• Journal of Digital Convergence
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• v.17 no.1
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• pp.357-364
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• 2019

This study comparatively analyzed hair damage by hair bleach particles and identified three different bleach particle sizes using a scanning electron microscope (SEM). The powdered bleaching agents made of ammonium persulfate (APS) and potassium persulfate had particle sizes of $131{\mu}m$, $72{\mu}m$ and $48.8{\mu}m$. According to a hair damage test, cuticle lift-up or peeling hardly occurred when small bleach particles were used. In terms of hair color, the hair bleached with larger bleach particles was the darkest, while the hair bleached with small bleach particles was the brightest. The results found that for bleaching agents that are more effective in easing hair damage, those with little particles should be used. In addition, it appears that the selection of particles depending on the degree of hair bleaching would enhance bleaching effects and reduce hair damage. The above process is a way to get great results in selecting a bleaching agent. It is anticipated that hair damage could be reduced during hair bleaching based on the above results.

• Restorative Dentistry and Endodontics
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• v.48 no.3
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• pp.26.1-26.12
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• 2023

Objective: This in vitro study aimed to evaluate the effects of different whitening toothpastes on a composite resin during at-home bleaching with 10% carbamide peroxide. Materials and Methods: Sixty samples (7 mm × 2 mm) were used for color and roughness analyses, while another 60 samples (3 mm × 2 mm) were utilized to assess microhardness. The factors analyzed included toothpaste, for which 5 options with varying active agents were tested (distilled water; conventional toothpaste; whitening toothpaste with abrasive agents; whitening toothpaste with abrasive and chemical agents; and whitening toothpaste with abrasive, chemical, and bleaching agents). Brushing and application of whitening gel were performed for 14 days. Surface microhardness (SMH), surface roughness (Ra), and color (ΔL^*, Δa^*, Δb, ΔE^*_ab, and ΔE₀₀) were analyzed. The Ra and SMH data were analyzed using mixed generalized linear models for repeated measures, while the color results were assessed using the Kruskal-Wallis and Dunn tests. Results: Between the initial and final time points, all groups demonstrated significant increases in Ra and reductions in SMH. No significant differences were found between groups for SMH at the final time point, at which all groups differed from the distilled water group. Conventional toothpaste exhibited the lowest Ra, while whitening toothpaste with abrasive agent had the highest value. No significant differences were observed in ΔL^*, Δa^*, and Δb. Conclusions: While toothpaste composition did not affect the color stability and microhardness of resin composite, combining toothbrushing with whitening toothpaste and at-home bleaching enhanced the change in Ra.

• Textile Coloration and Finishing
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• v.8 no.2
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• pp.35-42
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• 1996

Peroxodisulfates are being developed as low temperature bleaching agents for cotton fabrics to save the thermal energy. In this research we used the colar difference meter to determine the whiteness which peroxide booster will possibly make an effect on cotton fabric at the low temperature process using consist of temperature with different conditions agents, such as sodium hydroxide, sodium peroxodisulfate and potassium peroxodisulfate. The peroxide bleaching follows a laboratory experiments, using a statistical plan for three variables: the concentrations of hydrogen peroxide and sodium hydroxide and the temperature of bathing. The purpose of this research was to use the response surface analysis method to evaluate the relative importance of factors providing optimum whiteness. A ridge analysis of the data on whiteness response results in 3-D response surface diagrams for optimizing the concentrations of hydrogen peroxide and sodium hydroxide at about 42~52$^{\circ}C$.

• Proceedings of the KACD Conference
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• 2001.11a
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• pp.591.1-591
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• 2001

This study was performed to evaluate internal bleaching effect of various bleaching agent on discolored nonvital teeth. 40 Human teeth were intentionally discolored with erythrocytes of human blood and randomly divided into 4 groups: 10% carbamide peroxide gel (Opalescence, Ultradent, U.S.A.); 15% carbamide peroxide gel; sodium perborate (Duksan pure chemical Co., Korea) with distilled water; sodium perborate with 30% hydrogen peroxide (Duksan pure chemical Co., Korea).(omitted)

• Textile Coloration and Finishing
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• v.24 no.1
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• pp.27-32
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• 2012

Generally, hair treatments by complementary actions to give a sense of activity are permanent setting, dyeing, and bleaching, etc. In this study, we investigated the wave formation ability and hair damage occuring in permanent setting and bleaching process. The wave formation ability was evaluated by the differences of length and curl diameter after permanent setting. And the hair damage was also evaluated by the protein release ability and SEM of hair. The bleached hair immediately after permanent setting treatment has better wave formation ability, but much more damaged than the bleached hair after rinsing thoroughly with warm water. It was considered that the chain of hair keratin broke down easily by the bleaching action in the existence of permanent setting agents.

• Journal of Korean society of Dental Hygiene
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• v.8 no.4
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• pp.11-18
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• 2008

The purposes of this study were to examine the effect of 35% Carbamide Peroxide(CP) bleaching agent on the changes in physical and chemical characteristics of tooth. The effect of bleaching agent on enamel was analyzed using Hardness test, SEM and EDS. The microhardness between bleached groups after bleaching showed statistically significant difference according to the paired t-test. The bleached enamel surface showed apparent morphological changes compared to the enamel, which was stored in distilled water only. The difference of the total mineral contents for the distilled water and Carbamide Peroxide did not show statistical significance. These results demonstrated that bleaching using 35% Carbamide Peroxide were adversely affects application time of experimental group and may the safety of using these agents for a short time in dentist-monitored bleaching.

• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.169-179
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• 1994

The purpose of this study was to compare and evaluate the bleaching efficacy of three nonvital bleaching techniques: Walking bleaching, Walking bleaching and heat application, and Walking bleaching and bleaching light application. 36 extracted anterior teeth with intact crowns were immersed in 5 % sodium hypochlorite solution for twenty-four hours to loosen extrinsic debris. Lingual access openings were prepared in all teeth and the pulps were extirpated. The teeth were stored in 5% sodium hypochlorite for twenty-four hours to open the dentinal tubules and they were stained via whole blood. Once the teeth were stained, they were evaluated with Colorimeter. The teeth in each group were ranked from lightest to darkest and divided equally into three experimental groups in which the following bleaching techniques were used. Intracoronal base was placed 2mm below cementoenamel junction. Group 1 Walking bleaching (Superoxol + Sodium perborate) Group 2 Heat application + Walking bleaching (Superoxol+Sodium perborate) Group 3 Light application+Walking bleaching (Superoxol+Sodium perborate) The bleaching agents were changed every 3 days and the teeth were bleached for a total of 14 days. The teeth were evaluated with Colorimeter before the start of any bleaching and on day 14. The results were as follows: 1. At the end of 14 days, all the sample teeth demonstrated the increase of Lightness Index at cervical 1/3 of crown (p<0.05) Lightness Index was significant difference in group 2 and 3, but there were some minor differences among groups (p>0.05). 2. In all groups, there was significant difference in red chromacity (p<0.05), but there were some minor differences among groups (p>0.05). 3. In all groups, there was no significant difference in yellow chromacity (p>0.05).

• Restorative Dentistry and Endodontics
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• v.26 no.5
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• pp.399-408
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• 2001

Tooth bleaching has been prevailing recently for its ability to recover the color and shape of natural teeth without reduction of tooth material. However, it has been reported that bleaching procedure adversely affects the adhesive bond strength of composite resin to tooth. At the same time the bond strength was reported to be regained by application of some chemical agents. The purpose of this in vitro study was to investigate the effect of the removal of residual peroxide on the composite- enamel adhesion and also evaluated fracture mode between resin and enamel after bleaching. Sixty extracted human anterior and premolars teeth were divided into 5 groups and bleached by combined technique using of office bleaching with 35 % hydrogen peroxide and matrix bleaching with 10% carbamide peroxide for 4 weeks. After bleaching, the labial surfaces of each tooth were treated with catalase, 70% ethyl alcohol, distilled water and filled with composite resin. Shear bond strength was tested and the fractured surfaces were also examined with SEM. Analysis revealed significantly higher bond strength values. (p＜0.05) for catalase-treated specimens, but water-treated specimens showed reduction of bond strength, alcohol- treated specimens had medium value between the two groups(p＜0.05). The fracture mode was shown that the catalase group and the alcohol group had cohesive failure but the water sprayed group had adhesive failure. It was concluded that the peroxide residues in tooth after bleaching seems to be removed by gradual diffusion and the free radical oxygen from peroxide prevents polymerization by combining catalyst in the resin monomer. Therefore it may be possible to eliminate the adverse effect on the adhesion of composite resin to enamel after bleaching by using water displacement solution or dentin bonding agent including it for effective removal of residual peroxide.

• Journal of Digital Convergence
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• v.15 no.9
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• pp.533-541
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• 2017

In the rapidly changing 21st century, image management has become more important. Under these circumstances, as a lot of hair colors and beaching agents are used to create diverse hair colors, hair damage resulting from frequent chemical hair coloring has been inevitable. This study investigated how to reduce morphological changes in hair and hair damage after dividing hair into healthy hair('Group A') and damaged hair('Group B'), using the following bleaching agents: basic bleaching agent(a), beaching agent diluted with water(b), oil ingredient-added bleaching agent(c), water-shampoo mixed bleaching agent(d). The results found that even though hair damage can be prevented by a bleaching agent diluted with a mixture of diverse additives, there were better effects on hair texture in both 'Group A(4.83)' and 'Group B(4.41)' at a sensory test when hair was bleached with an addition of Camellia oil, according to blinded experiment, in particular. As a result, hair damage could be reduced. Therefore, this study expects that hair bleaching with an addition of Camellia oil to the mixture of a bleaching agent would bring the development of diverse new materials which can minimize hair damage as well as regulate hair brightness and make a contribution to the development of cosmetology market.

• Journal of Korean society of Dental Hygiene
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• v.10 no.3
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• pp.473-481
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• 2010

Objectives : To evaluate the effect of fluoride application on the color and microhardness of bleached enamel and compare it to that of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) application. Methods : Twenty freshly extracted human adult molar were each sectioned into halves, the specimens divided and treated according to five experimental groups: Group 1, treatment with 10% carbamide peroxide (CP) bleaching agent; Group 2, treatment with 10% CP followed by a 1.23% fluoride gel application; Group 3, treatment with 10% CP followed by a 2.23% sodium fluoride varnish application; Group 4, treatment with 10% CP followed by a 0.11% sodium fluoride gel application; Group 5, treatment with 10% CP followed by a CPP-ACP gel application. All groups were treated 6 h per day for 14 days then immersed in distilled water for 2 weeks. Changes in enamel color were evaluated on Baseline and Day 14. Microhardness were evaluated on Baseline, Days 7 and 14. Statistical analysis was performed using one-way ANOVA and post-hoc Tukey tests. Results : All the bleached enamel specimens revealed increased whiteness and overall color value. Group 1 showed the lowest microhardness values than that of Groups 2, 3, 4 and 5. In all groups, the hardness of tooth after bleaching showed a significant decrease in the microhardness as compared with the one prior to tooth bleaching. The specimens treated with remineralizing agents showed relatively less reduction in enamel microhardness than control group. Conclusions : The addition of fluoride and CPP-ACP did not impede the whitening effect. The use of remineralizing agents during bleaching treatment can significantly enhance the microhardness of bleached enamel.