Evaluation of Color Changes of Different Resin Cements in Feldspathic Ceramic Crowns After Accelerated Aging: An In Vitro Research

2021 ◽  
pp. 232020682110443
Author(s):  
Murat Eskitaşçıoğlu ◽  
Mehmet Şerif Akdeniz ◽  
Beyza Ünalan Değirmenci

Aims: To evaluate the color changes that occur after accelerated aging in feldspathic ceramic crowns cemented with three different dual-cured resin cements. Materials and Methods: For each of the A2-colored RelyX U200, G-CEM LinkForce, and Panavia V5 cement groups, 45 dies from A2-colored zirconia blocks and 45 crowns from CEREC blocks were prepared. Color measurements after 24 h of cementation (T1) and after cycles of aging of 1750 (T2), 3500 (T3), and 7000 (T4) in the thermal cycle device were made using SpectroShade Micro device. The coordinates of the color were used L*, a*, and b* as base and the color change was calculated with ∆ E00 in determining the color. One-way analysis of variance test was used to compare the times in terms of ∆ L*, ∆ a*, and ∆ b* values. Results: It was found that ∆ L* value decreased significantly in period of the T2, T3, and T4 times compared to T1 in all groups ( P < .05), whereas the change between period of T2, T3, and T4 times was not significant ( P > .05). The ∆ a* value increased significantly in the period of T3 and T4 times compared to T1 in the only G-CEM LinkForce group, whereas the ∆ b* value increased significantly in the period of T4 time compared to T1 in the only Panavia V5 group. The changes in ∆ E00 values, which were observed in all period of times, were found to be between 0.43 and 1.04, 0.43 and 1.43, and 0.40 and 0.97 in RelyX U200, G-CEM LinkForce, and Panavia V5 groups, respectively. Conclusion: After accelerated aging, it was found that the color of all cements became darker and the G-CEM LinkForce group turned red and the Panavia V5 group turned yellow. However, it was found that the color changes that occurred were within clinically acceptable visible levels.

Agriculture ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 252
Author(s):  
Jorge Luiz da Silva ◽  
Vasco Cadavez ◽  
José M. Lorenzo ◽  
Eduardo Eustáquio de Souza Figueiredo ◽  
Ursula Gonzales-Barron

This study aims to evaluate the effects of camu-camu powder (CCP), Amazonian berry fruit with documented bioactive properties, physicochemical meat parameters, and the growth kinetics parameters of S. enterica ser. Typhimurium, psychrotrophic bacteria (PSY), and lactic acid bacteria (LAB) in vacuum-packed ground beef. Batches of ground beef were mixed with 0.0%, 2.0%, 3.5%, and 5.0% CCP (w/w), vacuum-packed as 10 g portions, and stored at 5 °C for 16 days. Centesimal composition analyses (only on the initial day), pH, TBARS, and color were quantified on storage days 1, 7, and 15, while PSY and LAB were counted on days 0, 3, 6, 9, 13, and 16. Another experiment was conducted with the same camu-camu doses by inoculating S. enterica ser. Typhimurium microbial kinetic curves were modeled by the Huang growth and Weibull decay models. CCP decreased TBARS in beef from 0.477 to 0.189 mg MDA·kg−1. No significant differences in meat pH between treated and control samples were observed on day 15. CCP addition caused color changes, with color a* value decreases (from 14.45 to 13.44) and color b* value increases (from 17.41 to 21.25), while color L* was not affected. Higher CCP doses caused progressive LAB growth inhibition from 0.596 to 0.349 log CFU·day−1 at 2.0% and 5.0% CCP, respectively. Similarly, PSY growth rates in the treated group were lower (0.79–0.91 log CFU·day−1) compared to the control (1.21 log CFU·day−1). CCP addition at any of the investigated doses produced a steeper S. enterica ser. Typhimurium inactivation during the first cold storage day, represented by Weibull’s concavity α shape parameter, ranged from 0.37 to 0.51, in contrast to 1.24 for the control. At the end of the experiment, however, S. enterica ser. Typhimurium counts in beef containing CCP were not significantly different (p < 0.05) from the control. Although CCP affects bacterial kinetics, it does not protect ground beef against spoilage bacteria and Salmonella to the same degree it does against lipid peroxidation.


