The document discusses the history and principles of adhesive dentistry and orthodontic bonding. It begins by tracing the origins of adhesive dentistry back to 1955 when acids were found to improve resin bonding to teeth. It then outlines the basic 6 step process for successful bonding: cleaning, etching, sealing, bonding, cleaning, and curing. The document delves into each step in detail and discusses improvements in bonding materials and techniques over time, from early generation bonding agents to modern multi-step and self-etch systems. It also reviews considerations for bonding to different tooth structures like enamel, dentin, porcelain, gold, and amalgam.

1. Guided by: Presented by:
Dr. Mridula Trehan Dr. Deeksha Bhanotia
Professor & HOD MDS First Year.
Department of Orthodontics
& Dentofacial Orthopaedics.
1

2. As we enter the new millennium, it is important
for us to examine the past.
The principles of adhesive dentistry date back to
1955 when Buonocore, using techniques of industrial
bonding, postulated that acids could be used as a
surface treatment before application of the resins.
Kharbanda OP. Orthodontics Diagnosis and Management of
Malocclusion and Dentofacial Deformities(2nd Edition).Elsevier: 346-
354 2

3. The basic principles for a successful bonding
are
(1) Cleaning and Polishing.
(2) Etching Enamel.
(3) Sealing.
(4) Bonding.
(5) Cleaning.
(6) Curing.
Kharbanda OP. Orthodontics Diagnosis and Management of Malocclusion
and Dentofacial Deformities(2nd Edition).Elsevier: 346-354
3

4. Cleaning is done on the labial or lingual adhesive surface
of teeth.
 Should be free of calculus and plaque for efficient
bonding.
This is most frequently performed by using pumice
with rubber polishing cup.
Before commencing the etching procedure, proper moisture control
is obtained.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique
(2nd edn).St Louis, Mosby 1994: 542-623. 4

5.  After the rinse, salivary control and maintenance of a
completely dry working field is absolutely essential.
Devices used are:
1. Lip expanders and/ or cheek retractors.
2. Saliva ejectors.
3. Tongue guards with bite blocks.
4. Salivary duct obstructers.
5. Cotton or gauze rolls.
6. Antisialogogues .
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd
edn).St Louis, Mosby 1994: 542-623. 5

6.  For simultaneous premolar to premolar bonding devices like lip
expanders , saliva ejector etc. is used.
 For bonding on the lingual surfaces saliva evacuator-bite blocks
have been developed.
 Antisialogogues (eg: Banthine, Pro-Banthine, Atropine Sulfate
etc.) are being used. (When indicated: Banthine tablets
(50mg/45kg body weight) is indicated 15 minutes before bonding.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd edn).St Louis, Mosby
1994: 542-623.
6

7. Etchants are provided as gel or an acid solution.
Etchant is applied over the enamel surface with a foam pellet
or brush.
Acid gels provide better control over the area to be etched as
they are easy to control in terms of flow.
The acid is gently rinsed off after 30 seconds with abundant
water supply.
This is followed by drying the tooth surface with moisture
free, oil free air.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd edn).St Louis, Mosby 1994: 542-623. 7

8. Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd edn).St
Louis, Mosby 1994: 542-623.
8

9. Acid etching transforms the smooth enamel
into a very irregular surface and increases
its surface energy.
The resin penetrates into the surface by
capillary action.
Monomers in the material polymerize and
material becomes interlocked with the
enamel surface.
The formation of resin microtags within the
enamel surface is the fundamental
mechanism of adhesion of resin to enamel.
9
Roberson TM,Heymann HO,Swift EJ. Orthodontics: Sturdevant’s Art and
Science of Operative Dentistry (4th edn).Mosby 2002: 2

10.  Enamel etching results in three different
micromorphologic patterns:
Type I etching pattern involves the
dissolution of prism cores without
dissolution of prism peripheries.
Type II etching pattern involves the
dissolution of peripheral enamel and cores
are intact.
Type III etching pattern involves
dissolution of areas that resemble the other
two patterns and areas whose topography is
not related to enamel prism morphology.
10
Roberson TM,Heymann HO,Swift EJ. Orthodontics: Sturdevant’s Art and
Science of Operative Dentistry (4th edn).Mosby 2002: 238.

