Bleaching

1. BLEACHING

2.  INTRODUCTION
 CLASSIFICATION OF STAINS
 ETIOLOGY
 DISCOLORATION
 CHEMISTRY
 MECHANISM
 FACTORS AFFECTING BLEACHING
 BLEACHING MATERIALS
 CLASSIFICATION OF BLEACHING
INDEX

3.  VITAL BLEACHING
 NON VITAL BLEACHING
 TETRACYCLINE AND FLUOROSIS STAINS
 NEWER PRODUCTS
 CONCLUSION
 REFERENCES

4.  People with whiter smiles are generally perceived as more
attractive and beautiful. And, due to recent advances in
bleaching materials and techniques, tooth whitening or
bleaching is more popular than ever. It is currently the 1st
most requested cosmetic procedure.
 Its non-invasive procedure & conserves dental hard tissues, an
alternative to crowning & veneering.
INTRODUCTION

6.  Primary teeth bluish white
 Permanent teeth grayish yellow, grayish white, or yellowish
white.
 Its determined by translucency and thickness of enamel,
thickness and colour of underlying dentin and colour of pulp.
 Alterations may be physiologic, or pathologic and endogenous
or exogenous in nature.
COLOUR OT TEETH

7. Extrinsic stains
 Plaque, chromogenic bacteria, surface protein denaturation
 Mouthwashes, e.g. chlorhexidine
 Beverages (tea, coffee, red wine, cola)
 Foods
Dietary precipitate
Illness
Antibiotics (erythromycin)
Iron supplements
CLASSIFICATION OF
STAINS

8. A newer classification based on chemistry was put forth by
Nathoo in 1997
 N1 type or direct dental stains: chromogen bind to tooth
surface and causes discolouration
 N2 type or direct dental stains: chromogen changes colour
after binding to tooth surface
 N3 type or indirect dental stains: colorless material or
prechromagen binds to tooth and undergoes chemical reaction
to cause stain.

9. Intrinsic stains
Pre-eruptive
 Disease:
Hematological diseases
Liver diseases
Diseases of enamel & dentine
 Medication:
Tetracycline stains
Other antibiotics use
Fluorosis stains

10. Post-eruptive
 Trauma
 Primary & secondary caries
 Dental restorative materials
 Aging
 Smoking
 Chemicals
 Minocycline

11.  Decomposition of pulp
 Trauma
 Calcific metamorphosis
 Filling materials
 Aging
 Developmental defects
 Fluorosis
 Tetracycline
ETIOLOGY

12.  Most common cause.
 It goes unnoticed till few months after death of pulp or
treatment of tooth, because of slow formation of color
producing compounds.
 Intensity of discoloration = duration of time pulp was
necrotic.
DECOMPOSITION OF PULP

13.  Trauma leads to rupture of vessels  diffusion of blood into
dentinal tubules.
 Immediately  dark pink
 After some time  pinkish brown
TRAUMA

14.  Breakdown of erythrocytes occur, which result into
breakdown of hemoglobin into chromatic compounds such as
hemin, hematin, hematodin, hematoporphyrin and
hemosiderin.
 Sometimes hydrogen sulfide produced by bacteria combine
with hemoglobin to darken tooth.

15.  Tooth appears opaque due to loss of translucency
 After traumatic injuries, there might be disruption of blood
supply causing destruction of odontoblasts which are replaced
by undifferentiated mesenchymal cells that forms tertiary
dentin.
CALCIFIC METAMORPHOSIS

16.  Amalgam stain occur when
dentinal wall is thin and it
shimmers through enamel.
 Silver amalgam  slate gray
to dark gray
 Copper amalgam  bluish
black to black
FILLING MATERIALS

17.  Composite cause dark discoloration of margins and may stain
dentin
 Metal post can be visible through translucent enamel or release
metal ions.

