teeth WHITENING-Elgendy Flashcards
1
Q
Bleaching Rationale
A
- tooth discoloration due to intrinsice or extrinsic stains
- intrinsic stains
- aging
- excessive fluoride intake
- dental caires
- restorations
- extrinsic stains
- poor oral hygiene
- chromatogenic foods
- tobacco use
- intrinsic stains
- Cause of staining needs to be assessed to predict which bleaching will work better
- yellow staining responds well to bleaching
- blue-grey stain-difficult
2
Q
MOA: Hydrogen Peroxide vs Carbamide Peroxide
A
- Hydrogen Peroxide gel
- concentration varies: 3-40%
- releases all peroxide in first hour
- produces more sensitivty than carbamide peroxide
- Carbamide peroxide gell
- concentration: 10-22%
- 10%=orginal standard for at home bleaching
- penetrates enamel and dentin to pulp in 5-15 mins
- dissociates into urea and hydrogen peroxide
- urea-elevates the pH
- stablizes hydrogen peroxide
- urea-elevates the pH
- More stable molecule
- longer shelf life
- more predictable
- releases 50% of its peroxde in first 2-4 hours
- remainder released next 2-6 hours
3
Q
Types of bleaching
A
- Vital bleaching
- in-office bleaching
- at-home bleaching
- OTC bleaching
- Non-vital bleaching
- internal bleaching
- external bleaching
- walking bleaching
4
Q
In-Office bleaching
A
- 35% hydrogen peroxide
- applied directly on teeth
- may use light or heat to enhance peroxide release
- rapid and acceptable results
- tissue injury may occur
5
Q
At-home bleaching
A
- 10% carbimide in custom fit tray
- safe and excellent results
- less expensive than in-office
- requires longer periods of tx than in-office
6
Q
Internal Bleaching
A
- 30% hydrogen peroxide
- applied to pulp chamber
- heat applied for 30 mins
- solution rinsed from pulp
7
Q
Walking Bleaching
A
- Mixture of:
- hydrogen peroxide
- sodium perborate
- make a paste
- sealed in the pulp chamber for several days
8
Q
Non-vital power bleaching (internal)
A
- Hydrogen peroxide (30-35%) placed inn pulp chamber
- activated by light or heat
- gel removed
- tooth dried
- Walking bleach technique used between visits for 2 weeks
- Best technique bc of strong interaction b/w hydrogen peroxide and heat
9
Q
Inside/outside bleaching
A
- combo of:
- internal bleaching
- home bleaching
10
Q
Sodium perborate mixed with:
3-30% hydrogen peroxide vs distilled water
A
- No significant difference
- sodium perborate-Distilled water mixture took longer
- Shade stability is same
11
Q
Non-vital: Preliminary treatment
A
- determine cause of tooth discoloration
- take pre-treatment and post-treatment radiographs
- check quality of root filling
- root filling should be reduced 1-2mm below CEJ
- Clean cavity surface from debris and remnant of endo material
12
Q
non-vital tooth bleaching
A
- base required
- prevent radicular penetration of bleaching agents
- bleaching agent should be changed every 3-7 days
- successful bleaching apparent after 2-4 visits
- Use resin composites with lighter shades
- Negative influence of adhesion reduced by:
- beveling the cavity before acid etching
- pretreatment of enamel w/dehydrating agents (Alcohol)
- To dissolve peroxide remnants
- cavity cleaned w/sodium hypochlorite
13
Q
Teeth Whitening: Indications vs Contraindications
A
- Indications:
- dissatisfied w/tooth color
- matching teeth w/lighter indirect restoration
- whitening single discolored tooth
- Contraindications:
- Superficial stains
- Hypersensitive teeth
- carious teeth
- cracked teeth
- large pulp chambers
- severe enamel loss
14
Q
What percent of patients experience sensitivity during or after bleaching treatment?
A
25-70%
15
Q
Tooth Sensitivity Management
A
- Passive Treatment
- Active Treatment
- apply medicine using same bleaching tray
- fluoride
- potassium nitrate
- “numbness”
- apply medicine using same bleaching tray
- Passive treatment
- shorten duration of treatment
- stop treatment for day or more
- allows recovery
