Effect of Beverages and Mouthwashes on the Hardness of Polymers Used in Intraoral Prostheses

PurposeThe mechanical properties of acrylic resins used in intraoral prostheses may be altered by frequent exposure to liquids such as beverages and mouthwashes. This study aimed to evaluate the effect of thermocycling and liquid immersion on the hardness of four brands of acrylic resins commonly used in removable prostheses (Onda Cryl, QC-20, Classico, Lucitone).Materials and MethodsFor each brand of resin, seven specimens were immersed in each of six solutions (coffee, cola, red wine, Plax-Colgate, Listerine [LI], Oral B), and seven more were placed in artificial saliva (control). The hardness was tested using a microhardness tester before and after 5000 thermocycles and after 1, 3, 24, 48, and 96 hours of immersion. The results were analyzed using three-way repeated-measures ANOVA and Tukey's test (p < 0.05).ResultsThe hardness of the resins decreased following thermocycling and immersion in the solutions. Specimens immersed in cola and wine exhibited significant decreases in hardness after immersion for 96 hours, although the greatest significant decrease in hardness occurred in specimens immersed in LI. However, according to American Dental Association specification 12, the Knoop hardness of acrylic resins for intraoral prostheses should not be below 15. Thus, the median values of superficial hardness observed in most of the acrylic resins in this study are considered clinically acceptable.ConclusionsThe microhardness of polymers used for intraoral prostheses decreases following thermocycling. Among specimens immersed in beverages, those immersed in cola or wine experienced the greatest decrease in microhardness. Immersion of acrylic resins in LI significantly decreased the microhardness in relation to the initial value. Among the resins assessed, QC-20 exhibited the lowest initial hardness.

BIOMOLECULES EXTRACTED BY ATPS: PRACTICAL EXAMPLES

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

Radônio como indicador de contaminação de solos por hidrocarbonetos

Previous studies show that in areas contaminated by fuel spill (NAPL- non-aqueous phase liquids), from operational activities, transport and storage, it was possible to observe a significant decrease of ²²²Rn (radon) gas concentration in the soil, even a non-uniform distribution of this gas in top soil, even with a geological situation was practically homogeneous. These anomalies may be associated with the preference partitioning of radon in NAPLs. This work consists of applying ²²²Rn as an indicator for locating subsurface contamination by NAPLs in an area of the city of Rio Claro (SP) where, according to the “Survey of Contaminated and Rehabilitated Areas in the State of São Paulo (Environmental Sanitation and Technology Company - CETESB), there was, in the year 2007, groundwater contamination from leaks of liquid fuels. The challenges of this research are: Promulgate the use of a new tool with greater efficiency in obtaining results, in addition to generate less impact in half and have less expenditure; disseminate scientific culture promoting greater integration of C&T (culture & technology) between universities and businesses. The emanometric technique to estimate the location, number and interfacial area of NAPL in saturated and non-saturated zone, has the advantage of locating and determining plumes of free phase even when the amount of VOC's (Volatile Organic Compounds) that reaches the surface is low or non-existent. In addition, the measurement techniques ²²²Rn are quite developed. The results obtained show that, similar to the other studies, the 222Rn soil gas presents an anomalous behavior in the area bounded by NAPL plume, being possible to note a significant deficit in the concentration of the gas in spots where the saturation by NAPLs is still critical. Therefore it is concluded that this tool is really promising, but we must be careful to evaluate the initial conditions of the area, as well as the type of...

Comunicação de marcas de moda: nova proposta para a ação do Relações Públicas

This study has the objective of presenting a new suggestion to the public relations professional into the Brazilian fashion business, seeing that, besides promising and little explored, presents social-economic conditions that allow the profession actuation. For this, it has been deeply analyzed the social character of fashion history e its development parallel to the society historical and economic transformations, basing, then, the study of fashion history in Brazil. To understand contemporaneity and the relations which interlace on it, there were used two analyzes about nowadays social order, liquid pos-modernity, from Bauman; and the hypermodernity, from Lipovetsky. In this context, it‟s approached new ways of relating with marks and with products which, since their consumption, are prepared to posterior discard. In the accelerated scenario of marks and consumption, the human relations, more liquids and tenuous, create the urgent possibility of action from on communication professional, who knows to identify the consumers desires and foresee their needs, rendering the tenuous laces stronger and the relationships more solid. This is when the profession of public relations presents itself as a new proposal to create experiences and to tight the loose laces on the consumption era

Mapeamento geoestatístico da permeabilidade superficial no entorno do Ribeirão Claro: e simulação da possibilidade de sua contaminação

The evaluation of soil permeability throughout the weathering profile is one of the most important features to be considered in environmental studies. This study, developed from field testing and analysis of data obtained by geostatistical methods, aims at mapping the permeability around the Ribeirão Claro river. The intent is to simulate an accident with toxic liquids where soil permeability is of fundamental importance. Another purpose of the research was to determine the minimum time that, in the event of an accident, a possible contaminant to reach the water table level and be routed to the nearest drain, in this case, the Ribeirao V Claro river constitutes fundamental information. The studied area of approximately 4 km² is located within the UNESP-Rio Claro campus, consisting of colluvial soil from Fm. Rio Claro superimposed on residual soil of Fm. Corumbataí. The method used to determine the permeability is the concentric cylinders performed on a sampling grid with 64 points containing spacing of 5 meters EW and 10 meters NS. In the places of permeability tests were collected samples for laboratory determination of the percentage of fines. From particle size analysis was performed and analysis statistical and geostatistical on this data. The histogram was based on the statistical studies, and the semivariograms were based on geostatistical estimation methods. Based on the comparison between the maps and the data obtained, it was determined that the percentage of fines in colluvial surface soil has little influence on permeability, which the proximity to the Ribeirao Claro river, the eastern portion, a factor that influences the distribution of permeability values

