Bleaching
History
ROMANS Polished teeth using urea (carbamide) from
Portugal
MIDDLE AGES Barbaric bleaching
Filed teeth with an iron grater Used Aqua fortis (contains nitric acid)
WESTLAKE (1895) Bleached teeth with high concentrations of
hydrogen peroxide (H202) mixed with ether Treatment method was first published in the
American Journal of Dental Science
ABBOT (1918) Used Superoxol (30% (H202) to bleach teeth
discolored by fluorosis
AMES (1937) Bleached teeth with 30% hydrogen peroxide (H202)
and ether along with a source heat Treatment lasted approximately 30 minutes and
sessions were repeated up to 25 times.
ZACK AND COHEN (1965) First to conduct a scientific evaluation on how the
effect of the source of the heat affected the pulpo RESULT: No pulp damage found
Later confirmed by NYBORG & BRANNSTROM (1970)
ARENS (1972) Tried to bleach tetracycline discolorations with
35% Superoxol at 10°c below the pain threshold
History: Home Bleaching
KLUSMIER (1895) Orthodontist from Fort Smith, Arkansas Examined the effect of Gly-Oxid (Marion) used by his young
patients for removable appliances Discovered teeth became brighter and lighter tetracycline
stain disappeared
WAGNER Periodontist, Colleague of Klusmier Used the method in adults Result: gingiva less inflamed and teeth appeared whiter
MUNRO (1968) Side effect of Carbamide peroxide in a splint: Teeth
became whiter
HAYWOOD (1988) Adopted the concept
HAYWOOD AND HEYMANN (1989) Developed a home bleaching technique (currently the
used standard of care)
HAYWOOD (1990) Bleached teeth with high concentrations of
hydrogen peroxide (H202) mixed with ether Treatment method was first published in the
American Journal of Dental Science
ABBOT (1918) Used Superoxol (30% (H202) to bleach teeth
discolored by fluorosis
COMMERCIAL PRODUCTS INTRODUCED TO THE MARKET:
1989 White & Brite by Omni Based on Munro’s findings First commercial bleaching agent for vital teeth Contains 10% carbamide peroxide
1991 Opalescence by Den-Mat 1992 Nite White by Discus Dental 1994 Platinum by Colgate
Scientific Studies
HAYWOOD (1990) Studied on extracted teeth which were bleached for 5 weeks Scanning electron microscope showed no changes Bleaching materials used did not affect the topography of the
enamel
YARBOROUGH (1991) Published a review on the effectiveness and safety of
bleaching 2 effective ways: Carbamide peroxide and Hydrogen peroxide Hydrogen peroxide 3 to 6 times faster than Carbamide
peroxide
MURCHISON (1992) Examined the effect of carbamide peroxide on
enamel Conclusion: short term application did not cause
any significant change to enamel
Generally, majority show that it is safe to bleach teeth with
10% carbamide peroxide
Side Effects of Bleaching Agent
1. CONTAINS PEROXIDES Enhances effects of other chemicals (ex. Cigarette
smoke) Tendency to change oral flora If done over a long time, C. Albicans can accumulate
and hypertrophy the papilla
2. POWER BLEACHING Changes the hard structure of the hard tooth structures Resulted in Pulpitis (on animals)
3. TEMPORARY HYPERSENSITIVITY Disappears in almost every case when bleaching is
interrupted Remineralize using toothpaste with fluoride
4. ETCHED GINGIVA Unprotected gingiva Damage is temporary and disappears after a few days
5. TOOTH HYPERSENSITIVITY Patients should not have their teeth bleached Higher risk for post-operative sensitivity
6. ROOT RESORPTION On non-vital teeth prepared internally Possible CROWN FRACTURE
7. REDUCED BONDING ABILITY Avoid bonding restorations directly after bleaching Allow 2 weeks to elapse before bonding restorations
8. NEED FOR SUPPLEMENTARY BLEACHING Bleaching will decrease in time due and resulting to
color changes (coffee, red wine, fruit juices, soda, etc) Done approximately 1 year after 1st bleaching
Review of Bleaching Methods
BLEACHING OF VITAL TEETH Chemicals are placed on enamel Also called External Bleaching Can only change enamel discoloraiton
BLEACHING OF NONVITAL TEETHChemicals placed in the pulp chamberAlso called Internal BleachingCoronal dentin is changed
IN – OFFICE BLEACHING Power Bleaching 33% H2O2 with light and heat Stronger chemicals used Enamel damage could occur For patients who want to achieve results very
quickly Mostly, 3 bleaching treatments required
HOME BLEACHINGAdvantages
Little time spent (dentist must have an assistant or hygienist with necessary qualifications)
Usually more affordable Patients can bleach
whenever they wish to No rubber dam required Takes longer = Safer
Disadvantages Patients must collaborate
actively- Not worn, no effect- Too much, hypersensitivity
Higher cost and longer treatment time (if patients prefer to have their bleaching by the dentist)
Longer time