scholarly journals Effect of storage time and composite thickness on Degree of Conversion of Bulk-fill and universal composites using FTIR method

2020 ◽  
Vol 23 (2) ◽  
Author(s):  
Farnaz Farahat ◽  
Abdolrahim Davari ◽  
Marzieh Fadakarfard

Objective: Degree of Conversion (DC) of Resin-Based composites (RBCs) is a concern and is affected by different factors. This study was conducted to evaluate the effect of different thicknesses and storage times on DC of bulk-fill and universal RBCs using the FTIR method. Material and methods: For each of dental composite (Tetric N- Ceram Bulk Fill and Tetric N Ceram), 28 samples were prepared (14 samples with 2 mm height and 14 samples with 4 mm height). One and seven days (1d and 7d) after storage in an incubator at 37 ˚C, DC was measured and recorded using a FTIR device. Data were analyzed using t-test and Three-Way ANOVA and Tukey Post-Hoc Test. P < 0.05 was considered statistically significant. Results: DC of Bulk-fill composite is greater than universal composite. DC at 2 mm thickness is more than 4 mm. Unlike universal composite, 7d DC of Bulk-fill composite is greater than 1d. Of course, none of these differences are statistically significant (P-value > 0.05). Conclusions: Considering the limitation of this study, since no difference was found between DC of 1d and 7d, 1d DC is sufficient for clinical procedures, such as polishing, and the laboratory tests.KEYWORDSBulk-fill composites; Degree of Conversion; FTIR.

2021 ◽  
Vol 9 (3) ◽  
pp. 151-157
Author(s):  
A. Apriantini ◽  
S. Adinata ◽  
Y. C. Endrawati

Duck meat is a perishable food that has a short shelf-life. Therefore, packaging is needed to be used tomaintain duck meat quality during storage, one of the ways to extend shelf-life of duck meat is usingpropolis extract as edible coating which is contained antioxidant substances which can be used to extendduring storage. The aim of this research was to analyze the effect of propolis extract as an edible coatingmaterial on duck meat to maintain the quality and extend shelf-life of duck meat at room temperature.The research was used a completely randomized design (CRD) factorial 4x3 with 3 replications,consisting of 4 propolis concentrations (0.0%, 0.5%, 1.0%, 1.5%) and 3 storage times (0 hours, 6 hoursand 24 hours). Duck meats coated with propolis extracts had a significant effect on the water content andantioxidant activity of duck meat (P < 0.05). The storage time had a significant effect on the pH valueand the cooking loss of duck meat (P <0.05). The addition of propolis extract and storage time had asignificant effect on the pH value, cooking loss and antioxidant activity of duck meat (P <0.05).


2019 ◽  
Vol 1 (2) ◽  
pp. 57-60
Author(s):  
Dharia Renate

Abstract--The objectives of this research were to know the effect of citric acid on papaya jam to its sensory propertiesduring storage and to determine the concentration of citric acid and storage time to the quality of papaya jam.  Material used was mature and ripe of fresh papaya, purchased from local market.  This research was designed as a Factorial Completely Randomized Designed.  The factors were the concentration of citric acids (0.3, 0.35, 0.4 percent w/w) and storage times (0, 1, 2, 3, 4 weeks).  The number of 18 trained panelists evaluated the color, texture, spreadibility and flavor.  Data was analyzed using analysis of variance.  The significantly different treatment was further analyzed by using  Multiple Comparison and TukeyTest.  The results indicated that the concentration of citric acids and storage time had significant effects on the quality of papaya jam.  Research concluded that the concentration of citric acids of 0.4 percent and storage time of 2 weeks were found to yield the best quality in papaya jam.  The papaya jam was good in light yellow color, soft  texture, good spreadibility, liked flavor, hence the consumeracceptance like this papaya jam.


2016 ◽  
Vol 17 (3) ◽  
pp. 217-223 ◽  
Author(s):  
Maan M AlShaafi

ABSTRACT Objective Dental materials are often made at room temperature, whereas clinically they are made in the mouth. This study evaluated the effects of temperature on the degree of conversion (DC) and Knoop microhardness (KHN). Materials and methods Two types of resin-based composites (RBCs) were light-cured using a light-emitting diode (LED) lightcuring unit. The resin specimens were centered on an Attenuated Total Reflectance Fourier transform infrared (FT-IR) plate heated to 23°C or 33°C. The DC of the resin was calculated after 120 seconds, the specimens were removed, and the KHN was tested at the bottom of the specimens both immediately, after 24 hours, and after 7 days storage in distilled water in complete darkness at 37°C. The effects of different temperatures on the DC and KHN with their storage time were compared by analysis of variance and Fisher's protected least significant difference post hoc multiple comparison tests (p < 0.05). Results Increasing the temperature had a significant and positive effect on the DC and KHN for immediate values of the RBCs. Greater conversion and hardness occurred when the curing temperature was increased from 23°C to 33°C. The KHN increased significantly after 24 hours of storage. There was a linear relationship between DC and KHN (R2 = 0.86) within the range of DC and KHN studied. Conclusion The physical properties of dental materials can be expected to be better when made in the mouth than when they are made in a laboratory at room temperature. How to cite this article AlShaafi MM. Effects of Different Temperatures and Storage Time on the Degree of Conversion and Microhardness of Resin-based Composites. J Contemp Dent Pract 2016;17(3):217-223.


