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2. CONTENTS
Introduction
Common points about adhesives
Materials used as adhesives
Composites
Generations of adhesive
Other adhesive materials
Clinical application of adhesives–
Bonding in Orthodontics
Updates
Conclusion www.indiandentalacademy.com
3. INTRODUCTION
Tooth movement
Attachment of brackets on tooth
Banding
Bonding
Acid Etch technique – Buonocore – 1955
Newman – Epoxy resin 1965
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4. Benefits of bonding
Aesthetics
Easier plaque control
Decreased irritation of gingival
tissues
Absence of interproximal space after
the completion of treatment.
PATIENT:
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5. Benefits of Bonding
PRACTITIONER:
eliminates pre-treatment separation
of teeth & needless to mention it also
greatly decreases chair side time.
direct bonding makes it easier to
detect & treat dental caries
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6. ADHESION
“The state in which two surfaces are
held together by interfacial forces
which may consist of valence forces
or interlocking forces or both”
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7. ADHESIVE
“ is a material frequently a viscous fluid that
joins two surfaces together and solidifies
and therefore is able to transfer a load from
one surface to the other.
ADHEREND
Material to which an adhesive is
applied is called Adherend
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8. SURFACE WETTING & CONTACT ANGLE
“WETTING” use a fluid that will flow and “wet” an
adherend
“CONTACT ANGLE” which is nothing but an angle
formed by the adhesive with the adherend at
their interface.
IMPORTANCE
The smaller the contact angle, the better able,
is the adhesive to fill in irregularities in the
surface of the adherend.
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10. MECHANICAL :
INTERLOCKING OF ADHESIVE WITH
IRREGULARITIES IN THE SURFACE OF
THE ADHEREND.
ADSORPTION :
CHEMICAL BONDING BETWEEN THE
ADHESIVE AND ADHEREND
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11. ELECTROSTATIC:
THERE IS AN ELECTRICAL DOUBLE
LAYER AT THE INTERFACE OF A
METAL AND POLYMER THAT IS PART
OF THE TOTAL ADHESIVE SYSTEM
DIFFUSION :
INTERLOCKING BETWEEN MOBILE
MOLECULES, SUCH AS THE ADHESION
OF TWO POLYMERS THROUGH
DIFFUSION OF POLYMER CHAIN ENDS
ACROSS AN INTERFACE.
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12. Requirements for adhesive
systems
Wetting: An adhesive must give
good wetting of the adherend.
Thickness: Too great thickness
can lead to poor bond strength.
Strength: of the set adhesive
must be taken into consideration.www.indiandentalacademy.com
13. Viscosity: The adhesive should
have a suitable viscosity to enable
it to flow readily over the surface of
adherend
Dimensional Stability: The setting
time of the adhesive should occur
without excessive dimensional
changes i.e.., little expansion or
contraction.
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16. 2 basic types resins for orthodontic bonding
Acrylic
Diacrylate resins
/ Based on Self-curing acrylics
/ Methylmethacrylate monomer &
ultra fine powder
/ form linear polymers only
/ filled or unfilled forms
/ e.g Orthomite, Genie
/ Plastic brackets
/ Based on acrylic modified Epoxy
resin
/ Bis GMA or Bowen’s resin
/ Polymerised also by cross linking
into 3 dimensional network
/ Cross linking – greater strength
/ filled or unfilled forms
/ e. g Concise, Phase II
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19. TYPES-ACCORDING TO SIZE OF
FILLER PARTICLES
CONVENTIONAL 1-50 µm
MICROFILLED 0.04 µm
HYBRID
CLINCAL APPLICATION:
•LARGER FILLER PARTICLES-EXTRA BOND STRENGTH.
•CAREFUL REMOVAL IS NECESSARY DUE TO
ACCUMULATION OF PLAQUE.
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22. Conventional Curing lights:Conventional Curing lights: Use halogenUse halogen
bulbs filtered to produce blue light.bulbs filtered to produce blue light.
Cure adhesives under bracket in 20-30 sec.Cure adhesives under bracket in 20-30 sec.
High performance halogen curingHigh performance halogen curing
lights:lights:
80 watts tungsten/quartz/halogen bulb80 watts tungsten/quartz/halogen bulb
Cures under metal brackets in 8 seconds andCures under metal brackets in 8 seconds and
under ceramic brackets in 5 seconds .under ceramic brackets in 5 seconds .
