Bleaching in Dentistry

1. In Dentistry
Dr.Athul Chnadra.M

2. contents
 Introduction
 Tooth discoloration
 A brief History of bleaching
 Chemistry of bleaching
 Diagnosis and treatment planning
 Bleaching techniques
 Combining the techniques
 Bleaching and the micro abrasion technique
 Bleaching with restorative dentistry
 Bleaching with direct composite restorations
 Safety issues
 Home bleaching instructions

3. Intoduction
 ‘Everyone wants a whiter teeth !’
 Does that mean we can provide treatment to every
patient?

4.  Esthetics is an important factor in patient’s
decision to undergo endodontic treatment.
 But the teeth can and do discolour sometimes
before or sometimes after endodontic
treatment,In spite of all precautions we take to
prevent it.
 When teeth discolour, BLEACHING should be
considered as a means of restoring the tooth
esthetics!

5. BLEACHING !
 Is defined as, the lightening of the colour of
tooth through the application of a chemical
agent to oxidize the organic pigmentation in
the tooth. (GROSSMAN)

6. Goal of bleaching
 To restore the normal colour to a tooth by
decolorizing the stain with a powerful
oxidizing agent known as bleaching agent.

7.  Teeth are polychromatic (LOUKA 1989)
 The color varies from the gingival, incisal
and cervical areas according to the
thickness of enamel and dentin.
 The normal color of the primary teeth is
bluish white.
 The permanent teeth is,
 grayish yellow.
 Greyish white
 Yellowish white

8.  The tooth colour is determined primarly by the
dentine and modified by :
• the translucency and thickness of the enamel,
• (enamel thickness is more at the occlusal/incisal
edge and thinner at the cervical third of the tooth.
Dayan et al 1983)
• the thickness and color of the underlying dentin,
• the color of the pulp.
 Any alteration in the color may be due to
physiologic or pathogenic and endogenous or
exogenous in nature.

9.  With age, the enamel becomes thinner
due to abrasion and erosion
 The dentin becomes thicker due to
secondary and reparative dentin
deposition, which produces color changes.
 Elderly persons usually have yellow or
grayish yellow teeth than younger
persons.

10. Before we commence a bleaching therapy
the essential question to the patient should
be to determine the aetiology of the
discoloration.

11. Tooth discoloration
 A very common problem
 Can Occur at any age.
 In both primary and secondary teeth.
 Different parts of the tooth can take up
different stains.
 The aetiology is multifactorial.

12.  Principal causes (Grossman) are:-
 decomposition of pulp tissue
 trauma
 excessive hemorrhage following pulp
extirpation
 calcific metamorphosis
 filling material
 endodontic materials (root canal
medicaments)
 aging
 Iatrogenic

13. decomposition of pulp tissue
 In decomposed necrotic pulp
 The intensity of discoloration is directly
related to the duration of time th epulp
has been necrotic.

14. trauma
 Trauma -> rupture of blood vessels in the
pulp -> diffusion into the dentinal
tubules.
 dark pinkish hue- Almost immediately
after the accident.
 It will turn pinkish brown after a few
days.
 The discoloration will persist even after
the pulp is extripated or if the pulp
recovers.

15.  When the pulp succumbs to trauma,
 Hemoglobin breaks down
 Form various colored coompunds like
HEMIN, HEMATIN, HEMATOPORPHYRIN,
HEMOSIDRIN.
 Hydrogen sulphide produced by bacteria
will combines with the haemoglobin to
darken the tooth.

16. Pulpal hemorrhage during
extripation
 Discoloration occurs if haemorrhage is
excessive during the pulp extirpation.
 If haemorrhage persists – it indicates
there is still vital pulp fragment
remaining inside.

 What to be done?
 Irrigate thoroughly to remove blood
elements from the dentinal tubules.

17. Calcific metamorphosis
 Condition characterized by rapid deposition of
hard tissue within the root canal.
 Usually in anteriors followed by trauma
 In certain traumatic injuries- transient
disruption of blood supply-cause destruction
of odontoblasts.
 They are replaced by cells of undifferentiated
mesenchymal cells that laydown teritiary
dentin.
 Thus the tooth becomes opaque due to loss of
translucency.

18. Dental Filling materials
 Silver amalgam stain from slate gray to dark
grey.
 Copper amalgam cause bluish black to black
stain.
 amalgam stains occur when the dentinal walls
are thin and the filling matrial almost shimmers
through the enamel.
 Old resin composite restoration cause dark
marginal discoloration of the dentin during
microleakage.
 Metal posts maybe seen through the enamel or
may release metallic ions.

19. Root canal medicaments
 Some stain the tooth directly and others
stain only on decomposing or combining
with some other agents from endodontic
treatment.
 Eg: essential oil from resinous substance
discolour tooth structure.

20. Aging
 Physiologic deposition of secondary dentin
affects the light transmitting properties
of teeth.
 Result- more opaque hue

21. Classification of tooth
discoloration. (aetiology based)
 DAYAN et al 1983
Intrinsic stains
Extrinsic stains
Pre-eruptive Post-eruptive
disease medication

22.  Abbott, 1997 (causes and colors)
Extrinsic
discoloration
Intrinsic
discoloration
Extrinsic & Intrinsic
discoloration
Genetic
systemic
Systemicmedications
during development
body byproducts
body pulp changes
Iatrogenic causes

24. Extrinsic stains
 They are found on the outer surface of teeth
 Usually of local origin.
 Thus can be easily removed by scaling or
polishing .
 The stains deposit on the tooth surface due to
attractive forces which are long range
interactions such as vander waals and
electrostatic forces
 Short range interactions such as hydrophobic
forces, hydrophobic interactions and by
hydrogen bonds.