2017 ◽  
Vol 52 (2) ◽  
pp. 129-132 ◽  
Author(s):  
Wilian Vinicius Bortoletto ◽  
Willian Rodrigues Macedo ◽  
Thalyta Coelho de Oliveira ◽  
Daniela Silva Souza

Abstract: The objective of this work was to investigate the potential physiological damage of the treatment of '97Y07RR' soybean seeds with different pesticides at different storage times, in order to define the optimal period of sowing. The germination rate, the germination speed index, and shoot fresh matter were evaluated. Thiamethoxam did not cause losses in seed vigor with increasing storage time; however, the other agrochemicals caused significant losses. Seed treatment should be performed up to 90 days before sowing.


2013 ◽  
Vol 14 (1) ◽  
pp. 76-79 ◽  
Author(s):  
Mateus Rodrigues Tonetto ◽  
Marcelo Ferrarezi de Andrade ◽  
Shelon Cristina Souza Pinto ◽  
Alvaro Henrique Borges ◽  
Matheus Coelho Bandéca ◽  
...  

ABSTRACT Aims and objectives The behavior of polymer-matrix composite is dependent on the degree of conversion. The aim of this study was to evaluate the degree of conversion of two resin cements following storage at 37°C immediately, 24 and 48 hours, and 7 days after light-curing by FTIR analysis. Materials and methods The specimens were made in a metallic mold and cured with blue LED with power density of 500 mW/ cm2 for 30 seconds. The specimens were pulverized, pressed with KBr and analyzed with FTIR following storage times. Statistical analysis used ANOVA (two-way) and Tukey's post hoc. Results To the polymer-matrix composites between 24 and 48 hours does not show a significant increase (p > 0.05), however, the highest values were found after 7 days. Conclusion The polymer-matrix composites used in this study showed similarity on the degree of conversion and increased of according to the time of storage. How to cite this article Tonetto MR, Pinto SCS, de Nara Souza Rastelli A, Borges AH, Saad JRC, Pedro FLM, de Andrade MF, Bandéca MC. Degree of Conversion of Polymer-matrix Composite assessed by FTIR Analysis. J Contemp Dent Pract 2013;14(1):76-79.


2021 ◽  
Vol 45 (1) ◽  
Author(s):  
Ragia M. Taher ◽  
Lamiaa M. Moharam ◽  
Amin E. Amin ◽  
Mohamed H. Zaazou ◽  
Farid S. El-Askary ◽  
...  

Abstract Background This study was conducted to evaluate the effect of radiation exposure and storage time on the degree of conversion (DC%) and flexural strength (FS) of three different resin composites. In total, 90 disk-shaped, and 360 rod-shaped composite specimens were prepared to evaluate the DC% and FS, respectively. Specimens were divided into 18 groups (DC%: n = 5 and FS: n = 20) according to the three experimental factors of the study: 1—Radiation (no-exposure and exposure), 2—Resin composite material (Herculite XRV Ultra, Z250 XT and Grandio), and 3—Storage time (24 h in distilled water, 3-m and 6-m in 70% ethanol). Fourier transform infrared spectrometer (FTIR) was used to determine the DC%. For FS, the specimens were subjected to a three-point bending test at 1 mm/min crosshead speed. Data were analyzed using three-way ANOVA/Tukey HSD test. Significant level was set at P = 0.05. Results For DC%, there was no significant difference between no-radiation exposure and radiation exposure (P > 0.05). Herculite XRV Ultra revealed the highest statistically significant DC% (P < 0.05). The 24-h storage time revealed the least significant DC% (P < 0.05). For FS, radiation exposure showed a statistically significant higher value compared to no-radiation exposure (P < 0.05). Herculite XRV Ultra showed the least FS value (P < 0.05). The 24-h storage time showed the highest significant value (P < 0.05). Conclusions Radiation exposure has no significant impact on the DC% of the different resin composites, but it has a significant positive effect on the FS. Storage time had a significant effect on both DC% and FS.


2014 ◽  
Vol 15 (4) ◽  
pp. 409-413 ◽  
Author(s):  
Rafael Carlos Nepomuceno ◽  
Pedro Henrique Watanabe ◽  
Ednardo Rodrigues Freitas ◽  
Carlos Eduardo Braga Cruz ◽  
Maria Simone Mendes Peixoto ◽  
...  