Has boost mode to increase the output up toHas boost mode to increase the output up to
1000 watts. hence allows metal brackets to be1000 watts. hence allows metal brackets to be
cured in 5 secondscured in 5 seconds
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24. Plasma arc lights:Plasma arc lights:
generates a lot of heat and large fan isgenerates a lot of heat and large fan is
required.required.
Adhesive is cured in 5 seconds under metalAdhesive is cured in 5 seconds under metal
brackets and 3 seconds under ceramic bracketsbrackets and 3 seconds under ceramic brackets
Laser lights:Laser lights:
emits monochromatic coherent lightemits monochromatic coherent light
sourcesource
Generate lot of heatGenerate lot of heat
cumbersomecumbersome
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25. Led’s(LIGHT EMITTING DIODES)Led’s(LIGHT EMITTING DIODES)
1995 mills et al1995 mills et al
Solid state light emitting diode technologySolid state light emitting diode technology
10 sec cure10 sec cure
Cool, safe light, no damage to the tooth pulpCool, safe light, no damage to the tooth pulp
e.g.Ledmax-4e.g.Ledmax-4
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28. Composition:
ENAMEL STUCTUREENAMEL STUCTURE
Hardest mineralized tissue in body.Hardest mineralized tissue in body.
96% INORGANIC PORTION
Crystalline calcium hydroxy-apatite crystals
4% ORGANIC MATERIAL & WATER
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29. Structural unit of the enamel.
RODS &PRISMS.
KEY HOLE SHAPED.
CENTRAL BODY & EXTENSION TAIL.
INTERPRISMATIC MATERIAL.
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31. ACID ETCHING:ACID ETCHING:
REMOVAL OF SURFACE DEBRISREMOVAL OF SURFACE DEBRIS AIDS BONDING
PORES CREATED RESIN PENETRATES
CREATES TAG LIKE EXTENSIONS
MECHANICAL INTERLOCKING
INCREASES SURFACE ENERGY OF ENAMEL
IMPROVES WETTING.
Acid Etching
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32. Types of etchants
Strong acids 37% phosphoric acid for 15
seconds
provides a strong bond
.
Weak acids 2.5% nitric acid (or)
17% maleic acid for 30-60
seconds
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33. PATTERNS OF ACID ETCHINGPATTERNS OF ACID ETCHING
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39. SMEAR LAYER
WHEN WE PREPARE THE TOOTH , THE DENTINAL
SURFACE WITH OTHER PARTICLES FORM A SMEAR
LAYER WHICH WILL PREVENT THE COMPOSITE
BONDING
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40. CONDITIONERS
ACID SOLUTIONS
CAPABLE OF DISSOLVING (OR) AT LEAST
SOLUBILIZING THE SMEAR LAYER.
HENCE MORE EXPOSURE OF DENTINE TO
BONDING SYSTEMS.
REMOVAL OF SMEAR LAYER
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41. Examples of Conditioners
/35%-37% Phosphoric acid
/10% Phosphoric acid
/maleic acid
/EDTA
/Citric acid + 3% ferric chloride
37% phosphoric acid is a good
etchant and conditioner.
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44. RESIN CONTAINING
GLYCEROPHOSPHORIC ACID
DIMETHACRYLATE
BOWEN
N- PHENYL GLYCINE
&GLYCIDYL METHACRYLATE
(NPG-GMA)
BUONOCORE
(1956)
DRAWBACK •POOR DENTINE BONDING
•ENAMEL BONDING IS GOOD.
I - GENERATION
Bonding- Chelation of bonding agent to calcium of dentine
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45. II - GENERATION
(1978)
IONIC BONDING
DRAW BACK : BONDING TO SMEAR LAYER
REQUIRE MECHANICAL PREPARATION
Bis-GMA (or) HEMA
Unfilled resins
Calcium in dentine
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46. PRINCIPLE: PARTIALLY REMOVED (OR)
MODIFIED THE SMEAR LAYER
ETCHING OPENS DENTINAL TUBULES
PRIMER
META (or) BPDM
MODIFIES SMEAR
LAYER
ATTACHES TO
COMPOSITES
DRAWBACK: •PRIMER , DOES NOT PENETRATE THE SMEAR
LAYER
•ADHESIVE RETENTION DECREASES AFTER
SOME TIME
III - GENERATION
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47. IV - GENERATION
COMPLETE REMOVAL OF SMEAR LAYER
HYBRIDIZATION:REPLACEMENT OF HYDROXY-
APATITE AND WATER IN THE SURFACE DENTIN
WITH RESIN
HYBRID :RESIN IN COMBINATION WITH REMAINING
COLLAGEN FIBRE.