Estudos das condições da disposição final de resíduos sólidos domiciliares no aterro sanitário de Cachoeira Paulista – SP

In this assignment, will be assessed the conditions of operation for the final disposal of household solid waste landfill in the city of Cachoeira Paulista-SP. The theme chosen for research is of great social importance therefore is directly related to the well-being of the people, sustainable development, environmental protection and public health. Everyone should be aware of the problems related to improper final disposal of solid waste of any kind. The objectives of the study were: analyse the conditions of operation of the landfill; verify the treatment technology of percolating liquids (slurry) generated in the landfill; examine whether the landfill obey the rules; which cities in the region depend on the disposal system, verify that there are flaws in the final destination of solid waste in the municipality and in the cities of the region. The research is primarily a bibliographic review, obtained by querying the database and virtual libraries. Technical visits were also held at the study site, to check spot the methodology employed in the operation of landfill This work concluded that for the period under study, the landfill was as a landfill site, therefore, in accordance with the rules of operation

Análise ultrassonográfica qualitativa e quantitativa da deglutição orofaríngea

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação do potencial biotecnológico de microorganismos da biodiversidade brasileira: biodegradação de herbicidas benzonitrilados

Pós-graduação em Química - IQ

Consumo de extrato hidrossolúvel de soja diminui a qualidade do tecido ósseo de ratos machos jovens: Bruna Rezende Silva Martins de Oliveira. -

Pós-graduação em Ciência Animal - FMVA

Síntese quimioenzimática do levetiracetam e análogos

Pós-graduação em Química - IQ

In vitro study of staining agents effects on optical properties of esthetic restorative materials

The authors have studied the effect of four staining agents on the optical properties of esthetic restorative materials through translucency tests. Two commercial brands of composite resins were used: Point 4 (Kerr) and Charisma (Heraeus-Kulzer). The liquids tested were: wine, cola, chlorhexidine solution and nicotine solution. The translucency was measured at different periods of time: P0 – before immersion (baseline), P1 - 1 h after immersion, P2 - 2 h after immersion and successively, P3 – 24 h after immersion up to a period of 7 weeks. ANOVA statistical analysis was applied to the data (p < 0.05). The results lead to the following conclusions: (1) Composite resins submitted to the tested immersion mediums were stained, (2) the lower percentage of translucency was observed for nicotine containing solution, (3) The percentage of translucency decreased with the period of immersion.

Dor orofacial e qualidade de vida de adultos

To determine the prevalence and intensity of orofacial pain in adults that participated in a health program at Ribeirão Preto. Methodology: The study was conducted by a self-administered questionnaire, with 19 questions in 99 people aged 18 to 66 years. The method used for data collection was the index Oral Impacton Daily Performances (OIDP), which evaluated the six months preceding the survey, pain experiences in the mouth, teeth or dentures and how these factors interfere with daily activities. Statistical analysis was performed using Epi Info version 3.4. Results: The majority of the adults who participated in this survey (52.5%) reported having an excellent or good oral health, reported having problems with their teeth (60.6%), no problems with the gums (77.8%), no bad taste in mouth (77.8%) or bad breath (77.8%). Among the participants of the study, 56.6% felt orofacial pain in the last six months and the pain were more frequently caused by cold or hot liquids (30.3%), spontaneous pain (17.2%), during the mouth opening (17.2%), pain in the face (13.1%) and ATM (13.1%). Regarding the severity rate, the highest proportion varied from mild to moderate. Conclusions: Even observing a low severity of orofacial pain, its prevalence was high, which probably has a negative effect on life quality of these people.

Análise de registros ortográficos de consoantes soantes no início da alfabetização

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

Microfluidic electronic tongue

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

Effect of temperature on salt-salt aqueous biphasic systems: manifestations of upper critical solution temperature

Water-miscible ionic liquids (ILs) may be salted out using kosmotropic salts such as potassium phosphate (K3PO4) to form salt-salt aqueous biphasic systems (ABS). The effect of temperature on these systems has been studied using phase diagrams and it is observed that the degree of binodal shift decreases (requiring lower IL and kosmotropic salt concentrations) with the increase of temperature following the trend [C(4)mim]Cl > [C(4)py]Cl > [C(4)mmim] Cl > [N-4444]Cl. This trend can be correlated with the decreasing hydrogen bonding abilities of each salt. The phase behavior was also interpreted on the basis of critical solution temperature behavior of pure aqueous ionic liquid solutions. Additionally, the distribution of alcohols in these systems was studied as a function of temperature and it was found that the distribution ratios did not change with changes in temperature. The Gibbs energy of transfer of a methylene group in these systems and correlation to tie-line length was also determined. It was concluded that while the miscibility of alcohols increases in the ILs with increasing temperature, phase divergence in the aqueous biphasic system decreases, and thus these competing forces tend to cancel each other out for small polar molecules. A comparison is provided for the response to temperature in the currently studied salt-salt systems and analogous ABS formed by the addition of hydrophilic polymers to kosmotropic salts (polymer-salt) or other polymers (polymer-polymer).