• Journal of dental hygiene science
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• v.17 no.6
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• pp.481-486
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• 2017

The study aimed to compare the whitening efficacy of a strip and gel containing 2.9% hydrogen peroxide, using a tooth whitening light activator. The whitening effect was compared through in vitro and in vivo studies. In the in vitro study, we used stained hydroxyapatite (HAP) specimens as artificial teeth. HAP specimens were made using HAP powder and polyvinyl alcohol solution, and stained by modified Stookey's method. A whitening gel and whitening strip were applied to the respective specimens for 20 minutes, with a light activator. The color changes were measured using a colorimeter. In the in vivo study, one group (test 1) used the gel with a light activator and the other group (test 2) used a strip with the same activator for 15 minutes a day, for four consecutive days. An organoleptic evaluation using a Vita shade guide and instrumental evaluation using a Shade eye-NCC (Shofu Co., Japan) were performed. The color change values (${\Delta}E^*$) in the in vitro study revealed the strip with the light activator to be more effective than the gel with the same activator (p<0.001). In the in vivo study, even though there was no significant difference between the groups with respect to the ${\Delta}E^*$, using either the Shade eye-NCC or the Vita shade guide, the change in yellowness (${\Delta}b^*$) was statistically significant (p=0.024). In conclusion, test 2 group that used 2.9% hydrogen peroxide strip with a light activator, showed a tendency towards increased whitening than test 1 group that used the gel with the same activator; however further studies are needed to validate the above finding.

• Food Science and Preservation
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• v.20 no.3
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• pp.372-378
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• 2013

The objective of this study was to evaluate the quality characteristics of mungbean starch gels that were prepared with different concentrations (0, 0.5, 1.0 and 1.5%) of peach seed powders (PSP), which exhibit antioxidant characteristics. Mungbean starch gel samples were prepared and subjected to quality characteristics such as moisture content, general components, color, texture profile analysis, total polyphenol contents, DPPH radical scavenging activity, and sensory qualities. The L-value and the a-value for color decreased significantly, whereas the b-value increased significantly as the PSP concentration increased (p<0.05). In the texture profile analysis, the mungbean starch gel with 1.5% PSP showed significantly lower degrees of hardness, cohesiveness, springiness, gumminess and brittleness (p<0.05). The total polyphenol content was highest in the 1.5% PSP to which mungbean starch gel was added, which also showed a higher than 70% DPPH radical scavenging activity level in a dose-dependent manner (p<0.05). In the sensory test of the mungbean starch gel, its sensory scores for flavor and taste were highest in the 0.5% PSP to which mungbean starch gel was added.

• Journal of Pharmaceutical Investigation
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• v.28 no.2
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• pp.87-92
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• 1998

Kojic acid (KA) is an antimelanogenic agent which has been widely used in cosmetics to whiten the skin color. However, it has the drawbacks of the skin irritancy and the instability against the pH, temperature, and light. In order to overcome these problems, various topical gels and multiple emulsion creams which can control the release of active ingredient, KA, were formulated employing cream bases of mineral oil with caprylic capric triglyceride and hydrophilic polymers such as chitosan, carbopol. and pluronics. Using Franz diffusion cells mounted with a synthetic cellulose membrane (MWCO 12,000), drug release characteristics of the formulations were evaluated by the HPLC assay of KA concentration in the receptor compartment of pH 7.4 phosphate buffered saline solution. Drug release from chitosan-based gels (ChitoGel) obeyed to the first order kinetics with a rapid release especially in the initial period. However, pluronic-based gels (PluGel) and carbopol-based gels (CarboGel) revealed controlled release of drug to some extent, followed by the square root-time kinetics. Moreover, the release of KA was further controlled with the W/O/W multiple emulsion creams (MultiCream), showing the apparent zero order release kinetics by virtue of dynamic ratecontrolling membrane of the oil layer. The flux $(J,\;{\mu}g/cm^2/hr)$ of ChitoGel. CarboGel. PluGel. and MultiCream in the initial period of 6hr were 73.30, 28.67. 24.04 and 7.72, respectively. On the other hand, the skin irritancy score of ChitoGel and MultiCream were observed as 2.5 and 2.3 respectively, in the rabbit skin irritation test. Although there were insignificant differences at p<0.05 between those formulations, it was possible to conclude that the W/O/W multiple emulsion creams containing KA might be a good candidate for an antimelanogenic drug delivery system due to the controlled release of acidic drug molecules.

