Different Concentrations Of Hydrogen Peroxide Research Articles

Effect of whitening toothpastes with different hydrogen peroxide concentrations: Penetration into the pulp chamber and color change

ObjectivesThis study evaluated the efficacy of simulated brushing with toothpastes containing different concentrations of hydrogen peroxide (HP) in pulp chamber penetration and color change. Also, physical-chemical properties (concentration, pH and viscosity) were evaluated. MethodsForty-nine premolars were divided into seven groups (n = 7): untreated (control); whitening gel (White Class 6 %, 6 %BG) with one 90 min application (6 %BG 90 min) and 14 applications of 90 min (6 %BG 14×90 min); toothpastes (Colgate Luminous White Glow 3 %, 3 %TP; Crest 3D White Brilliance 4 %, 4 %TP; Colgate Optic White Pro-Series 5 %, 5 %TP) and 6 %BG toothbrushing for 14 applications of 90 s. HP penetration into the pulp chamber was measured through UV–Vis spectrophotometry and color change with a spectrophotometer (ΔEab, ΔE00, and ΔWID). Initial concentration, pH, and viscosity were measured through Titration, Digital pH-meter, and Rheometer, respectively. Statistical analysis used one-way ANOVA and Tukey's test (α = 0.05). Results6 %BG (14×90 min) and 4 %TP groups showed acidic pH and higher concentrations of HP in the pulp chamber compared to the other groups (p < 0.05). On the other side, 3 %TP and 5 %TP groups showed alkaline pH, higher viscosity between the toothpastes and lower HP penetration (p < 0.05). The 6 %BG AH (14×90 min) group exhibited the most significant color change (ΔEab, ΔE00, and ΔWID) (p < 0.05). ConclusionsBrushing with whitening toothpaste with an acidic pH leads to greater HP penetration into pulp chamber; but, even when a high concentrated HP whitening toothpaste was used, a lower whitening effect was observed when compared to a two-week at-home bleaching. Clinical SignificanceWhitening toothpastes containing up to 5 % HP produced lower whitening effect than two-week at-home bleaching. Additionally, HP was detected within the pulp chamber which can potentially impact in tooth sensitivity.

Influence of blue and violet LED and infrared laser on the temperature of bleaching protocols in different concentrations of hydrogen peroxide

BackgroundThe photo-acceleration of bleaching gels by lights has been extensively researched. However, the induced temperature increase during this process needs to be further evaluated to prevent damage to the dental pulp. Therefore, the objective of this study was to evaluate the surface and intrapulpal temperature kinetics of different concentrations of hydrogen peroxide (HP) gels photo-accelerated by blue or violet light and infrared laser. MethodsThe whitening gels at concentrations of HP35, HP15, and HP6 % were irradiated with blue and violet LED/laser on the surface of a human canine tooth. The surface temperature variation (∆Ts) was evaluated using a pH meter, while the intrapulpal temperature variation (∆Ti) was assessed using a digital thermometer at intervals of 1, 15, and 30 min. Statistical analysis was conducted using a Two-way repeated measures ANOVA test, and Bonferroni post-test was applied at a significance level of 5 %. ResultsAll violet LED photo-accelerated groups showed a higher increase in ∆Ts compared to the blue LED/laser groups. However, there were no significant differences between the groups for ∆Ti. ConclusionAlthough the photo-acceleration of HP35 and HP15 % gels with violet LED/laser has a greater increase in surface temperature compared to HP6 % gel, the different light systems do not significantly increase the intrapulpal temperature.

Effect of different concentrations of hydrogen peroxide on indigenous bull sperm motility

Effect of different concentrations of hydrogen peroxide on indigenous bull sperm motility

Dissolution of contaminant Zr-DBP and corrosion of stainless steel by dissolved solution

