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13 Cards in this Set
- Front
- Back
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What is tooth whitening |
The procedure of restoring the natural shade of a tooth whitening it more than the natural shade. |
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Materials used for bleaching |
Hydrogen peroxide or carbamide peroxide |
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Strength of carbamide compared to hydrogen peroxide |
15% carbamide peroxide = 5 % hydrogen peroxide |
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Walking bleach technique |
Mainly used for root canal treated teeth . After GP filling, hydrogen peroxide is filled in the chamber and sealed . patient is asked to return after few days. |
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Contraindications for bleaching |
Allergy to peroxide Unrealistic Expectations of the patient Pre existing sensitive teeth Tooth cracks or exposed dentin Enamel development defects Acid erosion Receding gums Sensitive gums Defective dental restorations Tooth decay Active periapical Pathology Untreated periodontal disease Pregnant or lactating ladies Children under the age of 16 White visible fillings or crowns already present |
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Difference between hydrogen per oxide and carbamide peroxide |
H2o2 active upto 90 minutes 50% released in first 30 minutes
Carbamide peroxide active upto 8 hours 50% released in 2 hours |
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Conversion of H2o2 % to carbamide peroxide |
Multiply the h2o2% by 2.8 |
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Action site of H2o2 |
Dentin |
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Mechanism of teeth whitening |
O2 released by H2o2 decomposition acts on color absorbent chromaphore in dentin. The carbon double bonds in chromaphore is darker and o2 action breaks it down to single bond carbons which reflect light and are colorless |
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Types of stains |
Yellow or brown stains Seen in young adults. Easier to bleach
Grey stains in older adults. Slower as more calcified dentin Tetracycline fluorosis stains harder to bleach but can be done may need 6 months. Carbamide peroxide is a better choice here |
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Extrinsic and intrinsic stains |
Intrinsic stains need H2o2 to be removed. Can’t be removed by otc products |
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Speed of whitening depends on |
Concentration and contact time |
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Suggested order for teeth shades for whitening |
B1, a1, b2, d2, a2, c1, c2, d4, a3, d3 , b3, a3.5, b4, c3, a4, c4 |
