bleaching of tooth

2. • INTRODUCTION
• HISTORY
• CAUSES OF DISCOLORATION
• INDICATIONS AND CONTRAINDICATIONS
• MATERIALS USED IN BLEACHING
• CHEMISTRY AND MECHANISM
• BLEACHING TECHNIQUES
• ADVANTAGES AND DISADVANTAGES
• CONCLUSION

3. The lightening of the color of a tooth through
the application of a chemical agent to oxidize
the organic pigmentation in the tooth is
referred to as bleaching.
Sturdevant

4. • In 1300’s the most requested dental service other than
extraction was tooth whitening.
• In 14th century, Guy De Chauliac cleaned teeth gentlywith
honey and burnt salt to which some vinegar was added.
• In 18th century, barbers surgeons applied, “Aquafortis” a
solution of nitric acid, after abrading enamel with coarse
metal files to whiten teeth.
• In1864 Truman used chlorine and acetic acid for non vital
tooth bleaching. The commercial derivative of this,
known as Labarrque’s solution.
• The first publication of bleaching was in 1877 by Chapple,
the agent of his choice was oxalic acid.

5. • In 1884, Harlan used hydrogen peroxide for the first time
which he called as hydrogen dioxide.
• In 1961, Spasser described Walking Bleach Technique.
• In the late 1960’s , a successful technique for home
bleaching was introduced by Klusmier, at which time he
discovered that 10% carbamide peroxide loaded in a
mouth guard with the intent to improve the gingival
condition also resulted in a bleaching effect.
• In 1976, Nutting and Poe introduced the walking bleach
technique which uses 35% hydrogen peroxide and sodium
perborate for nonvital bleaching.
• In 1989, Haywood and Heymann introduced “Night guard
vital bleaching” (10% carbamide peroxide).
• In 1996 Reyto introduced Laser tooth whitening.

6. • Extrinsic discoloration
Extrinsic stains are located on the outer surfaces of the
teeth.
• Intrinsic discoloration
Intrinsic stains are those which are internal or present
with in the tooth structures.
• Stain internalization
Those circumstances where extrinsic stain enters the
tooth through defects in the tooth structure .

8. Metabolic causes
• Alkaptonuria,-brown
• congenital erythropoitic porphyria –red -brown
• congenital hyperbilirubinaemia-yellow green
Inherited causes of discoloration
– Amelogenesis Imperfecta
– Dentinogenesis Imperfecta
– Dentinal dysplasias
– systemic syndromes
Vitamin D dependent rickets
Pseudohypoparathyroidism
Epidermolysis bullosa
Ehlers-Danlos Syndrome

9. Pulpal necrosis
Bacterial, mechanical, or chemical irritation to the pulp may
result in tissue necrosis and release of disintegration by-
products that may penetrate tubules and discolor the
surrounding dentin.

10. • Dentin hypercalcification
During trauma temporary disruption of blood supply occurs,
followed by destruction of odontoblasts. These are replaced
by undifferentiated mesenchymal cells that rapidly form
irregular dentin on the walls of the pulp lumen. As a result,
the translucency of the crown gradually decreases, giving rise
to a yellowish or yellow-brown discoloration.
• Pre-eruption trauma
• Discoloration of a permanent tooth may occur after trauma
to its primary counterpart.

11. Intra pulpal haemorrhage

12. Endodontic Restorative
Pulp tissue remnants Amalgam fillngs
Intracanal
medicaments
Pins& posts
Obturating materials Composites

13. remnants:
•Tissue remaining in the pulp chamber disintegrates gradually and may
cause discoloration.
•Pulp horns must always be included in the access cavity to ensure
removal of pulpal remnants and to prevent retention of sealer at a later
stage.
• Intracoronal bleaching in these cases is usually successful.
Intra canal medicaments:
Phenolics or iodoform-based medicaments

14. materials:
Incomplete removal of obturating materials and sealer remnants in
the pulp chamber, mainly those containing metallic components,
often results in dark discoloration.
This is easily prevented by removing all materials to a level just
below the gingival margin.
Silver amalgam:
Silver amalgam produces a stain ranging from slate gray to dark
gray.
Stains from amalgam are likely to occur when dentinal wall is thin
and the filling material almost shimmers through the enamel.
, periap
Discolo
it usua

15. • First reported in mid-
1950s, less than a
decade after
widespread use of this
antibiotic.
• Most susceptible to
tetracycline
discolouration during
their formation i.e.
during the II trimerster
in utero to roughly 8
years after birth.

