• Journal of Periodontal and Implant Science
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• v.24 no.2
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• pp.433-440
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• 1994

The purpose of this investigation was to study the efficacy and safety of 6% hydrogen peroxide gel as a daily home tooth bleaching gel. The subjects consisted of 20 male dental students representing a variety of acquired stain and each subject participated for a 4-week period. Tooth color analysis(Shade determination), sulcus bleeding index, probing depth and probing attachment level were done and recorded at baseline and at the end of each week of study. The results indicated that home bleaching gel containing 6% hydrogen peroxide was effective and caused no gingival inflammation. Sulcus bleeding index, probing depth and probing attachment level showed no change. In conclusion, 6% hydrogen peroxide gel is an effective and safe agent for daily home tooth bleaching.

• Korean Journal of Heritage: History & Science
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• v.44 no.4
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• pp.130-141
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• 2011

This paper examined the bleaching effect of the two types of gel made with neutralizing agent such as sodium meta silicate gel & triethylamine gel mixed with carbopol resin 940 & 934 which has thickness effect in broad pH region and mixed with 10% hydrogen peroxide. Sodium meta silicate gel(1.6g included) provided pH 10, the most suitable environment for bleaching. The result of comparison of the baseline colour changes(${\Delta}E*ab$) and colour changes according to time(${\Delta}E*ab$) is as following. Group1(carbopol 940, sodium meta silicate, Urea Hydrogen Peroxide) showed 112% efficiency at CS-2; 63.3% at CS-4; 87.4% at CS-6. Group2(carbopol 934, sodium meta silicate, Urea Hydrogen Peroxide) showed 77.3%, 67.3%, 109.6% at CS-8, CS-10, CS-12 respectively; CT-1, CT-3, CT-5 of Group3(carbopol 940, triethylamine, Urea Hydrogen Peroxide) showed 36.8%, 73.2%, 74%; In Group4(carbopol 934, triethylamine, Urea Hydrogen Peroxide), efficiency of CT-6, CT-8, and CT-10 was 81.7%, 95.4%, and 95.7%. The paper showed that various concentration of neutralizing agent such as sodium meta silicate and triethylamine have bleaching effect. Viscosity of the gel including sodium meta silicate was higher than the gel including triethylamine. High viscosity helps the bleaching gel sit on the smooth slope of the ceramics. As a result, sodium meta silicate is considered to provide thickening and bleaching effect required in producing 10% hydrogen peroxide gel.

• International Journal of Aeronautical and Space Sciences
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• v.15 no.2
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• pp.199-204
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• 2014

An experimental investigation on the rheological behavior of gelled hydrogen peroxide at different ambient temperature (283.15, 293.15 and 303.15 K) was carried out in this study. The gel propellant was rheologically characterized using a rheometer, in the shear rate ranges of 1 to $20s^{-1}$, and 1 to $1000s^{-1}$. Hydrogen peroxide gel was found to be thixotropic in nature. The apparent viscosity value with some yield stress (in-case of shear rate 1 to $20s^{-1}$) drastically fell with the shear rate. In the case of the shear rate range of 1 to $20s^{-1}$, the apparent viscosity and yield stress of gel were significantly reduced at higher ambient temperatures. In the case of the shear rate range of 1 to $1000s^{-1}$, no significant effect of varying the ambient temperature on the gel apparent viscosity was observed. The up and down shear rate curves for hydrogen peroxide gel formed a hysteresis loop that showed no significant change with variation in temperature for both the 1 to $20s^{-1}$ and the 1 to $1000s^{-1}$ shear rate ranges. No significant change in the thixotropic index of gel was observed for different ambient temperatures, for both low and high shear rates. The gel in the 1 to $20s^{-1}$ shear rate range did not lead to a complete breakdown of gel structure, in comparison to that in the 1 to $1000s^{-1}$ shear rate range.