11. 1. Effect of Concentration of Etching Agent on bond strength:
Application of 50% phosphoric acid for 60 seconds results in
formation of mono calcium phosphate monohydrate precipitate that can be
rinsed off. Concentration below 27% may create dicalcium phosphate
monohydrate precipitate that cannot be easily removed and consequently
interfere in adhesion. Concentration above 40% seem to dissolve less calcium
and result in etch patterns with poorer definition. So, concentration in the
range of 30% to 40% is used.
2.Effect of Etching Time on bond strength:
An etching time of 60 seconds was originally recommended for
permanent enamel using 30% to 40% phosphoric acid.While one study
concluded that shorter etch times resulted in lower bond strengths other
studies in vitro demonstrated similar bond strengths and microleakage for
etching times of 15 and 60 seconds.
11
Roberson TM,Heymann HO,Swift EJ. Orthodontics: Sturdevant’s Art and
Science of Operative Dentistry (4th edn).Mosby 2002: 238.

12.  3. Effect of Etching time on bond strength in
deciduous teeth:
Studies done has indicated that increase in etching time in primary teeth
as compared to 60 second etching time does not increase the bond strength.
Deborah A. Redford article
 4. Effect of Etching time on bond strength in fluorosed
teeth:
Teeth with higher concentration of fluoride are more resistant to acid
etching than normal teeth and may require an extended etching time.
For moderately and severe fluorosed teeth etching time should be
prolonged to 90 sec to remove both hyper mineralized layer and organic
network as well as produce typical etching patterns.
12

13.  After the teeth are completely dry and appear frosty white,
a thin layer of sealant is painted over the entire etched
surface.
Small foam pellets, brushed with single gingivo- incisal
stroke may be used for application of primer.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd
edn).St Louis, Mosby 1994: 542-623.
13

14.  Sealant increases bond strength, protects enamel from
consequent demineralisation caused by acid etching
procedure and improves resistance to microleakage.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd
edn).St Louis, Mosby 1994: 542-623. 14

15.  Enamel Bonding Systems:
Consists of unfilled liquid acrylic monomer
mixture placed onto acid etched enamel. The monomer
flows into interstices between and within enamel rods.
Enamel bonding depends on resin tags becoming
interlocked within the surface irregularities created by
etching.
The bonding system copolymerizes with the
matrix phase of the composite, producing strong
chemical bonding.
Bond strengths of approximately 20 MPa is
clinically acceptable.
Sturdevant 183
15

16. 1.FIRST GENERATION
 In 1956, Buonocore and colleagues demonstrated that use of a
glycerophosphoric acid dimethacrylate-containing resin would
bond to acid-etched dentin.
 This bond was believed to be due to the interaction of this
bifunctional resin molecule with the calcium ions of
hydroxyapatite.
 Immersion in water would greatly reduce this bond.
 Shows low bond strength.
16
Kugel G, Ferrari M. The science of bonding:from first to sixth generation.American dental
association ; 131:20

17. 2. SECOND GENERATION
 In the late 1970s, the second-generation systems were
introduced.
 The majority of these incorporated halophosphorous esters of
unfilled resins such as bisphenol-A glycidyl methacrylate, or
hydroxyethyl methacrylate.
 The mechanism by which these second-generation systems
bonded to dentin were postulated to be through an ionic bond
to calcium by chlorophosphate groups.
 Adhesion was for short term, the bond eventually hydrolysed.
17
Kugel G, Ferrari M. The science of bonding:from first to sixth generation.American dental
association ; 131:20