25.  Plaque, chromogenetic bacteria, surface
protein denaturation.
 Mouthwashes, eg. Chlorexidine
 Beverages, eg,tea,coffee,red wine,cola.
 Foods. Curry, cooking oil, fried food,
colored food, berries,beetroot.
 Dietary precipitate
 Illness
 Antibiotics. erythromycin, amoxicillin
 Iron supplements.

26. Classification of Extrinsic stains
 Metallic & non metallic stains
this classification could not explain the
mechanism of stain and all metals do not
stain teeth.
Newer classification is based on chemistry of
staining-by Nathoo 1997.

27. Nathoo’s classification 1997
 N1 type or direct dental stain:
 The colored material bind to tooth surface
 Same color of both stain and the
chromogen
 N2 or direct dental stain:
 Chromogen changes color after binding to
the tooth.
 N3 or indirect dental stain:
 Colorless material or prechromogen binds
to the tooth to have a chemical reaction to
form stain.

28. Intrinsic stains
 Is due to the presence of chromogenic material
within enamel or dentin,incorporated either during
odontogenesis or after tooth eruption.
 It can be related to the periods of tooth
development. Eg, amelogenesis imperfect or
dentinogenesis imperfect.
 Or after tooth development. eg., pulp necrosis.
 Or even excess ingestion of flourides, tetracyclines
during odontogenesis.
 Or interaction of antibiotics eith hydroxyapaptite
crystals during mineralization.
 Intrinsic colors are determined by optical
properties of enamel and dentin.

29.  Stains from the developmental phase are
almost impossible to eliminate.
 Stains from the pulp necrosis can be
removed by BLEACHING!

30. History of bleaching

31.  Most attempts to bleach the tooth in the 19th
centuary were done on non vital tooth and the
materials used were highly dangerous and caustic.
 Then from the early 1860’s, chlorine produced
from a solution of calcium hydrochloride and
acetic acid was highly efficient for bleaching non
vital teeth.
 Commmercialy they called it the LABARRAQUE’S
SOLUTION, a liquid chloride of soda.

32.  By the late 1800s, several oxidizing agents were used directly used on
the organic parts of the vital teeth, such as,
 Aluminium chloride
 Pyrozone(ether peroxide)
 Hydrogen dioxide (hydrogen peroxide or perhydrol)
 Sodium peroxide
 Sodium hypophoshate
 Chloride of lime
 Potassium cyanide
 Reducing agent often used was sulphurous acid.
 Of these, considered the most effective was
 Pyrozone
 Superoxyl
 Sodium dioxide.

33.  Bleaching agents were divided based on
which stains they most effectively
removed.
 Iron stains were removed with oxalic
acid,
 Silver and copper stains removed with
chlorine
 Iodine stains removed with ammonia
 Cyanide of potassium also removes metal
stains but was an active poison.
 Amalgam restorations were the most
resistant to bleaching.

34.  The bleaching agent was applied to the outside
Buccal surface and was expected to penetrate
through the enamel.
 1958, PEARSON found that lack of pulp in the
non vital teeth as an advantage and place the
bleaching material directly into he pulp
chamber.
 SPAAER,1961, gave a mixture of sodium
perborate with water to be placed in pulp
chamber and leave it for a week in situ.
 This technique became popular as the “WALKNG
BLEACH”.

35.  NUTTING & POE, 1963,1967,modified this by
combining 30% hydrogen peroxide and sodium
perborate sealed into the pulp chamber for a week.
 The synergistic effect helped and this technique
was popularised as “COMBINATION WALKING
BLEACH”.
 1965,STEWART, placed an oxidizing chemical in the
pulp chamber applied a heated instrument either
directly into the pulp or on the Buccal surface of
the tooth.
 This was called “THERMOCATALYTIC TECHNIQUE”.
 Special heating lamps were also used.
 the problem with this technique was cervical
resorption due to high conc of H2O2 WITH HEAT.

36.  SETTEMBRINI et al (1997) AND CARILLO et
al (1998) came up with “INSIDE/OUTSIDE
TECHNIQUE”.
 Patient will apply the beaching agent
directly into the pulp chamber with a
syringe.
 Then bleaching tray custom made is
seated into the mouth.
 Bleaching thus occurs from both inside
and outside simultaneously.
 WALKING BLEACHING
 COMBINATION WALKING BLEACH
 THERMOCATALYTIC
 INSIDE/OUTSIDE TECHNIQUE
Intracoronal/
internal
bleaching

37.  A chance discovery in 1960s, a
10%cabamide peroxide was placed in a
custom fitted tray which was placed in
the mouth for several hours or overnight
and the teeth lightened in a few days,
week, months depending on the nature of
the stain.
 Dr.VAN HAYWOOD & DR.HARALD HEYMANN
published this as the NIGHTGAURD VITAL
BLEACHING.1989.
 This seemed to be safe, efficient and was
widely accepted in mainstream dentistry.

38.  In 1918, ABBOT introduced bleaching at
the dentist’s chairside with a high
intensity light.
 This was thus called “IN-OFFICE POWER
BLEACHING”.
 But the high temperature intolerance and
faster regression rate caused tooth
sensitivity.
 Now light units like HALOGEN CURING
LIGHT, PLASMA ARC OR XENON POWER ARC
which do not generate heat, activates the
bleach.