• Korean journal of food and cookery science
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• v.15 no.5
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• pp.539-544
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• 1999

This study attempted to determine the effect of storage temperature(5$^{\circ}C$ and 25$^{\circ}C$) and time(1, 24, 48 and 72 hours) on the sensory and textural properties of mungbean starch gels. The color value, syneresis, texture and sensory properties of mungbean starch gels were measured. As the storage time increased, the lightness(L) and whiteness(W) values of mungbean starch gel increased. This trend was more apparent at the storage temperature of 5$^{\circ}C$. The syneresis of gels also increased as the storage time increased and the storage temperature was lower. As the storage time increased, the hardness of the gel increased whereas the adhesiveness and cohesiveness of the gel decreased. These results showed that mungbean starch gel lost its typical viscoelasticity during storage. This trend was also more apparent at the storage temperature of 5$^{\circ}C$. Sensory characteristics of the gel were well correlated with the mechanical characteristics. Overall quality of the gel decreased markedly at the 2nd day storage at 5$^{\circ}C$ and at the 3rd day storage at 25$^{\circ}C$.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.6
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• pp.829-834
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• 2015

A simple and sensitive hydrogel-based detecting gel has been presented for the qualitative determination of cyanogen chloride(CK) using Konig reaction. To optimize Konig reaction conditions, the effects of pyridine and barbituric acid concentration were investigated. Under the optimized conditions, CK gas concentration was directly related with absorbance change at 567 nm. Based on aqueous solution test results, we finally prepared CK detecting hydrogel by absorbing pyridine and barbituric acid solution. Color change of the prepared CK detecting hydrogel was clearly observed when the detecting gel was exposed to 10 ppm CK gas.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.4
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• pp.492-499
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• 2000

This study was investigated to compare the staining resistance of soft denture liners. Specimens were made of Coe-soft, Coe-comfort, Soft-liner, Visco-gel, and were stored in 1% methyleneblue solution for 24 hours. The amounts of color change before and after treatment with mono-poly and thermocycling were measured by colorimeter(TC-6FX, Tokyo Denshoku Co. Ltd, Japan) for evaluation of staining resistance. The following conclusions were drawn from this study. 1. The staining resistance of Visco-gel was increased, but there was no changes of staining resistance in Coe-soft, Coe-comfort, and Soft-liner after treatment with monopoly. 2. The staining resistance of the Coe-comfort was the least in all soft denture liners. 3. The staining resistance of Visco-gel and Soft-liner were decreased after thermocycling.

• Journal of the Korean Society of Food Culture
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• v.24 no.2
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• pp.212-218
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• 2009

