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Updated: May 19, 2026
09:58
Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
Hydrogen peroxide whitens teeth by oxidizing the organic structure.
Hazem Eimar1, Ryan Siciliano, Mohamed-Nur Abdallah
1Faculty of Dentistry, McGill University, Montreal, QC H3A0C7, Canada.
Journal of Dentistry
|August 29, 2012
Summary
Tooth bleaching whitens teeth by oxidizing the organic matrix, not by altering mineral or organic content. This clarifies the mechanism, limitations, and disadvantages of peroxide-based tooth whitening procedures.
Area of Science:
- Dental Science
- Biochemistry
- Materials Science
Background:
- The precise mechanism by which peroxide oxidizers whiten teeth remains unclear.
- It is debated whether bleaching involves deproteinization, demineralization, or oxidation of tooth tissues.
Purpose of the Study:
- To elucidate the mechanism of tooth bleaching.
- To identify which chemical components of tooth enamel are affected by bleaching agents.
Main Methods:
- Sixty human teeth were treated with deproteinizing (NaOH), demineralizing (EDTA), oxidizing (H2O2) solutions, or distilled water.
- Teeth were also pre-treated with deproteinizing or demineralizing solutions before oxidation.
- Changes in enamel elemental ratios, crystallinity, and shade were analyzed using EDS, Raman spectroscopy, and spectrophotometry.
Main Results:
- Oxidation (H2O2) significantly increased tooth lightness (19.9 ± 6.5°).
- Demineralization decreased lightness (-8.5 ± 5.6°), while deproteinization increased it (4.8 ± 2.7°).
- Oxidizing demineralized teeth further increased lightness, but oxidizing deproteinized teeth did not significantly alter shade parameters.
Conclusions:
- Hydrogen peroxide whitens teeth primarily by oxidizing the organic matrix.
- Bleaching does not significantly alter the relative organic and inorganic content of tooth enamel.
- Findings provide clinical insights into the mechanism, limitations, and disadvantages of tooth bleaching.
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