39. Bleaching materials

40.  The goal of bleaching procedures is the restoration of
normal color to the tooth by decolorizing the stain with
a powerful oxidizing agent known as bleaching agent.
 The most commonly employed bleaching agents are as
follows:
 A. Hydrogen peroxide
 B. Sodium perborate
 C. Carbamide peroxide
 D. Over-the-counter(OTC) agents

41.  constituents of the bleaching gels
 Carbamide peroxide
 H2O2 and sodium hydroxide
 Non-hydrogen peroxide containing
material, Sodium perborate.
 Thickening agent –CARBOPOL/POLYX
 UREA
 Vehicle- glycerine, dentrifice, glycol
 Surfactant and pigment dispersants
 Preservatives
 Flavouring
 Fluoride (reduces sensitivity)

42. Hydrogen peroxide
 Whitening agent in dentistry in a conc of 5-35%.
 Peroxides are
 InOrganic : if hydrogen atoms are substituted with metals
 Organic : if h2 atoms are substituted with organic radicals.
 They are strong oxidisers
 Low molecular weight.
 Clear
 Odourless
 Colorless liquid
 Stored in light proof amber bottles.
 Unstable and must be kept away from heat as it can explode.
 Decomposes in open air-thus store in sealed refrigerated containers.

43.  Can penetrate dentin
 Release oxygen
 These released O2 breaks down the
double bond of inorganic and organic
compounds inside the tubule.
 How to use?
 Dispense 1-2mL into a clean dappen
dish.
 Discard any remaining solution.
 H2O2 can be used alone or mixed with
sodium perborate into a paste (walking
bleach).
 3-7.5% H2O2 are used in home bleach.

44. Concentrations of h202

45.  Caution!
 Ischemic effect on skin and mucous
membrane causes chemical burn.
 Painful if it contacts the nailbed or soft
tissue under fingernails.

46. Sodium perborate
 Stable white powder
 Water soluble powder
 Supplied as granules
 Granules grouped into powder for usage.
 3 types based on oxygen content:
 Monohydrate
 Trihydrate
 Tetrahydrate
 Thus used in “WALKING BLEACH”.
Na PERborate + water = Na METAborate + H2O2+ O2
Na PERborate + SUPEROXOL = Na METAborate + H2O+ O2

47. Carbamide peroxide CH6N2O2
 UREA HYDROGEN PEROXIDE
 Conc. : 3- 45% depending on at-home or
in-office bleach.
 Commonly in home bleaching.
 10% is used in commercial preparations.
 10% carbamide peroxide decompose into
6.65% urea+ ammonia+ CO2+ 3.5%H2O2.
 15% CH6N2O2 => 5.4% H2O2
 20% => 7% H2O2
 35% solution => 10% H2O2

48.  Home bleaching
 – 5 percent carbamide peroxide
 – 10 percent carbamide peroxide
 – 15 percent carbamide peroxide
 – 20 percent carbamide peroxide.
 • In office bleaching
 – 35 percent solution or gel of carbamide peroxide.

49.  In addition flavouring agents and
glycerine, sodium stannate, phosphoric or
citric acid are added.
 Thickening agent : CARBOPOL- water
soluble polyacrylic acid polymer
 This prolongs the active peroxide release
 Thus more shelf life.

50. Thickening agents
 Carbopol (carboxypolymethylene ) is generally used.
 TROLAMINE, a neutraliser is often added to carbopol to
reduce the ph of the gel to 5-7.
 Solution with carbopol will release oxygen slowly and sustain
for 10hours.
 Maximal release occurs by 2-3 hours.
 Other solutions release O2 in less than an hour.
 The rate of oxygenation affects the frequency of solution
replacement during bleaching.
 Carbopol enhances the viscosity thus better retention of the
gel in the tray and to the tooth.
 Also Less material is thus required for the treatment. (29mL
per arch)
 The increased viscosity prevents the saliva from breaking
down the H2O2.

51.  POLYX is a thickener used in the colgate
platinum system.
 The composition of which is a trade
secret still.

52. Urea
 It stabilizes the H2O2 by giving a loose
association with it.
 Elevates the pH.
 Enhance anti cariogenic effects
 Enhance saliva stimulation
 Enhance wound healing properties.
 The effect of ph depends on the
concentration of the urea and duration of
its application.

53. Vehicle
 GLYCERINE: carbamyl peroxide with
glycerine base has enhanced viscosity and
ease of manipulation.
 Side effects :- dehydrates the tooth
Tooth loose the translucency
thus.
Sore throat in some patients
 DENTRIFICE: vehicle for Colgate platinum
system
 GLYCOL: this is anhydrous glycerine.

54. Surfactant & pigment
dispersants
 Wets the surface allowing H2O2 to diffuse
across the gel-tooth boundary.
 Pigment dispersant keep pigments in
suspension.
 These containing kits are more efficient
and has more active gel.
 Eg: Nu-Smile and Brite Smile.

55. Preservatives
 Citroxain, phosphoric acids, citric acid or
stannous stannate.
 They sequestrate transitional metals like
iron, Cu,Mg, thereby accelerating the
breakdown of H2O2.
 They give the gel more durability and
stability.
 They have a mildly acidic ph.

56. Flavourings
 Gives a choice of bleaching agent
 Improve patient acceptability of the
product.
 Eg: melon, banana, mint.

57. OVER-THE COUNTER(OTC)
BLEACHING AGENTS:
 These includes :
 Tray systems
 Trayless systems
 Chewing gums
 Toothpastes
 Bleaching strips and
 Paint- on products
 These products primarily work by
removing extrinsic surface stain only.