2016 ◽  
Vol 10 (1) ◽  
pp. 516-521 ◽  
Author(s):  
Vanessa Dias da Silva ◽  
Eduardo Martinelli S de Lima ◽  
Caroline Dias ◽  
Leandro Berni Osório

Proposition: The purpose of this study was to evaluate in vitro the color changes of esthetic orthodontic elastomeric ligatures of different shades when exposed to four food colorings commonly found in the diet of patients. Materials and Methods: The sample consisted of esthetic orthodontic elastomeric ligatures in the colors pearl, pearl blue, pearl white and colorless, which were immersed for 72 hours in five different solutions: distilled water (control group), coffee, tea, Coca-Cola ® and wine. The color changes of the esthetic orthodontic elastomeric ligatures were measured with the aid of a spectrophotometer, at T1 - as provided by the manufacturer; and T2 - after colorings process. Results: The results indicated that the esthetic orthodontic elastomeric ligatures of all initial hues are susceptible to pigmentation. Among the evaluated colors, all changed the finished look and the color of the samples tested. In ascending order, the color of the samples was as follows: distilled water, Coca-Cola®, black tea, wine and coffee. Conclusion: The substances that have a greater potential for pigmentation in esthetic orthodontic elastomeric ligatures were black tea, wine and coffee, respectively. All shades of esthetic orthodontic elastomeric ligatures are susceptible to color change.


2021 ◽  
Vol 869 (1) ◽  
pp. 012007
Author(s):  
A Yuslan ◽  
N Nasir ◽  
H Suhaimi ◽  
A Arshad ◽  
N W Rasdi

Abstract Copepods with a wide range of sizes, species, and nutritional compositions are preferred as live food for rearing of Betta splendens larvae. This research focuses on evaluating the efficiency of copepod enrichment diets in improving the coloration and feeding rate of B. splendens. Copepod were enriched with Chlorella sp. (T1), capsicum (T2), mixed vegetable (carrot + spinach), (T3), yeast (T4) and rice bran (T5) in 24 hours prior the feeding tests. As a result, proximate analysis of enriched-copepods showed that T1 (70.88±0.41) has highest protein content and T5 (22.01±0.59) has the highest lipid content. The specific growth rate and survival rate of B. splendens was highest in the treatment T1 (2.56±0.07%; 91.11±1.92%) and followed closely by T3 (2.49±0.51%; 85.55±8.39%). Feeding rate, T3 (70.08±3.88%) presented highest rate compared to other treatments. The different enrichment diets used were significantly impact the coloration test on body of L* value (P=0.001, P<0.05), T3 (66.11±3.60) appeared darker in color in contrast to others. As for a* value, the coloration was not impacted with the use of different enrichment on copepods (P=0.158, P>0.05) was detected for T1 (2.84±0.73) that gave a redder shade than other treatments did. T3 (2.40±0.30) exerted a more yellowish shade than the rest for b* value with a significant difference (P=0.015, P<0.05). The current study demonstrates that, rice bran, capsicum and mixed vegetable enrichment (carrot and spinach) have the potential to be an effective means of increasing B. splendens coloring and feeding rate. This potential diet can be further used as a substitution to artificial foods in producing sustainable culture of ornamental fish in the aquaculture industry.


Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1748
Author(s):  
Maria-Ioana Socaciu ◽  
Melinda Fogarasi ◽  
Cristina Anamaria Semeniuc ◽  
Sonia Ancuţa Socaci ◽  
Mihaela Ancuţa Rotar ◽  
...  