16. Severity of the stains depends on the time, duration
and the dosage of the drug and also the type of
tetracycline.
 Chlortetracycline (Aureomycin): Gray-brown
 Dimethylchlortetracycline (Ledermycin): Yellow
 Doxycycline (Vibramycin): Does not cause
staining
 Oxytetracycline (Terramycin): Yellow
Under fluorescent light

17. I-Light yellow or gray stain
II-Yellow-brown or deeper gray stain
III-Brownish-yellow or blue-gray stain
with distinctive banding

18. May arise endemically from
naturally occuring water
supplies or from fluoride
delivered in mouth rinses,
tablets or toothpastes as a
supplement.
High concentration of
fluoride in excess of 1ppm is
believed to cause a metabolic
alteration in the ameloblasts
resulting in defective matrix
and improper calcification.
Mild- brown pigmentation
Moderate- flat gray or white flakes
Pitting- dark pigmentation with surface defects

19. Enamel becomes thinner
•Dentin becomes thicker
•More yellow or grayish yellow
Discoloration due to dental caries:
•opaque, white halo or gray
discoloration.
•Bacterial degradation of food debris in
areas of tooth decay or decomposing
filling can cause even deeper brown to
black discolorations.

20. Extrinsic tooth
discoloration has been
classified according to its
origin
•Metallic
•Non-metallic.
Metallic staining of teeth
may be associated with
occupational exposure to
metallic salts and with a
number of medicines
containing metal salts.
iron supplements
and iron foundry
workers
Black staining
Violet to black color Potassium
permanganate in
mouth rinses.
Golden brown Stannous fluoride
Grey color silver nitrate salt

21. surface deposits such as
plaque or the acquired
pellicle .
Tobacco(smoking) Tea stain Coffee stain
Stain induced by use of
chlorhexidine mouthwash
Stain from use of
antibiotics
Green stain from
chromogenic bacteria

22. Based on chemistry of the discoloration – Nathoo 1997
N1 type dental stain: The chromogens binds to the tooth
surface to cause tooth discoloration.
N2 type dental stain : The chromogen changes color after
binding to the tooth.
N3 type dental stain : The pre-chromogens binds to the
tooth and under goes a chemical reaction to cause a stain.

23. Mild discoloration on surface
• Evenly distributed discolorations without bands
or white spots
• Teeth discolored as their innate colors or ageing
• Hemorrhagic discoloration
• Discoloration of anterior teeth after rct
• Medication discoloration

24. • Sensitive teeth i.e. severe cases of attrition,
abrasion, erosion or abfraction.
• Cracks, hypoplastic or severely undermined
enamel.
• Extensive restorations.
• Discolorations in the gray, blue gray or black
range .
• Discolouration by metallic salts, particularly silver
amalgam,
• Enlargement of the pulp or other disease that
makes the tooth sensitive to bleaching solutions

25. • Generalized dental caries
• Lack of compliance
• Pregnancy and nursing
• Peroxide allergy: A carefully applied rubber dam
can help prevent reactions.

27. HYDROGEN PEROXIDE
CARBAMIDE PEROXIDE
SODIUM PERBORATE

28. •Various concentrations of this agent are available,
but 30 to 35% stabilized aqueous solutions
(Superoxol) are the most common.
•Clear, colorless, odorless liquid, stored in
lightproof amber bottles.
•Unstable and should be kept away from heat,
which could cause it to explode.
•Can alone be used or mixed with sodium
perborate into a paste for use in the ‘Walking
bleach’.
• Caustic and burns tissues on contact.
•Delivery in an alkaline medium improves its
oxidizing efficiency.

29. •Oxidizing agent is available in a powdered form or as various
commercial preparations.
•When fresh, it contains about 95% perborate, corresponding to 9.9% of
the available oxygen.
•Sodium perborate is stable when dry.
S.P + H2O  S.M.Borate + H2O2
S.P + H2O2 S.M.Borate + H20 + O2
•THREE TYPES OF SODIUM PERBORATE PREPARATIONS ARE AVAILABLE:
•Monohydrate
•Trihydrate
•Tetrahydrate
•They differ in oxygen content, which determines their bleaching
efficacy.

