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Passo Fundo, Brazil

The University of Passo Fundo , also known as UPF, is a Brazilian private university. Founded in 1968, it is located in the city of Passo Fundo, in the state of Rio Grande do Sul. Wikipedia.

Kelly J.R.,University of Connecticut Health Center | Benetti P.,Sao Paulo State University | Rungruanganunt P.,University of Connecticut Health Center | Bona A.D.,University Of Passo Fundo
Dental Materials | Year: 2012

Objectives: This paper attempts to provide critical perspectives on common in vitro research methodologies, including shear bond testing, wear testing, and load-to-failure tests. Origins of interest in high-quality laboratory data is reviewed, in vitro data is categorized into property and simulation protocols, and two approaches are suggested for establishing clinical validity. It is hoped that these insights will encourage further progress toward development of in vitro tests that are validated against clinical performance and/or by producing clinically validated failure or damage mechanisms. Materials and methods: Published shear and tensile bond data (macro and micro) is examined in light of published finite element analyses (FEA). This data is subjected to a Weibull scaling analysis to ascertain whether scaling is consistent with failure from the bonded interface or not. Wear tests results are presented in light of the damage mechanism(s) operating. Quantitative wear data is re-examined as being dependent upon contact pressure. Load-to-failure test results are re-analyzed by calculating contact stresses at failure for 119 tests from 54 publications over more than 25 years. Results: FEA analyses and reported failure modes (adhesive, mixed, cohesive) are consistent with failure not involving interfacial "shear stresses" as calculated in published work. Weibull scaling clearly suggests failure involving external surfaces of specimens, not interfacial origins. Contact stresses (pressures) are clearly an important variable in wear testing and are not well-controlled in published work. Load-to-failure tests create damage not seen clinically due to excessively high contact stresses. Most contact stresses in the 119 tests examined were calculated to be between 1000 MPa and 5000 MPa, whereas clinical contact stresses at wear facets have been measured not to exceed 40 MPa. Conclusions: Our community can do a much better job of designing in vitro tests that more closely simulate clinical conditions, especially when contact is involved. Journals are encouraged to thoughtfully consider a ban on publishing papers using bond tests and load-to-failure methods that are seriously flawed and have no clinical relevance. © 2011 Academy of Dental Materials. Source

Geib L.T.C.,University Of Passo Fundo
Ciencia e Saude Coletiva | Year: 2012

Health is affected throughout the course of life by characteristics of social context, which produce inequalities in terms of exposure and vulnerability. These social determinants interfere with the well-being, functional independence and quality of life of the elderly, but are generally overlooked in interventions and policies. Therefore, the aim of this study was to systematize the knowledge of the social determinants of health in the elderly, using the Dahlgren and Whitehead model as a conceptual guide. The effects of demographic changes in the aging process and morbidity profile were approached at the structural level. The conditions of life and work with impact on current and future health and the role of social cohesion were studied at the intermediate level. Lastly, the behavior and lifestyles of major risk were examined at close quarters. It was detected that equity in health requires attention to social determinants during the course of life in order to minimize chronic diseases and deficiencies of the elderly, which reflect their social positions in early life. Source

Della Bona A.,University Of Passo Fundo | Corazza P.H.,Sao Paulo State University | Zhang Y.,New York University
Dental Materials | Year: 2014

Objectives To characterize the microstructure and determine some mechanical properties of a polymer-infiltrated ceramic-network (PICN) material (Vita Enamic, Vita Zahnfabrik) available for CAD-CAM systems. Methods Specimens were fabricated to perform quantitative and qualitative analyses of the material's microstructure and to determine the fracture toughness (KIc), density (ρ), Poisson's ratio (ν) and Young's modulus (E). KIc was determined using V-notched specimens and the short beam toughness method, where bar-shaped specimens were notched and 3-point loaded to fracture. ρ was calculated using Archimedes principle, and ν and E were measured using an ultrasonic thickness gauge with a combination of a pulse generator and an oscilloscope. Results Microstructural analyses showed a ceramic- and a polymer-based interpenetrating network. Mean and standard deviation values for the properties evaluated were: KIc = 1.09 ± 0.05 MPa m 1/2, ρ = 2.09 ± 0.01 g/cm3, ν = 0.23 ± 0.002 and E = 37.95 ± 0.34 GPa. Significance The PICN material showed mechanical properties between porcelains and resin-based composites, reflecting its microstructural components. © 2014 Academy of Dental Materials. Source

Benetti P.,Sao Paulo State University | Della Bona A.,University Of Passo Fundo | Kelly J.R.,University of Connecticut Health Center
Dental Materials | Year: 2010

Objectives: To test the hypotheses that shear bond strength (σ s) and contact angle (θ) are influenced by the thermal expansion/contraction behavior of bilayered all-ceramic systems. Methods: Glass-infiltrated ceramics (A - In-Ceram ALUMINA) and zirconia-reinforced alumina (Z - In- Ceram ZIRCONIA) were veneered with feldspathic ceramics (7 - VM7; 9 - VM9; 13 - VM13), yielding 6 experimental groups. Surface roughness (Ra) of A and Z core ceramic disks (12 mm diameter × 1.2 mm high) was measured to assure that values were similar. A cylinder of veneer (2 mm diameter × 2 mm high) was fired onto the center of all core disks, cooled under identical conditions and tested for σ s to failure (n = 20). For the θ evaluation (n = 10) similar specimens (veneer 1 mm high) were overfired to develop an equilibrium θ that was then measured from digital images (AutoCAD 2006). Published thermal expansion data were used. Results: The mean values of σ s (MPa) and θ (°) for the core-veneer ceramic groups were, respectively: A7 (19.4 ± 4.7; 49 ± 4.7); Z7 (23.4 ± 6.2; 56 ± 4.9); A9 (0.9 ± 1.6; 55 ± 5.8); Z9 (9.8 ± 5.7; 59.8 ± 2.9); A13 (0; 70 ± 6.0); Z13 (0; 67.2 ± 6.3). As the difference in coefficient of thermal expansion (coreveneer) increases, the θ value increases (r = 0.95) and the σ s value decreases (r = -0.92), p ≤ 0.01. Conclusion: The contact angle measurement and the shear bond strength test of core-veneer ceramics are influenced by the thermal expansion behavior of these all-ceramic systems. © 2010 Academy of Dental Materials. Source

There has been an increase of chronic diseases with the subsequent need for care and hospitalization, due to the acceleration of the elderly demographic growth. The objective of the present paper is to reflect on the care of nursing and the autonomy of the human being under the condition of elderly hospitalization. Nursing professionals, caring in the hospital ambient, can contribute significantly for the construction of the elderly autonomy and participation on the decision making about their need for attention or health care. The ethics redeeming, under a worthy aging perspective, permeates several discussions in the aging society and, specifically, among health professionals who act in hospital institutions. Source

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