• Restorative Dentistry and Endodontics
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• v.27 no.4
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• pp.441-447
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• 2002

The bleaching of discolored nonvital teeth is conservative treatment that satisfy the cosmetic desire. The most common method for this treatment, walking bleaching, is using 30% hydrogen peroxide and sodium perborate. Many alternatives are suggested for preventing the external cervical root resorption that is the common complication of the nonvital teeth bleaching with 30% hydrogen peroxide The same extent of oxidation reactions as that resulted by the bleaching with the application of 30% hydrogen peroxide and sodium perborate can also be acquired more safely by materials that contain 10% carbamide peroxide, used primarily for the bleaching of vital teeth. Therefore, this study was performed to evaluate the efficacy of 10% and 15% carbamide peroxide bleaching gel in nonvatal teeth bleaching. The internal bleaching of intentionally discolored teeth was performed in vitro with 10% carbamide peroxide (Group 1), 15% carbamide peroxide (Group 2), mixture of distilled water and sodium perborate (Group 3), and mixture of 30% hydrogen peroxide and sodium perborate (Group 4). The bleaching materials were refreshed following 3, 6, 9 and 12 days. To evaluate the bleaching effect, the color change of the crowns was measured at 1, 2, 3, 4, 7 and 15 days of bleaching using the colorimeter. The results were as follows：1. L$^*$ and $\Delta$E$^*$ values were increased with time in all bleaching agents (p<0.01). 2. There was no significant difference in L$^*$ and $\Delta$E$^*$ value among bleaching agents. 3. $\Delta$E$^*$ value higher than 3 was shown after 3 days of bleaching with 10% carbamide peroxide gel, 1 day with 15% carbamide poroxide gel, 4 days with mixture sodium perborate and distilled water and 4 days with mixture sodium perborate and 30% hydrogen peroride, respectively. These results revealed that the use of 10% and 15% carbamide peroxide bleaching gel in non-vital teeth bleaching is as effective as mixture of distilled water and sodium perborate and mixture of 30% hydrogen peroxide and sodium perborate. Accordingly, carbamide peroxide could be used clinically to bleach discolored non-vital teeth.

• Proceedings of The Korean Society of Health Promotion Conference
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• 2007.04a
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• pp.151-153
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• 2007

• Journal of dental hygiene science
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• v.11 no.4
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• pp.375-380
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• 2011

This study evaluated whether fluoride treatment can affect recovery of the irregularity of enamel surface after tooth whitening with a high concentration of hydrogen peroxide (HP) activated by plasma arc light. A total of 36 bovine teeth stained with coke were used in this experiment. The specimens were classified into following three groups (two different commercial plasma arc groups and a control group without light curing source): (1) 35% HP gel only, (2): 35% HP gel and Plasma arc A, and (3) 35% HP gel and Plasma arc B. To measure color changes and surface morphologies before and after the bleaching, colorimeter and scanning electron microscopy were used, respectively. When the specimens were bleached with hydrogen peroxide and plasma arc lights, the bleaching effect was greater than when only hydrogen peroxide gels were used (Kruskal-Wallis test, p<0.05). In addition, plasma arc B showed the more color changes than plasma arc A (Bonferroni post-hoc test, p<0.05). The surfaces of the teeth treated with fluoride gel after the whitening treatment came to be smooth. Therefore, the results of this study suggested that the fluoride application for patients who got tooth whitening therapy with a high concentration of hydrogen peroxide gels activated by plasma arc light will be effective to recover rough enamel surfaces.

• Restorative Dentistry and Endodontics
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• v.35 no.3
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• pp.198-210
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• 2010

This study evaluated the safety of an office bleaching gel (RemeWhite, Remedent Inc., Deurle, Belgium) containing 30% hydrogen peroxide. 37 volunteers were received office bleaching with the RemeWhite for 3 times at one visit, total 2 visits. As control group, the same gel in which hydrogen peroxide was not included was applied to 34 volunteers with the same protocol. There was no difference between experimental group and control group using electric pulp test. In the result of gingival inflammation index and tooth sensitivity test, there was mild pain response in experimental group but it disappeared as time went by. Therefore, safety of the office bleaching gel containing 30% hydrogen peroxide was confirmed.

