Percorrer por autor "Ramalho, A."
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- Effect of bleaching teeth with hydrogen peroxide on the morphology, hydrophilicity, and mechanical and tribological properties of the enamelPublication . Rodrigues, F. T.; Serro, A. P.; Polido, M.; Ramalho, A.; Figueiredo-Pina, C. G.The tooth whitening process is intended to restore the original color of teeth. It consists of the application of oxidizing agents, including hydrogen peroxide. Although these products considerably improve the color of teeth, their effects on other properties of enamel are not fully understood. This work aimed to study the effects of hydrogen peroxide concentration on hydrophilicity, roughness, morphology, and mechanical and tribological properties of human tooth enamel. Human teeth were subjected to bleaching sessions with 6%, 15%, and 35% hydrogen peroxide to achieve a similar level of whitening. The enamel roughness and morphology were characterized by atomic force microscopy and scanning electron microscopy. Vickers microindentation hardness data were obtained. The hydrophilicity was determined using the captive bubble method. Reciprocating, ball-on-flat friction, and wear tests were conducted in artificial saliva using zirconia as the ball and polished enamel as the flat specimens. Although all three test solutions improved tooth color, they also changed the properties of the enamel. Morphological and roughness changes were observed, and there was a decrease in hardness and wear resistance. The wettability was nearly unaffected. It was found that the 15% hydrogen peroxide solution damaged the enamel the least. It was concluded that there is an ideal concentration of hydrogen peroxide for whitening treatments.
- Influence of an Atypical Academic Year on the Physical Activity Levels of 1st Year Students of PhysiotherapyPublication . Teles, C.; Ramalho, A.; Gameiro, J.; Bernardino, J.; Marçal, T.; Silva, C. R.; Alves Lopes, AntónioBackground: Portugal is one of the European Union countries with the lowest rate of Physical Activity (PA), with only 40% of the population being active. During the university period, there is an increased autonomy and decision-making among students, and changes in life habits, usually associated with a decrease in PA practice. In percentage terms, 30% of university students are considered physically inactive. There are few studies on PA levels in higher education students, namely in the Physiotherapy degree, and even less that relate this topic to the imposed containment measures, due to the COVID-19 pandemic. Purpose: Description and comparison of the PA levels of students enrolled in the 1st year of a Physiotherapy degree, in a Health School, in the academic year 2019/2020. Understand if there are differences in the practice of PA, at different times of the school year, one of which is the quarantine period. Methods: Data were collected using the “International Physical Activity Questionnaire” (IPAQ), in its short version. It was shared in online format in 3 moments (academic period without evaluations, exam period and online classes /social isolation), being a longitudinal study. Results: Physiotherapy students seem to be active regarding the parameter of PA frequency. With online classes, there was an increase in the level of PA in 20% of students compared to the school period without assessments, with 14.3% being raised to a high level of PA. The high percentage of students (42.9%) who maintained a high PA level should be highlighted. There was a significant difference from the 1st to the 2nd moment, at the IPAQ level, with a decrease in PA (p = 0.03) with the exam period. Conclusion(s): In the exam period, although the workload on the schedule is shorter, there seems to have been a decrease in PA levels. In a situation of confinement, aspects are presumed to have been removed, which in a normal situation would compromise the practice of PA, leading to better results in some of the variables under study. Thus, the quarantine period does not appear to have had a negative impact on PA. The objective of this study was achieved, establishing a starting point for the assessment of PA levels, in university students, in the period of COVID 19. We suggest conducting studies with larger samples and using more objective assessment instruments. As the sample is composed of future health professionals, it is important that they be the first to adopt an active lifestyle, thus promoting it.