18.  Physiologic deposition of secondary dentin affects the light
transmitting properties of teeth resulting in more opaque hue.
AGING

19.  Defects such as amelogenesis imperfecta, dentinogenesis
imperfecta, and enamel hypoplasia.
DENTINOGENESIS IMPERFECTA
DEVELOPMENTALLY DEFECTIVE
ENAMEL AND DENTIN

20. AMELOGENESIS IMPERFECTA

21.  Excessive fluoride uptake within the developing enamel layers.
 Appears as white or brown patches of irregular shape & form.
 The acquisition of stain is post-eruptive—surface is porous—
absorb the colored chemicals (Rotstein 1998).
 The severity & degree of staining = amount of fluoride
ingested during odontogenesis.
FLUOROSIS

23.  A broad-spectrum bacteriostatic antibiotic.
 Its administration during odontogenesis causes unsightly
discoloration of both primary & secondary dentitions.
TETRACYCLINE

24.  Staining effect - chelation of tetracycline molecules with Ca
ions in hydroxyapatite , primarily in dentine (Swift 1998). The
chelated molecules arrives at the mineralizing predentine-
dentine junction via the terminal capillaries of the dental pulp
(Patel et al 1998).
 The brown discoloration is due to photo-oxidation.

25. Drug
 Chlortetracycline (Aureomycin)
 Demethylchlortetracycline
(Ledermycin)
 Oxytetracycline (Terramycin)
 Tetracycline (Achromycin)
 Doxycycline
 Minocycline
Color stain on teeth
Grey-brown
Yellow
Yellow
Yellow
No reported changes
Black

26.  Chlorhexidine: mouthwash with it causes superficial black &
brown staining of teeth. Staining is enhanced in presence of
tea or coffee.
 Metals: copper, nickel & iron. The combination of plaque
occurring around metallic orthodontic brackets can cause
green line staining.
CHEMICALS

27.  This results when there is excessive irregular dentine in the
pulp chamber & canal walls.
 There may be a temporary disruption in blood supply followed
by disruption of odontoblasts.
 Irregular dentine is laid down in the walls of the pulp chamber.
 There is a gradual decrease in translucency of the teeth which
results in yellowish or yellowish-brown discoloration.
DENTIN HYPERCALCIFICATION

28. HOW???
HOW??
DISCOLORATION

30.  Oxidation/reduction reaction that takes place with bleaching is
known as REDOX reaction.
 Hydrogen peroxide (oxidizing agent) release free radicals with
unpaired electrons, thereby becoming reduced.
 Discoloured molecules in matrix accepts this unpaired
electrons and become oxidised, with reduction in
discolouration.
CHEMISTRY

31.  Principle: Oxidizing agent reaches the sites within enamel and
dentin to allow a chemical reaction to occur between the
discoloured segment and active ingredient.
 Bleaching is a slow transformation of organic substance
into chemical intermediates lighter in color than original.
 HYDRGOEN PEROXIDE has low molecular weight so it can
diffuse through enamel matrix. Agent opens the pigmented
carbon ring and convert them to carbon chains.
MECHANISM

32.  Carbon double bonds are converted into hydroxyl group,
amount of light absorbed in reduced.
 Hence tooth appears light in colour.

34.  As bleaching proceeds, a point is
reached at which only hydrophilic
structure exist. This is the material’s
SATURATION POINT.
 If bleaching process is allowed to
continue, it begins to breakdown the
carbon backbone of proteins. Loss of
enamel becomes rapid, with remaining
material being converted to CO2 &
water.
SATURATION POINT

35. Importance of saturation point
 The dentist should know that bleaching must be stopped at or
before the saturation point, since the price of material loss
(tooth brittleness & increased porosity) would then be greater
than any marginal gain in tooth whitening.
 Optimal bleaching achieves maximum whitening, while over
bleaching degrades tooth enamel without further whitening.