18. 3. THIRD GENERATION
 With the third-generation systems, the acid etching of the
dentin partially removes and/or modifies the smear layer.
 The acid opens dentinal tubules partially and increases their
permeability.
 The primer contains hydrophilic resin monomers which
include hydroxyethyl trimellitate anhydride, and biphenyl
dimethacrylate.
 The primers contain a hydrophilic group that infiltrates the
smear layer, modifying it and promoting adhesion to dentin,
and the hydrophilic group of the primer creates adhesion to the
resin.
Kugel G, Ferrari M. The science of bonding:from first to sixth generation.American dental
association ; 131:20
18

19. 4. FOURTH GENERATION
 The complete removal of the smear layer is achieved with fourth-
generation bonding systems.
 Fusayama and colleagues tried to simplify bonding to enamel and
dentin by etching the preparation with 40 percent phosphoric acid.
 Unfortunately, it was not understood that this procedure over etched
dentin and resulted in the collapse of exposed collagen fibers.
 In 1982, Nakabayashi and colleagues reported the formation of a
hybrid layer resulting from the polymerized methacrylate and
dentin.
 The hybrid layer is defined as “the structure formed in dental hard
tissues by demineralization of the surface and subsurface, followed
by infiltration of monomers and subsequent polymerization.”
Kugel G, Ferrari M. The science of bonding:from first to sixth generation.American
dental association ; 131:20
19

20. 5. FIFTH GENERATION
 To simplify the clinical procedure by reducing the bonding steps
and thus, the working time, a better system was needed.
 Also, clinicians needed a better way to prevent collagen collapse
of demineralized dentin.
 The fifth generation of bonding systems was developed to make
the use of adhesive materials more reliable for practitioners.
 The fifth generation consists of two different types of adhesive
materials: the so-called “one-bottle systems” and the self-etching
primer bonding systems.
 These bonding systems create a mechanical interlocking with
etched dentin by means of resin tags, adhesive lateral branches
and hybrid layer formation and show high bond-strength values
both to the etched enamel and dentin.
 Kugel G, Ferrari M. The science of bonding:from first to sixth generation.American
dental association ; 131:20
20

21.  SIXTH GENERATION
 Recently, several bonding systems were developed and
proposed as the sixth generation of adhesive materials. These
bonding systems are characterized by the possibility to achieve
a proper bond to enamel and dentin using only one solution.
 These materials should really be a one-step bonding system.
Unfortunately, the first evaluations of these new systems
showed a sufficient bond to conditioned dentin while the bond
with enamel was less effective.
21
Kugel G, Ferrari M. The science of bonding:from first to sixth generation.American
dental association ; 131:20

22.  Immediately after all teeth to be bonded have been
painted with sealant, the operator should proceed with
actual bonding of the attachments.
The recommended bracket bonding procedure consists of
following steps:
1. Transfer.
2. Positioning.
3. Fitting.
4. Removal of excess.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique
(2nd edn).St Louis, Mosby 1994: 542-623.
22

23.  The bracket is gripped with a pair of cotton pliers or a reverse
action tweezer and mixed adhesive is applied to the back of the
bonding base.
 The bracket is immediately placed on the tooth close to its correct
position.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd
edn).St Louis, Mosby 1994: 542-623.
23

24.  Primer is painted on the bracket base mesh and optimum
amount of adhesive is then applied with an applicator.
The bracket is placed on the pre-determined/ calibrated
area of tooth as precise as possible in the first go.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd
edn).St Louis, Mosby 1994: 542-623. 24

25.  A flat end push scaler or the reverse end of the bracket
holder is used to orient the bracket parallel to the long
axis inciso gingivally and in the centre of the tooth
surface mesiodistally.
 For vertical positioning Boon’s gauge or height guides
are used.
 A mouth mirror is essential for proper horizontal
positioning.
Graber TM, Vanarsdall RL. Orthodontics: Current
Principles and Technique (2nd edn).St Louis, Mosby
1994: 542-623. 25

26. Bonding Materials:
Composite resins:
 Composite resins are combinations of silane-coated
inorganic filler particles with dimethacrylate resin,
either bisglycidyl methacrylate (BISGMA) or
urethane dimethacrylate (UDMA).
In some cases, a proportion of a lower-
molecularweight monomer such as triethyleneglycol
dimethacrylate (TEGDMA) is introduced to lower
the viscosity.
26