30. •THREE TYPES OF SODIUM PERBORATE PREPARATIONS ARE AVAILABLE:
•They differ in oxygen content, which determines their
bleaching efficacy.
Monohydrate
Trihydrate
Tetrahydrate

31. •Also known as urea hydrogen peroxide,
• Is a bi-functional derivative of carbonic acid
• Available in the concentration range of 3 to 45%.
• Popular commercial preparations contain about 10%
carbamide peroxide,
• mean Ph of 5 to 6.5.

32. C.P 3% H2O2 + 7% Urea
H2O2  H2O + 2(O) and Urea NH3 + CO2
H2O2 is the active ingredient whereas urea raises the ph of
the solution
Bleaching preparations containing carbamide peroxide
usually also include Carbopol, urea, glycerine, preservatives
and flavoring agents.

33. L
•A water-soluble polyacrylic acid polymer
•Thickening agent, resulting in better retention in the night
guard
•Increase in length of bleaching-solution strength for
carbamide peroxide
•Slows rate of oxygen release extending duration of
bleaching action.
• Improves shelf life.
Increase in length of bleaching-solution strength for
carbamide peroxide bleaching preparations with carbopol vs
those without carbopol.

34. The bleaching process is based on the oxidation of the
bleaching agent.
Oxidation is the chemical process by which organic
materials are converted into carbon dioxide and water.
The oxidation-reduction reaction that takes place in the
bleaching process is called the REDOX REACTION.
Before the bleaching process, tooth is the reducing agent
and bleaching material is the oxidizing agent.
After bleaching, tooth is oxidized i.e. organic pigment of
tooth is oxidized and the bleaching material is reduced.

35. Low PH
The free radicals produced by the peroxides are perhydroxyl and nascent oxygen.
Of these, the perhydroxyl is a more potent free radical, which is responsible for a
better bleaching action
High PH
The buffering of peroxide to a pH range of 9.5 to 10.8 provides a greater
amount of perhydroxyl free radicals.

36. High molecular weight Complex organic
molecules (chromogens)-unsaturated double
carbon bonds
+
Bleaching agent
Low molecular weight organic molecules
(relatively colorless)-saturated carbon bonds

37. Oxidation of beta carotene. A free radical acts at
the unsaturated (double) bond (jagged line),
producing two molecules of colorless vitamin A.

38. Prolonged use of a bleaching agent causes the whitening
action to slow down beyond a point during the treatment.
Ideally, this is the point at which whitening should be
terminated.
If the degradation process continues, there is further
decomposition of organic matrix, resulting in a total loss of
enamel matrix protein.

41. 1. Pt education and
informed consent
2. Careful diagnosis
a)Visual examination:
Thorough visual examination, which will generally indicate the cause
of dental staining and the extent and depth of discoloration.
b)Behavioral history:
Previous and current use of tobacco, coffee or tea, and highly colored
beverages and foods.

42. al
history:
•Focus on any systemic problems or medications that might have
affected .
• problems begin during critical periods of tooth development
• needs to be investigated through the prenatal period.
d)Determining soundness of individual teeth
vitality
•Periapical or other pathologic condition.
•Caries
•Defective restorations
•Any enlargement of the pulp

43. 3. Record keeping with photographs
and shade selection
Use intra oral video camera or
high quality 35-mm camera.
These photographs will provide
an excellent record of pre-
treatment state.
It also will help the patient to
later recall how he or she
looked before any treatment
and to recognize the cumulative
effect of what may be a gradual
improvement in tooth colour.
Before
After

44. Protective draping and eye wear
No local anesthesia is administered
(vital)

45. Application of Orabase/Vaseline on labial and lingual tissues
And vaseline on lips
Rubber dam of heavy gauze is used
Punched holes –smaller in size

46. Stabilization in the
cervical areas with
dental floss

47. A thorough prophylaxis, using Prophy-Jet 30 (Dentsply), will
enable
visualization of the extent of deep stains
better prepare the teeth for treatment.
may remove enough of extrinsic stain, calculus and plaque
to satisfy some patients without further bleaching.