36.  Surface cleanliness
 Concentration of peroxide
 Shelf life
 Temperature
 pH
 Time
 Sealed environment
 Additives
FACTORS

37. HYDROGEN PEROXIDE
 Empirical formula H2O2
 Structural formula is HO-OH
 Molecular weight 34
 Concentration – 5 to 35%
 Clear, colorless, odorless liquid stored in light proof amber
bottles.
 Its unstable and kept away from heat, which could cause it to
explode.
MATERIALS

38.  It decomposes readily in open air in presence of organic
debris.
 Ischemic effect on skin and mucous membrane causes
chemical burn
 Amount of chemical used for bleaching is 1-2 ml

39. SODIUM PERBORATE
 Stable, water soluble, white powder, supplied in granular form.
 Based on oxygen content there are 3 types
Sodium perborate monohydrate
Trihydrate
Tetrahydrate

40.  Decomposes into sodium metaborate and hydrogen peroxide
releasing oxygen.
 When mixed with superoxol, it decomposes into sodium
metaborate, water and oxygen.

41. CARBAMIDE PEROXIDE (UREA HYDROGEN
PEROXIDE)
 Empirical formula is CO(NH2)2H2O2
 Molecular weight is 94.1
 Concentration ranges from 3 to 45% depending on at home
and in office bleaching.
 Commercial solution have concentration of 10% which
breakdown into urea, ammonia, carbon dioxide and 3.5%
H2N
H2N
C
O
HO-OH

42. BLEACHING
INTRACORONAL
AT HOME
(WALKING
BLEACH)
IN OFFICE
THERMOCATAL
YTIC BLEACH
EXTRACORONAL
IN OFFICE
VITAL BLEACH
AT HOME VITAL
BLEACH
CLASSIFICATION

43. Indications:
 Discoloration of pulp chamber
 Dentin discolouration
 Discolouration not amenable to extra coronal bleaching
AT-HOME OR WALKING BLEACH

44. Contraindications:
 Superficial enamel discolouration
 Defective enamel formation
 Severe dentin loss
 Presence of caries
 Discoloured composites

45. METHOD:
 Prepare tooth for bleaching by polishing the enamel surface.
 Apply petroleum jelly to gingival tissues for protection against
irritation.
 Adapt rubber dam.
 Re-establish access cavity

46.  Remove gutta percha filling that extends in pulp chamber with
hot finger plugger or gates glidden drill. It should be vertically
condensed 1 mm apical to cementoenamel junction.

47.  Using a small round bur in slow speed contra angle hand piece
remove residual debris or stains from pulp horns and along
incisal edge

48.  Seal the orifice of canal with 1 mm intracoronal barrier over
gutta percha. Glass ionomer cement, resin modified glass
ionomer cement, cavit or mineral trioxide aggregate can be
used as barrier materials.
 Level of barrier material should be 1 mm above the
cementoenamel junction so that agents are confined to the
crown portion above level of crestal bone.

49. Access cavity after placement of barrier

50.  Sodium perborate powder with distilled water is mixed in
dapen dish. 3% hydrogen peroxide can be used as thick paste
in severe cases.
 Place it with amalgam carrier.

51.  Place cotton pellet, slightly moistened with hydrogen peroxide,
over bleaching paste.
 Seal access cavity by 3 mm thick adhesive material to avoid
leakage of solution in the cavity.

53.  Effect is achieved 24 hours after treatment.
 Follow up 3-7 days
 If results are achieved no need of second appointment within
same week.