This study was carried out to determine the quality characteristics of Jeju mandarin orange jellies containing sugar (control) and sugar derivative sweeteners (erythritol, isomaltooligosaccharide, sorbitol, and xylitol) to be consumed by the elderly. The gelling agents were carrageenan and gellan gum at the concentration of 0.27%, respectively. The average age of the subjects for the acceptance test was 78. The lightness (L), redness (a), and yellowness (b) values of the carrageenan gel were higher than those of the gellan gum gel using the same sugars. The L, a, and b values of the carrageenan gel made with sugar derivative sweeteners were higher than those of the respective gel made with sugar. Whereas there were almost no differences between the color values of the gellan gum gels made with sugar and sugar derivative sweeteners, respectively. The gelling and melting temperatures of the carrageenan gel with erythritol were highest and those of the respective gel with xylitol were lowest among the sugar derivative sweeteners. The gelling and melting temperatures of the gellan gum gels with erythritol and isomaltooligosaccharide, respectively, were lower, and those of the respective gel made with xylitol were higher compared to that with sugar. There was no break down in the gellan gum gel. The break down rate of the carrageenan gel made with isomaltooligosaccharide was highest and that of the respective gel with xylitol was lowest among the sugar derivative sweeteners. The hardness, adhesiveness, springiness, and chewiness of the gellan gum gel were greater compared to the carrageenan gel. The adhesiveness levels of the carrageenan gels made with sugar derivative sweeteners were lower, and their springiness was higher than the respective gel with sugar. All the TPA characteristics of the gellan gum gels made with erythritol and xylitol, respectively, were higher than the respective gel with sugar. The rupture properties of the gels were the same as their TPA characteristics. The sensory acceptance of the carrageenan and gellan gum gels made with sugar were highest among all the sweeteners. There were no significant differences in the sensory acceptance scores of the carrageenan gels made with xylitol, erythritol, and sugar, respectively, and there were also no significant differences in the sensory acceptance scores of the gellan gum gels made with xylitol, sorbitol, and sugar, respectively. Xylitol was preferred in both the carrageenan and gellan gum gels. Thus, xylitol appears to be an appropriate alternative sweetener to sugar in Jeju mandarin orange jelly for consumption by the elderly, with regard to the acceptability and stability of the gel.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.04a
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• pp.206-206
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• 2005

• Journal of the East Asian Society of Dietary Life
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• v.18 no.1
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• pp.72-79
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• 2008

This study investigated the changes in textural characteristics that occurred by adding maltose syrup, dextrin, and sucrose to whole egg gels, by assessing coagulation after cooling. It also examined the optimal NaCl and sucrose concentrations for whole egg gels sensory evaluations, and then studied how the addition of sucrose effected gel formation and textural characteristics under optimal NaCl concentration. The additions of maltose syrup, dextrin, and sucrose, presented some color changes. The greater the addition of maltose syrup or dextrin, the lower the L, a, and b values of the whole egg gel and whole egg liquid, and ultimately the color turned dark bluish green. With increasing additions of sucrose, maltose syrup, and dextrin, the viscosity of the whole egg liquid increased slightly. In terms of the mechanical texture characteristic of the gel, the texture was most elastic with the 0.8% addition of sucrose, and hardness decreased by increasing the ratio of added sucrose. Increasing amounts of maltose syrup resulted in less hardness and SF. And for dextrin, the SF increased up to 2.5 and then decreased, and hardness decreased with increasing amounts of dextrin. Based on sensory evaluations, the 0.8% addition of NaCl was significantly preferred(p<0.05), in terms of salty taste. The overall preference scores indicated that the whole egg gel made with 0.3% sucrose and the optimal NaCl concentration(0.8%) was most preferred, and each sample was significant(p<0.05). Under the optimal 0.8% NaCl concentration increasing the sucrose concentration resulted in a darker egg gel color, in terms the L value. SF, NF, and hardness, which are mechanical texture parameters, were when 0.8% sucrose and the optimal NaCl concentration of 0.8% were added to whole egg liquid, in preparing the whole egg gel.

• Archives of Plastic Surgery
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• v.33 no.6
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• pp.700-705
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• 2006

Purpose: For hypertrophic scars and keloids no universally effective treatment modality exists. Surgical revision, intralesional steroid injection, silicone gel sheeting, pressure, laser, and others have been used with variable success, but many treatments are associated with high recurrence rates. Although optimal treatment remains undefined, successful treatment can be obtained through a combined therapeutic approach. Methods: We used three therapeutic modalities in combination, which are intralesional injection of triamcinolone acetonide, silicone gel sheeting, and 585 nm flashlamp-pumped pulsed dye laser. Fifty-eight cases of hypertrophic or keloid scar were treated by combined therapeutic regimen for mean period of 18 months. The changes of thickness, color, and pliability of scars were evaluated with clinical photographs by grading scale. Results: As summing the grades and categorizing the result into three group, we obtained 28% good, 67% fair, and 5% poor results. There was a desirable improvement of scars with insignificant adverse effects. Conclusion: Combination of intralesional steroid injection, silicone gel sheeting, and pulsed dye laser can lead to successful treatment of hypertrophic scar and keloid.