Endodontics
Course Review
Enoch Ng, DDS 2014
Internal Bleaching
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2 types of discolorations
o
Extrinsic – arising in enamel – coffee, tea, wine, etc
Can be removed via prophy or external bleaching
o
Intrinsic – originating within pulp chamber/dentin – pulp degeneration causing hemoglobin breakdown
Causes
Pulpal degeneration
Caries
Systemic drugs
Sealer/gutta percha
Bleaching Materials
HOOH – 5-35%
Carbamide peroxide – 10-15%
Sodium perborate – powder mixed with HOOH or H
2
O
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Walking Bleach Technique
o
Realistic expectations – inform patient desired shade may not be achieved
o
Take pre-op shade
o
Rubber dam isolation
o
Remove restoration and pulp horns, don’t remove excess dentin
o
Remove 3mm GP apical to CEJ, remove remaining sealer with ^OH/CP
o
Place 2-3mm barrier – Cavit, IRM, GI, or composite
Looks like a bobsled run/ski slope
Gutta Percha is NOT effective barrier to bleaching agent
o
Mix sodium perborate with distilled water or anesthetic
o
Place with amalgam carrier, place temporary
o
Recall every 7-14 days, if unsatisfactory repeat procedure (short acid etch to open dentinal tubules)
Don’t leave bleach in tooth long, risk of resorption
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Prognosis
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50% successful
o
29% acceptable
o
21% failure
o
7% resorption
Hydroxyl radicals diffuse through dentinal tubules breaking down periodontal tissue, causes
external cervical root resorption
Higher incidence of resorption when Superoxol used with heat
Superoxol = 30% HOOH
High diffusion through dentinal tubules
Place barrier directly on top of GP
Do NOT use heat
Do NOT use sodium perborate for superoxol