•TOTAL - ETCH TECHNIQUE.
•MOIST – DENTINE CONCEPT.
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48. V - GENERATION
SELF ETCHING PRIMERS
ONE –BOTTLE SYSTEM
•PRIMER AND ADHESIVES ARE COMBINED INTO ONE
SOLUTION
SHOW HIGH BOND STRENGTH VALUES BOTH TO
THE ETCHED ENAMEL AND DENTIN DUE TO
ADHESIVE LATERAL BRANCHES AND HYBRID
LAYER FORMATION.
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49. VI - GENERATION
ETCHNG WAS NOT REQUIRED AT LEAST AT THE
DENTINAL INTERFACE
They contained dentin conditioning agent as
one of their components
Drawbacks: Multiple components
Multiple steps
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50. VII - GENERATION
i-bondETCHING PRIMING
BONDING
Shear bond strength not affected –any type of curing
light
Similar adhesion to prepared and unprepared
enamel
Desensitizers were added.
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52. Setting Reaction: The hydrogen ions of the acid attack
the glass particles in the presence of water releasing
calcium, strontium, and aluminium ions. The metal ions
combine with the carboxylic group of the polyacid to
form the polyacid salts matrix and the glass surface is
changed to a silica hydrogel.
GLASS IONOMER CEMENTS
Invented -1969 reported 1971 by WILSON AND KENT
POWDER LIQUID
poly alkenoic acid
(carboxyl containing acid)
Flouroalumino
silicate glass
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53. GIC ‘S
ADVANTAGES DISADVANTAGES
FLUORIDE RELEASEFLUORIDE RELEASE
HYDROGEL PHASESHYDROGEL PHASES
MOISTUREMOISTURE
TOLERANCETOLERANCE
BOND STRENGTHBOND STRENGTH
LESS THAN THATLESS THAN THAT
OF COMPOSITE.OF COMPOSITE.
HYDROGEL PHASE:
Responsible for the uptake and release
of added environmental fluoride from
topical gels, rinses & dentifrices.
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54. GIC’s used for BONDING TOGIC’s used for BONDING TO
CERAMIC BRACKETSCERAMIC BRACKETS
CACCIAFESTA et alCACCIAFESTA et al (1998) (european journal of(1998) (european journal of
orthodontics)orthodontics)
The lower bond strength of glass ionomerThe lower bond strength of glass ionomer
cements might be advantageous with ceramiccements might be advantageous with ceramic
brackets where high bond strengths havebrackets where high bond strengths have
been associated with enamel damage.been associated with enamel damage.
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56. ADVANTAGESADVANTAGES::
polymerization proceeds faster than acid-basepolymerization proceeds faster than acid-base
reaction resulting in improvement of physicalreaction resulting in improvement of physical
properties, especially resistance.properties, especially resistance.
RMGIC-tolerates moisture similar to GIC’s.RMGIC-tolerates moisture similar to GIC’s.
Improved physical properties & more stableImproved physical properties & more stable
hydrogel phases compared with GIC’shydrogel phases compared with GIC’s
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57. polymerization of resin monomers hastens initialpolymerization of resin monomers hastens initial
hardening of RMGIC,s without interfering withhardening of RMGIC,s without interfering with
acid-base setting reactions (or) any other properties.acid-base setting reactions (or) any other properties.
Micromechanical interlockMicromechanical interlock
after polymerizationafter polymerization
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58. Silver et al :AJO (1995)
Found excellent long term adhesion
with such materials in the absence of
enamel etching
BISHARA et al : AJO (1999)
Advised etching of enamel for
sufficient bond strength
STUDIES :
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61. DIRECT BONDING
Easier, Faster
Less expensive
Drawbacks
proper positioning is crucial.
Has to be done rapidly and accurately.
