Effect of intrinsic nanoparticle pigmentation on the color stability of denture base acrylic resins

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

Color degradation of acrylic resin denture teeth as a function of liquid diet: ultraviolet-visible reflection analysis

The effect of different beverages on acrylic resin denture teeth color degradation is evaluated. Ten acrylic resin denture teeth brands were evaluated: Art Plus (AP), Biolux (BX), Biotone IPN (BI), Magister (MG), Mondial 6 (MD), Premium 6 (PR), SR Vivodent PE (SR), Trilux (TR), Trubyte Biotone (TB), and Vipi Dent Plus (VP). Teeth were immersed in staining solutions (coffee, cola, and orange juice) or artificial saliva (control) (n = 6) for 1, 7, 15, or 30 days. Specimen colors were evaluated spectrophotometrically based on the Commission Internationale d'Eclairage L*a*b* system. Color differences (Delta E) were calculated between the baseline and post-staining results. Data were evaluated by analysis of variance and Tukey test (alpha = 0.05). BI (1.82 +/- 0.95) and TR (1.78 +/- 0.72) teeth exhibited the greatest Delta E values, while BX (0.88 +/- 0.43) and MD (1.09 +/- 0.44) teeth were the lowest, regardless of solution and measurement period, and were different from BI and TR teeth (P < 0.05). Cola and coffee promoted higher denture teeth color alterations than orange juice and saliva (P < 0.05). Saliva generated the lowest denture teeth color alterations. Greater immersion times caused higher denture teeth color changes. The lifespan of removable dentures and the aesthetic satisfaction of several edentulous patients may be increased with the use of stain-resistant artificial denture teeth. (C) The Authors.

Mineral loss and color change of enamel after bleaching and staining solutions combination

Pigments of food and beverages could affect dental bleaching efficacy. The aim of this investigation was to evaluate color change and mineral loss of tooth enamel as well as the influence of staining solutions normally used by adolescent patients undergoing home bleaching. Initial hardness and baseline color were measured on enamel blocks. Specimens were divided into five groups (n = 5): G1 (control) specimens were kept in artificial saliva throughout the experiment (3 weeks); G2 enamel was exposed to 10% carbamide peroxide for 6 h daily, and after this period, the teeth were cleaned and stored in artificial saliva until the next bleaching session; and G3, G4, and G5 received the same treatments as G2, but after bleaching, they were stored for 1 h in cola soft drink, melted chocolate, or red wine, respectively. Mineral loss was obtained by the percentage of hardness reduction, and color change was determined by the difference between the data obtained before and after treatments. Data were subjected to analysis of variance and Fisher's test (a = 0.05). G3 and G5 showed higher mineral loss (92.96 +/- 5.50 and 94.46 +/- 1.00, respectively) compared to the other groups (p = 0.05). G5 showed high-color change (9.34 +/- 2.90), whereas G1 presented lower color change (2.22 +/- 0.44) (p = 0.05). Acidic drinks cause mineral loss of the enamel, which could modify the surface and reduce staining resistance after bleaching. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)

Clinical Trial Evaluating Color Change and Tooth Sensitivity Throughout and Following In-office Bleaching

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

All-loop infrared-divergent behavior of most-subleading-color gauge-theory amplitudes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Bio-Optical Properties of the Inner Continental Shelf off Santos Estuarine System, Southeastern Brazil, and their Implications for Ocean Color Algorithm Performance

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

Efeitos da interação e soluções utilizadas na prevenção da formação do precipitado originado pela interação do hipoclorito de sódio e do diglunato de clorexidina e a repercursão sobre a resistência de união de cimento obturador na dentina do canal radicular

Pós-graduação em Odontologia - FOAR

Risco de desordens músculo-esqueléticas nos membros superiores de graduandos de Odontologia

Este estudo teve por objetivo avaliar o risco de desenvolvimento de desordens músculo-esqueléticas nos membros superiores de graduandos de Odontologia considerando as variáveis sexo, tipo de procedimento clínico executado, região da boca tratada e prática do trabalho a quatro mãos. Foram avaliados alunos, de ambos os sexos, matriculados no oitavo semestre do curso de graduação da Faculdade de Odontologia de Araraquara - UNESP. Foram efetuadas tomadas fotográficas durante a realização de 283 procedimentos clínicos, utilizando-se máquina fotogrática digital. Para análise das fotografias, utilizou-se o programa Image Tool. As posturas de trabalho adotadas por cada estudante na sua atuação como “operador” foram observadas pelo método RULA (Rapid Upper Limb Assessment), o qual inclui o uso de um diagrama de análise de postura do indivíduo e três tabelas de escores que permitem a avaliação da exposição aos fatores de risco para o desenvolvimento de desordens músculo-esqueléticas. As fotografias foram analisadas por um professor da área de ergonomia calibrado (_=0,91). Para cada procedimento foi atribuído um escore de risco final. Os procedimentos executados foram classificados em duas grandes categorias: procedimentos preparatórios e procedimentos restauradores/reabilitadores. Os dados de risco de desordens músculoesqueléticas nos membros superiores foram apurados, e sua prevalência foi estimada por ponto e por intervalo de confiança de 95%. O estudo da associação do risco de desordens músculo-esqueléticas às variáveis de interesse foi realizado por meio do Teste de Qui-quadrado (_ 2). O nível de significância adotado foi de 5%. Observou-se que na maioria dos procedimentos executados o risco de desordens músculo-esqueléticas segundo a classificação... (Resumo completo, clicar acesso eletrônico abaixo)