48. Bleaching procedures can be classified depending upon
A. Tooth vitality - into:
a.
b.
Vital tooth bleaching procedures
Non-vital tooth bleaching procedures
B. Site/Venue of acquiring treatment, into:
a.
b.
In - Office / chair-side
Home bleaching / out of the office

49. Bleaching
Non vitalvital
In office Night
guard
Walking
bleach
In office

51. The techniques used for bleaching of vital teeth
IN-OFFICE BLEACHING: Also called as Chairside bleaching.
•Thermo/Photo Bleaching
•Bleaching using Mc Innes solution
•Power Bleaching
DENTIST PRESCRIBED HOME-APPLIED BLEACHING: -
•Matrix bleaching-or night guard vital bleaching
OVER-THE-COUNTER KITS
Whitening strips
Whitening pastes
Tray-based bleaching systems

52. a)

53. Apply etching solution
(37%phosphoric acid)
Wash the etching solution
After 10 secs
Chalky white appearance

54. SUPEROXOL Wet the gauze
Apply saturated gauze
to labial surface

55. On lingual surface
Protection lenses
for the pt

56. Keep the light about 30 cms (13 inches) from the teeth and
direct the beam to the surface to be bleached temperature
ranges from 115°-140°F.

57. Add new solution at
every 4 to 5mins
Use a timer
Removal of dam, wiping, rinsing and neutralization with Na gel

58. Great heat is generated during bleaching which can
result in tooth sensitivity.
Causes tooth dehydration
Uncomfortable for patient
Slower in action

59. In this technique, high intensity light, which was used as a heat
source, is replaced with conventional halogen units, plasma
arc lamps, LED lights, Xeno halogen lights and lasers.
ADVANTAGES
• Time factor(fast result)
• Avoids problems of home bleaching
DISADVANTAGES
• Caustic nature of 35-50% HP
• Increased in office time
• Dehydration of teeth resulting in false light shade
• Expensive

60. Energizing/activating
source
Dental chair light
Halogen curing lamp
Plasma arc bleaching unit
Diode laser
Ultrasonics

61. Tungsten-Halogen curing light:
- Curing light provides heat
- Time consuming
process(40-60sec/tooth)
Xenon Plasma arc light
Non laser, high-intensity light
Adv: Very fast 3sec/tooth
Dis adv: Thermal trauma to the pulp
and surrounding soft tissues

62. When the source ofactivation is laser it isknown as laser bleachingtechnique.
Types of lasers
1)Carbon dioxide
2)Argon
3)Diode

63. n
laser:
 A true laser is delivered to chemicalagent
 488nm WL, Blue light, absorbed by dark stains
 Action is to stimulate the catalyst in the chemical.
Adv:
-No thermal effect,
-Less dehydration of enamel,
-Less time(10sec/tooth)

64. Carbon dioxide laser:(10,600nm)
• Invisible infrared light, energy is emitted
in the form of heat
• Directly interacts with catalyst/peroxide
• Deeper penetration
Diode laser light:
- 830 and 980 nm
- It is ultra fast 3-5 sec to
activate the bleaching agent
Adv:
Produce no heat

65. Mixing hydrogen peroxide: (a) the powder is introduced to
the liquid by pressing down to the release cap; (b) arrow
shows the broken seat; the powder and liquid can now be
mixed by gentle agitation; (c) the activator is added and
the contents begin to gel; (d) the finished product – a
thick glue that can be placed on to the teeth.

66. Adv of laser bleaching
• Faster
• It may act as a jump start for difficult cases by helping to
remove difficult stains caused by tetracycline and fluorosis
Disadvantages
• Expensive
• Post operative sensitivity can be high.