The effects of heat treatment and the addition of tarragon essential oil on physical and mechanical properties of films prepared with 5% whey protein isolate (WPI) and 5% glycerol were investigated in this study. Heat treatment of the film-forming solution caused increases in thickness, moisture content, swelling degree, water vapor permeability (WVP), b*-value, ΔE*-value, transmittance values in the 200–300-nm region, transparency, and puncture resistance of the film, but decreases in water solubility, L*-value, a*-value, transmittance values in the 350–800-nm region, and puncture deformation. When incorporated with tarragon essential oil, heat-treated films have the potential to be used as antimicrobial food packaging. The addition of tarragon essential oil in film-forming solution caused increases in moisture content, solubility in water, WVP, a*-value, b*-value, ΔE*-value, and transparency of the film; decreases in transmittance values in the range of 600–800 nm; and variations in swelling degree, L*-value, transmittance values in the range of 300–550 nm, puncture resistance, and puncture deformation. Nevertheless, different tendencies were noticed in UNT (untreated) and HT (heat-treated) films with regards to transparency, light transmittance, puncture resistance, and puncture deformation. Based on these findings, HT films show improved physical and mechanical properties and, therefore, are more suitable for food-packaging applications.


2016 ◽  
Vol 27 (1) ◽  
pp. 95-100 ◽  
Author(s):  
Francisca Daniele Jardilino Silami ◽  
Rafaella Tonani ◽  
Carla Cecilia Alandia-Román ◽  
Fernanda de Carvalho Panzeri Pires-de-Souza

Abstract The aim of this study was to evaluate the influence of accelerated aging (AAA) on the color stability of resin cements for bonding ceramic laminate veneers of different thicknesses. The occlusal surfaces of 80 healthy human molars were flattened. Ceramic laminate veneers (IPS e-max Ceram) of two thicknesses (0.5 and 1.0 mm) were bonded with three types of luting agents: light-cured, conventional dual and self-adhesive dual cement. Teeth without restorations and cement samples (0.5 mm) were used as control. After initial color evaluations, the samples were subjected to AAA for 580 h. After this, new color readouts were made, and the color stability (ΔE) and luminosity (ΔL) data were analyzed. The greatest color changes (p<0.05) occurred when 0.5 mm veneers were fixed with light-cured cement and the lowest when 1.0 mm veneers were fixed with conventional dual cement. There was no influence of the restoration thickness when the self-adhesive dual cement was used. When veneers were compared with the control groups, it was verified that the cement samples presented the greatest alterations (p<0.05) in comparison with both substrates and restored teeth. Therefore, it was concluded that the thickness of the restoration influences color and luminosity changes for conventional dual and light-cured cements. The changes in self-adhesive cement do not depend on restoration thickness.


Foods ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 139 ◽  
Author(s):  
Karen Alissa ◽  
Yu-Chi Hung ◽  
Chih Yao Hou ◽  
GiGi Chin Wen Lim ◽  
Jhih-Ying Ciou

Avocado (Persea Americana Mill.) generates byproducts, especially the avocado seeds. Hence, the aim of this study was to investigate the potential utilization of avocado seed as a very important, high phenolic content, climacteric fruit with unique characteristics and high nutritional properties. As such, theantioxidative test is conducted, then spray drying is used to produce avocado seed powder. The objective of this study was to develop an avocado seed powder using the spray drying technique by investigating the solution stability with different avocado seed extract concentrations, and to determine the physical properties of spray dried avocado powder that consists of powder yield, moisture, water activity, solubility, and color. The avocado seed extract was mixed with maltodextrin and water and homogenized for 10 min at 8000 rpm. The avocado seed solution was then spray dried with different inlet temperatures and feed flow rates. The spray dried avocado seed powder was analyzed for its yield, moisture content, water activity, solubility, and color. It was reported that the solution with the least avocado extract concentration (10 g) had the best stability in terms of presence of solute particles and color. The avocado seed powder obtained from this experiment had yield ranges from 24.46–35.47%, moisture content ranges from 7.18–7.96%, water activity ranges from 0.27–0.34, solubility ranges from 55.50–79.67 seconds, L* value ranges from 38.38–41.05, a* value ranges from 6.20–7.25, and b* value ranges from 13.33–15.17. In addition, increasing inlet temperature resulted in an increase in powder yield, solubility, a* value, and b*value, as well as a decrease in moisture, water activity, and L* value. Meanwhile, increasing the feed flow rate resulted in an increase in powder yield, moisture, water activity, and all L*, a*, b* values, as well as a decrease in solubility. In conclusion, spray drying technology is able to develop avocado seed powder.


