Oxidative Iodination of Aromatic Amides Using Sodium Perborate or Hydrogen Peroxide with Sodium Tungstate†

Objective: to measure pH values of bleaching agents that are indicated to intracoronal bleaching technique in different time intervals. Methods: Each group (G) received five samples (n=5): G1 – distilled water (AD); G2 – hydrogen peroxide (H2O2) 30%; G3 – sodium perborate (PbS) + AD; G4 – PbS + H2O2 30%; G5 – sodium percarbonate (PcS) + AD; and G6 – PcS + H2O2 30%. pH values were stated using a digital pHmeter, in different time intervals: immediately after handling (T0), 24 hours (T1) and 168 hours after handling (T2). The results were submitted to statistical analysis through Kruskal-Wallis and Mann Whitney tests, in this order, allowing multiple comparisons among the groups. To verify the effect of time in each group, Friedman test was applied. Results: In the evaluation of the effect of time in each group, it was observed that G2 presented acid behavior, while the other groups exhibited values close to neutrality or alkaline. Conclusions: H2O2 30% was the only agent that showed acidic behavior in every evaluation time. Meanwhile, PcS + H2O had the highest pH values.

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An in-vitro Comparison of the Bleaching Efficacy of 35 Percent Carbamide Peroxide with Established Intracoronal Bleaching Agents

Journal of Dentistry and Oral Sciences ◽

10.37191/mapsci-2582-3736-3(1)-062 ◽

2020 ◽

Author(s):

Nandita Bansal

Keyword(s):

Hydrogen Peroxide ◽

Sodium Perborate ◽

Distilled Water ◽

Carbamide Peroxide ◽

Human Teeth ◽

Anterior Teeth ◽

Group I ◽

Group Ii ◽

Control Evaluation

Introduction: Intracoronal bleaching is the simplest, least invasive, and least expensive means available to lighten non-vital discolored teeth. The objective of the study: To evaluate the intra coronal bleaching efficacy of 35% Carbamide peroxide relative to 35% Hydrogen peroxide and Sodium perborate using artificially stained extracted human teeth. Materials and Methods: Eighty extracted human permanent maxillary and mandibular anterior teeth and single-rooted premolars were artificially stained using whole human blood and root canal treatment was completed. They were bleached twice 7 days apart using: Group I (n=20) – 35% Carbamide peroxide gel, Group II (n=20) – 35% Hydrogen peroxide gel, Group III (n=20) – 2 gm Sodium perborate mixed with per ml of distilled water, Group IV (n=20)– Distilled water only (control). Evaluation of shade was performed on day 0,7,14. Results: On day 7, In Groups I and Group II, there was a reduction in the shade by 2 vita tab positions, whereas Group IIIlightened by 1-tab position only. On day 14, CP and HP lightened by overall 3-tab positions and SP by 2-tab positions. There were no statistical differences between the groups on day 7 and day 14. Conclusion: 35% Carbamide peroxide, 35% Hydrogen peroxide and Sodiumperborate were equally effective for Intra coronal bleaching.

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ChemInform Abstract: KINETICS AND MECHANISM OF THE EPOXIDATION OF FUMARIC ACID WITH AQUEOUS HYDROGEN PEROXIDE CATALYZED BY SODIUM TUNGSTATE OR SODIUM MOLYBDATE

Chemischer Informationsdienst ◽

10.1002/chin.197547136 ◽

1975 ◽

Vol 6 (47) ◽

pp. no-no

Author(s):

M. AIJAZ BEG ◽

IFTIKHAR AHMAD

Keyword(s):

Hydrogen Peroxide ◽

Fumaric Acid ◽

Sodium Tungstate ◽

Sodium Molybdate ◽

Kinetics And Mechanism ◽

Aqueous Hydrogen Peroxide

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Preparation of 4-Hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl A Reinvestigation of Methods Using Hydrogen Peroxide in the Presence of Catalysts

Zeitschrift für Naturforschung B ◽

10.1515/znb-1976-1017 ◽

1976 ◽

Vol 31 (10) ◽

pp. 1376-1378 ◽

Cited By ~ 13

Author(s):

G. Sosnovsky ◽

M. Konieczny

Keyword(s):