67. Ultrasonictechnology(Soniwhite)
•Uses ultrasonic technology with 6-7.5% HP gel
•Two cycles of 5 mins

68. is mixed to get good consistency
A 2-3 mm layer of freshly mixed gel should be
applied to all the labial surfaces of teeth in the
smile zone and lipped over to cover the incisal
edges and extend slightly lingually or palatally
Activation with or without light source depends
on the bleaching system used.
Procedure:

69. The gel is left in place for a length of time
dependent on the system and the cocentration
of HP used, usually about 10mins, but can
range from 3-20 mins at a time.
Gel is suctioned off the teeth using high
volume suction, rinsed , wiped using damp
gauze before being lightly dried

70. • The application and activation procedure is repeated one
more time before final washing and drying of the teeth.
Power bleaching procedures usually involve three 10-minute
passes.
• Surrounding mucosa are examined for blanching or areas of
redness indicating hydrogen peroxide seepage through the
isolation.
• Areas of damage should be thoroughly washed with copious
amounts of water before the application of a neutralizing
agent, such as vitamin E, usually supplied within the bleaching
kits

71. • Polishing with a diamond polishing paste gives a high lustre.
• Application of a neutral colorless fluoride gel.
• Final shade assessment and postoperative photographs.
• Patients should be given postoperative instructions.

72. NIGHT GUARD BLEACHING/ HOME
BLEACHING TECHENIQUE
• Introduced by Dr. VanHaywood
and Dr. Harald Haymann in
1989.
• Dentist prescribed home bleach
technique.

73. • Home bleaching is a simple technique whereby, after an initial
consultation with the dentist, a mouth guard or tray is made
for the patient to bleach the teeth at home.
• The patient is given the bleaching materials (normally 10%
carbamide peroxide) to take home together with a bleaching
protocol.
• The patient applies the bleaching material into the tray. The
tray with the material is worn for several hours during the day
or at night depending on the patient's schedule, while the teeth
lighten.

74. Various names have been associated with
home bleaching are :
• Nightguard Vital Bleaching
• Matrix bleaching
• Dentist-assisted / prescribed home-applied bleaching
• Dentist-supervised at-home bleaching
• At-home bleaching

75. Advantages
• Simple and fast
• Simple for dentists to monitor without extended
clinical time.
• It is cost effective
• It is not usually a painful procedure.
• Patients can bleach their teeth at their convenience
• Results relatively quick.

76. s
• Patients need to participate actively in their treatment.
• The color change is dependent on the amount of time the trays
are worn.
• The system may be open to abuse by using excessive amounts
of bleach for too many hours per day.
• It is difficult for patients who react easily to tolerate the
bleaching trays in their mouth.

77. Clinical examination of all teeth
Pre-existing shade evaluation
Alginate impression of the arch
to be taken.

78. Model prepared
Block resin applied on the labial
surface of the teeth to be
bleached to form a small
reservoir for the bleaching agent.

79. BIOSTAR
Fabrication of bleaching tray is
done using BIOSTAR
Place the model on the base
section of the vacuum tray forming
machine. Ensure that the plastic
sheet is properly placed over the
model.
Model and tray material in
position

80. Plastic sheet is now more easily
removed from the press. Scalloping
the tray on the buccal / facial surface
of the model using a heated scalpel
blade. Tray trimmed 1mm above the
gingival margin.
Molded plastic tray
Polishing of the tray is done gently
with a special soft cotton wheel.
Finished tray placed back on the
cast to prevent distortion.
Finished upper tray

81. BRUSHING FLOSSING
Bleaching material is placed on the buccal surfaces of the tray

82. Gentle finger pressure is applied to the tray to improve retention and suction while
removing the excess material at the same time.
Insufficient material is placed into
the tray. The tray is over extended.
More material is added

83. STORAGE

84. • Familiarize the patient with the
use of bleaching agent and
wearing the guard, instruct the
patient that this procedure
should be performed 3-4 hours
per day or over night.
• Recall the patient every 2
weeks to monitor stain
lightening.10% carbamide
peroxide is used for this
technique ,this can be later
increased to 16%,or up to 20%
as per the case reqirements.

85. •Gingival irritation
•Soft tissue irritation.
•Altered taste sensation
•Tooth thermal sensitivity

86. • Active treatment
• Passive treatment
Active treatment
• Fluoride toothpaste
• Neutral sodium fluoride gel
• Potassium nitrate-fluoride gel

87. nt
The bleaching technique can be modified:
• Excess material is removed.
• Patient can use a bleaching gel with a lower concentration.
• Reduce daily treatment time or bleach every other night.
• Patient should not replenish the bleaching solution more than
once.
• Dentist can ensure that the tray is trimmed back further so that
it is not impinging on the gingiva.