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62. INDIRECT BONDING
Placing brackets in a model
Use template or tray to transfer
Common agent – “No-mix” chemically
activated materials
More useful in Lingual attachments
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63. Current categories of Adhesive bonding
According to Howard E. Srassler
(Compendium - June 2003 )
1.Total etch adhesive bonding
2. Self – etch adhesive bonding
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65. 1)Cleansing
2)Enamel conditioning or acid etching
3)Priming
4)Bonding
Bonding or adhesion to the
enamel is done in the
following procedure .
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66. Pre-treatment
Cleansing Improves wetting
Acid etching Improves adhesion
micromechanical retention.
Pre-treatment is necessary as mouth is
complicated by saliva ,acquired pellicle ,
different organic and inorganic
components of enamel and dentin.
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67. Salivary pellicle
When a tooth is cleaned in situ,
salivary proteins and glycoproteins with
a strong affinity for enamel very quickly
adsorb to the tooth surface and form a
very thin layer called salivary pellicle.
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68. CLEANSING
Removal of salivary pellicle &
contaminants
Material used – Pumice
Improves wetting
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81. Etch and deposit the primer
simultaneously
With this procedural sequence , it is
likely that the under filling of the
inorganic depleted zones will not
occur.
1 unit contains enough material for one
arch.
SELF ETCHING PRIMERS
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82. Etching depth & the resin
penetration depth are identical
Can be used for metal & ceramic
brackets.
It is a hydrophilic primer-
tolerates both moist & wet
conditions.
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94. Moisture Insensitive Primer
Bonding can be done in the presence of
Moist environment.
Requires moisture for the initiation of
polymerization.
MIP,s
Arndt kloche et. al. Angle orthodontist
2003 August.
Hydrophilic primer – from 3rd generation
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95. Why Moisture control is
important?
Surface energy reduced – less favourable
for bonding
Porosities are plugged – reduced no of
tags
Difficult anatomical areas
2nd
molar
Lingual surfaces of lower teeth
Partially erupted teeth
Surgically exposed teeth
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97. - HEMA – Hydroxy ethyl methacrylate
( main Hydrophilic component )
- CDMA – Citric acid
( allows greater cross linking )
- GDMA – Diluent + hydrophilic monomer
/ Same function as CDMA
/ The Hydrophilic monomer takes
Oral fluid & so fluoride uptake
- Acidic Co-polymer
/ Greater cross linkingwww.indiandentalacademy.com
98. -CPQ / Amine
-Photo initiator
- H2O - Solvent
( Water normally interferes with
adhesive if not removed.
But in Transbond, Water induces
Partial ionization of Carboxyl groups
& an inert dilution effect without
Activating any setting mechanism )
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99. Studies
Wet Conditions
Higher bond strength with MIP in
1 & 24 hours
Dry Conditions
Conventional primer showed
higher strength in 1 & 24 hours
/ Robert A Miller ( Orthodontic perspectives, 1998)
/ Ramkumar Grandhi et al ( orthodon dentofacial orthop, 2001)
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100. THERE ARE OCCASIONS WHERETHERE ARE OCCASIONS WHERE
IT IS DESIRED TO INCREASE THEIT IS DESIRED TO INCREASE THE
BOND STRENGTHS OF NO MIX-BOND STRENGTHS OF NO MIX-
ADHESIVES.ADHESIVES.
•NON COMPLAINT PATIENTSNON COMPLAINT PATIENTS
•HYPOCALCIFIED TOOTHHYPOCALCIFIED TOOTH
•FLOUROSED ENAMELFLOUROSED ENAMEL
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101. ADHESION PROMOTORSADHESION PROMOTORS
Bond chemically to metalBond chemically to metal IntermediateIntermediate resinsresins
4-META4-META
10-MDP10-MDP
Sun Medical,s Superbond C&BSun Medical,s Superbond C&B
ALL-BOND2ALL-BOND2
Reliance metal primerReliance metal primer
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102. FLUORIDE RELEASING ADHESIVESFLUORIDE RELEASING ADHESIVES
FLUORISED IONS CAN BE SUBSTITUTEDFLUORISED IONS CAN BE SUBSTITUTED
FOR HYDROXY GROUPS OFFOR HYDROXY GROUPS OF
HYDROXYAPATITE AND THESEHYDROXYAPATITE AND THESE
FLUORISED TEETH ARE MORE RESISTANTFLUORISED TEETH ARE MORE RESISTANT
TO DENTAL CARIES.TO DENTAL CARIES.