55.  A mixture of sodium perborate and distilled water was
mentioned in a congress report by Marsh and published by
Salvas
 The mixture of sodium perborate and water was reconsidered
by Spasser and modified by Nutting and Poe, who advocated
the use of 30% hydrogen peroxide instead of water to improve
the bleaching effectiveness of the mixture. A mixture of
sodium perborate and water or hydrogen peroxide continues to
be used today

56.  Place loose cotton mat saturated with 30% to 35% H2O2
(superoxol) on labial surface and in the pulp chamber.
 Its activated by exposing it to light and heat from powerful
light source.
 Tooth is subjected to several, usually 5-7 per minute exposure
and replenish H2O2 every 5 minutes.
 On completion, pellet of hydrogen peroxide and sodium
perborate is sealed in chamber.
IN-OFFICE OR
THERMOCATALYTIC BLEACH

57.  Heat activated superoxol is indicated for increased bleaching
effect.
 Care should be taken for overheating of teeth, periodontal
ligament, and gingival tissues.
 Cooling breaks are recommended.
 Additional thermal insulators such as vaseline, cocoa butter, or
orabase should be used.
 Increased risk of CERVICAL RESORPTION, hence walking
bleach is indicated.

58.  Ultraviolet light is used to activate from the labial surface of
tooth to be bleached.
 Time duration for UV light exposure: 2 minutes.
ULTRAVIOLET PHOTO
OXIDATION

59. Before application of the bleaching agent, the enamel margins of
the cavity should be etched with 37% orthophosphoric acid to
accomplish an adhesive temporary filling. The walking bleach
technique requires a sound seal around the access cavity with a
resin composite or compomer to ensure its effectiveness and to
avoid leakage of the bleaching agent into the oral cavity. In
addition, a good seal prevents recontamination of the dentin with
microorganisms and reduces the risk of renewed staining..
TEMPORARY FILLING

60. It is often difficult to place filling materials on a soft bleaching
agent. A small sterile cotton pellet impregnated with a dentin
bonding agent, placed on the bleaching agent and then lightcured,
simplifies the placement of a filling material. The temporary
filling should only be attached to the enamel margins of the
access cavity. During this phase of the treatment, the pulp
chamber is filled with the bleaching agent and not with an
adhesively attached restorative material, so that no internal
stabilization of the tooth is provided. Therefore, the patient
should be informed about an increased risk of fracture

61.  A good permanent restoration is the foundation of long term
success.
 Acid-etched and bonded composite resin are most favourable
restorative material.
 Restoration must be at a height that provides adequate seal as
well as incisal support.
 Problem exists, because of the remnants of peroxide or free
oxygen that inhibit resin polymerization (adhesive bond
strength between glass ionomer cements and composite resin
to enamel and dentin).
PERMANENT RESTORATION

62.  Dehydrating agents such as 80% alcohol, acetone containing
adhesives, application of sodium hypochlorite to dissolve
remnants, catalases, sodium ascorbate, alpha tocopherol.
 Atleast 1 week contact with aqueous solution is recommended
before bonding.
 Optimal bonding to bleached dentin and enamel was finally
established to 3 weeks after various studies.
 Light curing of composite should be from labial surface so
that shrinkage towards axial walls can reduce microleakage.

63. EXTERNAL ROOT RESORPTION
 Due to diffusion of hydrogen peroxide through unprotected
dentinal tubules leading to external cervical resorption.
 H2O2 can cause necrosis of cementum and periodontium
which results in inflammation and subsequent resorption.
 Worsen with light and heat activators.
ADVERSE EFFECTS

64. Left side radiograph was taken immediate after bleaching.
Right side radiograph was taken after 2 years

65. CHEMICAL BURNS
 Superoxol is caustic and causes sloughing of gingival tissues.
 Gingiva must be protected with petroleum jelly, orabase or
cocoa butter.
INHIBITION OF RESIN POLYMERIZATION
 Residual oxygen affects bonding and polymerization.
 Sodium ascorbate, buffered from vitamin C consists of 90%
ascorbic acid bound to 10% sodium- antioxidant.