58. Over the counter kits (OTC)
 Acid rinse: usually citric acid/phosphoric
acid
 Bleaching gel: applied for 2 minutes have
acidic ph
 Post-bleach polishing cream : toothpaste
with titanium dioxide that gives a
temporary painted white effect.

59. Mechanism of bleaching

60.  Hydrogen peroxide has a low molecular
weight and enamel being semipermeable
membrane, diffuse the H2O2 through the
enamel matrix.
 The free radicals interact with organic
molecules to attain stability.
 Bleaching agent opens up the highly
pigmented carbon ring (yellow color) and
converts them to hydroxyl groups,thus the
amount of light absorbed is reduced.
 Thus the tooth appears more light in
color.
 if bleaching is continued beyond this
point then the tooth structure will be
weaken and will lead to its fracture.

61.  H2O2 is a oxygenator and an oxidant.
 The yellow pigment (XANTHOPTERIN) is oxideised
to the white pigments (LECOPTERIN)
 The hydrogen peroxide breaks down to water and
oxygen and a free radical HO2. perhydroxyl, which
is short lived but very reactive and a great
oxidative agent.
 It can break up a large macromolecular stain into
smaller stain molecules which get expelled to the
surface by diffusion.
 It can attach to the protein structure and protein
matrix.
 it can oxidise tooth discoloration.
 Carbamide peroxide, breaks down to water oxygen
urea CO2 and ammonia.

62. Factors affecting
bleaching

63.  SURFACE CLEANLINESS:
 CONCENTRATION OF PEROXIDE:
 SHELF LIFE:
 TEMPERATURE:
 PH:
 TIME:
 SEALED ENVIRONMENT:
 ADDITIVES:
 OTHER FACTORS:

64. Classification of bleaching

65. Non vital bleach
 Thermocatalytic / in-
office
 Walking bleach / out-of-
office / Home technique
 Inside/outside bleaching
 Closed
chamber/extracoronal
bleaching
Vital bleach
 ..
Laser bleach
 Power bleach / in-office
 Night guard / dentist
prescribed home
technique

66. 1)Intracoronal (for endodontically
treated/nonvital teeth)
At-home /walking bleach
in-office thermocatalytic bleach.
2) extracoronal bleaching (vital tooth)
in-office vital bleach.
At-home vital bleach.

67.  Thermocatalytic
35% /h2O2
liquid

68.  Walking bleach –spasser and nutting
Superoxol
(30% h2o2 by
volume)
Superoxol
+
Sodium perborate

69.  Power bleach
35% h2o2
Oxidation
heat

70.  Night guard
10-15%
carbamide
peroxide
3% h2o2 (active ingredient) +
7%ureaDegrades into

71. 1961 Spasser Walking
bleach
Sodium
perborate
+water in
pulp
chamber

72. Non vital bleaching

73. Walking bleach
 Less chairtime
 Safer
 Comfort for the patient

74. Indications
 Superficial enamel discolouration’
 Defective enamel formation.
 Severe dentin loss
 Discolored composites
 Presence of caries.
ContraIndications
 Discolored pulp chamber
 Discolored dentin
 Discolorations are not amenable to
extracoronal bleaching

75. How to do walking bleach?
 Preparation
 Always examine and evaluate the crown as it should be
intact.
 Crowns weakened by wide access cavities, large multiple
restorations and caries should be managed.
 Restore them with posts and core and a full veneer crown
for best funtional and esthetic result.
 Obturation should be checked radio graphically for voids and
adaptation.
 If the bleaching agent percolates through it, then it can lead
to acute apical periodontitis.
 If silver cones are used to obturate, substitute it with gutta-
percha cones.

76.  Method
 Polish the tooth with prophylaxis paste to clear the
surface.
 evaluate the shade guide and take clinical
radiographs at every step of the treatment to
appreciate the results.
 Apply petroleum jelly on the gingiva and around the
tooth for protection.
 Adapt rubber dam and clamp.
 Re-establish the access cavity.
 Remove any excess gutta percha in the pulp chamber
by hot finger plugger and condense it 1mm apical to
the CEJ.
 Use a periodontal probe to assure it by placing it in
the pulp chamber and reproducing the same in the
gingival sulcus.

77.  Use small round bur to remove any residual stains
or debris inside the chamber or on the pulp horn.
 Seal the orifice of the root canal with atleast 1mm
intracoronal barrier over the gutta-percha using
GIC,Cavit, MTA or resin GIC.
 MTA is shown to be superior.
 The level of the barrier should be 1mm incisal to
the CEJ so as to confine the bleaching agent only
to the crown above the level of the bone.
 Keeping it away from the cervical area can prevent
cervical resorption.
 Protect the patient face by draping it and give a
pair of glasses for the eyes.

78.  Plastic apron over the patients clothes.
 Operator must wear gloves.
 Mix sodium perborate + distl.water.
 Use 3% h2o2 to a thick paste in a
dappen dish for severe stains.
 Use amalgam carrier or plastic
instrument to carry this thick paste
into the pulp chamber and cover entire
facial surface with it.

79.  Place moistened cotton pellet with
h2o2 over this bleaching paste.
 Seal the cavity to 3mm thickness using
an adhesive material.
 If you use IRM then press it against the
cavity with gloved finger till it sets to
ensure it is not displaced with oxygen
release.

80.  After 24hours maximum results will be
obtained.
 Recall the patient after 3-7 days.
 If the shade is too dark,do additional
bleaching.
 If too light shade, permanently restore it.
 Bleached teeth with too light shade might
revert back shortly after bleaching.
 This could be due to the ingress of saliva
into the dentin through the enamel, whose
permeability could have increased by
bleaching.