Reassessment of the potential applications of Eu3+-doped Y2O3 photoluminescent material in ceramic powder form

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

Emergetic ternary diagrams: five examples for application in environmental accounting for decision-making

In a recent paper, "A combined tool for environmental scientists and decision makers: ternary diagrams and emergy accounting." [Giannettti BF, Barrella FA, Almeida CMVB. A combined tool for environment scientists and decision makers: ternary diagrams and emergy accounting. J Clean Prod, in press http://dx.doi.org/10.1016/j.jclepro.2004.09.002] Ternary diagrams were proposed as a graphical tool to assist emergy analysis. The graphical representation of the emergy accounting data makes it possible to compare processes and systems with and without ecosystem services, to evaluate improvements and to follow the system performance over time. The graphic tool is versatile and adaptable to represent products, processes, systems, countries, and different periods of time.The use and the versatility of ternary diagrams for assisting in performing emergy analyses are illustrated by means of five examples taken from the literature, which are presented and discussed. It is shown that emergetic ternary diagram's properties assist the assessment of the system of the system efficiency, its dependance upon renewable and non-renewable inputs and the environmental support for dilution and abatement of process emissions. With the aid of ternary diagrams, details such as the interaction between systems and between systems and the environment are recognized and evaluated. Such a tool for graphical analysis allows a transparent presentation of the results and can serve as an interface between emergy scientists and decision makers, provided the meaning of each line in the diagram is carefully explained and understood. (c) 2005 Elsevier Ltd. All rights reserved.

Influence of nanoparticles on color stability, microhardness, and flexural strength of acrylic resins specific for ocular prosthesis

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

Estudo da tratabilidade de água pluvial utilizando coagulante natural a base de tanino visando fins não potáveis

This paper aimed to study the treatability of rainwater collected in Rio Claro, SP, using natural coagulant tannin based. The tannin was compared with other too primary coagulants, namely ferric chloride and corn starch. Assays were performed in laboratory scale using equipment known as Jarteste and aimed to study the conditions most suitable dosage and coagulation pH. First tests were conducted to compare the coagulating and determination of the conditions to be used in the following tests, taking as a criterion the greatest efficiency for water treatment. Also performed were performed tests to construct the tannin coagulation diagram, using the optimal concentration found in the previous phase, by varying the dosage of coagulant and the pH of clotting in order to determine the isoefficiency regions for apparent color and turbidity. Finally, tests were performed cyclically filtration with filter paper. Preliminary tests indicated that the vegetable tannin concentration 3% (m/m) from the commercial solution was presented the best set of results (84.3% removal of apparent color and 82.51% removal of turbidity) compared to ferric chloride (66.25% removal efficiency and apparent color of turbidity 67.82%) and starch (73.68% removal efficiency apparent color and turbidity to 67.19%). The coagulation diagrams indicate that the best region to work with vegetable tannin 3% is where the coagulant dosage ranges from 15 mg/L to about 37.5 mg/L and coagulation pH ranging from about 6.5 to 7.5. The cyclic filtration showed to be not efficient for the best dosage of coagulant, due to the process of clogging of the filter paper, but proved to be efficient for other dosages. Thus, for the waters studied, the results indicate that the natural coagulant based tannin is an alternative to conventional coagulants, possessing benefits of technical and environmental

Color alteration, hydrogen peroxide diffusion, and cytotoxicity caused by in-office bleaching protocols

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

Correlación entre diferentes métodos de evaluación de color en el clareamiento dental. Correlation between different methods for co

The aim of this study was to evaluate the correlation of color change on bleaching tooth through delta E (ΔE) by the spectrophotometer Spectroshade (SS) and digital program Scanwhite (SW). Methods: 25 patient volunteers were recruited from Operative Dentistry at Universidad de Chile Dental School, between 18 to 30 years, with good oral hygiene. Exclusion criteria: Previous experienced tooth bleaching, anterior restorations, cervical lesions, pain dental, pregnant patient, stained teeth, malposition of the teeth and periodontal pathology. The bleaching was made in two sessions with three different bleaching systems which were randomly. The assessment of color change through ΔE was made on the two upper central incisors (N=50) by the SS and SW. The color in the same teeth were measured before (T0) and after (T1) of the bleaching treatment. Data were analyzed using test Spearman correlation coefficient (Rho) with a significant level of 95%. Results: The results showed a positive and significant correlation (0.676), with a statistically significant difference (p<0.05). Conclusion: There is correlation in the measurement of color change on bleaching tooth by SS and SW.