A trial was conducted to evaluate quality of quail eggs from two companies (A and B) at two storage times (5 and 15 days after packing). A total of 480 eggs were kept at room temperature and distributed in a completely randomized design in 2x2factorial arrangement (companies and storage time). The results indicated that trays from company B presented higher weight, as well as mean egg weight. However, the eggs in trays from company A showed greater uniformity. Evaluating the external quality, we found that above 90% of eggshell were considered with total integrity, and no difference for this characteristic between companies was found. The eggs from company A presented lower average weight in comparison to those from company B, regarding storage time. No differences were observed between eggs from companies A and B for Haugh unit value. Storage time of 15 days after packing promoted reduction in Haugh unit value in comparison to those stored for 5 days. Quail eggs from company A presented lower variation in weight, although heavier eggs are produced by company B. Internal quality of quail eggs from both companies was similar. Storage time affected eggs quality.


2020 ◽  
Vol 9 (2) ◽  
pp. 192-198
Author(s):  
Indah Nuraini Masjkur ◽  
Evy Arfianti ◽  
Ahmad Yudianto ◽  
Abdul Hadi Furqoni ◽  
Qurrota A’yun

The samples used for forensic DNA analysis in living individuals are usually blood and buccal swabs, however, blood collection requires an invasive method that can cause discomfort, thus a buccal swab can be a good choice for individuals examined, especially children. This study aimed to determine the effect of temperature and storage time of buccal swabs on the quantity of DNA as material for DNA examination in the forensic field. This study was a laboratory experiment to determine the effect after treatment. Buccal swab samples were 48 and divided into 2 temperature groups, namely room temperature (RT) and 4℃. The division of the temperature groups was also observed with time differences, namely 1, 3, 5, 7 days. EDNA extraction used the DNAzol method and DNA quantification used a Spectrophotometer. The PCR process was carried out with STR primers FGA and D13S317 loci. The visualization stage used acrylamide gel and silver staining. The results of this study prove that there is an effect of temperature and storage time of buccal swab samples. The longer the treatment time, the lower the DNA level. With statistical analysis, it is obtained p-value of <0.005, it can be concluded that there are significant differences in DNA levels at the temperature and storage time treatments of the buccal swab sample. The results of DNA visualization at the FGA and D13S317 loci using the STR PCR method in this study can still be detected and can be used as a reference for examination in forensic cases.  


2018 ◽  
Vol 9 (1) ◽  
pp. 112
Author(s):  
Luzia Caroline Ramos dos Reis ◽  
Ester Alice Ferreira ◽  
Heloisa Helena Siqueira Elias ◽  
Eduardo Valerio Vilas Boas ◽  
Alessandro De Oliveira Rios

This study aimed to evaluate the effect of refrigeration and the storage time of fresh and minimally processed tangerine 'Dekopon' seeking to increase its useful life for marketing. In experiment 1, the harvested fruit were stored in temperatures of 4, 8 and 12 °C and analyzed in 0, 5 and 10 days. In experiment 2, the fruit were minimally processed and storage at temperatures of 4, 8 and 12 °C and analyzed 0, 3, 6, 9 and 12 days. The analysis of the evaluated data were weight loss, pH, total soluble solids (TSS), titratable acidity (TA), ratio TSS:TA, Vitamin C and color parameters. The results for experiment 1 showed that in general, day 0 presented higher values of physicochemical parameters and day 5 at 8 °C presented higher concentration of vitamin C. For experiment 2, in the minimally processed fruit, day 3 demonstrated more retention of physicochemical parameters, except for mass loss and day 12 at 4 °C resulted in a higher content of vitamin C.


2018 ◽  
Vol 47 (1) ◽  
pp. 51-56
Author(s):  
Natália Pereira de OLIVEIRA ◽  
Renata Pilli JÓIAS ◽  
Rodnei Dennis ROSSONI ◽  
Renato Morales JÓIAS

Abstract Introduction The most used material for the preparation of the baseplates is the acrylic resin, but it can present distortions. Objective To evaluate preparation technique, region and storage time that presents less maladaptation of the base when made with self-cured acrylic resin. Material and method Models were created in gypsum type III simulating edentulous maxilla, as divided into 3 groups (n = 10): GC (control group) thermopolymerizable acrylic resin; G1 - manual adaptation technique and G2 - drip technique. For the measurements, silicone by condensation of light consistency that was interposed between base and model was used. With a hydraulic press, 50 kg pressure was applied leading the base of the model. The obtained mold was measured in the palate, canine and molar regions with a digital caliper at the following times: immediately after the base polymerization, at 24, 48, 72, 96 hours and one week. The results were submitted to statistical analysis. Result G1 presented maladaptation of 0.43 mm ± 0.10, while G2 obtained 0.39 mm ± 0.11. The lowest maladaptation occurred in the CG. The palate region presented greater maladaptation (0.52 ± 0.07) and the canine region, the lowest (CD = 0.27 mm ± 0.07 and CE = 0.27 ± 0.09); There was no statistically significant difference for storage times. Conclusion G2 presented lower values than G1, with no statistically significant difference. The palate region presented greater maladaptation, followed by molars and canines. The bases continued to maladaptation the model after the immediate polymerization, with no statistically significant difference.


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