Hydrogen Peroxide ◽

Phosphotungstic Acid ◽

Sodium Tungstate ◽

Spin Labeling ◽

Quantitative Yield ◽

Hydrogen Peroxide Solution ◽

Aqueous Hydrogen Peroxide ◽

Molar Excess

The preparation of the key intermediate for spin labeling, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (2), was reinvestigated using sodium tungstate or phosphotungstic acid with or without either Trilon or Triton B. A two-fold and a 3.5-fold molar excess of a 30% aqueous hydrogen peroxide solution was used. The oxidation of 4-hydroxy-2,2,6,6-tetramethylpiperidine (1) with a two-fold molar excess of a 30% aqueous hydrogen peroxide solution in the presence of sodium tungstate alone, under vigorous stirring for two hours, is the superior method (A) for the preparation of 2 in virtually quantitative yield.

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The hydrolysis of the bonds between fibre reactive dyes and cellulose by sodium perborate and hydrogen peroxide solutions H90 V 3

Dyes and Pigments ◽

10.1016/0143-7208(80)80011-8 ◽

1980 ◽

Vol 1 (2) ◽

pp. 121-137 ◽

Cited By ~ 5

Author(s):

Ian D. Rattee ◽

K.F. So

Keyword(s):

Hydrogen Peroxide ◽

Reactive Dyes ◽

Sodium Perborate ◽

Hydrolysis Of

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Kinetics of the oxidation of dimethyl sulfoxide with aqueous hydrogen peroxide catalyzed by sodium tungstate

Canadian Journal of Chemistry ◽

10.1139/v81-104 ◽

1981 ◽

Vol 59 (4) ◽

pp. 718-722 ◽

Cited By ~ 20

Author(s):

Yoshiro Ogata ◽

Kazushige Tanaka

Keyword(s):

Hydrogen Peroxide ◽

Dimethyl Sulfoxide ◽

Sodium Tungstate ◽

Catalytic Amount ◽

Active Oxygen ◽

Probable Mechanism ◽

Polarographic Study ◽

Aqueous Hydrogen Peroxide ◽

First Order ◽

Kinetics Of

The oxidation of dimethyl sulfoxide (DMSO) by hydrogen peroxide in the presence of a catalytic amount of sodium tungstate (Na2WO4) has been studied kinetically by means of iodometry of hydrogen peroxide. The reaction is first-order with respect to the substrate and the catalyst, but independent of the concentration of hydrogen peroxide which is present in excess of the catalyst. The polarographic study implies that in solutions two main kinds of peroxytungstic acids (H2WO5 and H2WO8) are formed which contain active oxygen in ratios (active oxygen):(Na2WO4) of 1:1 and 4:1, respectively. The effect of acidity on the oxidation rate and a probable mechanism involving a rate-determining attack of peroxytungstic acids are discussed.

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Management of intrinsic discoloration using walking bleach technique in maxillary central incisors

Medicine and Pharmacy Reports ◽

10.15386/cjmed-852 ◽

2018 ◽

Vol 91 (2) ◽

pp. 229-233 ◽

Cited By ~ 1

Author(s):

Sanket Hans Pandey ◽

Pallav Mahesh Patni ◽

Pradeep Jain ◽

Arpita Chaturvedi

Keyword(s):

Hydrogen Peroxide ◽

Glass Ionomer Cement ◽

Invasive Procedure ◽

Invasive Technique ◽

Sodium Perborate ◽

Glass Ionomer ◽

Barrier Material ◽

Non Invasive ◽

Operative Complications ◽

Ionomer Cement

Introduction. Non-vital bleaching is a non-invasive technique to treat the intrinsic discoloration of teeth of several etiologies. Hydrogen peroxide and sodium perborate are commonly used bleaching agents.Aim. The aim of this case report is to demonstrate the non-vital bleaching technique in maxillary anterior teeth.Method. Maxillary central incisors were isolated with rubber dam and root canal treatment was performed. Barrier space preparation was done using a heated instrument. Glass ionomer cement was used a barrier material. Mixture of hydrogen peroxide and sodium perborate was placed in the canal and sealed with intermediate restorative material. After 1 week, the procedure was repeated to achieve the desired results.Conclusion. Non-vital bleaching is a minimally invasive procedure to restore the esthetics of a discolored non-vital tooth. However, care should be taken to prevent any post-operative complications.

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