81. Thermocatalytic /
In-office bleaching.

82.  Light Sources Used for In-office Bleach Various
available light sources are:
 • Conventional bleaching light
 • Tungstenhalogen curing light
 • Xenon plasma arc light
 • Argon and CO2 lasers
 • Diode laser light.

83.  Conventional Bleaching Light
 • Uses heat and light to activate
bleaching material
 • More heat is generated during
bleaching
 • Causes tooth dehydration
 • Uncomfortable for patient
 • Slower in action

84.  Tungsten-Halogen Curing Light
 • Uses light and heat to activate
bleaching solution
 • Application of light 40 to 60 seconds
per application per tooth
 • Time consuming

85.  Argon and CO2 Laser
 • Truelaser light stimulate the catalyst in
chemical so there is no thermal effect
 • Requires 10 seconds per application per tooth

86.  Diode Laser Light
 • Truelaser light produced from a
solid state source
 • Ultra fast
 • Requires 3 to 5 seconds to activate
bleaching agent.
 • No heat is generated during bleaching

87.  Xenon Plasma Arc Light
 • Highintensitylight, so more heat is
liberated during bleaching
 • Application requires 3 seconds per tooth
 Faster bleaching
 • Action is thermal and stimulates the
catalyst in chemicals
 • Greater potential for thermal trauma to
pulpand surrounding soft tissues.

88.  30-35b % H2O2 is placed in the pulp chamber
 Heat/ light or both are applied on it.
 Familiarize the patient with the expected
outcome and the possibility of future
rediscoloration.
 Analyse radiographically the endodontic
periodontic condition of the tooth.
 Assess and Replace defective restorations.
 Use a shade guide and take photographs.
 Apply a protective cream on gingival tissue and a
rubber dam.
 If a heat lamp is used then avoid metal clamps to
avoid discomfort.
 No anesthesia.
 Use Protective sunglasses for doctor and patient

89.  apply 2mm of sufficient thick layer of protective cement barrier
like polycarboxylate / ZnPO4 or GIC / IRM or even cavit over the
obturation.
 Soak a small cotton pellet in 30-35% H2O2 solution place in the pulp
chamber.
 A bleaching gel of H2O2 can also be used instead.
 Apply heat with a heating device or a light source.
 Keep the light at 2feet from the tooth.
 Temperature should be between 50-60’C
 Re-wet and replace the cotton pellet as necessary.
 The must be limited to 5minutes of separate periods than using it
continuously for long time.

90.  If too much sensitivity develops
discontinue the procedure.
 Remove the heat/light source and allow
the tooth to cool down every 5-6 minutes.
 Then wash with warm water for 1min.
 Remove the rubber dam.
 Dry the tooth

91.  Place walking bleach paste (h2o2+ sodium
perborate) in the pulp chamber.
 Recall the patient after 2weeks and check
the effectiveness.
 Compare with the pre-op photographs and
the same shade guide.
 If necessary repeat the therapy.

92.  A study invitro, compared the bleaching
with H2O2 and heat for 12 minutes to
pacj=king it with walking bleach paste for
7days or a combination of both the
techniques.
 NO significant difference was shown in
the results.
 The walking bleach consumes least time
and no special equipment is the method
of choice.

93. Intentional endodontics and
intracoronal bleaching
 In treating intrinsic tetracycline
discolorations.
 The tooth is endodontically treated
deliberately and intrinsic bleaching is
done.
 Only intact teeth without coronal defects
caries or restorations should be treated.

94. ADVERSE EFFECTS OF
INTRACORONAL BLEACHING
External root
resorption
• Diffusion of H2O2
through
unprotected
tubules will lead to
resorptive changes
in the
periodontium.
• Casustic effect
cause necrosis of
cementum and
periodontium
• Initiates
inflammation and
thus resorption.
Chemical burns
• Caustic to the
gingiva and soft
tissues
• Sloughing of gingiva
Damage restorations
• The residual oxygen
will interfere with
the polymerization
and bondig of the
composite resins.

95. How do I give a composite
restoration then?
 Assure complete removal of residual H2O2
in the pulp chamber.
 Inject CATALASE before bonding( ROSTEIN
1993)
 Removes the residual oxygen from the dentine.
 Sodium ascorbate- a buffered form of
Vit.C (90% ascorbic acid + 10% Na) can
also be used as anti oxidant.
 Give a GIC restoration immediately and
cut back space for composite after 2
weeks.

96. Suggestions for safer non
vital bleaching
Efficient isolation
Protect oral mucosa
Verify the quality of endodontic restoation
Use a intracoronal protective barrier
Avoid acid etching
Avoid strong oxidizers
Avoid heat
Recall periodically

97. Vital teeth Bleaching

98. Night guard/ home bleaching
1989
-haywood & heymann

99. Home bleaching 1989
-haywood & heymann
 A simple predictable technique
 98% success in non-tetracycline stained teeth and 86%
success in tetracycline stained.
 The dentist gives a custom tray + 10% carbamide
peroxide + a bleaching protocol.
 Patient has to wear the tray with the material for
several hours –day/night depending on his/her
schedule.
 Cheaper and popular.

100.  Also known as
 “NIGHTGAURD VITAL BLEACHING” –
since patients slept with the tray in
the mouth.
 Matrix bleaching
 dentist assisted/ prescribed home-
applied bleaching
 Dentist-supervised at-home bleaching
 At-home bleaching.
 Internal/External bleaching,
 modified walking bleach technique.