66. INDICATIONS:
 Mild fluorosis, and tetracycline stains
 In order to match the existing color of crown lighter than normal
tooth.
CONTRINDICATIONS:
 Superficial stains
 Carious tooth
 Hypersensitive tooth
 Large pulp chamber
 Pregnant woman
 Exposed root surface
IN-OFFICE OR CHAIR
SIDE VITAL BLEACHING

67. METHOD:
 Evaluate tooth colour through shade guide.
 Clean enamel with pumice and water.

68.  Apply rubber dam or gingival liquid dam and vaseline or
orabase over gingiva.

69.  Apply 30-35% hydrogen peroxide liquid on labial surface of
teeth using cotton pellet or gauze (gel can be used instead of
liquid).
 Apply heat with heating device (System B, Kerr dental; Touch
n heat, Sybron Endo) between 125-140 F (52-60 C) or a light
source.

70.  Treatment time: less than 30 minutes.
 Pumice is used to remove residual gel.
 Irrigate and then polish with composite polishing cup.
 Apply sodium fluoride gel for 3-5 minutes and use fluoride gel
rinse for 2 weeks daily.
 Permanent restorations after 10 days.

73.  Application of hydrogen peroxide GEL concentration of 25%
- 38%
 Incase we use it as liquid then high concentrations are
associated with higher complications. They are not
thermodynamically stable so they might explode if not stored
in dark bottles in refrigerator. Excess gauze should be placed
in proximity of teeth that acts as reservoir.

74.  Light sources used for bleaching include conventional
ultraviolet light, tungsten-halogen and Xe-halogen, plasma arc,
or laser lights.
 In 1980’s Fuji Hilite dual cure material containing 35%
hydrogen peroxide. When the paste was mixed, it had green
colour that would give white colour upon activation. This was
time consuming and less comfortable for patient.

75.  Tungsten-halogen light provide heat and activate chemical
reactions. Application time was 30 to 60 seconds per
application per tooth, which was time consuming too as it
required atleast 3 passes.
 Premixed 35% hydrogen peroxide with carotene was made
available that converts light energy into heat that causes
increased breakdown into free radicals.
 LED lamps emit cold blue light of 465 nm can be used for 15-
20 minutes.

76.  Mix power bleach gel and apply on labial surface of teeth in 2-
3 mm thickness with brush.
 Individual tooth should be exposed for 3-10 seconds with
xenon plasma arc curing light or lasers..
POWER BLEACHING

77. XENON PLASMA ARC LAMP
 Principle: Thermal activation and activation of chemical
catalysts.
 It emits light of high intensity that produces heat energy so its
application is limited to 3 seconds interval for 3 passes.
 They emit blue light of short wavelength 380-500 nm.

78. LASERS
 Used for tooth bleaching at 830nm and 980 nm in
combination with 30% to 35% hydrogen peroxide gels.
 Application of 1 to 2 W of laser energy for 30 seconds per
tooth.

79.  Gel must stay on tooth for next 3-5 minutes and then remove
with wet gauze.
 Irrigate with water and then polish it with pumice.
 Apply neutral pH sodium fluoride gel.
 Patient should be informed about sensitivity for next 2-3 days
and refrain from intake of tobacco, red wine, tea, coffee, cola
for 2 weeks.

80.  Light increases the risk of tooth sensitivity during in-office
bleaching, and light may not improve the bleaching effect
when high concentrations of hydrogen peroxide (25–35%) are
employed. Therefore, dentists should use the light-activated
system with great caution or avoid its use altogether. Further
rigorous studies are, however, needed to explore the
advantages of this light-activated system when lower
concentrations of hydrogen peroxide (15–20%) are used.

81. POWER BLEACH USING
HEAT
 Heat up bleach by using one of two methods: immerse the
bleaching material in water bath at 80C; or boil bleach in a
crucible over flame or with hot air. It should be heated until it
starts bubbling
 Place bleach on tooth for 2 minutes.
 Remove it with gauze piece and don’t use water spray as it will
cool down tooth.

82.  Apply 3-4 times for 2-3 minutes each for 20 minutes.
 Patients can continue to do the at-home bleaching procedure
using 10% carbamide peroxide at home for 1 hour per day for
7 days.