RMGIC-FUJI ortho LCRMGIC-FUJI ortho LC
PMCR-Transbond XT,3M sPMCR-Transbond XT,3M s
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103. ADHESIVE PRECOATED BRACKETS
(1992)
UNITEK /3M
COOPER et al
Consistent quality and quantity of adhesive
Reduced waste
Easier clean up
Same composition as in
transbond adhesive
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104. ADHESIVE PRECOATED
BRACKETS
Reduced Chair time
Individual packaging- aids
identification and orientation
Improved Cross-infection control
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111. DORON HARARIDORON HARARI et al (AJO) 2003et al (AJO) 2003
(BIFUNCTIONAL MOLECULE)(BIFUNCTIONAL MOLECULE)
Porcelain facetsPorcelain facets AdhesivesAdhesives
BONDING TO NON ENAMEL SURFACESBONDING TO NON ENAMEL SURFACES
““PORCELAIN”PORCELAIN”
BONDING OF CERAMIC BRACKETS
MECHANICAL RETENTION OF ADHESIVE TO BRACKET
BASE
PREPARING THE PORCELAIN SURFACE
SILANE COUPLING AGENT
9.6%“HF” gels -2-4 minutes are used for etching
porcelain surfaceswww.indiandentalacademy.com
112. BONDING TO CERAMICBONDING TO CERAMIC
RESTORATIONSRESTORATIONS
Fine diamond burFine diamond bur
SandblastingSandblasting
Micro-etching with aluminoMicro-etching with alumino
silicatessilicates
5%HCL5%HCL
Silica coatingSilica coating
Surface conditioning methodsSurface conditioning methods
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113. BuyukyilmazBuyukyilmaz T AND ZachrissonT AND Zachrisson (1998)(1998)
ANGLE ORTHODONTISTANGLE ORTHODONTIST
In bonding to gold intra oralIn bonding to gold intra oral sandblastingsandblasting
is superior tois superior to roughening withroughening with
diamond burdiamond bur
Tin plating improves bond strengths butTin plating improves bond strengths but onlyonly
marginally . This procedure ismarginally . This procedure is notnot
recommended by the FDA and hencerecommended by the FDA and hence notnot
recommended for orthodonticrecommended for orthodontic purposes.purposes.
BONDING TO GOLD
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114. BONDING TO AMALGAMBONDING TO AMALGAM
Intra-oral sandblastingIntra-oral sandblasting for 2-4for 2-4
seconds at a distance ofseconds at a distance of 10mm.10mm.
Use aUse a METAMETA intermediate resinintermediate resin
withwith a short curing time sucha short curing time such asas
reliance metal primer.reliance metal primer.
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115. BONDING TO VENEERSBONDING TO VENEERS
Kao and johston(1991)journal of prostheticKao and johston(1991)journal of prosthetic
dentistry.dentistry.
Reported fracture incidence on debondingReported fracture incidence on debonding
orthodontic brackets from porcelain veneersorthodontic brackets from porcelain veneers
Lee –knight et al (1991)AJOLee –knight et al (1991)AJO
IT may be worth using a ceramic reinforcedIT may be worth using a ceramic reinforced
resin bracket , such as ormco spirit or GACresin bracket , such as ormco spirit or GAC
Elan , on veneers as these brackets areElan , on veneers as these brackets are
extremely easy to debond.extremely easy to debond.www.indiandentalacademy.com
116. ConclusionConclusion
/ Two primary strategies – Total etch & self etch
/ Both has advantages & disadvantages
/ Total etch – the only adhesive system with long term
data to support
/ Profession moving towards Self etch or all-in-one systems
/ Clinical success of bonding – in the hands of the clinician
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121. ADHESIVES CAN BEADHESIVES CAN BE
CLASSIFIED ACCORDINGCLASSIFIED ACCORDING
TOTO
TOLERANCE OF MOISTURETOLERANCE OF MOISTURE
BANDING (or) BONDINGBANDING (or) BONDING
METHOD OF CURINGMETHOD OF CURING
METHOD OF DISPENSINGMETHOD OF DISPENSING
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122. ACCORDING TO THE METHOD OF DISPENSINGACCORDING TO THE METHOD OF DISPENSING
PASTE /PASTE SYSTEMSPASTE /PASTE SYSTEMS SINGLE PASTE (OR)NO MIXSINGLE PASTE (OR)NO MIX
ADHESIVES (Syringe) Light CuredADHESIVES (Syringe) Light Cured
InitiatorInitiator ActivatorActivator
BenzoylBenzoyl
peroxideperoxide
TertiaryTertiary
amineamine
U-V LightU-V Light Visible LightVisible Light
Eg: Chemically activatedEg: Chemically activated
resinsresins
Eg: Light activated CompositeEg: Light activated Composite
resinsresins
Benzoyn
Methyl Ether
Camphoroquinone
(diketone)
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123. Delport & grobler (1988)
Odegaard & segner (1988)
Bradburn & ponder(1992)
AJO
Little difference in the bond
strength between paste/paste &
no mix adhesives.