2020 ◽  
Vol 32 (4) ◽  
pp. 1-4
Author(s):  
Abeer B Mahmood

Background: Aesthetic archwires are used to overcome the aesthetic problems of stainless steel wires but the color of the coating layer can be changed with time when exposed to oral environments. The aim of this study was to evaluate the degree of color change of different aesthetic archwires from different companies under different coloring solutions. Materials and Methods: One hundred fifty samples of coated archwires from three companies (Highland, G&H and Dany) were immersed in 5 solutions (artificial saliva, turmeric, tea, coffee and Miranda) to evaluate the degree of color changes after 7, 14 and 21 days using visible spectrophotometer. Data were collected and analyzed using one way ANOVA and post hoc Tukey’s tests. Results: Turmeric solution caused high color change than other solutions. Aesthetic archwires from Highland company showed the highest degree of color change than archwires from other companies. Conclusions: Turmeric solution produced more discoloration than other solutions and the effects of these solutions are related to different chemical compositions of those solutions.


2018 ◽  
Vol 149 ◽  
pp. 01088
Author(s):  
A. Hakam ◽  
N. El Imame ◽  
M. El kortbi ◽  
M. El Matar ◽  
M. Ziani ◽  
...  

The durability of exterior finishes on wood is not assured with the systems currently used. Thus, the objective of this study was to evaluate the color change of the finishes applied to wood, the most commercialized in Morocco, in order to find the wood-finishing couple that has the best durability in outdoor use. QUV accelerated aging tests were carried out during 2016 hours, according to the standard (NF 927-6 2006), on Scots pine (Pinus sylvestris) and Pedunculate oak (Quercus robur) coated with four finishes (two polyurethane finishes F1 and F2 and two acrylic finishes F3 and F4). Colorimetric measurements in color system CIELab: Gloss (L*), green-red (a*) and blue-yellow (b*) coordinates, color saturation (C*) and tone angle (H*) were performed using an X-Rite Model SP62 spectrophotometer before and at the end of the QUV accelerated aging treatment. The results showed that QUV aging caused a decrease in the L* value and a change in the surface color of all the finishing pairs studied. For wood / finishing couples with Quercus robur as a wooden support, the couple Quercus robur / F3 has the best resistance to color change, while for couples wood / finish with Pinus sylvestris as a wooden support, the couple Pinus sylvestris / F1 has the best resistance to color change.


2007 ◽  
Vol 18 (2) ◽  
pp. 119-123 ◽  
Author(s):  
Fernanda de Carvalho Panzeri Pires-de-Souza ◽  
Lucas da Fonseca Roberti Garcia ◽  
Hisham Mohamad Hamida ◽  
Luciana Assirati Casemiro

The purpose of this study was to evaluate, in vitro, the color stability of three composite resins of two different shades (A3 and C3) cured with either a quartz tungsten halogen (QTH) or a light emitting diode (LED) source. Forty specimens (20 x 2 mm) were prepared for each composite (Tetric Ceram®, Heliomolar® and Esthet-X®), being 20 for each shade. In each group, 10 specimens were light-cured using the QTH unit and 10 with the LED source. The shade of the materials was evaluated before and after submitting the specimens to artificial accelerated aging (4 h UV-B/4 h condensing vapor), using a reflection spectrophotometer. deltaE means were calculated and analyzed statistically by 2-way ANOVA and Tukey's test at 5% significance level. Both A3 and C3 shades of Esthet-X composite resin showed the lowest color change when cured with the QTH light, while Tetric C3 cured with the QTH light showed the highest color change.


2010 ◽  
Vol 35 (6) ◽  
pp. 605-609 ◽  
Author(s):  
M. Ghavam ◽  
M. Amani-Tehran ◽  
M. Saffarpour

Clinical Relevance While the studied cements behaved acceptably according to the color change index (ΔE), they functioned differently in regards to opacity, especially the self-cure ones.


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