In the nuclear spent fuel reprocessing, zirconium dibutyl phosphate (Zr-DBP) is deposited on the surface of stainless steel equipment, making spent fuel reprocessing difficult. Therefore, in this study, hydrazine carbonate ((N2H5)2CO3) was used to dissolve Zr-DBP. The effects of solid–liquid ratio, different mass fractions of (N2H5)2CO3 solutions, and (N2H5)2CO3 solutions containing different concentrations of hydrogen peroxide (H2O2) on the dissolution of Zr-DBP were investigated. The corrosion rates of different dissolution solutions on stainless steel were also investigated. When the mass fraction of (N2H5)2CO3 in solution was increased from 1 % to 20 %, the concentration of Zr(IV) at dissolution equilibrium increased from 1.05 g/L to 1.61 g/L, respectively. When the dissolution temperature was kept in the range of 25 °C to 65 °C, the increasing temperature promoted the dissolution of Zr-DBP. The presence of H2O2 induced the production of the white precipitates zirconium hydroxide (Zr(OH)4). In addition, the corrosion rate of stainless steel gradually increased from 0.00153 mm/a to 0.0138 mm/a when the concentration of H2O2 in the (N2H5)2CO3 solution was increased from 0 M to 1.5 M. The dissolution ability of Zr-DBP in different carbonate solutions was (N2H5)2CO3 ≥ ammonium carbonate ((NH4)2CO3) > sodium carbonate (Na2CO3) ≥ potassium carbonate (K2CO3).

Novel oxidation indicator films based on natural pigments and corn starch/carboxymethyl cellulose

The existing oil oxidation detection methods are unsuitable for consumers to identify oil oxidation in a domestic setting. This study aims to develop indicator films detecting the degree of lipid oxidation with the naked eye. Purple sweet potato pigment (PSP) was chosen as a color indicator due to its response to hydrogen peroxide. The novel oxidation indicator films were prepared using corn starch, carboxymethyl cellulose (CMC), and varying concentrations of PSP. Fourier transform infrared spectroscopy spectra and scanning electron microscopy analysis confirmed the successful dispersion of PSP in the films. Thermal stability, light resistance, ultraviolet light resistance, mechanical resistance, and flexibility of films containing PSP were improved, enhancing the potential application in detecting oxidized substances. All the films exhibited noticeable color changes when exposed to different concentrations of hydrogen peroxide. These differences were more pronounced with higher levels of PSP. When these films were used to determine the degree of lipid oxidation, the ∆E value of the CS-PSP-0.25 % film showed a linear relationship (R2 = 0.929) with the peroxide value, unlike other films. Therefore, it is reliable to infer the peroxide value of edible oil by observing the color of the films, which helps customers avoid consuming expired oils.

Catalytic epoxidation of palm oleic acid by heterogeneous catalysts: Optimization and kinetic model

AbstractEpoxidized vegetable oils can produce a natural‐based polymer product as chemical reaction intermediates, plasticisers, and stabilizers in polyvinyl chloride. This study aims to identify the effects of using different concentrations of hydrogen peroxide and the effect of different molar ratios of hydrogen peroxide on relative conversion to oxirane. Epoxidized palm oil was produced in situ using performic acid as epoxidation agents and titanium dioxide as a catalyst. The results indicated that a higher concentration of hydrogen peroxide at 50% concentration and the ratio of 2:1 of hydrogen peroxide to palm oil used in the in situ epoxidation of had provided a higher relative conversion to oxirane (50%) in reaction time (70 min). Fourier transformation infrared spectroscopy revealed the presence of an oxirane group at 1200 cm−1. Numerical kinetic modeling was developed with applied genetic algorithm optimization to find the process model that fit experimental data. Then, the kinetic rate, k parameters obtained k11 = 0.031 mol L−1 min−1, k12 = 3.159 mol L−1 min−1, k2 = 2.620 mol L−1 min−1 for epoxidation palm oil, and k3 = 1.19 × 10−5 mol L−1 min−1 in degradation process.

Preclinical EIS Study of the Inflammatory Response Evolution of Pure Titanium Implant in Hank's Biological Solution.

Pure titanium (Ti) is investigated in a pre-clinical study in Hank's biological solution using electrochemical methods, open circuit potential, and electrochemical impedance spectroscopy to highlight the time effect in extreme body conditions, such as inflammatory diseases, on degradability due to corrosion processes occurring on the titanium implant. Electrochemical impedance spectroscopy (EIS) data are presented as Nyquist and Bode plots. The results show the increasing reactivity of titanium implants in the presence of hydrogen peroxide, which is an oxygen-reactive compound that describes inflammatory conditions. The polarization resistance, which results from electrochemical impedance spectroscopy measurements, declined dramatically from the highest value registered in Hank's solution to smaller values registered in all solutions when different concentrations of hydrogen peroxide were tested. The EIS analysis provided insights into titanium's in vitro corrosion behavior as an implanted biomaterial, which could not be solely obtained through potentiodynamic polarization testing.

Influence of hydrogen peroxide on hatching of nauplii Artemia sp.