83.  Easy to perform and less expensive.
 Uses: custom fit tray with 10% carbamide peroxide (because
shelf life of carbamide is more than hydrogen peroxide).
INDICATIONS:
 Superficial enamel discolorations
 Mild yellow discolorations
 Brown fluorosis discolorations
 Age related discolorations
VITAL TEETH BLEACH
AT HOME

84. CONTRAINDICATIONS:
 Severe enamel loss
 Hypersensitive teeth
 Bruxism
 Caries
 Defective coronal restorations
 Allergy to bleaching gels

85. TRAY FABRICATION:
 Upper and lower alginate impressions are taken. Casts are
poured and trimmed to 0.5 inch thickness base.

86.  Reservoirs (formed using pattern forming wax to a thickness
of 0.5-1 mm) are placed on labial surface that provide space
for bleaching agent.
 It should terminate 1mm above free gingiva.

87.  Duplicate the cast as wax will melt in vacuum forming
machine.

88.  Material used for fabrication of tray should be thick, semi rigid
plastic material.
 Cast is then placed in vacuum forming machine which involves
heat softening of tray and vacuum molding.
 Excess margins are then trimmed.

89.  If material is viscous then margins has to be scalloped,
terminating just incisal to free gingiva.
 If material is non viscous then margins has to be non
scalloped and extending on to gingival tissues.

90. Scalloped tray
TYPES OF TRAY

91. Straight line tray

92. Single tooth tray

93. INSTRUCTIONS TO PATIENT:
 Sufficient bleaching agent should be placed on labial surface and
excess should be removed.
 Wear tray for 4 hours every session, usually it is worn overnight.
 Remove tray from second molar region in peeling motion. It avoids
soft tissue injury.
 Tray should be washed properly and stored in cool or room
temperature.
 Results can be seen as early 2-14 days or may take as long as 6-12
months.

94. Both hydrogen peroxide and carbamide peroxide are used as an
active ingredient for professional at-home bleach.
3-7.5% H2O2 or 10-22% carbamide peroxide, especially those
with 10% carbamide peroxide are becoming more popular.

95. INSIDE/OUTSIDE
BLEACHING

98. TOOTH SENSITIVITY:
 Directly related to concentration of hydrogen peroxide.
 Due to permeation of bleaching agent into tooth structure
through enamel micro cracks resulting in pulpal hypermia.
 Post operative care should be taken with fluoridated mouth
rinse or amorphous calcium phosphate (ACP-CPP) is used to
promote remineralization.
ADVERSE EFFECTS

99. ENAMEL DAMAGE:
 Results in erosive areas and increased porosity.
 Reduction in enamel micro hardness.
 Changes organic-inorganic ratio which makes enamel weak.
GINGIVAL IRRITATION:
 When ill fitted trays are used, margins causes gingival irritation.
 Highly caustic agent causes sloughing of gingiva.

100. BLEACHING STRIPS:
 Whitening strip system with 6.5% w/v hydrogen peroxide.
 30 minutes twice daily for 21 days.
PAINT ON GEL:
 Painted directly on labial surface.
 Contains 18% carbamide peroxide which releases 6% hydrogen
peroxide.
OVER THE COUNTER
PRODUCTS

101. INDICATIONS:
 Developmental intrinsic stains
 Superficial enamel stains
 Yellow brown stains
 Superficial hypoplastic stains
 Enamel fluorosis
 White patches and spots
 Decalcification lesions
MICROABRASION
TECHNIQUE

102. CONTRAINDICATIONS:
 Age related staining
 Tetracycline stains
 Deep enamel hypoplastic lesion
 Deep enamel and dentin stains
 Carious lesion underlying decalcification

103.  Basic meaning of this is removal of enamel and it can be
achieved by fine multifluted tungsten carbide bur held in a
high speed hand piece operated with feather light touch.