27.  Glass ionomer cements:
Glass ionomer cements have distinctive
properties that make them potentially useful in
clinical orthodontics.
First, they adhere to both enamel and
metal.
Second, these cements release fluoride and
therefore may prevent enamel decalcification.
Third, glass ionomer cements can be removed
with much less difficulty than composite resin
after debonding,because the cement remaining on
the tooth surface can be desiccated by simply
air drying it, thus rendering it more friable.
27

28. Recent research also demonstrated that the use of
resin modified glass ionomer cement (RM-GIC) alone
can significantly decrease enamel demineralization
compared with composite resin.
Although the increased fluoride release from the
glass ionomer cements has the potential for lessening
decalcification around orthodontic brackets, Shear Bond
Strength of the material is relatively low
compared with composite adhesive.
28

29.  1.Bonding to porcelain :
.
The most common etchant used is 9.6%
hydrofluoric acid in gel form for 2 to 4
minutes.
Other studies indicate that 1.23 or 4%
APF solution or gel, containing sodium
fluoride, phosphoric acid may provide
equivalent bond strength.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd
29

30. 2.Bonding to Gold:
Roughening the gold surface with green stone was found
by Wood et al. to significantly increase bond strengths to a
highly filled resin system.
Intaoral Sandblasting technique can also be used to
roughening the gold surface.
Aluminium Oxide particles at approximately 7kg/ sq. cm
pressure has been most advantageous for bonding to gold and
other metals.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd
edn).St Louis, Mosby 1994: 542-623. 30

31. 3. Bonding to Amalgam:
Micro- etching is used for bonding to amalgam and
other precious metals.
Small amalgam restorations (eg: Buccal pit alloys)
may not need to be sandblasted before bonding molar
attachments, since the bond to the surrounding enamel is
usually sufficiently strong.
Large amalgams should be sandblasted for about 3
seconds to provide an improved surface for bonding.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd
edn).St Louis, Mosby 1994: 542-623.
31

32. 3.Fitting:
 Finally bracket is pressed firmly in its desired position with the
same scaler. It ensures good bond strength and also extrudes
extra material peripherally.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique
(2nd edn).St Louis, Mosby 1994: 542-623. 32

33.  After removal of the excess, the bonding agent is cured for the
complete polymerisation 40 seconds per tooth.
 While curing the metal brackets, the gun is directed from edges
of the bracket base and lingual sides of the teeth.
 For plastic and ceramic brackets it is directed on to the
brackets.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique
(2nd edn).St Louis, Mosby 1994: 542-623.
33

34. Most popular contemporary light curing systems are Light
Emitting Diodes.(LED).
They Emit light at 850 ω/sq.cm and takes about 20 seconds to
cure one attachment.
Other curing devices are---Halogen Curing Systems.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique
(2nd edn).St Louis, Mosby 1994: 542-623. 34

35. High-intensity halogen lights (“fast halogens”) Halogen
lights were followed by “fast halogens” with
halogen bulbs of increased light intensity and “turbo
tips” to focus the light emitted.
These provide a light intensity of 800 to 900
mW/cm2 and a wavelength range of 400 to
505 nm. Fast halogens can reduce curing time to
half that needed with conventional halogen lights.
35
RECENT ADVANCES:
Basaran G, Veli I. Modern Etching and Bonding Materials in Orthodontics:188

36.  Plasma arc units:
Plasma arc lamps have a tungsten anode and
a cathode in a quartz tube filled with xenon gas.
The gas becomes ionized and forms a plasma
that consists of negatively and positively charged
particles and that generates an intense white light
when an electrical current is passed through
the xenon. Plasma arc lights provide a light
intensity of 1200 to 1500 mW/cm2 and a
wavelength range of 380 to 495 nm.
36
Basaran G, Veli I. Modern Etching and Bonding Materials in Orthodontics:188