Nauplii of the brine shrimp Artemia sp. are the optimal starter food for many fish and crustaceans species. For this reason, technologies for their production are being improved, including the activation of cysts. The effect of different concentrations of hydrogen peroxide on hatching process a as activator was studied. Its optimal concentration has been determined; it amounts to 0.2-0.4 ml/l. The reasons for various impacts of hydrogen peroxide on different Artemia cysts are formulated. The dynamic of brine shrimp hatching with and without the activator was studied. It has been established that the addition of a hydrogen peroxide solution as an activator increases the hatching of Artemia nauplii, however, it does not impress on the rapidity of Artemia nauplii release from cysts.

Microstructural effect of different concentrations of hydrogen peroxide photoactivated with LED/laser

BackgroundThe use of different concentrations of hydrogen peroxide (HP) photoactivated with LED/laser sources is common however, their influence on tooth structure is not yet fully elucidated. This study aimed to evaluate the pH, microhardness and surface roughness of different bleaching protocols photoactivated with LED/laser. MethodsForty bovine incisors were sectioned (7 × 7 × 2 mm) and randomized into four groups for analysis of pH (n = 5), microhardness and roughness (n = 10): HP35, HP6_L, HP15_L, HP35_L. The pH analysis was performed in the initial and final minute of the bleaching protocol. Microhardness and roughness were evaluated before and 7 days after the last bleaching session. Results were obtained from two-way ANOVA for repeated measures and Bonferroni post-test at a significance level of 5%. ResultsHP6_L showed higher pH and greater stability between the initial and final evaluations, while the other groups showed similar pH with reduced values in the intragroup evaluation. No differences between groups in microhardness and roughness evaluations were observed. ConclusionsAlthough HP6_L showed higher alkalinity and pH stability, none of the protocols reduced the microhardness and surface roughness of bovine enamel.

Hydrogen Peroxide Stress Induced in the Marine Cyanobacterium Synechococcus aeruginosus and Phormidium valdarianum.

Biochemical markers against hydrogen peroxide-induced oxidative stress were developed in marine cyanobacteria under standard laboratory conditions. To find out the ability to cope with different concentrations of hydrogen peroxide, two species of marine cyanobacteria including unicellular and filamentous forms were exposed for shorter duration. Synechococcus aeruginosus and Phormidium valderianum tolerated hydrogen peroxide by showing the highest growth of Superoxide dismutase in Synechococcus aeruginosus and Phormidium valderianum, catalase in Synechococcus aeruginosus, peroxidase in Synechococcus aeruginosus and Phormidium valderianum, Glutathione S-transferase in Synechococcus aeruginosus and Phormidium valderianum which were identified as biochemical markers of oxidative stress against H2O2 in marine cyanobacteria. Synechococcus aeruginosus showed new isoforms for Superoxide dismutase, catalase, peroxidase, Glutathione peroxidase, and Glutathione S-transferase and Phormidium valderianum for Superoxide dismutase, peroxidase, and Glutathione S-transferase. Synechococcus aeruginosus is suggested as the indicator species for biochemical markers against hydrogen peroxide in marine cyanobacteria. Peroxidase is suggested as biochemical enzyme marker. The present investigated on these new isoenzymes were identified as biochemical markers for oxidative stress.

Study of catalase reversibility during multiple injections of H2O2 using online measurement by FFT continuous cyclic voltammetry

This work presents a new method for the determination of catalase activation reversibility upon injection of different concentrations of hydrogen peroxide (H2O2) based on fast Fourier transformation continuous cyclic voltammetry (FFTCCV). The spectroscopic and cyclic voltammetric data demonstrated that catalase could rapidly decompose H2O2 at concentrations below 40 mM. Also, the catalase activity gradually decreased at higher concentrations of H2O2. In addition, the calculated kinetics model of suicide inhibition demonstrated that the catalase irreversibility was triggered at the concentration of 80 mM. FFTCCV data by multiple injections of H2O2 revealed that the catalase activity could be recovered at 10, 20, 40, and 60 mM after 6, 4, 3, and 2 injections of H2O2, respectively. H2O2 at concentrations above 40 mM was not fully decomposed and remained in the solution after the catalase reaction. The maximum reversibility of the catalase activity was observed for the concentration of 10 mM, when H2O2 concentration drastically decreased within a few seconds of the reaction. Our data shows that the FFTCCV method can be recruited to monitor and evaluate enzymatic reactions.