89. solution
Old Mc Innes(Acidic
medium -4.6)
New Mc Innes(Alkaline
medium-9)
constituent Ratio constituent Ratio
Bleaching
enamel
30% H2O2 5 parts 30% H2O2 1 part
Etches
enamel
36% HCl 5 parts
20% NaOH 1 part
Removes
surface
debris
0.2% ether 1 part
0.2% ether 1 part

90. New McInnessolution
• HCL has some deliterious effects such as
 Loss of contour
 Irritation of gingiva
 Sensitivity of teeth
• Chen,Xu and Shing(1993)
• HCL replaced by NaOH 20%
• NaOH is highly alkaline in nature and therefore dissolves calcium at a
slower rate.
• Loss of contour is minimized.(Nagarani et al)

91. edur
e:
The solution should be freshly mixed and applied directly to the enamel
surface for 5min at 1-min interval
On completion of the bleaching, the solution is neutralized with a baking
soda solution and copious irrigation with water.
Bleached surface should be poolished with cuttle disc and a prophylactic
paste.
Procedure may have to be repeated 2 or 3 times before the desired shade is
obtained.

92. Fig. 20.13;Materials used for bleaching
: Application of Vaseline
20.15:Application of rubber dam
20.16:Application McInnes solution
20.17:Irrigation done with warm water
20.15:Applica

93. ASSISTED BLEACH TECHNIQUE OR WAITING ROOM
BLEACH TECHNIQUE
• This bleaching technique was invented by Den- Mat.
• The dentist applies the 35% carbamide peroxide into a
custom-made bleaching tray. After the excess material is
removed, the patient returns to the waiting room for a
period of about 30 minutes with the bleaching tray in the
mouth.
• After 30 minutes, the bleach is suctioned off the teeth
before rinsing. The procedure can be repeated 2 -3 times
more in one session.

94. COMPRESSIVE BLEACHING TECHNIQUE
• This technique, reported by Miara, suggests that the Power
bleaching technique can be made more effective by
compressing the gel against the teeth. In order to enable the
permeation of oxidizing ions through the enamel, the
nascent oxygen must be guided under pressure.
• The procedure involves the usual isolation and placement
of 35 % hydrogen peroxide gel in custom made tray, which
is put in place and any excess material is removed before
the lingual and buccal edges of the tray are sealed with light
cured resin material to prevent any leakage during
decomposition.

95. • Once edges are sealed , the gel is activated using either a
halogen light or plasma arc.
• After 30 minutes the gel and isolation are removed and teeth
are washed .
Sealing the margin of the tray with
composite resin

96. Vivastyle paint on
The professional varnish system for whitening teeth

97. Why use a varnish system ?• Vivastyle paint on is insoluable in water. Consequently, the
varnish is not prematurely washed off the teeth by saliva.
• Vivastyle paint on contains 6% carbamide peroxide when
applied. This component releases oxygen , which gently
lightens stains. Once it has dried, its concentration is about
five times higher.

98. Steps of application
dispens
ing dish for single use

99. Brushing and flossing of teeth before application of varnish

100. Drying with blotting Paper Applying protective Gel

101. Vivastyle paint on is applied directly to the teeth with
a brush and allowed to dry for 30 seconds

102. The dried varnish remains on the teeth for 20 minutes
and is subsequently removed with a toothbrush.
APPLICATION OPTIONS
Once daily for 20 min. over a period of 14 days.
Twice daily for 20 min. over a period of 7 days .