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124. According to tolerance of moisture
HYDROPHOBIC e.g./ conventional BIS-GMA
These adhesives require etching and absolute
dry environment
HYDROPHILLIC e.g./GIC’S RMGIC’S
Achieves chemical adhesion without etching
and tolerates a little moisture
According to bishara et al (1997) AJO –
etching is required for bond strength.
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126. ACCORDING TO METHOD
OF CURING
CHEMICALCURED
e.g Fuji I(conventional GIC)
LIGHT CURED
e.g Transbond XL
DUAL CURE
e.g Reliance phase II dualwww.indiandentalacademy.com
127. POLYMERIZATION:
Chemical cure in 4 minutes by light in 30 seconds.
material can be “SNAP SET” in 10 sec by light c
and then allowed to cure chemically.
DUAL CURE
CHEMICAL CURE + LIGHT CURE
e.g. reliance phase II dual cure.
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128. ADVANTAGES
COMMAND SETTING
EXTENDED WORKING TIME
Smith & Shivpuja (1993)AJO
Evaluated dual cure adhesives and
gave similar bond strengths to chemically
cured and light cured materials.
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129. LASER
(Light Amplification of stimulated
emission of Radiation)
Von Praun Holfer and Arbell, Angle Orthodontist, 1993
Nd:YAG ( Neodymium Ytrium Aluminium Garment
Laser) - to etch Enamel
/ Conversion of Light energy to thermal energy
/ Thermally induced changes within Enamel to a
Depth of 16 to 20 microns
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130. ADVANTAGES
1)Esthetically superior
2)Faster and simpler
Less discomfort for the patient
Arch length is not increased by band
material and no band spaces to close
at the end of treatment .
Better access for cleaning
Mesiodistal enamel reduction is
possible during treatment.www.indiandentalacademy.com
131. Disadvantages
1)However a bonded bracket has a weaker
attachment than a cemented band .
2)Better oral hygiene is not guaranteed
especially if excess adhesive extends
beyond the bracket base.
3)Rebonding a loose bracket requires more
preparation than rebonding a loose band
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135. DIFFUSION:DIFFUSION:
PRECIPITATION OF SUBSTANCES ONPRECIPITATION OF SUBSTANCES ON
THE TOOTH SURFACES TO WHICH RESINTHE TOOTH SURFACES TO WHICH RESIN
MONOMERS CAN BOND MECHANICALLY (OR)MONOMERS CAN BOND MECHANICALLY (OR)
CHEMICALLY.CHEMICALLY.
MECHANICAL:MECHANICAL:
PENETRATION OF RESIN &PENETRATION OF RESIN &
FORMATION OF RESIN TAGS WITHIN THEFORMATION OF RESIN TAGS WITHIN THE
TOOTH SURFACE.TOOTH SURFACE.
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136. COMBINATION:COMBINATION:
OF THE PREVIOUS THREEOF THE PREVIOUS THREE
MECHANISMS.MECHANISMS.
ADSORPTION:ADSORPTION:
CHEMICAL BONDING TO THECHEMICAL BONDING TO THE
INORGANIC COMPONENT (HYDROXY-APATITE) ORINORGANIC COMPONENT (HYDROXY-APATITE) OR
ORGANIC COMPONENT MAINLY TYPE I OFORGANIC COMPONENT MAINLY TYPE I OF
COLLAGEN TOOTH STRUCTURE.COLLAGEN TOOTH STRUCTURE.
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137. Fluoride compared in our departmentFluoride compared in our department
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