101. Indications (GREENWALL 1999)
 Mild generalised staining
 Yellowing with age
 Mild tetracycline stains
 Very mild fluorosis
 Acquired stains superficially
 Smoking and tobacco
 Absorbed or penetrated stains from tea/coffee
 Pulpal necrosis induced
 Patient who desires a minimal dental treatment
for a better color shift
 Young conscious patients with inherited grey or
yellow hue.

102. Contraindications (GREENWALL 1999)
 Severe tetracycline stain
 Severe pitting hypoplasia
 Severe fluorosis
 Adolecent patient with large pulp
 Unrealistic expectations about the results.
 Defective existing restorations
 Attrited,abraded,eroded tooth.
 Surface cracks, fractures.
 Large anterior restorations
 Periapical pathologies
 Non compliance patients (i.e. lack of co-operation)
 Pregnant or lactating (effects on fetus unknown)
 Smokers
 hypersensitivity

103.  Commonly used Solution for Night Guard Bleaching
 10 percent carbamide peroxidewithor without
carbopol
 • 15 percent carbamide peroxide
 • Hydrogen peroxide(1 to 10%).

104.  Treat sensitivity with flouride applications
or a bonding agent or a bonded
restoration prior to bleaching.
 Fractured teeth or maligned teeth can be
treated best with a porcelain veneer or
orthodontic treatment.

105.  this technique requires methodological
documentation and execution of:
 Dental & medical history
 Clinical examination
 Radiograph of the teeth to be treated.
 Impression of dental arches for the
construction of bleaching tray.
 Recall visits to assess the progress and
compliance.

106. Fabricating the vaccum
pressed tray
 Trim the base of the cast to 0.5 inch thickness
eliminating the vestibule,tongue and palatal
regions.
 Use a light polymerised resin as reservoir on the
labial surface to a thickness of 0.5-1mm for the
space for the bleaching agent to seat.
 Reservoir should terminate 1mm short of the free
gingival margin.
 Do a de-waxing before placing the cast in vaccum
forming machine, if wax is used to make reservoir.

107. Impression making for trays
 Alginate or elastomers can be used
 Make sure to eliminate air bubbles
 Pour the cast as soon as possible to avoid
distortions

108. Ideal tray properties
 Strong enough to defend damages during wear
 Should not distort during use or storage
 Bioinert material
 Non irritating
 Thin enough for comfort
 Smooth and well polished
 Should not impinge anywhere
 Comfortable fit not too tight
 No undercuts
 Freedom of movement for frenum attachments
 Good Retention
 Easy to clean and rinse

110.  pictures

111.  The viscosity of the bleaching
material determines the extent of
the tray.
 Scalloped margins for highly viscous,
ie, terminating incisal to the free
gingival margin.
 Nonscalloped if non viscous and must
extend on the gingival tissues.

112. Instructions to the patient
 Check the tray fit and comfort in the second visit.
 Patient must brush away any debris on teeth before using
the tray to enhance the effectiveness.
 The bleaching agent on the tray should cover the facial
surface of the teeth.
 Wipe away any excess bleaching agent from the gingiva.
 Wear it for min 4hours for every session.
 If no sensitivity then he can use it twice daily.
 Always remove the tray from the second molar first in a
peeling action to protect the soft tissues.
 Brush and rinse off the material from the tray after every
use.

113.  Store the bleaching agent in cool or warm
temperature.
 The results should be expected by 2-14days to
6-12 months.
 Patient should be well informed of the
treatment outcome.
 If the discoloration is uneven, the load the
tray in areas corresponding to that teeth
which require further bleaching.
 Cut the tray ain areas of ceramic crowns or
crowns to avoid etching and weakening of
ceramic.
 Regular checkup visits are mandatory.

114.  The occlusal pressure and salivary flow
dilute the gel.
 Thus the gel have to replenished every 1-
2hrs if the tray is worn in the day. (DUNN
1998)
 Overnight can eliminate this problem as
there will be reduced salivary flow and
reduced occlusal pressure.
 Thus for maximum benefit and
compliance wear overnight. (HAYWOOD
2000)

115. Further treatment
 Ask the patient to return the trays to
protect him from over bleaching with
obsession.
 Renew composite restorations If any after
two weeks.
 Preparation of anterior crowns or
porcelain veneer should be delayed by a
month.
 This is to avoid rebound shade shift

116. Adverse effects
reassure the patients that these are minor and
transient that it will disappear soon after completion
of treatment
 Tooth sensitivity
 Enamel damage
 Gingival irritation
 Mercury release from amalgam
restoration.
 Altered taste sensation.

117. Possible causes of sensitivity
and gingival irritation
 Adding carbol or other
thickenening agents
 Patients below 40yrs
 Anhydrous based whitening
products
 Carbamide peroxide byproducts
 Chemical interaction of tray
 Conc. Of the whitening solution.
 Dissolving media
 Exposure time
 Frequency of application
 Inherent patient sensitivity
 Medical status of the patient
 pH of the whitening solution
 Women more than men
 Tray rigidity and tray material.

118. Power bleaching

120. Combining bleaching
techniques

121. Why combine the bleaching
treatments?
 To make it more effective
 To motivate the patient to continue the
treatment at home.
 To treat a single discoloured vital/non
vital tooth.
 To sequence and stage bleaching in a
complex treatment plan.
 To treat difficult stains like ttracycline
 Treat stains of different origin on the
same tooth.