Effect the Different Concentrations of Hydrogen Peroxide and Addition Soil Amendments on Growth and Nutrient Balance in Ranunculus Asiaticus L. Grown under Salinity Conditions

An experiment was conducted in a greenhouse at research station (A) / College of Agricultural Engineering Sciences / University of Baghdad to study the impact of exogenous application of hydrogen peroxide and soil amendments (zeolite and Disper osmotic regulator) in the physiological traits of the Ranunculus asiaticus L. grown in saline soils. The experiment included three factors, soil (S) at two kinds (2.17, 5.8 dsm), soil amendments at includes 3 levels of zeolite (0,4,8 gm kg-1 soil), and two levels Disper Osmotic (1,2 gm l-1), hydrogen peroxide application (0,5,10 mmol l-1). results showed saline soils caused a significant decrease in vegetative and flowering growth, and the leaf content of N, P, K. While a significant increase in the leaf content of Na was observed, is an indicator of oxidative stress. The addition of soil amendments (M3) (1 gm l) to plants grown under salinity stress caused a significant increase in the leaf content of N, P, K and plant height, leaf area and all flowering growth characteristics. Exogenous application of hydrogen peroxide at a concentration (5 mmol l-1) had a significant effect on most of the vegetative and flowering growth characteristics.

Swimming behaviour as an alternative endpoint to assess differences in abiotic stress sensitivities between strains of Brachionus koreanus (Rotifera: Monogononta)

Brachionus plicatilis is a cosmopolitan rotifer used as a model organism in several research areas and as live food in aquaculture. Being a species complex, responses to stressors vary even among strains of the same species and, thus, the responses of one species are not representative of the whole complex. This study aimed to address the effects of extreme salinity ranges, and different concentrations of hydrogen peroxide, copper, cadmium, and chloramphenicol, in two strains of B. koreanus (MRS10 and IBA3) from B. plicatilis species complex, by assessing effects on their survival and swimming capacity. Neonates (0–4 h old) were exposed to the stressors in 48 well-microplates, for 24 and 6 h, to evaluate lethal and behavioural effects, respectively. Tested conditions of chloramphenicol did not show any effects on rotifers. The behavioural endpoint showed to be particularly sensitive to assess the effects of high salinity, hydrogen peroxide, and copper sulfate, as swimming capacity impairment was observed for both strains in the lowest concentrations used in lethal tests. Overall, results showed that IBA3 was more tolerant to the majority of stressors, comparing to MRS10, which may be due to differences in physiological characteristics, highlighting the importance of performing multiclonal experiments. Also, swimming capacity inhibition proved to be a good alternative to the classical lethality tests, being sensitive to lower concentrations and with shorter exposure periods.

Regeneration of granular activated carbon clogged in the treatment of leachates.

Landfill leachates are highly contaminated liquids and complex to treat. Two of the processes which are promising for the treatment are the advanced oxidation and adsorption methods. With the combination of the Fenton and adsorption methods, practically all the organic load of leachates can be removed; however, this combination of processes is limited due to the soon clogging of adsorbent material, which leads to high operation costs. In the present work, the results of the regeneration of clogged activated carbon are shown after the application of the Fenton/adsorption process in leachates. This research consisted of four stages: sampling and leachate characterization, clogging of the carbon through the Fenton/adsorption process, carbon regeneration through the oxidative Fenton process, and lastly, evaluation of regenerated carbon adsorption through jar and column tests. In the experiments, HCl 3M was used, and different concentration of hydrogen peroxide (0.15M, 0.2M, 0.25M) were tested at different times (16h and 30h). The activated carbon regeneration through the Fenton process and the optimal peroxide dosage was 0.15M for 16h. The regeneration efficiency was obtained from comparing the adsorption efficiency between regenerated and virgin carbon, reaching 98.27% and can be applied up to 4 times without losing regeneration efficiency. These results prove that it is possible to restore the clogged activated carbon adsorption capacity during the Fenton/adsorption process.

The mechanism of oxidative stress in keloid fibroblasts and the experimental study of early application of angiotensin-converting enzyme inhibitor.

