Single Bond adhesive in cavities prepared with Er:YAG promote better sealing of the gingival margins.

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The aim of this study was to evaluate the hypothesis that low-level laser therapy (LLLT) 688 nm and 785 nm accelerate dentin barrier formation and repair process after traumatic pulp exposure. The sample consisted of 45 premolars of capuchin monkeys (Cebus apella) with pulp exposure Class V cavities. All premolars were treated with calcium hydroxide (Ca(OH)(2)), divided in groups of 15 teeth each, and analyzed on 7(th), 25(th), and 60(th) day. Group GI - only Ca(OH)(2), GIF- laser 688 nm, and GIII - laser 785 nm. Laser beam was used in single and punctual dose with the parameters: continuous, 688 nm and 785 nm wavelength, tip's area of 0.00785 cm(2), power 50 mW, application time 20 s, dose 255 J/cm(2), energy 2 J. Teeth were capped with Ca(OH)(2), Ca(OH)(2) cement and restored with amalgam. All groups presented pulp repair. on 25(th) day the thickness of the formed dentin barrier was different between the groups GI and GII (p < 0.05) and between groups GI and GIII (p < 0.01). on 60(th) day there was difference between GI and GIII (p < 0.01). It may be concluded that, LLLT 688 nm and 785 nm accelerated dentin barrier formation and consequently pulp repair process, with best results using infrared laser 785 nm. (c) 2009 by Astro Ltd. Published exclusively by WLLEY-VCH Verlag GmbH & Co. KGaA