122. Inside-/ outside combination
bleaching technique

123. Inside-/ outside combination
bleaching technique
 Also called as
 Internal/ external bleaching (SETTEMBRINI,1997)
 Patient-admimistered intracoronal bleaching
 Modifies walking bleach (LIEBENBERG 1997)
 This is intracoronal bleaching + home bleach
 A more simpler method to bleach non vital teeth

124. Indication for inside/outside
bleach
 Adolescents with incomplete gingival
maturation
 Single dark non vital tooth with adjacent
teeth sufficiently light.

125.  Preparation of the barrier
 Gp is removed 2-3mm below CEJ for barrier
space.
 Use GIC or resin cement to build up the
barrier.
 Clean the access cavity
 Remove any remaing pulp horns.
 Etch to clean the internal surface
 Place a cotton pellet to avoid food impaction
 Shade assessment
 Record Pre-operative shade of the non vital
and the adjacent teeth.
Procedure

126.  Instructions for home bleaching
 Check for fit and comfort of tray
 Tel patient not to bite with the anterior teeth
during the treatment tenure
 Ask to remove the cotton pellet with a tooth
pick
 Apply the bleaching syringe directly in the
cavity before seating the tray.
 Remove the excess with a toothbrush or tissue
 Irrigate the cavity with water after bleaching.
 Keep a fresh cotton wool
 After every meal- irrigate again and replace
the cotton.

127.  Treatment timing
 The more often the solution is changed the
quicker the bleaching will occur.
 If patient can change the solution every 2
hours, then 5-8 applications is enough for
desired results
 Night application will be slower than twice
daily application
 Unless severely discoloured. Apply bleach
during day as then it can be better controlled.

128.  Reassessment of the shade and the results
 Recall after 3-7 days
 Terminate if desired results are achieved.
 Seal the access cavity
 Use temporary restoration
 Permannet restoration after 2weeks.
 If in a hurry-then first irrigate cavity NaOHCl then clean
using CATALASE.
The longer the tooth had been discoloured the
longer the treatment
the darker the shade the longer the duration

129.  Review
 Periodic review
 Annual radiographic review to check
for cervical inflammation

130. Benefits
 More area of penetration for both internal and external
bleach
 Lower conc. Of bleach (10% carbamide peroxide with
neutral pH)
 May eliminate side effects (cervical resorption). [not 100%
 The access cavity is left open,
 No need to change dressing
 Oxygen free to escape
 No build up pressure
 Duration is reduced to days
 Catalase can reduce the residual oxygen.
 No heat activation required.

131. Options to treat non vital teeth

132.  Intra + extracornal bleaching.
 Applied directly into the pulp chamber
and retained with home bleaching matrix.
 Inside/outside technique with beaching
tray, uses
 10% carbamide peroxide
 5% 16% 22% differing concentrations
 35% carbamide peroxide
open chamber bleaching

133.  Material is placed on the external surface
of the tooth.
 Other operations
 Power bleaching using 35% hydrogen peroxide
 Nightgaurd Vital Bleaching using 10% 15% 20%
applied only to the non vital tooth in the tray.
 Assisted bleaching applied to the external
surface on its own via a bleaching tray.
closed chamber bleaching-extracoronal

134. Combing power bleach +
home bleach

135.  One or two power bleach in-office bleach
sessions followed by home bleaching.
 GARBER advises patients to use matrix
system for only 30-45 minutes at night
instead of the longer times proposed for
conventional home bleach.
 Advises alternate days for the first week
 Then once per week till the desired
results.

136. benefits
 Eliminates the repeated sittings and
multiple rubber dam application
 Best results from combination
 The procedure can adapt to the lifestyle
and need of the patient
 Power bleach provides a jumpstart and
gives improvement while the tray is being
made

137. MICROABRASION &
BLEACHING

138. What is enamel
microabrasion?
 A microscopic layer of enamel is simultaneously
eroded and abraded with a special compound,
leaving a perfectly intact enamel surface
behind. (CROLL,1991)
 CROLL, called it “ ENAMEL DYSMINERALIZATION”
 Treating,
 Hypermineralization
 Hypomineralization
 Staining

139. Microabrasion VS bleaching
 Microabrasion improve the tooth color by
permanently eliminating the superficial
discoloured enamel.this is preffered when
general tooth colour changes are not needed
but a defined isolated surface discoloration is
present.
 Bleaching improves tooth colour by lightning,
whiteing and brightening teeth. But bleaching
preserves the intact fluoride rich layer of
enamel and tooth shape. The tooth may
rebound to slightly darker shade over the years
but never to their original darker shade.

140. Microabrasion + Bleaching
 The yellow or darker shade that may
appear after microabrasion can be
eliminated by bleaching.

141. Hydrochloride acid
 10% Hydrochloride acid + pumice are the main ingredients.
 Its use depends on the decalcification of enamel.
 should be selectively applied and well controlled.
 Normally less than 200micronmeter in total of enamel is
removed. maybe much less.
 Its effects are non-selective and superficial.
 Adding an abrasive like pumice can enhance the technique

142. Indication
 Developmental intrinsic stains
 Superficial enamel surface stains and opacities
 Yellow-brown areas
 Multicolored stain
 Superficial hypoplastic enamel /enamel
dysmineralization
 Enamel fluorosis
 White patches and spots
 decalcification leasions from plaque stasis and
orthodontic brackets
 Irregular surface textures

143. Contraindications
 Age-related staining
 Tetracycline stain
 Deeper enamel and dentin hypoploastic lesions
 Most amelogenesis imperfect
 Most dentinogenesis imperfect
 Carious lesions underlying decalcified regions.