103. CLINICALRESULTS
-Noticeable whitening of teeth after just a few days
-Less irritation

104. Advantages
• professional tooth whitening without a tray, as
– Patients find tray application uncomfortable
– Patients are looking for a more cost-effective alternative
• smooth integration into daily schedule
• gentle application
• touching up of previously whitened teeth

105. OVER THE COUNTER PREPARATIONS
Whitening strips(The Trayless Approach to Tooth
Whitening)
Thin,flexible polyethylene strips coated one side with a
film of H2O2
Worn for 30mins , twice a day

106. Duration:
6% coated H2O2 worn over 14 days
10% coated H2O2 worn over 10 days
Adv:
No tray is needed
Less visible
No gagging, salivation, speech problem, jaw joint
problem.
More convenient & compatible

107. Fig. 20.31

108. It is a procedure in which a microscopic layer of enamel
is simultaneously eroded and abraded with a special
compound leaving a perfectly intact enamel surface
behind.
INDICATIONS
 All surface stains from external sources such as tea, coffee ,
tobacco
 Incipient carious lesion, usually located near the gingival
margin, appear as opaque or chalky white when dried but are
invisible when hydrated.
 Developmental discoloured spot ,may be traumatic event or
idiopathic
 Surface discolouration due to fluorosis , if the discolouration is
within 0.2 – 0.3 mm removal depth limit.

109. •Contraindications
Deep enamel and dentin stains
•Compound used( Croll)
Paste containing 11%HCl and silicon carbide particles
(marketed as Prema)

110. M ICROABRASIONTECHNIQUE
Compound applied with ahand application device or with a rubber cup in a
low-speed hand piece. Periodically the paste is rinsed away to assess defect
removal. Care must be taken not to remove exessive tooth structure.
The treated area is polished with a fluoride containing prophy paste to restore
surface luster. Immediately following treatment a topical fluoride is applied to
enhance remineralization. Final results are seen in fig.

112. NVA
ON
IT
L
BLEACHING
• Darkening and loss of translucency may follow loss of vitality, both before
and subsequent to endodontic therapy.
In case of
• Acute trauma.
• Seepage of toxins from a necrotic pulp
• Staining form medicaments, cements, metal posts , or the optical effectsof
dehydration

113. Successful bleaching depends upon two important criteria-
The root canal obturation must be complete. In order to
prevent an endodontic failure, the root canal system must be
filled in three dimensions
The remaining tooth structure must be intact

114. Intracoronal bleaching:
The material is sealed into the access cavity during in-office visits
and requires frequent changing of dressings:
• Walking Bleaching Technique: Sodium perborate and water
sealed into the tooth .
• Modified intracoronal bleaching technique : Various
increasing hydrogen peroxide concentrations and sodium
perborate is used.
• Intracoronal bleaching using the thermocatalytic technique or
other forms of heat or heating instruments

115. Open chamber bleaching.
Combining intra- and extracoronal bleaching; the material
is applied into the pulp chamber directly and retained with a
home bleaching matrix.
• Inside/Outside technique with bleaching tray using different
concentrations of Carbamide peroxide
Closed chamber bleaching
The bleaching material is placed on the external surfaces of the
tooth.
• Power bleaching using 35% hydrogen peroxide
• Nightguard Vital Bleaching using 10%, 15% or 20% applied only to
the non-vital tooth in the tray

116. INDICATIONS CONTRAINDICATIONS
Discoloration of pulp chamber
origin
Superficial enamel discolorations
Dentin discolorations Defective enamel formation
Discolorations not amenable to
extra coronal bleaching
Presence of caries
Discolored composite restoration
Severe dentin loss

118. Familiarize the patients with
possible causes of
discoloration. Radiograph to
assess the status of periapical
tissues and quality of
endodontic obturation.
Evaluate tooth color with the shade guide
Isolate the tooth with rubber dam

119. Cavit and GIC
base at least 2
mm thick to
cover the
endodontic
obturation.

120. Remove all restorative material from the access
cavity. Remove all the materials to a level just
below the labial gingival margin
Apply a sufficient thick layer , at least 2mm of
protective white cement barrier ,such as zinc
phosphate cement ,GIC, intermediate restorative
materials
The material is placed at correct depth snugly,
using a flat plastic or endodontic plugger

121. Prepare the walking bleach paste by mixing
sodium perborate and inert liquid , such as water
etc.
Pack the pulp chamber with the paste. remove
the excess liquid by tamping with a cotton pellet.
Carefully pack the temporary filling at least 3mm
thick, to ensure a good seal

122. PRE AND POST OPERATIVE
Before After

123. • Hydrogen peroxide gel (30-35%) is
placed in the pulp chamber and
activated either by light or heat.
• The temperature is usually between 50
and 60°C maintained for 5 minutes
• The gel is removed by washing with
water for a further minute. The tooth
is dried and the 'walking bleach
technique' is used between visits until
the tooth is reviewed 2 weeks later to
assess if further treatment is
necessary.

