Examinando por Materia "Acrylic resin"

Mostrando 1 - 4 de 4

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Chromatic stability against coffee of an acrylic and bis-acrylic resin used for the manufacture of provisional crowns in fixed prosthesis. In vitro study. Lima, Peru 2022
(Universidad Privada Norbert Wiener, 2023-11-30) Barrionuevo Salgado, Katya Eleuteria; Guevara Sotomayor, Juan César
Objective: To determine the color stability of an acrylic and a bis-acrylic resin when exposed to coffee, used for the fabrication of provisional crowns in fixed prosthodontics. Methodology: An experimental study with a quantitative approach and applied type, using a hypothetical deductive methodology. An acrylic resin (Alike) and a bis-acrylic resin (Visalys Temp) were used to create 10 mm diameter by 2 mm thick discs. Once the discs were prepared, their initial color was checked using the Vita classical shade guide, and the information was recorded in the data collection form. A total of 11 discs of each type were made and immersed in two glass containers containing a coffee solution for a period of 1 week. The discs were only removed from the container to assess color stability at 1 hour, 24 hours, and one week after exposure. Results: The acrylic resin Alike showed a color variation of 0.45 after 1 hour of exposure to coffee, 3.82 after 24 hours, and 4.27 after 1 week. Meanwhile, the bis-acrylic resin Visalys Temp showed a color variation of 8.64 after 1 hour, 12.82 after 24 hours, and 13.91 after 1 week of exposure. Conclusion: Both resins showed color variation, with the bis-acrylic resin showing more noticeable changes in the same period of time
Acceso abierto
Degree of pigmentation of resin and composite resin teeth acrylic in vitro tests and the influence of carbonated drinks Lima-2021
(Universidad Privada Norbert Wiener, 2023-04-13) Loayza Cáceres, Yessenia Leonor; Marroquín García, Lorenzo Enrique
The degree of pigmentation of teeth with composite resin and acrylic resin was determined in in vitro tests influenced by carbonated beverages. The total sample consisted of 32 teeth, divided into two groups of 16 elements, made of composite resins and acrylic resins. The study was longitudinal and experimental, comparing the degree of pigmentation due to exposure to carbonated beverages at 30 and 60 minutes. Statistical analysis was performed using Pearson's statistical test. The variations showed an initial average color value of composite resin and Coca-Cola of 92.3375, for Fanta® 92.4000; acrylic resin with Fanta® 79.9875, Coca-Cola® 81.6000. After 30 minutes of exposure, composite resin with Coca-Cola® had a value of 87.8125, Fanta® 91.5125; acrylic resin with Fanta® 85.5750, acrylic resin with Coca-Cola® 91.0125. After 60 minutes, composite resin with Coca-Cola® had a mean value of 80.4750, with Fanta® 81.8500, acrylic resin with Fanta® 81.4875, acrylic resin with Coca-Cola® 82.6000. Conclusion: Carbonated beverages influence the degree of pigmentation of teeth with composite and acrylic resins.
Acceso abierto
Evaluation of the effect of cigarette smokeon the color in acrylic resin teeth of the Ivostar and Olympic brands: in-vitro study, Lima 2022.
(Universidad Privada Norbert Wiener, 2023-12-11) Vargas Rodríguez, Elena Cristina; Llerena Meza De Pastor, Verónica
The objective of the study was to determine whether cigarette smoke affects the color of acrylic resin teeth from the Ivostar and Olympic brands: an in vitro study. An in vitro, comparative, prospective, and longitudinal study was conducted with 40 acrylic resin teeth from the Ivostar and Olympic brands, each consisting of n = 20 acrylic resin teeth. The initial luminosity, chroma, and hue of the acrylic resin teeth were evaluated using a Spectrophotometer (Vita Easyshade V). The teeth were then exposed to a cigarette smoke simulator, and the color was evaluated after 15 and 30 days. Numerical values were collected using a data collection sheet. The data were analyzed using SPSS version 22.0. The results showed that the mean luminosity for Ivostar brand teeth exposed to cigarette smoke initially was 85.29 nm, at 15 days it decreased to 83.3 nm, and at 30 days it further decreased to 81.57 nm. The chroma values initially were 24.57 nm, at 15 days 25.72 nm, and at 30 days 26.90 nm. The initial hue values were 88.38 nm, at 15 days 89.96 nm, and at 30 days 91.91 nm. The Olympic brand showed an initial luminosity of 83.84 nm, with 79.53 nm at 15 days and 76.6 nm at 30 days. The chroma mean values started at 19.28 nm, at 15 days it reached 21.28 nm, and at 30 days it was 23.95 nm. The hue values for Olympic brand teeth started at 90.24 nm, at 15 days reached 92.53 nm, and at 30 days it was 94.54 nm. In conclusion, Ivostar showed better initial luminosity values, which progressively decreased with exposure to cigarette smoke. As for chroma, Ivostar showed better initial values and an increase over time. However, Olympic exhibited changes in hue over the course of the study, with increases at 15 and 30 days.
Acceso abierto
Mechanical surface microhardness of a thermo-curing acrylic resin associated with zirconium nanoparticles
(Universidad Privada Norbert Wiener, 2023-10-23) Apomayta Hinojosa, Michael; Vilchez Bellido, Dina
Objective: To determine the mechanical surface microhardness of a thermocured acrylic resin associated with zirconium nanoparticles, Lima - Peru. Materials and Methods: This research is an in-vitro experimental study, cross-sectional, and prospective. The sample consisted of 03 study groups, which were further divided into 06 subgroups, measured at 24 and 48 hours, and met the inclusion and exclusion criteria. The equipment used for the measurement of mechanical surface microhardness was the Vickers microhardness tester, and the data was recorded on a data collection form. Statistical analysis was conducted using the Shapiro-Wilk test, and for bivariate analysis of the mechanical surface microhardness values between the materials, the ANOVA-Tukey test (24 hours) and Kruskal-Wallis with post hoc Dwass-Steel-Critchlow-Fligner pairwise comparisons (48 hours) were used. Comparisons between the 24-hour and 48-hour results were made using the Mann-Whitney U test and Student's T-test. All tests were analyzed with a 95% confidence level. Results: The acrylic resin associated with 3% zirconium nanoparticles showed the highest bond strength value (p < 0.05), followed by the acrylic resin.