Objective To investigate the protective effects of an angiotensin-converting enzyme inhibitor after inducing oxidative stress on keloid fibroblasts. Methods Primary keloid fibroblasts were isolated and cultured by enzyme digestion combined with the tissue adhesion method in vitro, and the third to fifth generations of cells were selected for the experiment. For 24 hours, keloid fibroblasts were treated with different concentrations of hydrogen peroxide. Different concentrations of angiotensin-converting enzyme inhibitor were added to the keloid fibroblast culture medium, and then the cells were treated with hydrogen peroxide for 24 hours. Results With the increase of hydrogen peroxide concentration, the growth of keloid fibroblasts was inhibited and the levels of malondialdehyde, superoxide dismutase, and reactive oxygen species increased gradually, accompanied by an increase in the expression of nicotinamide adenine dinucleotide phosphate oxidase and collagen I mRNA. The expression of nicotinamide adenine dinucleotide phosphate oxidase-mRNA in keloid fibroblasts and the formation of reactive oxygen species in keloid fibroblasts were induced by different concentrations of angiotensin II, and the most significant effect was at 10-5 mmol/mL. The effects of diphenyleneiodonium chloride (NOX inhibitor), N-acetylcysteine (reactive oxygen species inhibitor) and nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) RNA treatment on angiotensin II-induced nicotinamide adenine dinucleotide phosphate oxidase and collagen I increased significantly. Hydrogen peroxide and angiotensin II alone or combined can induce NADPH oxidase and reactive oxygen species expression in keloid fibroblasts. When the angiotensin-converting enzyme inhibitor was added, the expression of NADPH oxidase and reactive oxygen species in keloid induced by hydrogen peroxide and angiotensin II could be inhibited. Conclusion Oxidative stress can lead to increased expression of reactive oxygen species, NADPH oxidase and collagen I in keloid fibroblasts, suggesting oxidative stress mediates the migration of human keloid fibroblasts and extracellular matrix synthesis.

Effect of Hydrogen Peroxide on the Soil Microbial Community Structure and Growth of Malus hupehensis Rehd. Seedlings under Replant Conditions.

Apple replant disease (ARD) is common in apple production, which seriously affects the growth and development of apples. In this study, hydrogen peroxide with a bactericidal effect was used to treat the replanted soil, and the effects of different concentrations of hydrogen peroxide on replanted seedlings and soil microbiology were investigated in order to seek a green, clean way to control ARD. Five treatments were set up in this study: replanted soil (CK1), replanted soil with methyl bromide fumigation (CK2), replanted soil + 1.5% hydrogen peroxide (H1), replanted soil + 3.0% hydrogen peroxide (H2), and replanted soil + 4.5% hydrogen peroxide (H3). The results showed that hydrogen peroxide treatment improved replanted seedling growth and also inactivated a certain number of Fusarium, while the Bacillus, Mortierella, and Guehomyces also became more abundant in relative terms. The best results were obtained with replanted soil + 4.5% hydrogen peroxide (H3). Consequently, hydrogen peroxide applied to the soil can effectively prevent and control ARD.

The Effect of In-Office Bleaching with Different Concentrations of Hydrogen Peroxide on Enamel Color, Roughness, and Color Stability

The aim of this study is to evaluate the effectiveness of in-office bleaching in esthetic dentistry on the roughness and color stability of the enamel surface, using different concentrations of hydrogen peroxide (HP). Fifty human incisors were randomly divided into 5 groups (n = 10). No bleaching was performed in the control group. For these groups, concentrations of 40% HP with fluoride (F), 35% HP with calcium (Ca), 25% HP with nano-hydroxyapatite (nHA) and 18% HP with nHA were used for bleaching in the test groups. Surface roughness was assessed at baseline after bleaching occurred. Color measurements were first obtained at baseline, then after the first and second sessions of bleaching, and, finally, after the staining protocol. Scanning electron microscopy and atomic force microscopy were performed. Statistical analysis was conducted with a one-way ANOVA, followed by a post hoc Tukey's test and a paired-samples t-test (p < 0.05). All the bleaching gels used exhibited a similar color change (p > 0.05). Bleaching gels containing 18% HP with nHA and that containing 35% HP with Ca caused less surface roughness of the enamel. Of these concentrations, 25% HP with nHA caused the most surface roughness and no significant difference was observed, compared with 40% HP with F. The highest coloration after bleaching was observed in 40% HP with F and 25% HP with nHA. The lowest coloration was obtained in 35% HP with Ca and 18% HP with nHA but no significant difference was observed between them and the control group. A concentration above 18% HP does not increase the bleaching effectiveness. The results show that 18% HP with nHA and 35% HP with Ca resulted in the least increase in enamel surface roughness when compared to high-concentrate HP; however, it also prevented recoloration after bleaching.