• Korean Journal of Microbiology
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• v.31 no.2
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• pp.166-174
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• 1993

Streptomyces coeUc%r (Muller) cells were treated with $100 \mu$M hydrogen peroxide for I hour and proteins synthesized during hydrogen peroxide stress were labeled with L-[$^{35}S$]-methionine. Total cellular proteins were extracted and analyzed by two-dimensional polyacrylamide gel electrophoresis. In exponential growth phase, synthesis of about 100 proteins was increased by hydrogen peroxide treatment. These proteins were named as Pin (£eroxide-inducib]e) proteins and classified into 4 subgroups according to their induction time after hydrogen peroxide treatment. About 60 of them were found to be induced within 20 minutes and maintained throughout I hour of treatment. In stationary growth phase. synthesis of 62 proteins was increased by hydrogen peroxide and 21 of them were the same Pins found in exponential growth phase. Proteins from the mutants which are resistant to hydrogen peroxide were obtained in exponential growth phase and compared with those from the wild type on two-dimensional gel. The three mutants, N7, N9. and N24, were found to have higher constitutive leve]s of ]5, 17, and 15 Pin proteins respectively, than the wild type. 9 of these Pin proteins (D74.7a, E76.0c, E23.3. F50.7, F47.2a. F25.5, G39.6b, G24.0, H39.6a) increased in two of the three mutants and 3 proteins (F39.7, H6I.7. 120.8) increased in all of the three mutants. These proteins might play important roles in the response of S. coelic%r to hydrogen peroxide.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.3
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• pp.205-209
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• 2012

The objective of the present study was to establish the method of measurement of hydrogen peroxide and to estimate the anti-oxidative effect of genistein in the skin. UVB induced skin oxidation and anti-oxidative effect of genistein formulations were evaluated by determining levels of hydrogen peroxide. The mechanism involved in the determination of hydrogen peroxide is based on a color reaction between ferric ion ($Fe^{3+}$) and xylenol orange, often called FOX assay and subsequent monitoring of absorbance values of the reactant at 540 nm. The reaction was to some extent pH-dependent and detection sensitivity was greatest at pH 1.75. Genistein liposomal gel demonstrated better anti-oxidative effect with regard to lowering hydrogen peroxide levels elevated by UVB irradiation compared to genistein-suspended gel. A linear relationship has been observed between anti-oxidative effect of genistein and drug deposition in the skin tissue. Genistein liposomal gel resulting in the localization of the drug in the deeper skin led to improved anti-oxidative effect compared to genistein gel. The suggested method for evaluation of oxidation of the skin can be used as a tool to screen effective anti-oxidative agents and their delivery systems acting on the skin.

• Restorative Dentistry and Endodontics
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• v.48 no.4
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• pp.33.1-33.12
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• 2023

Objectives: This study aimed to evaluate the bleaching efficacy and hydrogen peroxide permeability in the pulp chamber by the at-home bleaching gel in protocols applied on different dental surfaces. Materials and Methods: Forty premolars were randomly into 4 groups: control group no bleaching, only application on the buccal surface (OB), only application on the lingual surface (OL) and application in buccal and lingual surfaces, simultaneously (BL). At-home bleaching gel (White Class 7.5%) was used for the procedure. The bleaching efficacy was evaluated with a digital spectrophotometer (color change in CIELAB [ΔE_ab] and CIEDE 2000 [ΔE₀₀] systems and Whitening Index for Dentistry [ΔWI_D]). The hydrogen peroxide permeability in the pulp chamber (㎍/mL) was assessed using UV-Vis spectrophotometry and data were analyzed for a 1-way analysis of variance and Tukey's test (α = 0.05). Results: All groups submitted to bleaching procedure showed bleaching efficacy when measured with ΔE_ab and ΔE₀₀ (p > 0.05). Therefore, when analyzed by ΔWI_D, a higher bleaching efficacy were observed for the application on the groups OB and BL (p = 0.00003). Similar hydrogen peroxide permeability was found in the pulp chambers of the teeth undergoing different protocols (p > 0.05). Conclusions: The application of bleaching gel exclusively on the OB is sufficient to achieve bleaching efficacy, when compared to BL. Although the OL protocol demonstrated lower bleaching efficacy based on the ΔWI_D values, it may still be of interest and relevant in certain clinical scenarios based on individual needs, requiring clinical trials to better understand its specificities.