144. Treatment Planning
 Saliva acts as a camouflage-hides the residual stains
left.
 thus the teeth should be in their usual moist state
before and after they are evaluated for microabrasion.
 So It is okay to not completely remove the stains.
 Discuss with the patient the side effects benefits and
further options such as bleaching, veneers, crowns etc.
 Never raise their expectations.
 In fact give a pessimistic prognosis thus you don’t end
up disappointing them.
 Assess the enamel from incisal edge for labiolingual
thickness of the tooth and enamel lesion.

145. How to micro abrade the
enamel?
 Clean the enamel with rubber cup and prophylaxis paste
 Isolate the teeth.
 Use Vaseline on lips
 Protect soft tissues
 Use a FINE GRIT DIAMOND/ TUNGSTEN CARBIDE BUR(CROLL
1997) to start on the lesion.
 Apply the microabrasion compound to th eareas of interest for
60s intervals with rinsing.
 Over duration of application can be harmful to both teeth and
soft tissues. (whitening or ulcerations)
 Wipe off first before the wash to prevent splashing.
 Check labiolingually that minimal enamel reduction is taking
place.

146.  Repeat the procedure
 Polish using fine grit fluoridated prophylaxis
paste.
 Rinse
 Remove the rubber dam
 Apply topical fluoride application to the teeth
for 4minutes.
 Re-evaluate the result. More than one visit.
 Review the patient 4-6 weeks later.

147. Advantages
 Easily performed
 Conservative treatment
 It is inexpensive
 Teeth require minimal subsequent
maintenance
 It is fast acting
 removes yellow-brown, white multi-
coloured stain
 It is effective
 Results are permanent

148. Disadvantages
 Removes enamel
 Hydrochloric acid componds are caustic
 Require protective apparatus for
patient,dentist and assistant
 Require a visit to the dental office
 It cannot be delegated and must be
carried out by dentist.

149. Microabrasion + home bleach
 After 6weeks of micro abrasion treatment make
trays instrusct the patient how to use bleach and
the trays.
 Home bleaching protocols are the same.
 Results are encouraging.
Microabrasion + adjuctive
treatment
 deep lesions may need a composite restoration
 the enamel surface of the lesion is roughened with acoarse diamond
bur to expose fresh enamel for etching.
 Etch for 60seconds instead of the usual 15-30sec.
(reason why because the mineral pattern and enamel density changes)

150. Laser Assisted Bleaching
Technique
 This technique achieves power bleaching process with the
help of efficient energy source withminimumside
effects. Laser whitening gel contains thermally absorbed
crystals, fumed silica and 35 percent H2O2. In
this, gel is applied and is activated by light source which
further activates the crystals present in gel, allowing
dissociation of oxygen and therefore better penetration
into enamel matrix.
 Following laser have been approved by FDA for tooth
bleaching: •
 Argon laser
 • CO2 laser
 • GaAlAs diode laser.

151.  Argon Laser
 • Emits wavelength of 480 nm in visible part of
spectrum
 •Activates the bleaching gel and makes the darker tooth
surface lighter
 • Less thermal effects on pulp as comparedto other
heat lamps.
 CO2 Laser
 •Emits a wavelength of 10,600 nm
 • Usedto enhance the effect of whiteningproduced by
argon laser
 • Deeper penetration than argon laserthus more
efficient tooth whitening
 • Moredeleterious effects on pulp than argon laser.
 GaAlAs Diode Laser (Gallium Aluminum–Arsenic)
 Emits a wavelength of 980 nm.

152. SAFETY ISSUES
“the dose makes the poison”-Ottoboni 1989

153. Is carbamide peroxide toxic?
 carbamide peroxide is formed from urea and
hydrogen peroxide. Urea moiety in nightgaurd
vital bleach is non toxic to the human body.
 The metabolism requires oxygen free
radicals,including H2O2.
 H2O2 is decomposed by enzymes particularly by
catalase and various peroxidases which are found
highest in liver spleen duodenum kidney, blood
and mucous membrane.
 in blood catalase degrade gram quantities of H2O2
in just few minutes.

154. Does carbamide peroxide
cause resorption?
 Invasive cervical resorption is seen very
occasionally in bleached root-filled teeth.
(FASARARO 1992)
 Main causes are trauma followed by heat and very
high conc for H2O2. ( COHEN & PARKINS 1970)
 Thus, only when a combination of high
concentration of H2O2 and heat are used on teeth
with a history of trauma the resorption will result.
 Incidentally there are no reported cases with
carbamide peroxide.

155. Carabamide peroxide cause
sensitivity???
 Increased sensitivity is associate dwith use of high
concentrations of H2O2 with heat.
 For nightgaurd vital bleaching ,neither heat or
high conc are used.

156. Hardness of teeth and
bleaching
 If needed, there are any changes in tooth hardness
by bleaching they are certainly likely to be less
than those from removal of the enamel prior to
veneer application or microabrasion. (HAYWOOD,
SHANNON)

158. Conclusion
 Noticeable discoloration of teeth is a physical handicap
which impacts the persons self image, self-confidence,
attractiveness and employability.
 It should not be therefor ebe dismissed as a matter of
no more than cosmetic importance.
 Bleaching is not achieved solely by a surface effect.
H2O2 dissociated from carbamide peroxide penetrates
through the enamel into the dentine.
 Low concentration gels are completely safe.
 When properly used there are no more than minimal
adverse effects on dental pulp or soft tissues of the
mouth and these are very transitory.

159. References
 BLEACHING TECHNIQUES IN RESTORATIVE DENTISTRY –
GREENWALL
 GROSSMAN’S ENDODONTICS
 COMPLETE DENTAL BLEACHING – RONALD.E.GOLDSTEIN
& DAVID.A.GARBER