Steam Explosion Pretreatment with Different Concentrations of Hydrogen Peroxide along with Citric Acid: A Former Step towards Bioethanol Production

The present paper focuses on the utilization of the steam explosion method for efficient pretreatment of rice straw, used as a prominent substrate for bioethanol production. Native rice straw contains abundant chemical compounds in the form of cellulose, hemicellulose, and lignin 32.4%, 57%, and 12.5%, respectively. Pretreatment with different concentrations of H2O2 (0.05%, 0.1%, 0.25%, 0.5%, 0.75%, and 1%) was used as efficient impregnating agents at an optimum temperature of 121°C at 130 kPa pressure. After pretreatment, cellulosic content increases up to 54.5% while there was a reduction in the hemicellulose and lignin content up to 46.5% and 6.7%, respectively. The morphological changes were analyzed both before and after pretreatment using FTIR, TGA, and XRD. The reducing sugar estimation was carried out using DNS reagent and the absorbance was measured using a UV spectrophotometer at 540 cm-1 wavelength. Estimated results show a reducing sugar yield of 220.05 g/l from 0.05% ( v / v ) H2O2 pretreated sample and 273.21 g/l from sample, pretreated with H2O2, citric acid in the ratio of 1 : 1 with the same previous concentration. The XRD data shows enhancement of cellulose accessibility upon pretreatment to 13.3% and thereafter reduction with an increase in the concentration of H2O2. While pretreatment with H2O2 combined with citric acid in 1 : 1 ratio shows enhanced accessibility of 19.6% than untreated rice straw. This work mainly focuses on the core objective of an efficient pretreatment method for sustainable bioethanol production through a novel approach to the production of fermentable sugar.

Optical sensor response towards hydrogen peroxide in low fat and full cream milk

Fiber Optic Displacement Sensor (FODS) categorized as one of the optical sensor based reflective intensity modulation. An intensity based sensor have been widely used in detecting various substances due to their simplicity structures. Generally for sensing principle, a pair of fiber is used to construct FODS which one of optical fiber is the transmitting fiber and another one is receiving fiber. The objective of this current work is to introduce FODS to evaluate the optical response in terms of voltage reading at different concentration of hydrogen peroxide in two different types of milk. A real-time measurement, low cost, stability, high sensitivity and simplicity of design promote a well-developed sensor in providing useful parameters in detecting hydrogen peroxide in milk. Hydrogen peroxide is an adulterated agent added in milk that can harm the consumers. Transmitive optical sensor as a function of displacement technique was developed to study the hydrogen peroxide concentrations in the range of 0 %-10 % as consuming more than 3-10 % of hydrogen peroxide can cause mild allergies reactions, stomach upset and vomiting. The output from the receiving fiber in this designated system was measured in terms of voltage reading through multimeter. The sensor shows outstanding performances of delivering 0.0007 V/% sensitivity for low fat milk and with linearity of >98 %. Whereas, the sensitivity achieved for full cream milk was 0.0005 V/% with a good linearity >97 %. The simplicity and credibility of this system offer a good opportunity in this project and also foods industry applications.

The influence of hydrogen peroxide concentration on the chemical kinetics of photo-accelerated tooth whitening

BackgroundThe bleaching procedure consists of chemical principles of free radical release that react with chromophores, which results in an amount of energy released in this process. However, the evaluation of the electrical potential generated in these protocols has not yet been thoroughly investigated in the literature. Thus, this study aimed to examine variations in pH, mV, and temperature of different concentrations of hydrogen peroxide in the presence or absence of an intermittent LED/LASER photo acceleration system. MethodsThe study was divided into six groups (n = 9) according to the concentration of hydrogen peroxide (6%, 15%, and 35%), associated or not with the photo acceleration system LED/LASER. We followed the variation of pH, mV, and temperature at 1, 5, 10, 15, and 30 min after gel manipulation. Data were evaluated by two-way ANOVA of repeated measures (α =0.05). ResultspH, mV, and temperature of the groups showed statistical differences both in the light and bleach and in the interaction between the two factors (p < 0.0001), where pH and mV were more influenced by the bleach and light factor, while the temperature was influenced by the bleach factor associated with light. HP15 presented the most significant change in pH, mV, and temperature. ConclusionThe use of LED/laser increased the temperature of the gels and altered the pH and mV kinetics of HP6 and HP15, which did not occur in HP35, possibly due to the high ionic potential linked to the concentration.