37. Light-emitting diodes:
Mills, Jandt, and Ashworth proposed solid-state light
emitting diode (LED) technology for the polymerization
of light-activated dental materials to overcome the
disadvantages of halogen visible-light curing units.
LEDs use junctions of “doped” semiconductors to
generate light instead of the hot filaments used in
halogen bulbs.
37
Basaran G, Veli I. Modern Etching and Bonding Materials in Orthodontics:188

38. Excessive composite around each bracket is so cleaned that
bracket position remains undisturbed.
It is important to remove the excess adhesive to prevent or
minimize gingival irritation or plaque build up around the
periphery of the bonding base.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique (2nd
edn).St Louis, Mosby 1994: 542-623. 38

39. Excess material should be removed with the help of a
scaler before the adhesive has set or with an oval or
tapered or tungsten carbide bur after the adhesive has set.
Graber TM, Vanarsdall RL. Orthodontics: Current Principles and Technique
(2nd edn).St Louis, Mosby 1994: 542-623. 39

40. Laser etching application:
Use of light for diagnosis and treatment has continued
since ancient history.
 When the laser light hits the tissue surface, a layer of
heated gas called "plasma" is generated.
 To minimize thermal effects on live tissue, air-water
cooling systems are used in the current erbium laser
systems.
Basaran G, Veli I. Modern Etching and Bonding Materials in Orthodontics:188 40

41. 41
NANOPARTICLES IN ORTHODONTIC ADHESIVES.
Composite materials and glass ionomer cements (GIC) have
been primarily used in orthodontics as adhesive agents for
securing orthodontic brackets and bands to the surface of the
teeth. The largest application of nanoparticles has been in dental
composite materials, where they have been used to enhance the
long-term optical properties by virtue of their small size and at
the same time provide superior mechanical strength and wear
resistance.
Karthikeyan Subramani1, Usha
Subbiah2 and Sarandeep Huja3

42.  There was also a potential for compromise in adhesion
between the macroscopic restorative material and the
nanoscopic (10 nm in size) tooth structure.
 Therefore, nanofilled composite materials were introduced.
There are two distinct types of dental nanocomposites
currently available: nanofills and nanohybrids .
 Nano fills contain nanometer-sized particles (100 nm)
throughout the resin matrix, with no other large primary
particles included.
 Nanohybrids consist of larger particles (400-5000 nm) with
added nanometer-sized particles.
 The use of nano particles addresses the afore mentioned
difficulty by combining high mechanical strength with long-
term polish retention in one material.
42

43. New nano filled bonding agent vs Conventional
Bonding agent:
A recent study showed that both nano-filled bonding
agent and Conventional Bonding agent both showed
clinically acceptable bonding strength, however bonding
with nano-filled bonding agent is more cumbersome as
compared to conventional bonding hence latter is more
preferred.
Pai SS, Nagendra A,Pai VS, Neelima K, Vishwanath AE,Vinod P, Kumar
SA,Tubaki RR. Evaluation of a new Nano –filled Bonding Agent for Bonding
Orthodontic Brackets as compared to a conventional bonding Agent: An
invitro study. J Ind Orthod Soc 2012: 46(4): 329-333
43

44. 1.Kharbanda OP. Orthodontics Diagnosis and Management of
Malocclusion and Dentofacial Deformities(2nd Edition).Elsevier: 346-
354
2.Roberson TM, Heymann HO, Swift EJ. Orthodontics: Sturdevant’s Art
and Science of Operative Dentistry (4th edn).Mosby 2002: 2
3.Kugel G, Ferrari M. The science of bonding:from first to sixth
generation.American dental association ; 131:20
4.Pai SS, Nagendra A,Pai VS, Neelima K, Vishwanath AE,Vinod P,
Kumar SA,Tubaki RR. Evaluation of a new Nano –filled Bonding
Agent for Bonding Orthodontic Brackets as compared to a
conventional bonding Agent: An invitro study. J Ind Orthod Soc 2012:
46(4): 329-333
5.Basaran G, Veli I. Modern Etching and Bonding Materials in
Orthodontics:188
44

45. 45