124. • External root resorption
• Chemical burns
• Damage to the restoration
Suggestions for safer non vital bleaching
 Isolate the tooth effectively
 Protect oral mucosa- Vaseline, catalase applied to oral tissues
 Verify adequate endodontic obturation.
 Use protective barriers.
 Avoid acid etching
 Avoid excessive heat
 Recall patients periodically.

125. • Inside/Outside bleaching technique
•Internal/External bleaching,
•Patient-administered intracoronal bleaching technique
•Modified walking bleach technique.
The technique combines the intracoronal bleaching technique with
the home bleaching technique. It is used to lighten non-vital teeth
in a simple manner.
After barrier replacement the access cavity is left open so that the
bleaching material which is normally 10% carbamide peroxide,
can be placed into the pulp chamber while the bleaching tray is
applied to the tooth to retain the material on the tooth. Bleaching
can thus take place internally and externally at the same time.This
technique is a modification of the intracoronal bleaching
technique.

127. Benefits
• More surface area is available both internally and externally for the
bleach to penetrate.
• A lower concentration (10% Carbamide peroxide with neutral pH) of the
bleach is used.
• This technique will hopefully eliminate the incidence of cervical
resorption that has been reported with the conventional intracoronal
bleaching technique.
• The need to change the access cavity dressing is eliminated as the
access cavity is left open.
• Treatment time is reduced to days rather than weeks
• No heat is required to activate the bleaching material.

128. There have been many reports regarding the relationship
between bleaching agents and the bond strength of composite
materials to enamel following bleaching. Many investigators
have reported a severe decrease in the average bond strength
of composite to bleached versus unbleached enamel .
• Surface roughening and etching may occur and tensile
strength is affected (Singleton and Wagner ,1992)
• It has been noted that the resin tags are reduced in number,
less defined and shorter in bleached enamel .
• Bleaching has been shown to increase the micro leakage of
existing restorations.

129. Effect of bleaching agents on other materials:
• Microstructural changes in amalgam.
• Alteration in the matrix of glass ionomers.
• IRM becomes cracked and swollen.
• Provisional crowns made from methyl methacrylate
discolor and turn orange.

130. BriteSmile Whitening Pen
• Easy to use
• Dries rapidly.
• Just two easy 30-second
applications a day for two weeks,
then use as desired.
• Each Whitening Pen last for 30
days of whitening applications

131. Colgate visible white
ZOOM whitening system
Dr-collins- bleaching system

132. • Nite White ACP has been
clinically proven to
remineralize teeth while
also whitening them.
• Nite White rebuilds tooth
enamel, making teeth
stronger and less
susceptible to caries.

135. conclusion
The use of bleaching agents provides an effective and conservative
approach to the removal of unesthetic discolorations from vital &
non-vital teeth. As with all therapeutic modalities, proper diagnosis
and planning is essential.

139. Argon laser:



Adv:
TYPES OF LASERS INBLEACHING

140. Carbon dioxide laser:
• I
e
•
•
Diode laser light (power bleaching)
Adv:

141. Othertechniques
Waiting room bleaching (35% CP)
• Uses custom made tray
• gel injected from syringe under hot water
• Placed in mouth, excess wiped
• Asked to sit in waiting room for 30 mins
• Gel suctioned ,rinsed and dried.

142. • Power bleaching technique reported by Miara
• 35% HP gel
• Custom made tray is sealed using light cured resin
material
• Light activated for 30 mins
Ultrasonic technology(Soniwhite)

143. HISTORY
CLASSIFICATION
BUR BLADE DESIGN
ADDITIONAL FEATURES IN HEAD DESIGN
MODIFICATIONS OF BLADE DESIGN
FACTORS AFFECTING CUTTING EFFECIENCY

144. HISTORY
CLASSIFICATION
BUR BLADE DESIGN
ADDITIONAL FEATURES IN HEAD DESIGN
MODIFICATIONS OF BLADE DESIGN
FACTORS AFFECTING CUTTING EFFECIENCY