104.  Night guard bleaching is the treatment of choice for fluorosis
with 10% carbamide peroxide
 Bleaching of mild fluoride stains occurs in 2-3 weeks whereas
moderate in 4-6 weeks

107.  Used for fluorotic teeth.
 In 1916 McCloskey reported that Kane successfully removed
fluorosis stains by applying heat and acid.
 In 1960’s McInnes used mixture of
Five parts of 36% hydrochloric acid, or HCl
Five parts of 30% hydrogen peroxide
One part of ether

108. METHOD:
 McInnes Solution
1 part of ETHER (0.2 ml)
5 parts of HYDROCHLORIC ACID (1 ml)
5 parts of HYDROGEN PEROXIDE (1 ml)
 Modified McInnes solution
20% sodium hydroxide instead of 18% hydrochloric acid as
its highly alkaline and dissolves calcium of tooth at slower
rate.

109.  Prepare mixture in a clean dapen
dish
 Apply it on tooth and gently
abrade surface with pumice in
rubber cup on slow speed contra
angle handpiece.
 Its neutralized with baking soda
and washed with water.
 Repeated 2-3 times for required
result.

111. CLASSIFICATION:
 First degree: Light yellow to light gray stains without banding.
 Second degree: Darker and more extensive yellow or gray
stains without bands.
 Third degree: Severe staining with dark gray or blue
discoloration with banding.
TETRACYCLINE STAINS

112. FOUR WAYS:
 Night guard bleaching with 10% carbamide peroxide over 6
months period.
 30% hydrogen peroxide and a thermostatically controlled heat
source. Discolours superficial stains and not stained dentin.
 Internal bleaching technique followed by intentional root canal
treatment.
 Instead of intentional root canal treatment, labial veneers with
composite resin or even porcelain veneer full crown
restoration are indicated.

115. BriteSmile To Go Whitening Pen
 The BriteSmile To Go Whitening Pen is easy to hold and easy to
travel with. You can keep this pen in your purse, at the office, in the
car, and travel bag. The pen applicator is very easy to use, a few
simple twists on the pen and the whitening formula forms on the
pen. You simply paint your teeth with the soft bristles on the
pen. The best part about the whitening process is that there
was no waiting period! You simply brush and rinse. The
BriteSmile To Go Whitening Pen lasts for 30 uses and you can
consistently keep your teeth white! I experienced no sensitivity and
saw immediate results the next day.
NEWER PRODUCTS

118. Opalescence® Xtra® Boost™
Professional results—in about an hour.
For a brighter, whiter smile without the wait, choose Opalescence Boost, an
in-office, chemically activated whitening treatment that offers results in
less than an hour. It's ideal for people who want instant whitening
gratification or those who have that special event coming up that requires a
bright, white smile.

120. Bleaching treatments have been a topic of interest for dentists
and patients alike for over 100 years. The dentist must evaluate
each patient carefully to determine the source of the staining in
order to determine the best treatment option. The dentist must
also make sure the patient is educated about the outcome of
treatment, so unrealistic expectations are identified and corrected
upfront.
Overall, bleaching is a very safe and satisfying experience for
patients. With proper treatment planning and patient education,
bleaching can be an important esthetic adjunct to any dentist’s
office.
CONCLUSION

121.  Endodontics, Ingle, 5th Edition
 Pathways Of The Pulp, Cohen, 8th Edition
 Endodontic practice, Grossman, 11th edition
 Complete Dental Bleaching, Ronald Goldstein
 Dental bleaching, Martin Kelleher
 Bleaching Techniques In Restorative Dentistry, Linda Greenwall
 Tooth whitening techniques, 2nd edition, Linda Greenwall
 The effects of light on bleaching and tooth sensitivity during in-office
vital bleaching: A systematic review and meta-analysis; JOURNAL OF
DENTISTRY; 2012
 Nonvital Tooth Bleaching: A Review of the Literature and Clinical
Procedures; JOE; 2008
REFERNCES